summaryrefslogtreecommitdiff
path: root/net/unix
AgeCommit message (Collapse)Author
2024-02-21af_unix: Drop oob_skb ref before purging queue in GC.Kuniyuki Iwashima
syzbot reported another task hung in __unix_gc(). [0] The current while loop assumes that all of the left candidates have oob_skb and calling kfree_skb(oob_skb) releases the remaining candidates. However, I missed a case that oob_skb has self-referencing fd and another fd and the latter sk is placed before the former in the candidate list. Then, the while loop never proceeds, resulting the task hung. __unix_gc() has the same loop just before purging the collected skb, so we can call kfree_skb(oob_skb) there and let __skb_queue_purge() release all inflight sockets. [0]: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2784 Comm: kworker/u4:8 Not tainted 6.8.0-rc4-syzkaller-01028-g71b605d32017 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: events_unbound __unix_gc RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:200 Code: 89 fb e8 23 00 00 00 48 8b 3d 84 f5 1a 0c 48 89 de 5b e9 43 26 57 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0d 90 52 70 7e 65 8b 15 91 52 70 RSP: 0018:ffffc9000a17fa78 EFLAGS: 00000287 RAX: ffffffff8a0a6108 RBX: ffff88802b6c2640 RCX: ffff88802c0b3b80 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000 RBP: ffffc9000a17fbf0 R08: ffffffff89383f1d R09: 1ffff1100ee5ff84 R10: dffffc0000000000 R11: ffffed100ee5ff85 R12: 1ffff110056d84ee R13: ffffc9000a17fae0 R14: 0000000000000000 R15: ffffffff8f47b840 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffef5687ff8 CR3: 0000000029b34000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <TASK> __unix_gc+0xe69/0xf40 net/unix/garbage.c:343 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 </TASK> Reported-and-tested-by: syzbot+ecab4d36f920c3574bf9@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=ecab4d36f920c3574bf9 Fixes: 25236c91b5ab ("af_unix: Fix task hung while purging oob_skb in GC.") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-21net: implement lockless setsockopt(SO_PEEK_OFF)Eric Dumazet
syzbot reported a lockdep violation [1] involving af_unix support of SO_PEEK_OFF. Since SO_PEEK_OFF is inherently not thread safe (it uses a per-socket sk_peek_off field), there is really no point to enforce a pointless thread safety in the kernel. After this patch : - setsockopt(SO_PEEK_OFF) no longer acquires the socket lock. - skb_consume_udp() no longer has to acquire the socket lock. - af_unix no longer needs a special version of sk_set_peek_off(), because it does not lock u->iolock anymore. As a followup, we could replace prot->set_peek_off to be a boolean and avoid an indirect call, since we always use sk_set_peek_off(). [1] WARNING: possible circular locking dependency detected 6.8.0-rc4-syzkaller-00267-g0f1dd5e91e2b #0 Not tainted syz-executor.2/30025 is trying to acquire lock: ffff8880765e7d80 (&u->iolock){+.+.}-{3:3}, at: unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789 but task is already holding lock: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1691 [inline] ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sockopt_lock_sock net/core/sock.c:1060 [inline] ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sk_setsockopt+0xe52/0x3360 net/core/sock.c:1193 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (sk_lock-AF_UNIX){+.+.}-{0:0}: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 lock_sock_nested+0x48/0x100 net/core/sock.c:3524 lock_sock include/net/sock.h:1691 [inline] __unix_dgram_recvmsg+0x1275/0x12c0 net/unix/af_unix.c:2415 sock_recvmsg_nosec+0x18e/0x1d0 net/socket.c:1046 ____sys_recvmsg+0x3c0/0x470 net/socket.c:2801 ___sys_recvmsg net/socket.c:2845 [inline] do_recvmmsg+0x474/0xae0 net/socket.c:2939 __sys_recvmmsg net/socket.c:3018 [inline] __do_sys_recvmmsg net/socket.c:3041 [inline] __se_sys_recvmmsg net/socket.c:3034 [inline] __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3034 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 -> #0 (&u->iolock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18ca/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789 sk_setsockopt+0x207e/0x3360 do_sock_setsockopt+0x2fb/0x720 net/socket.c:2307 __sys_setsockopt+0x1ad/0x250 net/socket.c:2334 __do_sys_setsockopt net/socket.c:2343 [inline] __se_sys_setsockopt net/socket.c:2340 [inline] __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_UNIX); lock(&u->iolock); lock(sk_lock-AF_UNIX); lock(&u->iolock); *** DEADLOCK *** 1 lock held by syz-executor.2/30025: #0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1691 [inline] #0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sockopt_lock_sock net/core/sock.c:1060 [inline] #0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sk_setsockopt+0xe52/0x3360 net/core/sock.c:1193 stack backtrace: CPU: 0 PID: 30025 Comm: syz-executor.2 Not tainted 6.8.0-rc4-syzkaller-00267-g0f1dd5e91e2b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18ca/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789 sk_setsockopt+0x207e/0x3360 do_sock_setsockopt+0x2fb/0x720 net/socket.c:2307 __sys_setsockopt+0x1ad/0x250 net/socket.c:2334 __do_sys_setsockopt net/socket.c:2343 [inline] __se_sys_setsockopt net/socket.c:2340 [inline] __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f78a1c7dda9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f78a0fde0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f78a1dac050 RCX: 00007f78a1c7dda9 RDX: 000000000000002a RSI: 0000000000000001 RDI: 0000000000000006 RBP: 00007f78a1cca47a R08: 0000000000000004 R09: 0000000000000000 R10: 0000000020000180 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f78a1dac050 R15: 00007ffe5cd81ae8 Fixes: 859051dd165e ("bpf: Implement cgroup sockaddr hooks for unix sockets") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Cc: Daan De Meyer <daan.j.demeyer@gmail.com> Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Cc: Martin KaFai Lau <martin.lau@kernel.org> Cc: David Ahern <dsahern@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-13af_unix: Fix task hung while purging oob_skb in GC.Kuniyuki Iwashima
syzbot reported a task hung; at the same time, GC was looping infinitely in list_for_each_entry_safe() for OOB skb. [0] syzbot demonstrated that the list_for_each_entry_safe() was not actually safe in this case. A single skb could have references for multiple sockets. If we free such a skb in the list_for_each_entry_safe(), the current and next sockets could be unlinked in a single iteration. unix_notinflight() uses list_del_init() to unlink the socket, so the prefetched next socket forms a loop itself and list_for_each_entry_safe() never stops. Here, we must use while() and make sure we always fetch the first socket. [0]: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5065 Comm: syz-executor236 Not tainted 6.8.0-rc3-syzkaller-00136-g1f719a2f3fa6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:173 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0xd/0x60 kernel/kcov.c:207 Code: cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 65 48 8b 14 25 40 c2 03 00 <65> 8b 05 b4 7c 78 7e a9 00 01 ff 00 48 8b 34 24 74 0f f6 c4 01 74 RSP: 0018:ffffc900033efa58 EFLAGS: 00000283 RAX: ffff88807b077800 RBX: ffff88807b077800 RCX: 1ffffffff27b1189 RDX: ffff88802a5a3b80 RSI: ffffffff8968488d RDI: ffff88807b077f70 RBP: ffffc900033efbb0 R08: 0000000000000001 R09: fffffbfff27a900c R10: ffffffff93d48067 R11: ffffffff8ae000eb R12: ffff88807b077800 R13: dffffc0000000000 R14: ffff88807b077e40 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000564f4fc1e3a8 CR3: 000000000d57a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <TASK> unix_gc+0x563/0x13b0 net/unix/garbage.c:319 unix_release_sock+0xa93/0xf80 net/unix/af_unix.c:683 unix_release+0x91/0xf0 net/unix/af_unix.c:1064 __sock_release+0xb0/0x270 net/socket.c:659 sock_close+0x1c/0x30 net/socket.c:1421 __fput+0x270/0xb80 fs/file_table.c:376 task_work_run+0x14f/0x250 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa8a/0x2ad0 kernel/exit.c:871 do_group_exit+0xd4/0x2a0 kernel/exit.c:1020 __do_sys_exit_group kernel/exit.c:1031 [inline] __se_sys_exit_group kernel/exit.c:1029 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1029 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd5/0x270 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f9d6cbdac09 Code: Unable to access opcode bytes at 0x7f9d6cbdabdf. RSP: 002b:00007fff5952feb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9d6cbdac09 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 00007f9d6cc552b0 R08: ffffffffffffffb8 R09: 0000000000000006 R10: 0000000000000006 R11: 0000000000000246 R12: 00007f9d6cc552b0 R13: 0000000000000000 R14: 00007f9d6cc55d00 R15: 00007f9d6cbabe70 </TASK> Reported-by: syzbot+4fa4a2d1f5a5ee06f006@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=4fa4a2d1f5a5ee06f006 Fixes: 1279f9d9dec2 ("af_unix: Call kfree_skb() for dead unix_(sk)->oob_skb in GC.") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20240209220453.96053-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-06af_unix: Call kfree_skb() for dead unix_(sk)->oob_skb in GC.Kuniyuki Iwashima
syzbot reported a warning [0] in __unix_gc() with a repro, which creates a socketpair and sends one socket's fd to itself using the peer. socketpair(AF_UNIX, SOCK_STREAM, 0, [3, 4]) = 0 sendmsg(4, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\360", iov_len=1}], msg_iovlen=1, msg_control=[{cmsg_len=20, cmsg_level=SOL_SOCKET, cmsg_type=SCM_RIGHTS, cmsg_data=[3]}], msg_controllen=24, msg_flags=0}, MSG_OOB|MSG_PROBE|MSG_DONTWAIT|MSG_ZEROCOPY) = 1 This forms a self-cyclic reference that GC should finally untangle but does not due to lack of MSG_OOB handling, resulting in memory leak. Recently, commit 11498715f266 ("af_unix: Remove io_uring code for GC.") removed io_uring's dead code in GC and revealed the problem. The code was executed at the final stage of GC and unconditionally moved all GC candidates from gc_candidates to gc_inflight_list. That papered over the reported problem by always making the following WARN_ON_ONCE(!list_empty(&gc_candidates)) false. The problem has been there since commit 2aab4b969002 ("af_unix: fix struct pid leaks in OOB support") added full scm support for MSG_OOB while fixing another bug. To fix this problem, we must call kfree_skb() for unix_sk(sk)->oob_skb if the socket still exists in gc_candidates after purging collected skb. Then, we need to set NULL to oob_skb before calling kfree_skb() because it calls last fput() and triggers unix_release_sock(), where we call duplicate kfree_skb(u->oob_skb) if not NULL. Note that the leaked socket remained being linked to a global list, so kmemleak also could not detect it. We need to check /proc/net/protocol to notice the unfreed socket. [0]: WARNING: CPU: 0 PID: 2863 at net/unix/garbage.c:345 __unix_gc+0xc74/0xe80 net/unix/garbage.c:345 Modules linked in: CPU: 0 PID: 2863 Comm: kworker/u4:11 Not tainted 6.8.0-rc1-syzkaller-00583-g1701940b1a02 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: events_unbound __unix_gc RIP: 0010:__unix_gc+0xc74/0xe80 net/unix/garbage.c:345 Code: 8b 5c 24 50 e9 86 f8 ff ff e8 f8 e4 22 f8 31 d2 48 c7 c6 30 6a 69 89 4c 89 ef e8 97 ef ff ff e9 80 f9 ff ff e8 dd e4 22 f8 90 <0f> 0b 90 e9 7b fd ff ff 48 89 df e8 5c e7 7c f8 e9 d3 f8 ff ff e8 RSP: 0018:ffffc9000b03fba0 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffffc9000b03fc10 RCX: ffffffff816c493e RDX: ffff88802c02d940 RSI: ffffffff896982f3 RDI: ffffc9000b03fb30 RBP: ffffc9000b03fce0 R08: 0000000000000001 R09: fffff52001607f66 R10: 0000000000000003 R11: 0000000000000002 R12: dffffc0000000000 R13: ffffc9000b03fc10 R14: ffffc9000b03fc10 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005559c8677a60 CR3: 000000000d57a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> process_one_work+0x889/0x15e0 kernel/workqueue.c:2633 process_scheduled_works kernel/workqueue.c:2706 [inline] worker_thread+0x8b9/0x12a0 kernel/workqueue.c:2787 kthread+0x2c6/0x3b0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 </TASK> Reported-by: syzbot+fa3ef895554bdbfd1183@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=fa3ef895554bdbfd1183 Fixes: 2aab4b969002 ("af_unix: fix struct pid leaks in OOB support") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240203183149.63573-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-31af_unix: fix lockdep positive in sk_diag_dump_icons()Eric Dumazet
syzbot reported a lockdep splat [1]. Blamed commit hinted about the possible lockdep violation, and code used unix_state_lock_nested() in an attempt to silence lockdep. It is not sufficient, because unix_state_lock_nested() is already used from unix_state_double_lock(). We need to use a separate subclass. This patch adds a distinct enumeration to make things more explicit. Also use swap() in unix_state_double_lock() as a clean up. v2: add a missing inline keyword to unix_state_lock_nested() [1] WARNING: possible circular locking dependency detected 6.8.0-rc1-syzkaller-00356-g8a696a29c690 #0 Not tainted syz-executor.1/2542 is trying to acquire lock: ffff88808b5df9e8 (rlock-AF_UNIX){+.+.}-{2:2}, at: skb_queue_tail+0x36/0x120 net/core/skbuff.c:3863 but task is already holding lock: ffff88808b5dfe70 (&u->lock/1){+.+.}-{2:2}, at: unix_dgram_sendmsg+0xfc7/0x2200 net/unix/af_unix.c:2089 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&u->lock/1){+.+.}-{2:2}: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378 sk_diag_dump_icons net/unix/diag.c:87 [inline] sk_diag_fill+0x6ea/0xfe0 net/unix/diag.c:157 sk_diag_dump net/unix/diag.c:196 [inline] unix_diag_dump+0x3e9/0x630 net/unix/diag.c:220 netlink_dump+0x5c1/0xcd0 net/netlink/af_netlink.c:2264 __netlink_dump_start+0x5d7/0x780 net/netlink/af_netlink.c:2370 netlink_dump_start include/linux/netlink.h:338 [inline] unix_diag_handler_dump+0x1c3/0x8f0 net/unix/diag.c:319 sock_diag_rcv_msg+0xe3/0x400 netlink_rcv_skb+0x1df/0x430 net/netlink/af_netlink.c:2543 sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:280 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0x7e6/0x980 net/netlink/af_netlink.c:1367 netlink_sendmsg+0xa37/0xd70 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] sock_write_iter+0x39a/0x520 net/socket.c:1160 call_write_iter include/linux/fs.h:2085 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa74/0xca0 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b -> #0 (rlock-AF_UNIX){+.+.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x1909/0x5ab0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 skb_queue_tail+0x36/0x120 net/core/skbuff.c:3863 unix_dgram_sendmsg+0x15d9/0x2200 net/unix/af_unix.c:2112 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x592/0x890 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmmsg+0x3b2/0x730 net/socket.c:2724 __do_sys_sendmmsg net/socket.c:2753 [inline] __se_sys_sendmmsg net/socket.c:2750 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2750 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&u->lock/1); lock(rlock-AF_UNIX); lock(&u->lock/1); lock(rlock-AF_UNIX); *** DEADLOCK *** 1 lock held by syz-executor.1/2542: #0: ffff88808b5dfe70 (&u->lock/1){+.+.}-{2:2}, at: unix_dgram_sendmsg+0xfc7/0x2200 net/unix/af_unix.c:2089 stack backtrace: CPU: 1 PID: 2542 Comm: syz-executor.1 Not tainted 6.8.0-rc1-syzkaller-00356-g8a696a29c690 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 check_noncircular+0x366/0x490 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x1909/0x5ab0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 skb_queue_tail+0x36/0x120 net/core/skbuff.c:3863 unix_dgram_sendmsg+0x15d9/0x2200 net/unix/af_unix.c:2112 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x592/0x890 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmmsg+0x3b2/0x730 net/socket.c:2724 __do_sys_sendmmsg net/socket.c:2753 [inline] __se_sys_sendmmsg net/socket.c:2750 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2750 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f26d887cda9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f26d95a60c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f26d89abf80 RCX: 00007f26d887cda9 RDX: 000000000000003e RSI: 00000000200bd000 RDI: 0000000000000004 RBP: 00007f26d88c947a R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000008c0 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f26d89abf80 R15: 00007ffcfe081a68 Fixes: 2aac7a2cb0d9 ("unix_diag: Pending connections IDs NLA") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20240130184235.1620738-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-11Merge tag 'for-6.8/io_uring-2024-01-08' of git://git.kernel.dk/linuxLinus Torvalds
Pull io_uring updates from Jens Axboe: "Mostly just come fixes and cleanups, but one feature as well. In detail: - Harden the check for handling IOPOLL based on return (Pavel) - Various minor optimizations (Pavel) - Drop remnants of SCM_RIGHTS fd passing support, now that it's no longer supported since 6.7 (me) - Fix for a case where bytes_done wasn't initialized properly on a failure condition for read/write requests (me) - Move the register related code to a separate file (me) - Add support for returning the provided ring buffer head (me) - Add support for adding a direct descriptor to the normal file table (me, Christian Brauner) - Fix for ensuring pending task_work for a ring with DEFER_TASKRUN is run even if we timeout waiting (me)" * tag 'for-6.8/io_uring-2024-01-08' of git://git.kernel.dk/linux: io_uring: ensure local task_work is run on wait timeout io_uring/kbuf: add method for returning provided buffer ring head io_uring/rw: ensure io->bytes_done is always initialized io_uring: drop any code related to SCM_RIGHTS io_uring/unix: drop usage of io_uring socket io_uring/register: move io_uring_register(2) related code to register.c io_uring/openclose: add support for IORING_OP_FIXED_FD_INSTALL io_uring/cmd: inline io_uring_cmd_get_task io_uring/cmd: inline io_uring_cmd_do_in_task_lazy io_uring: split out cmd api into a separate header io_uring: optimise ltimeout for inline execution io_uring: don't check iopoll if request completes
2024-01-03bpf: sockmap, fix proto update hook to avoid dup callsJohn Fastabend
When sockets are added to a sockmap or sockhash we allocate and init a psock. Then update the proto ops with sock_map_init_proto the flow is sock_hash_update_common sock_map_link psock = sock_map_psock_get_checked() <-returns existing psock sock_map_init_proto(sk, psock) <- updates sk_proto If the socket is already in a map this results in the sock_map_init_proto being called multiple times on the same socket. We do this because when a socket is added to multiple maps this might result in a new set of BPF programs being attached to the socket requiring an updated ops struct. This creates a rule where it must be safe to call psock_update_sk_prot multiple times. When we added a fix for UAF through unix sockets in patch 4dd9a38a753fc we broke this rule by adding a sock_hold in that path to ensure the sock is not released. The result is if a af_unix stream sock is placed in multiple maps it results in a memory leak because we call sock_hold multiple times with only a single sock_put on it. Fixes: 8866730aed51 ("bpf, sockmap: af_unix stream sockets need to hold ref for pair sock") Reported-by: Xingwei Lee <xrivendell7@gmail.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/r/20231221232327.43678-2-john.fastabend@gmail.com
2023-12-19io_uring/unix: drop usage of io_uring socketJens Axboe
Since we no longer allow sending io_uring fds over SCM_RIGHTS, move to using io_is_uring_fops() to detect whether this is a io_uring fd or not. With that done, kill off io_uring_get_socket() as nobody calls it anymore. This is in preparation to yanking out the rest of the core related to unix gc with io_uring. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-11-30bpf, sockmap: af_unix stream sockets need to hold ref for pair sockJohn Fastabend
AF_UNIX stream sockets are a paired socket. So sending on one of the pairs will lookup the paired socket as part of the send operation. It is possible however to put just one of the pairs in a BPF map. This currently increments the refcnt on the sock in the sockmap to ensure it is not free'd by the stack before sockmap cleans up its state and stops any skbs being sent/recv'd to that socket. But we missed a case. If the peer socket is closed it will be free'd by the stack. However, the paired socket can still be referenced from BPF sockmap side because we hold a reference there. Then if we are sending traffic through BPF sockmap to that socket it will try to dereference the free'd pair in its send logic creating a use after free. And following splat: [59.900375] BUG: KASAN: slab-use-after-free in sk_wake_async+0x31/0x1b0 [59.901211] Read of size 8 at addr ffff88811acbf060 by task kworker/1:2/954 [...] [59.905468] Call Trace: [59.905787] <TASK> [59.906066] dump_stack_lvl+0x130/0x1d0 [59.908877] print_report+0x16f/0x740 [59.910629] kasan_report+0x118/0x160 [59.912576] sk_wake_async+0x31/0x1b0 [59.913554] sock_def_readable+0x156/0x2a0 [59.914060] unix_stream_sendmsg+0x3f9/0x12a0 [59.916398] sock_sendmsg+0x20e/0x250 [59.916854] skb_send_sock+0x236/0xac0 [59.920527] sk_psock_backlog+0x287/0xaa0 To fix let BPF sockmap hold a refcnt on both the socket in the sockmap and its paired socket. It wasn't obvious how to contain the fix to bpf_unix logic. The primarily problem with keeping this logic in bpf_unix was: In the sock close() we could handle the deref by having a close handler. But, when we are destroying the psock through a map delete operation we wouldn't have gotten any signal thorugh the proto struct other than it being replaced. If we do the deref from the proto replace its too early because we need to deref the sk_pair after the backlog worker has been stopped. Given all this it seems best to just cache it at the end of the psock and eat 8B for the af_unix and vsock users. Notice dgram sockets are OK because they handle locking already. Fixes: 94531cfcbe79 ("af_unix: Add unix_stream_proto for sockmap") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20231129012557.95371-2-john.fastabend@gmail.com
2023-11-19net: fill in MODULE_DESCRIPTION()s for SOCK_DIAG modulesJakub Kicinski
W=1 builds now warn if module is built without a MODULE_DESCRIPTION(). Add descriptions to all the sock diag modules in one fell swoop. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-11-14af_unix: fix use-after-free in unix_stream_read_actor()Eric Dumazet
syzbot reported the following crash [1] After releasing unix socket lock, u->oob_skb can be changed by another thread. We must temporarily increase skb refcount to make sure this other thread will not free the skb under us. [1] BUG: KASAN: slab-use-after-free in unix_stream_read_actor+0xa7/0xc0 net/unix/af_unix.c:2866 Read of size 4 at addr ffff88801f3b9cc4 by task syz-executor107/5297 CPU: 1 PID: 5297 Comm: syz-executor107 Not tainted 6.6.0-syzkaller-15910-gb8e3a87a627b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 unix_stream_read_actor+0xa7/0xc0 net/unix/af_unix.c:2866 unix_stream_recv_urg net/unix/af_unix.c:2587 [inline] unix_stream_read_generic+0x19a5/0x2480 net/unix/af_unix.c:2666 unix_stream_recvmsg+0x189/0x1b0 net/unix/af_unix.c:2903 sock_recvmsg_nosec net/socket.c:1044 [inline] sock_recvmsg+0xe2/0x170 net/socket.c:1066 ____sys_recvmsg+0x21f/0x5c0 net/socket.c:2803 ___sys_recvmsg+0x115/0x1a0 net/socket.c:2845 __sys_recvmsg+0x114/0x1e0 net/socket.c:2875 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7fc67492c559 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc6748ab228 EFLAGS: 00000246 ORIG_RAX: 000000000000002f RAX: ffffffffffffffda RBX: 000000000000001c RCX: 00007fc67492c559 RDX: 0000000040010083 RSI: 0000000020000140 RDI: 0000000000000004 RBP: 00007fc6749b6348 R08: 00007fc6748ab6c0 R09: 00007fc6748ab6c0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc6749b6340 R13: 00007fc6749b634c R14: 00007ffe9fac52a0 R15: 00007ffe9fac5388 </TASK> Allocated by task 5295: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:763 [inline] slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x180/0x3c0 mm/slub.c:3523 __alloc_skb+0x287/0x330 net/core/skbuff.c:641 alloc_skb include/linux/skbuff.h:1286 [inline] alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6331 sock_alloc_send_pskb+0x7e4/0x970 net/core/sock.c:2780 sock_alloc_send_skb include/net/sock.h:1884 [inline] queue_oob net/unix/af_unix.c:2147 [inline] unix_stream_sendmsg+0xb5f/0x10a0 net/unix/af_unix.c:2301 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2584 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2638 __sys_sendmsg+0x117/0x1e0 net/socket.c:2667 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b Freed by task 5295: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x15b/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] kmem_cache_free+0xf8/0x340 mm/slub.c:3831 kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:1015 __kfree_skb net/core/skbuff.c:1073 [inline] consume_skb net/core/skbuff.c:1288 [inline] consume_skb+0xdf/0x170 net/core/skbuff.c:1282 queue_oob net/unix/af_unix.c:2178 [inline] unix_stream_sendmsg+0xd49/0x10a0 net/unix/af_unix.c:2301 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2584 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2638 __sys_sendmsg+0x117/0x1e0 net/socket.c:2667 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b The buggy address belongs to the object at ffff88801f3b9c80 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 68 bytes inside of freed 240-byte region [ffff88801f3b9c80, ffff88801f3b9d70) The buggy address belongs to the physical page: page:ffffea00007cee40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1f3b9 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888142a60640 dead000000000122 0000000000000000 raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 5299, tgid 5283 (syz-executor107), ts 103803840339, free_ts 103600093431 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1544 [inline] get_page_from_freelist+0xa25/0x36c0 mm/page_alloc.c:3312 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4568 alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x251/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8c7/0x1580 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] kmem_cache_alloc_node+0x132/0x3c0 mm/slub.c:3523 __alloc_skb+0x287/0x330 net/core/skbuff.c:641 alloc_skb include/linux/skbuff.h:1286 [inline] alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6331 sock_alloc_send_pskb+0x7e4/0x970 net/core/sock.c:2780 sock_alloc_send_skb include/net/sock.h:1884 [inline] queue_oob net/unix/af_unix.c:2147 [inline] unix_stream_sendmsg+0xb5f/0x10a0 net/unix/af_unix.c:2301 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2584 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2638 __sys_sendmsg+0x117/0x1e0 net/socket.c:2667 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1137 [inline] free_unref_page_prepare+0x4f8/0xa90 mm/page_alloc.c:2347 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2487 __unfreeze_partials+0x21d/0x240 mm/slub.c:2655 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:763 [inline] slab_alloc_node mm/slub.c:3478 [inline] slab_alloc mm/slub.c:3486 [inline] __kmem_cache_alloc_lru mm/slub.c:3493 [inline] kmem_cache_alloc+0x15d/0x380 mm/slub.c:3502 vm_area_dup+0x21/0x2f0 kernel/fork.c:500 __split_vma+0x17d/0x1070 mm/mmap.c:2365 split_vma mm/mmap.c:2437 [inline] vma_modify+0x25d/0x450 mm/mmap.c:2472 vma_modify_flags include/linux/mm.h:3271 [inline] mprotect_fixup+0x228/0xc80 mm/mprotect.c:635 do_mprotect_pkey+0x852/0xd60 mm/mprotect.c:809 __do_sys_mprotect mm/mprotect.c:830 [inline] __se_sys_mprotect mm/mprotect.c:827 [inline] __x64_sys_mprotect+0x78/0xb0 mm/mprotect.c:827 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b Memory state around the buggy address: ffff88801f3b9b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801f3b9c00: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc >ffff88801f3b9c80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801f3b9d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff88801f3b9d80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb Fixes: 876c14ad014d ("af_unix: fix holding spinlock in oob handling") Reported-and-tested-by: syzbot+7a2d546fa43e49315ed3@syzkaller.appspotmail.com Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Rao Shoaib <rao.shoaib@oracle.com> Reviewed-by: Rao shoaib <rao.shoaib@oracle.com> Link: https://lore.kernel.org/r/20231113134938.168151-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-10-27af_unix: Remove module remnants.Kuniyuki Iwashima
Since commit 97154bcf4d1b ("af_unix: Kconfig: make CONFIG_UNIX bool"), af_unix.c is no longer built as module. Let's remove unnecessary #if condition, exitcall, and module macros. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20231026212305.45545-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-11bpf: Implement cgroup sockaddr hooks for unix socketsDaan De Meyer
These hooks allows intercepting connect(), getsockname(), getpeername(), sendmsg() and recvmsg() for unix sockets. The unix socket hooks get write access to the address length because the address length is not fixed when dealing with unix sockets and needs to be modified when a unix socket address is modified by the hook. Because abstract socket unix addresses start with a NUL byte, we cannot recalculate the socket address in kernelspace after running the hook by calculating the length of the unix socket path using strlen(). These hooks can be used when users want to multiplex syscall to a single unix socket to multiple different processes behind the scenes by redirecting the connect() and other syscalls to process specific sockets. We do not implement support for intercepting bind() because when using bind() with unix sockets with a pathname address, this creates an inode in the filesystem which must be cleaned up. If we rewrite the address, the user might try to clean up the wrong file, leaking the socket in the filesystem where it is never cleaned up. Until we figure out a solution for this (and a use case for intercepting bind()), we opt to not allow rewriting the sockaddr in bind() calls. We also implement recvmsg() support for connected streams so that after a connect() that is modified by a sockaddr hook, any corresponding recmvsg() on the connected socket can also be modified to make the connected program think it is connected to the "intended" remote. Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com> Link: https://lore.kernel.org/r/20231011185113.140426-5-daan.j.demeyer@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2023-09-07Merge tag 'net-6.6-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking updates from Jakub Kicinski: "Including fixes from netfilter and bpf. Current release - regressions: - eth: stmmac: fix failure to probe without MAC interface specified Current release - new code bugs: - docs: netlink: fix missing classic_netlink doc reference Previous releases - regressions: - deal with integer overflows in kmalloc_reserve() - use sk_forward_alloc_get() in sk_get_meminfo() - bpf_sk_storage: fix the missing uncharge in sk_omem_alloc - fib: avoid warn splat in flow dissector after packet mangling - skb_segment: call zero copy functions before using skbuff frags - eth: sfc: check for zero length in EF10 RX prefix Previous releases - always broken: - af_unix: fix msg_controllen test in scm_pidfd_recv() for MSG_CMSG_COMPAT - xsk: fix xsk_build_skb() dereferencing possible ERR_PTR() - netfilter: - nft_exthdr: fix non-linear header modification - xt_u32, xt_sctp: validate user space input - nftables: exthdr: fix 4-byte stack OOB write - nfnetlink_osf: avoid OOB read - one more fix for the garbage collection work from last release - igmp: limit igmpv3_newpack() packet size to IP_MAX_MTU - bpf, sockmap: fix preempt_rt splat when using raw_spin_lock_t - handshake: fix null-deref in handshake_nl_done_doit() - ip: ignore dst hint for multipath routes to ensure packets are hashed across the nexthops - phy: micrel: - correct bit assignments for cable test errata - disable EEE according to the KSZ9477 errata Misc: - docs/bpf: document compile-once-run-everywhere (CO-RE) relocations - Revert "net: macsec: preserve ingress frame ordering", it appears to have been developed against an older kernel, problem doesn't exist upstream" * tag 'net-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (95 commits) net: enetc: distinguish error from valid pointers in enetc_fixup_clear_rss_rfs() Revert "net: team: do not use dynamic lockdep key" net: hns3: remove GSO partial feature bit net: hns3: fix the port information display when sfp is absent net: hns3: fix invalid mutex between tc qdisc and dcb ets command issue net: hns3: fix debugfs concurrency issue between kfree buffer and read net: hns3: fix byte order conversion issue in hclge_dbg_fd_tcam_read() net: hns3: Support query tx timeout threshold by debugfs net: hns3: fix tx timeout issue net: phy: Provide Module 4 KSZ9477 errata (DS80000754C) netfilter: nf_tables: Unbreak audit log reset netfilter: ipset: add the missing IP_SET_HASH_WITH_NET0 macro for ip_set_hash_netportnet.c netfilter: nft_set_rbtree: skip sync GC for new elements in this transaction netfilter: nf_tables: uapi: Describe NFTA_RULE_CHAIN_ID netfilter: nfnetlink_osf: avoid OOB read netfilter: nftables: exthdr: fix 4-byte stack OOB write selftests/bpf: Check bpf_sk_storage has uncharged sk_omem_alloc bpf: bpf_sk_storage: Fix the missing uncharge in sk_omem_alloc bpf: bpf_sk_storage: Fix invalid wait context lockdep report s390/bpf: Pass through tail call counter in trampolines ...
2023-09-04af_unix: Fix data-race around unix_tot_inflight.Kuniyuki Iwashima
unix_tot_inflight is changed under spin_lock(unix_gc_lock), but unix_release_sock() reads it locklessly. Let's use READ_ONCE() for unix_tot_inflight. Note that the writer side was marked by commit 9d6d7f1cb67c ("af_unix: annote lockless accesses to unix_tot_inflight & gc_in_progress") BUG: KCSAN: data-race in unix_inflight / unix_release_sock write (marked) to 0xffffffff871852b8 of 4 bytes by task 123 on cpu 1: unix_inflight+0x130/0x180 net/unix/scm.c:64 unix_attach_fds+0x137/0x1b0 net/unix/scm.c:123 unix_scm_to_skb net/unix/af_unix.c:1832 [inline] unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1955 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg+0x148/0x160 net/socket.c:747 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2493 ___sys_sendmsg+0xc6/0x140 net/socket.c:2547 __sys_sendmsg+0x94/0x140 net/socket.c:2576 __do_sys_sendmsg net/socket.c:2585 [inline] __se_sys_sendmsg net/socket.c:2583 [inline] __x64_sys_sendmsg+0x45/0x50 net/socket.c:2583 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc read to 0xffffffff871852b8 of 4 bytes by task 4891 on cpu 0: unix_release_sock+0x608/0x910 net/unix/af_unix.c:671 unix_release+0x59/0x80 net/unix/af_unix.c:1058 __sock_release+0x7d/0x170 net/socket.c:653 sock_close+0x19/0x30 net/socket.c:1385 __fput+0x179/0x5e0 fs/file_table.c:321 ____fput+0x15/0x20 fs/file_table.c:349 task_work_run+0x116/0x1a0 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x174/0x180 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:297 do_syscall_64+0x4b/0x90 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x72/0xdc value changed: 0x00000000 -> 0x00000001 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 4891 Comm: systemd-coredum Not tainted 6.4.0-rc5-01219-gfa0e21fa4443 #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Fixes: 9305cfa4443d ("[AF_UNIX]: Make unix_tot_inflight counter non-atomic") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-04af_unix: Fix data-races around user->unix_inflight.Kuniyuki Iwashima
user->unix_inflight is changed under spin_lock(unix_gc_lock), but too_many_unix_fds() reads it locklessly. Let's annotate the write/read accesses to user->unix_inflight. BUG: KCSAN: data-race in unix_attach_fds / unix_inflight write to 0xffffffff8546f2d0 of 8 bytes by task 44798 on cpu 1: unix_inflight+0x157/0x180 net/unix/scm.c:66 unix_attach_fds+0x147/0x1e0 net/unix/scm.c:123 unix_scm_to_skb net/unix/af_unix.c:1827 [inline] unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1950 unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline] unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg+0x148/0x160 net/socket.c:748 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2494 ___sys_sendmsg+0xc6/0x140 net/socket.c:2548 __sys_sendmsg+0x94/0x140 net/socket.c:2577 __do_sys_sendmsg net/socket.c:2586 [inline] __se_sys_sendmsg net/socket.c:2584 [inline] __x64_sys_sendmsg+0x45/0x50 net/socket.c:2584 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 read to 0xffffffff8546f2d0 of 8 bytes by task 44814 on cpu 0: too_many_unix_fds net/unix/scm.c:101 [inline] unix_attach_fds+0x54/0x1e0 net/unix/scm.c:110 unix_scm_to_skb net/unix/af_unix.c:1827 [inline] unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1950 unix_seqpacket_sendmsg net/unix/af_unix.c:2308 [inline] unix_seqpacket_sendmsg+0xba/0x130 net/unix/af_unix.c:2292 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg+0x148/0x160 net/socket.c:748 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2494 ___sys_sendmsg+0xc6/0x140 net/socket.c:2548 __sys_sendmsg+0x94/0x140 net/socket.c:2577 __do_sys_sendmsg net/socket.c:2586 [inline] __se_sys_sendmsg net/socket.c:2584 [inline] __x64_sys_sendmsg+0x45/0x50 net/socket.c:2584 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 value changed: 0x000000000000000c -> 0x000000000000000d Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 44814 Comm: systemd-coredum Not tainted 6.4.0-11989-g6843306689af #6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Fixes: 712f4aad406b ("unix: properly account for FDs passed over unix sockets") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Willy Tarreau <w@1wt.eu> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-29Merge tag 'sysctl-6.6-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull sysctl updates from Luis Chamberlain: "Long ago we set out to remove the kitchen sink on kernel/sysctl.c arrays and placings sysctls to their own sybsystem or file to help avoid merge conflicts. Matthew Wilcox pointed out though that if we're going to do that we might as well also *save* space while at it and try to remove the extra last sysctl entry added at the end of each array, a sentintel, instead of bloating the kernel by adding a new sentinel with each array moved. Doing that was not so trivial, and has required slowing down the moves of kernel/sysctl.c arrays and measuring the impact on size by each new move. The complex part of the effort to help reduce the size of each sysctl is being done by the patient work of el señor Don Joel Granados. A lot of this is truly painful code refactoring and testing and then trying to measure the savings of each move and removing the sentinels. Although Joel already has code which does most of this work, experience with sysctl moves in the past shows is we need to be careful due to the slew of odd build failures that are possible due to the amount of random Kconfig options sysctls use. To that end Joel's work is split by first addressing the major housekeeping needed to remove the sentinels, which is part of this merge request. The rest of the work to actually remove the sentinels will be done later in future kernel releases. The preliminary math is showing this will all help reduce the overall build time size of the kernel and run time memory consumed by the kernel by about ~64 bytes per array where we are able to remove each sentinel in the future. That also means there is no more bloating the kernel with the extra ~64 bytes per array moved as no new sentinels are created" * tag 'sysctl-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: sysctl: Use ctl_table_size as stopping criteria for list macro sysctl: SIZE_MAX->ARRAY_SIZE in register_net_sysctl vrf: Update to register_net_sysctl_sz networking: Update to register_net_sysctl_sz netfilter: Update to register_net_sysctl_sz ax.25: Update to register_net_sysctl_sz sysctl: Add size to register_net_sysctl function sysctl: Add size arg to __register_sysctl_init sysctl: Add size to register_sysctl sysctl: Add a size arg to __register_sysctl_table sysctl: Add size argument to init_header sysctl: Add ctl_table_size to ctl_table_header sysctl: Use ctl_table_header in list_for_each_table_entry sysctl: Prefer ctl_table_header in proc_sysctl
2023-08-15networking: Update to register_net_sysctl_szJoel Granados
Move from register_net_sysctl to register_net_sysctl_sz for all the networking related files. Do this while making sure to mirror the NULL assignments with a table_size of zero for the unprivileged users. We need to move to the new function in preparation for when we change SIZE_MAX to ARRAY_SIZE() in the register_net_sysctl macro. Failing to do so would erroneously allow ARRAY_SIZE() to be called on a pointer. We hold off the SIZE_MAX to ARRAY_SIZE change until we have migrated all the relevant net sysctl registering functions to register_net_sysctl_sz in subsequent commits. An additional size function was added to the following files in order to calculate the size of an array that is defined in another file: include/net/ipv6.h net/ipv6/icmp.c net/ipv6/route.c net/ipv6/sysctl_net_ipv6.c Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-08-09net: annotate data-races around sock->opsEric Dumazet
IPV6_ADDRFORM socket option is evil, because it can change sock->ops while other threads might read it. Same issue for sk->sk_family being set to AF_INET. Adding READ_ONCE() over sock->ops reads is needed for sockets that might be impacted by IPV6_ADDRFORM. Note that mptcp_is_tcpsk() can also overwrite sock->ops. Adding annotations for all sk->sk_family reads will require more patches :/ BUG: KCSAN: data-race in ____sys_sendmsg / do_ipv6_setsockopt write to 0xffff888109f24ca0 of 8 bytes by task 4470 on cpu 0: do_ipv6_setsockopt+0x2c5e/0x2ce0 net/ipv6/ipv6_sockglue.c:491 ipv6_setsockopt+0x57/0x130 net/ipv6/ipv6_sockglue.c:1012 udpv6_setsockopt+0x95/0xa0 net/ipv6/udp.c:1690 sock_common_setsockopt+0x61/0x70 net/core/sock.c:3663 __sys_setsockopt+0x1c3/0x230 net/socket.c:2273 __do_sys_setsockopt net/socket.c:2284 [inline] __se_sys_setsockopt net/socket.c:2281 [inline] __x64_sys_setsockopt+0x66/0x80 net/socket.c:2281 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff888109f24ca0 of 8 bytes by task 4469 on cpu 1: sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] ____sys_sendmsg+0x349/0x4c0 net/socket.c:2503 ___sys_sendmsg net/socket.c:2557 [inline] __sys_sendmmsg+0x263/0x500 net/socket.c:2643 __do_sys_sendmmsg net/socket.c:2672 [inline] __se_sys_sendmmsg net/socket.c:2669 [inline] __x64_sys_sendmmsg+0x57/0x60 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0xffffffff850e32b8 -> 0xffffffff850da890 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 4469 Comm: syz-executor.1 Not tainted 6.4.0-rc5-syzkaller-00313-g4c605260bc60 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230808135809.2300241-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-29net: add missing data-race annotations around sk->sk_peek_offEric Dumazet
sk_getsockopt() runs locklessly, thus we need to annotate the read of sk->sk_peek_off. While we are at it, add corresponding annotations to sk_set_peek_off() and unix_set_peek_off(). Fixes: b9bb53f3836f ("sock: convert sk_peek_offset functions to WRITE_ONCE") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-07-27af_unix: Terminate sun_path when bind()ing pathname socket.Kuniyuki Iwashima
kernel test robot reported slab-out-of-bounds access in strlen(). [0] Commit 06d4c8a80836 ("af_unix: Fix fortify_panic() in unix_bind_bsd().") removed unix_mkname_bsd() call in unix_bind_bsd(). If sunaddr->sun_path is not terminated by user and we don't enable CONFIG_INIT_STACK_ALL_ZERO=y, strlen() will do the out-of-bounds access during file creation. Let's go back to strlen()-with-sockaddr_storage way and pack all 108 trickiness into unix_mkname_bsd() with bold comments. [0]: BUG: KASAN: slab-out-of-bounds in strlen (lib/string.c:?) Read of size 1 at addr ffff000015492777 by task fortify_strlen_/168 CPU: 0 PID: 168 Comm: fortify_strlen_ Not tainted 6.5.0-rc1-00333-g3329b603ebba #16 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace (arch/arm64/kernel/stacktrace.c:235) show_stack (arch/arm64/kernel/stacktrace.c:242) dump_stack_lvl (lib/dump_stack.c:107) print_report (mm/kasan/report.c:365 mm/kasan/report.c:475) kasan_report (mm/kasan/report.c:590) __asan_report_load1_noabort (mm/kasan/report_generic.c:378) strlen (lib/string.c:?) getname_kernel (./include/linux/fortify-string.h:? fs/namei.c:226) kern_path_create (fs/namei.c:3926) unix_bind (net/unix/af_unix.c:1221 net/unix/af_unix.c:1324) __sys_bind (net/socket.c:1792) __arm64_sys_bind (net/socket.c:1801) invoke_syscall (arch/arm64/kernel/syscall.c:? arch/arm64/kernel/syscall.c:52) el0_svc_common (./include/linux/thread_info.h:127 arch/arm64/kernel/syscall.c:147) do_el0_svc (arch/arm64/kernel/syscall.c:189) el0_svc (./arch/arm64/include/asm/daifflags.h:28 arch/arm64/kernel/entry-common.c:133 arch/arm64/kernel/entry-common.c:144 arch/arm64/kernel/entry-common.c:648) el0t_64_sync_handler (arch/arm64/kernel/entry-common.c:?) el0t_64_sync (arch/arm64/kernel/entry.S:591) Allocated by task 168: kasan_set_track (mm/kasan/common.c:45 mm/kasan/common.c:52) kasan_save_alloc_info (mm/kasan/generic.c:512) __kasan_kmalloc (mm/kasan/common.c:383) __kmalloc (mm/slab_common.c:? mm/slab_common.c:998) unix_bind (net/unix/af_unix.c:257 net/unix/af_unix.c:1213 net/unix/af_unix.c:1324) __sys_bind (net/socket.c:1792) __arm64_sys_bind (net/socket.c:1801) invoke_syscall (arch/arm64/kernel/syscall.c:? arch/arm64/kernel/syscall.c:52) el0_svc_common (./include/linux/thread_info.h:127 arch/arm64/kernel/syscall.c:147) do_el0_svc (arch/arm64/kernel/syscall.c:189) el0_svc (./arch/arm64/include/asm/daifflags.h:28 arch/arm64/kernel/entry-common.c:133 arch/arm64/kernel/entry-common.c:144 arch/arm64/kernel/entry-common.c:648) el0t_64_sync_handler (arch/arm64/kernel/entry-common.c:?) el0t_64_sync (arch/arm64/kernel/entry.S:591) The buggy address belongs to the object at ffff000015492700 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 0 bytes to the right of allocated 119-byte region [ffff000015492700, ffff000015492777) The buggy address belongs to the physical page: page:00000000aeab52ba refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x55492 anon flags: 0x3fffc0000000200(slab|node=0|zone=0|lastcpupid=0xffff) page_type: 0xffffffff() raw: 03fffc0000000200 ffff0000084018c0 fffffc00003d0e00 0000000000000005 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff000015492600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff000015492680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff000015492700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 07 fc ^ ffff000015492780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff000015492800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 06d4c8a80836 ("af_unix: Fix fortify_panic() in unix_bind_bsd().") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/netdev/202307262110.659e5e8-oliver.sang@intel.com/ Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230726190828.47874-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-07-25af_unix: Fix fortify_panic() in unix_bind_bsd().Kuniyuki Iwashima
syzkaller found a bug in unix_bind_bsd() [0]. We can reproduce it by bind()ing a socket on a path with length 108. 108 is the size of sun_addr of struct sockaddr_un and is the maximum valid length for the pathname socket. When calling bind(), we use struct sockaddr_storage as the actual buffer size, so terminating sun_addr[108] with null is legitimate as done in unix_mkname_bsd(). However, strlen(sunaddr) for such a case causes fortify_panic() if CONFIG_FORTIFY_SOURCE=y. __fortify_strlen() has no idea about the actual buffer size and see the string as unterminated. Let's use strnlen() to allow sun_addr to be unterminated at 107. [0]: detected buffer overflow in __fortify_strlen kernel BUG at lib/string_helpers.c:1031! Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 255 Comm: syz-executor296 Not tainted 6.5.0-rc1-00330-g60cc1f7d0605 #4 Hardware name: linux,dummy-virt (DT) pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : fortify_panic+0x1c/0x20 lib/string_helpers.c:1030 lr : fortify_panic+0x1c/0x20 lib/string_helpers.c:1030 sp : ffff800089817af0 x29: ffff800089817af0 x28: ffff800089817b40 x27: 1ffff00011302f68 x26: 000000000000006e x25: 0000000000000012 x24: ffff800087e60140 x23: dfff800000000000 x22: ffff800089817c20 x21: ffff800089817c8e x20: 000000000000006c x19: ffff00000c323900 x18: ffff800086ab1630 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000001 x14: 1ffff00011302eb8 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000000000 x9 : 64a26b65474d2a00 x8 : 64a26b65474d2a00 x7 : 0000000000000001 x6 : 0000000000000001 x5 : ffff800089817438 x4 : ffff800086ac99e0 x3 : ffff800080f19e8c x2 : 0000000000000001 x1 : 0000000100000000 x0 : 000000000000002c Call trace: fortify_panic+0x1c/0x20 lib/string_helpers.c:1030 _Z16__fortify_strlenPKcU25pass_dynamic_object_size1 include/linux/fortify-string.h:217 [inline] unix_bind_bsd net/unix/af_unix.c:1212 [inline] unix_bind+0xba8/0xc58 net/unix/af_unix.c:1326 __sys_bind+0x1ac/0x248 net/socket.c:1792 __do_sys_bind net/socket.c:1803 [inline] __se_sys_bind net/socket.c:1801 [inline] __arm64_sys_bind+0x7c/0x94 net/socket.c:1801 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x134/0x240 arch/arm64/kernel/syscall.c:139 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:188 el0_svc+0x2c/0x7c arch/arm64/kernel/entry-common.c:647 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:665 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 Code: aa0003e1 d0000e80 91030000 97ffc91a (d4210000) Fixes: df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3") Reported-by: syzkaller <syzkaller@googlegroups.com> Suggested-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230724213425.22920-2-kuniyu@amazon.com Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-27net: scm: introduce and use scm_recv_unix helperAlexander Mikhalitsyn
Recently, our friends from bluetooth subsystem reported [1] that after commit 5e2ff6704a27 ("scm: add SO_PASSPIDFD and SCM_PIDFD") scm_recv() helper become unusable in kernel modules (because it uses unexported pidfd_prepare() API). We were aware of this issue and workarounded it in a hard way by commit 97154bcf4d1b ("af_unix: Kconfig: make CONFIG_UNIX bool"). But recently a new functionality was added in the scope of commit 817efd3cad74 ("Bluetooth: hci_sock: Forward credentials to monitor") and after that bluetooth can't be compiled as a kernel module. After some discussion in [1] we decided to split scm_recv() into two helpers, one won't support SCM_PIDFD (used for unix sockets), and another one will be completely the same as it was before commit 5e2ff6704a27 ("scm: add SO_PASSPIDFD and SCM_PIDFD"). Link: https://lore.kernel.org/lkml/CAJqdLrpFcga4n7wxBhsFqPQiN8PKFVr6U10fKcJ9W7AcZn+o6Q@mail.gmail.com/ [1] Fixes: 5e2ff6704a27 ("scm: add SO_PASSPIDFD and SCM_PIDFD") Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230627174314.67688-3-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-27Revert "af_unix: Call scm_recv() only after scm_set_cred()."Kuniyuki Iwashima
This reverts commit 3f5f118bb657f94641ea383c7c1b8c09a5d46ea2. Konrad reported that desktop environment below cannot be reached after commit 3f5f118bb657 ("af_unix: Call scm_recv() only after scm_set_cred().") - postmarketOS (Alpine Linux w/ musl 1.2.4) - busybox 1.36.1 - GNOME 44.1 - networkmanager 1.42.6 - openrc 0.47 Regarding to the warning of SO_PASSPIDFD, I'll post another patch to suppress it by skipping SCM_PIDFD if scm->pid == NULL in scm_pidfd_recv(). Reported-by: Konrad Dybcio <konradybcio@kernel.org> Link: https://lore.kernel.org/netdev/8c7f9abd-4f84-7296-2788-1e130d6304a0@kernel.org/ Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Gal Pressman <gal@nvidia.com> Link: https://lore.kernel.org/r/20230626205837.82086-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-24sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES)David Howells
Remove ->sendpage() and ->sendpage_locked(). sendmsg() with MSG_SPLICE_PAGES should be used instead. This allows multiple pages and multipage folios to be passed through. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> cc: linux-afs@lists.infradead.org cc: mptcp@lists.linux.dev cc: rds-devel@oss.oracle.com cc: tipc-discussion@lists.sourceforge.net cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-24af_unix: Call scm_recv() only after scm_set_cred().Kuniyuki Iwashima
syzkaller hit a WARN_ON_ONCE(!scm->pid) in scm_pidfd_recv(). In unix_stream_read_generic(), if there is no skb in the queue, we could bail out the do-while loop without calling scm_set_cred(): 1. No skb in the queue 2. sk is non-blocking or shutdown(sk, RCV_SHUTDOWN) is called concurrently or peer calls close() If the socket is configured with SO_PASSCRED or SO_PASSPIDFD, scm_recv() would populate cmsg with garbage. Let's not call scm_recv() unless there is skb to receive. WARNING: CPU: 1 PID: 3245 at include/net/scm.h:138 scm_pidfd_recv include/net/scm.h:138 [inline] WARNING: CPU: 1 PID: 3245 at include/net/scm.h:138 scm_recv.constprop.0+0x754/0x850 include/net/scm.h:177 Modules linked in: CPU: 1 PID: 3245 Comm: syz-executor.1 Not tainted 6.4.0-rc5-01219-gfa0e21fa4443 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:scm_pidfd_recv include/net/scm.h:138 [inline] RIP: 0010:scm_recv.constprop.0+0x754/0x850 include/net/scm.h:177 Code: 67 fd e9 55 fd ff ff e8 4a 70 67 fd e9 7f fd ff ff e8 40 70 67 fd e9 3e fb ff ff e8 36 70 67 fd e9 02 fd ff ff e8 8c 3a 20 fd <0f> 0b e9 fe fb ff ff e8 50 70 67 fd e9 2e f9 ff ff e8 46 70 67 fd RSP: 0018:ffffc90009af7660 EFLAGS: 00010216 RAX: 00000000000000a1 RBX: ffff888041e58a80 RCX: ffffc90003852000 RDX: 0000000000040000 RSI: ffffffff842675b4 RDI: 0000000000000007 RBP: ffffc90009af7810 R08: 0000000000000007 R09: 0000000000000013 R10: 00000000000000f8 R11: 0000000000000001 R12: ffffc90009af7db0 R13: 0000000000000000 R14: ffff888041e58a88 R15: 1ffff9200135eecc FS: 00007f6b7113f640(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6b7111de38 CR3: 0000000012a6e002 CR4: 0000000000770ee0 PKRU: 55555554 Call Trace: <TASK> unix_stream_read_generic+0x5fe/0x1f50 net/unix/af_unix.c:2830 unix_stream_recvmsg+0x194/0x1c0 net/unix/af_unix.c:2880 sock_recvmsg_nosec net/socket.c:1019 [inline] sock_recvmsg+0x188/0x1d0 net/socket.c:1040 ____sys_recvmsg+0x210/0x610 net/socket.c:2712 ___sys_recvmsg+0xff/0x190 net/socket.c:2754 do_recvmmsg+0x25d/0x6c0 net/socket.c:2848 __sys_recvmmsg net/socket.c:2927 [inline] __do_sys_recvmmsg net/socket.c:2950 [inline] __se_sys_recvmmsg net/socket.c:2943 [inline] __x64_sys_recvmmsg+0x224/0x290 net/socket.c:2943 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3f/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f6b71da2e5d Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 73 9f 1b 00 f7 d8 64 89 01 48 RSP: 002b:00007f6b7113ecc8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00000000004bc050 RCX: 00007f6b71da2e5d RDX: 0000000000000007 RSI: 0000000020006600 RDI: 000000000000000b RBP: 00000000004bc050 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000120 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f6b71e03530 R15: 0000000000000000 </TASK> Fixes: 5e2ff6704a27 ("scm: add SO_PASSPIDFD and SCM_PIDFD") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Alexander Mikhalitsyn <alexander@mihalicyn.com> Link: https://lore.kernel.org/r/20230622184351.91544-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-12af_unix: Kconfig: make CONFIG_UNIX boolAlexander Mikhalitsyn
Let's make CONFIG_UNIX a bool instead of a tristate. We've decided to do that during discussion about SCM_PIDFD patchset [1]. [1] https://lore.kernel.org/lkml/20230524081933.44dc8bea@kernel.org/ Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Leon Romanovsky <leon@kernel.org> Cc: David Ahern <dsahern@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Kees Cook <keescook@chromium.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Cc: Lennart Poettering <mzxreary@0pointer.de> Cc: Luca Boccassi <bluca@debian.org> Cc: linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org Cc: linux-arch@vger.kernel.org Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-06-12net: core: add getsockopt SO_PEERPIDFDAlexander Mikhalitsyn
Add SO_PEERPIDFD which allows to get pidfd of peer socket holder pidfd. This thing is direct analog of SO_PEERCRED which allows to get plain PID. Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Leon Romanovsky <leon@kernel.org> Cc: David Ahern <dsahern@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Kees Cook <keescook@chromium.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Cc: Lennart Poettering <mzxreary@0pointer.de> Cc: Luca Boccassi <bluca@debian.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Stanislav Fomichev <sdf@google.com> Cc: bpf@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org Cc: linux-arch@vger.kernel.org Reviewed-by: Christian Brauner <brauner@kernel.org> Acked-by: Stanislav Fomichev <sdf@google.com> Tested-by: Luca Boccassi <bluca@debian.org> Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-06-12scm: add SO_PASSPIDFD and SCM_PIDFDAlexander Mikhalitsyn
Implement SCM_PIDFD, a new type of CMSG type analogical to SCM_CREDENTIALS, but it contains pidfd instead of plain pid, which allows programmers not to care about PID reuse problem. We mask SO_PASSPIDFD feature if CONFIG_UNIX is not builtin because it depends on a pidfd_prepare() API which is not exported to the kernel modules. Idea comes from UAPI kernel group: https://uapi-group.org/kernel-features/ Big thanks to Christian Brauner and Lennart Poettering for productive discussions about this. Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Leon Romanovsky <leon@kernel.org> Cc: David Ahern <dsahern@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Kees Cook <keescook@chromium.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Cc: Lennart Poettering <mzxreary@0pointer.de> Cc: Luca Boccassi <bluca@debian.org> Cc: linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org Cc: linux-arch@vger.kernel.org Tested-by: Luca Boccassi <bluca@debian.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR. Conflicts: net/ipv4/raw.c 3632679d9e4f ("ipv{4,6}/raw: fix output xfrm lookup wrt protocol") c85be08fc4fa ("raw: Stop using RTO_ONLINK.") https://lore.kernel.org/all/20230525110037.2b532b83@canb.auug.org.au/ Adjacent changes: drivers/net/ethernet/freescale/fec_main.c 9025944fddfe ("net: fec: add dma_wmb to ensure correct descriptor values") 144470c88c5d ("net: fec: using the standard return codes when xdp xmit errors") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-23unix: Convert unix_stream_sendpage() to use MSG_SPLICE_PAGESDavid Howells
Convert unix_stream_sendpage() to use sendmsg() with MSG_SPLICE_PAGES rather than directly splicing in the pages itself. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells <dhowells@redhat.com> cc: Kuniyuki Iwashima <kuniyu@amazon.com> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-23af_unix: Support MSG_SPLICE_PAGESDavid Howells
Make AF_UNIX sendmsg() support MSG_SPLICE_PAGES, splicing in pages from the source iterator if possible and copying the data in otherwise. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells <dhowells@redhat.com> cc: Kuniyuki Iwashima <kuniyu@amazon.com> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-23net: Pass max frags into skb_append_pagefrags()David Howells
Pass the maximum number of fragments into skb_append_pagefrags() rather than using MAX_SKB_FRAGS so that it can be used from code that wants to specify sysctl_max_skb_frags. Signed-off-by: David Howells <dhowells@redhat.com> cc: David Ahern <dsahern@kernel.org> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-23bpf, sockmap: Pass skb ownership through read_skbJohn Fastabend
The read_skb hook calls consume_skb() now, but this means that if the recv_actor program wants to use the skb it needs to inc the ref cnt so that the consume_skb() doesn't kfree the sk_buff. This is problematic because in some error cases under memory pressure we may need to linearize the sk_buff from sk_psock_skb_ingress_enqueue(). Then we get this, skb_linearize() __pskb_pull_tail() pskb_expand_head() BUG_ON(skb_shared(skb)) Because we incremented users refcnt from sk_psock_verdict_recv() we hit the bug on with refcnt > 1 and trip it. To fix lets simply pass ownership of the sk_buff through the skb_read call. Then we can drop the consume from read_skb handlers and assume the verdict recv does any required kfree. Bug found while testing in our CI which runs in VMs that hit memory constraints rather regularly. William tested TCP read_skb handlers. [ 106.536188] ------------[ cut here ]------------ [ 106.536197] kernel BUG at net/core/skbuff.c:1693! [ 106.536479] invalid opcode: 0000 [#1] PREEMPT SMP PTI [ 106.536726] CPU: 3 PID: 1495 Comm: curl Not tainted 5.19.0-rc5 #1 [ 106.537023] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ArchLinux 1.16.0-1 04/01/2014 [ 106.537467] RIP: 0010:pskb_expand_head+0x269/0x330 [ 106.538585] RSP: 0018:ffffc90000138b68 EFLAGS: 00010202 [ 106.538839] RAX: 000000000000003f RBX: ffff8881048940e8 RCX: 0000000000000a20 [ 106.539186] RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff8881048940e8 [ 106.539529] RBP: ffffc90000138be8 R08: 00000000e161fd1a R09: 0000000000000000 [ 106.539877] R10: 0000000000000018 R11: 0000000000000000 R12: ffff8881048940e8 [ 106.540222] R13: 0000000000000003 R14: 0000000000000000 R15: ffff8881048940e8 [ 106.540568] FS: 00007f277dde9f00(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000 [ 106.540954] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 106.541227] CR2: 00007f277eeede64 CR3: 000000000ad3e000 CR4: 00000000000006e0 [ 106.541569] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 106.541915] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 106.542255] Call Trace: [ 106.542383] <IRQ> [ 106.542487] __pskb_pull_tail+0x4b/0x3e0 [ 106.542681] skb_ensure_writable+0x85/0xa0 [ 106.542882] sk_skb_pull_data+0x18/0x20 [ 106.543084] bpf_prog_b517a65a242018b0_bpf_skskb_http_verdict+0x3a9/0x4aa9 [ 106.543536] ? migrate_disable+0x66/0x80 [ 106.543871] sk_psock_verdict_recv+0xe2/0x310 [ 106.544258] ? sk_psock_write_space+0x1f0/0x1f0 [ 106.544561] tcp_read_skb+0x7b/0x120 [ 106.544740] tcp_data_queue+0x904/0xee0 [ 106.544931] tcp_rcv_established+0x212/0x7c0 [ 106.545142] tcp_v4_do_rcv+0x174/0x2a0 [ 106.545326] tcp_v4_rcv+0xe70/0xf60 [ 106.545500] ip_protocol_deliver_rcu+0x48/0x290 [ 106.545744] ip_local_deliver_finish+0xa7/0x150 Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()") Reported-by: William Findlay <will@isovalent.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: William Findlay <will@isovalent.com> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20230523025618.113937-2-john.fastabend@gmail.com
2023-05-10af_unix: Fix data races around sk->sk_shutdown.Kuniyuki Iwashima
KCSAN found a data race around sk->sk_shutdown where unix_release_sock() and unix_shutdown() update it under unix_state_lock(), OTOH unix_poll() and unix_dgram_poll() read it locklessly. We need to annotate the writes and reads with WRITE_ONCE() and READ_ONCE(). BUG: KCSAN: data-race in unix_poll / unix_release_sock write to 0xffff88800d0f8aec of 1 bytes by task 264 on cpu 0: unix_release_sock+0x75c/0x910 net/unix/af_unix.c:631 unix_release+0x59/0x80 net/unix/af_unix.c:1042 __sock_release+0x7d/0x170 net/socket.c:653 sock_close+0x19/0x30 net/socket.c:1397 __fput+0x179/0x5e0 fs/file_table.c:321 ____fput+0x15/0x20 fs/file_table.c:349 task_work_run+0x116/0x1a0 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x174/0x180 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:297 do_syscall_64+0x4b/0x90 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x72/0xdc read to 0xffff88800d0f8aec of 1 bytes by task 222 on cpu 1: unix_poll+0xa3/0x2a0 net/unix/af_unix.c:3170 sock_poll+0xcf/0x2b0 net/socket.c:1385 vfs_poll include/linux/poll.h:88 [inline] ep_item_poll.isra.0+0x78/0xc0 fs/eventpoll.c:855 ep_send_events fs/eventpoll.c:1694 [inline] ep_poll fs/eventpoll.c:1823 [inline] do_epoll_wait+0x6c4/0xea0 fs/eventpoll.c:2258 __do_sys_epoll_wait fs/eventpoll.c:2270 [inline] __se_sys_epoll_wait fs/eventpoll.c:2265 [inline] __x64_sys_epoll_wait+0xcc/0x190 fs/eventpoll.c:2265 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc value changed: 0x00 -> 0x03 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 222 Comm: dbus-broker Not tainted 6.3.0-rc7-02330-gca6270c12e20 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Fixes: 3c73419c09a5 ("af_unix: fix 'poll for write'/ connected DGRAM sockets") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Michal Kubiak <michal.kubiak@intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-10af_unix: Fix a data race of sk->sk_receive_queue->qlen.Kuniyuki Iwashima
KCSAN found a data race of sk->sk_receive_queue->qlen where recvmsg() updates qlen under the queue lock and sendmsg() checks qlen under unix_state_sock(), not the queue lock, so the reader side needs READ_ONCE(). BUG: KCSAN: data-race in __skb_try_recv_from_queue / unix_wait_for_peer write (marked) to 0xffff888019fe7c68 of 4 bytes by task 49792 on cpu 0: __skb_unlink include/linux/skbuff.h:2347 [inline] __skb_try_recv_from_queue+0x3de/0x470 net/core/datagram.c:197 __skb_try_recv_datagram+0xf7/0x390 net/core/datagram.c:263 __unix_dgram_recvmsg+0x109/0x8a0 net/unix/af_unix.c:2452 unix_dgram_recvmsg+0x94/0xa0 net/unix/af_unix.c:2549 sock_recvmsg_nosec net/socket.c:1019 [inline] ____sys_recvmsg+0x3a3/0x3b0 net/socket.c:2720 ___sys_recvmsg+0xc8/0x150 net/socket.c:2764 do_recvmmsg+0x182/0x560 net/socket.c:2858 __sys_recvmmsg net/socket.c:2937 [inline] __do_sys_recvmmsg net/socket.c:2960 [inline] __se_sys_recvmmsg net/socket.c:2953 [inline] __x64_sys_recvmmsg+0x153/0x170 net/socket.c:2953 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc read to 0xffff888019fe7c68 of 4 bytes by task 49793 on cpu 1: skb_queue_len include/linux/skbuff.h:2127 [inline] unix_recvq_full net/unix/af_unix.c:229 [inline] unix_wait_for_peer+0x154/0x1a0 net/unix/af_unix.c:1445 unix_dgram_sendmsg+0x13bc/0x14b0 net/unix/af_unix.c:2048 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg+0x148/0x160 net/socket.c:747 ____sys_sendmsg+0x20e/0x620 net/socket.c:2503 ___sys_sendmsg+0xc6/0x140 net/socket.c:2557 __sys_sendmmsg+0x11d/0x370 net/socket.c:2643 __do_sys_sendmmsg net/socket.c:2672 [inline] __se_sys_sendmmsg net/socket.c:2669 [inline] __x64_sys_sendmmsg+0x58/0x70 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc value changed: 0x0000000b -> 0x00000001 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 49793 Comm: syz-executor.0 Not tainted 6.3.0-rc7-02330-gca6270c12e20 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Michal Kubiak <michal.kubiak@intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-17af_unix: annotate lockless accesses to sk->sk_errEric Dumazet
unix_poll() and unix_dgram_poll() read sk->sk_err without any lock held. Add relevant READ_ONCE()/WRITE_ONCE() annotations. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Documentation/bpf/bpf_devel_QA.rst b7abcd9c656b ("bpf, doc: Link to submitting-patches.rst for general patch submission info") d56b0c461d19 ("bpf, docs: Fix link to netdev-FAQ target") https://lore.kernel.org/all/20230307095812.236eb1be@canb.auug.org.au/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-08af_unix: fix struct pid leaks in OOB supportEric Dumazet
syzbot reported struct pid leak [1]. Issue is that queue_oob() calls maybe_add_creds() which potentially holds a reference on a pid. But skb->destructor is not set (either directly or by calling unix_scm_to_skb()) This means that subsequent kfree_skb() or consume_skb() would leak this reference. In this fix, I chose to fully support scm even for the OOB message. [1] BUG: memory leak unreferenced object 0xffff8881053e7f80 (size 128): comm "syz-executor242", pid 5066, jiffies 4294946079 (age 13.220s) hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff812ae26a>] alloc_pid+0x6a/0x560 kernel/pid.c:180 [<ffffffff812718df>] copy_process+0x169f/0x26c0 kernel/fork.c:2285 [<ffffffff81272b37>] kernel_clone+0xf7/0x610 kernel/fork.c:2684 [<ffffffff812730cc>] __do_sys_clone+0x7c/0xb0 kernel/fork.c:2825 [<ffffffff849ad699>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [<ffffffff849ad699>] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 [<ffffffff84a0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: 314001f0bf92 ("af_unix: Add OOB support") Reported-by: syzbot+7699d9e5635c10253a27@syzkaller.appspotmail.com Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Rao Shoaib <rao.shoaib@oracle.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230307164530.771896-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-08net: reclaim skb->scm_io_uring bitEric Dumazet
Commit 0091bfc81741 ("io_uring/af_unix: defer registered files gc to io_uring release") added one bit to struct sk_buff. This structure is critical for networking, and we try very hard to not add bloat on it, unless absolutely required. For instance, we can use a specific destructor as a wrapper around unix_destruct_scm(), to identify skbs that unix_gc() has to special case. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Pavel Begunkov <asml.silence@gmail.com> Cc: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Cc: Jens Axboe <axboe@kernel.dk> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-03bpf, sockmap: Fix an infinite loop error when len is 0 in ↵Liu Jian
tcp_bpf_recvmsg_parser() When the buffer length of the recvmsg system call is 0, we got the flollowing soft lockup problem: watchdog: BUG: soft lockup - CPU#3 stuck for 27s! [a.out:6149] CPU: 3 PID: 6149 Comm: a.out Kdump: loaded Not tainted 6.2.0+ #30 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 RIP: 0010:remove_wait_queue+0xb/0xc0 Code: 5e 41 5f c3 cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 1f 44 00 00 41 57 <41> 56 41 55 41 54 55 48 89 fd 53 48 89 f3 4c 8d 6b 18 4c 8d 73 20 RSP: 0018:ffff88811b5978b8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff88811a7d3780 RCX: ffffffffb7a4d768 RDX: dffffc0000000000 RSI: ffff88811b597908 RDI: ffff888115408040 RBP: 1ffff110236b2f1b R08: 0000000000000000 R09: ffff88811a7d37e7 R10: ffffed10234fa6fc R11: 0000000000000001 R12: ffff88811179b800 R13: 0000000000000001 R14: ffff88811a7d38a8 R15: ffff88811a7d37e0 FS: 00007f6fb5398740(0000) GS:ffff888237180000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000000 CR3: 000000010b6ba002 CR4: 0000000000370ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> tcp_msg_wait_data+0x279/0x2f0 tcp_bpf_recvmsg_parser+0x3c6/0x490 inet_recvmsg+0x280/0x290 sock_recvmsg+0xfc/0x120 ____sys_recvmsg+0x160/0x3d0 ___sys_recvmsg+0xf0/0x180 __sys_recvmsg+0xea/0x1a0 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc The logic in tcp_bpf_recvmsg_parser is as follows: msg_bytes_ready: copied = sk_msg_recvmsg(sk, psock, msg, len, flags); if (!copied) { wait data; goto msg_bytes_ready; } In this case, "copied" always is 0, the infinite loop occurs. According to the Linux system call man page, 0 should be returned in this case. Therefore, in tcp_bpf_recvmsg_parser(), if the length is 0, directly return. Also modify several other functions with the same problem. Fixes: 1f5be6b3b063 ("udp: Implement udp_bpf_recvmsg() for sockmap") Fixes: 9825d866ce0d ("af_unix: Implement unix_dgram_bpf_recvmsg()") Fixes: c5d2177a72a1 ("bpf, sockmap: Fix race in ingress receive verdict with redirect to self") Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: Liu Jian <liujian56@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Cc: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20230303080946.1146638-1-liujian56@huawei.com
2023-02-21Merge tag 'net-next-6.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
2023-01-27net: add missing includes of linux/splice.hJakub Kicinski
Number of files depend on linux/splice.h getting included by linux/skbuff.h which soon will no longer be the case. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-18fs: port vfs_*() helpers to struct mnt_idmapChristian Brauner
Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-16unix: Improve locking scheme in unix_show_fdinfo()Kirill Tkhai
After switching to TCP_ESTABLISHED or TCP_LISTEN sk_state, alive SOCK_STREAM and SOCK_SEQPACKET sockets can't change it anymore (since commit 3ff8bff704f4 "unix: Fix race in SOCK_SEQPACKET's unix_dgram_sendmsg()"). Thus, we do not need to take lock here. Signed-off-by: Kirill Tkhai <tkhai@ya.ru> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-15unix: Fix race in SOCK_SEQPACKET's unix_dgram_sendmsg()Kirill Tkhai
There is a race resulting in alive SOCK_SEQPACKET socket may change its state from TCP_ESTABLISHED to TCP_CLOSE: unix_release_sock(peer) unix_dgram_sendmsg(sk) sock_orphan(peer) sock_set_flag(peer, SOCK_DEAD) sock_alloc_send_pskb() if !(sk->sk_shutdown & SEND_SHUTDOWN) OK if sock_flag(peer, SOCK_DEAD) sk->sk_state = TCP_CLOSE sk->sk_shutdown = SHUTDOWN_MASK After that socket sk remains almost normal: it is able to connect, listen, accept and recvmsg, while it can't sendmsg. Since this is the only possibility for alive SOCK_SEQPACKET to change the state in such way, we should better fix this strange and potentially danger corner case. Note, that we will return EPIPE here like this is normally done in sock_alloc_send_pskb(). Originally used ECONNREFUSED looks strange, since it's strange to return a specific retval in dependence of race in kernel, when user can't affect on this. Also, move TCP_CLOSE assignment for SOCK_DGRAM sockets under state lock to fix race with unix_dgram_connect(): unix_dgram_connect(other) unix_dgram_sendmsg(sk) unix_peer(sk) = NULL unix_state_unlock(sk) unix_state_double_lock(sk, other) sk->sk_state = TCP_ESTABLISHED unix_peer(sk) = other unix_state_double_unlock(sk, other) sk->sk_state = TCP_CLOSED This patch fixes both of these races. Fixes: 83301b5367a9 ("af_unix: Set TCP_ESTABLISHED for datagram sockets too") Signed-off-by: Kirill Tkhai <tkhai@ya.ru> Link: https://lore.kernel.org/r/135fda25-22d5-837a-782b-ceee50e19844@ya.ru Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-12-12af_unix: call proto_unregister() in the error path in af_unix_init()Yang Yingliang
If register unix_stream_proto returns error, unix_dgram_proto needs be unregistered. Fixes: 94531cfcbe79 ("af_unix: Add unix_stream_proto for sockmap") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-12-01af_unix: Get user_ns from in_skb in unix_diag_get_exact().Kuniyuki Iwashima
Wei Chen reported a NULL deref in sk_user_ns() [0][1], and Paolo diagnosed the root cause: in unix_diag_get_exact(), the newly allocated skb does not have sk. [2] We must get the user_ns from the NETLINK_CB(in_skb).sk and pass it to sk_diag_fill(). [0]: BUG: kernel NULL pointer dereference, address: 0000000000000270 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 12bbce067 P4D 12bbce067 PUD 12bc40067 PMD 0 Oops: 0000 [#1] PREEMPT SMP CPU: 0 PID: 27942 Comm: syz-executor.0 Not tainted 6.1.0-rc5-next-20221118 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-48-gd9c812dda519-prebuilt.qemu.org 04/01/2014 RIP: 0010:sk_user_ns include/net/sock.h:920 [inline] RIP: 0010:sk_diag_dump_uid net/unix/diag.c:119 [inline] RIP: 0010:sk_diag_fill+0x77d/0x890 net/unix/diag.c:170 Code: 89 ef e8 66 d4 2d fd c7 44 24 40 00 00 00 00 49 8d 7c 24 18 e8 54 d7 2d fd 49 8b 5c 24 18 48 8d bb 70 02 00 00 e8 43 d7 2d fd <48> 8b 9b 70 02 00 00 48 8d 7b 10 e8 33 d7 2d fd 48 8b 5b 10 48 8d RSP: 0018:ffffc90000d67968 EFLAGS: 00010246 RAX: ffff88812badaa48 RBX: 0000000000000000 RCX: ffffffff840d481d RDX: 0000000000000465 RSI: 0000000000000000 RDI: 0000000000000270 RBP: ffffc90000d679a8 R08: 0000000000000277 R09: 0000000000000000 R10: 0001ffffffffffff R11: 0001c90000d679a8 R12: ffff88812ac03800 R13: ffff88812c87c400 R14: ffff88812ae42210 R15: ffff888103026940 FS: 00007f08b4e6f700(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000270 CR3: 000000012c58b000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> unix_diag_get_exact net/unix/diag.c:285 [inline] unix_diag_handler_dump+0x3f9/0x500 net/unix/diag.c:317 __sock_diag_cmd net/core/sock_diag.c:235 [inline] sock_diag_rcv_msg+0x237/0x250 net/core/sock_diag.c:266 netlink_rcv_skb+0x13e/0x250 net/netlink/af_netlink.c:2564 sock_diag_rcv+0x24/0x40 net/core/sock_diag.c:277 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline] netlink_unicast+0x5e9/0x6b0 net/netlink/af_netlink.c:1356 netlink_sendmsg+0x739/0x860 net/netlink/af_netlink.c:1932 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] ____sys_sendmsg+0x38f/0x500 net/socket.c:2476 ___sys_sendmsg net/socket.c:2530 [inline] __sys_sendmsg+0x197/0x230 net/socket.c:2559 __do_sys_sendmsg net/socket.c:2568 [inline] __se_sys_sendmsg net/socket.c:2566 [inline] __x64_sys_sendmsg+0x42/0x50 net/socket.c:2566 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x4697f9 Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f08b4e6ec48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000077bf80 RCX: 00000000004697f9 RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003 RBP: 00000000004d29e9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000077bf80 R13: 0000000000000000 R14: 000000000077bf80 R15: 00007ffdb36bc6c0 </TASK> Modules linked in: CR2: 0000000000000270 [1]: https://lore.kernel.org/netdev/CAO4mrfdvyjFpokhNsiwZiP-wpdSD0AStcJwfKcKQdAALQ9_2Qw@mail.gmail.com/ [2]: https://lore.kernel.org/netdev/e04315e7c90d9a75613f3993c2baf2d344eef7eb.camel@redhat.com/ Fixes: cae9910e7344 ("net: Add UNIX_DIAG_UID to Netlink UNIX socket diagnostics.") Reported-by: syzbot <syzkaller@googlegroups.com> Reported-by: Wei Chen <harperchen1110@gmail.com> Diagnosed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-10-28net: remove SOCK_SUPPORT_ZC from sockmapPavel Begunkov
sockmap replaces ->sk_prot with its own callbacks, we should remove SOCK_SUPPORT_ZC as the new proto doesn't support msghdr::ubuf_info. Cc: <stable@vger.kernel.org> # 6.0 Reported-by: Jakub Kicinski <kuba@kernel.org> Fixes: e993ffe3da4bc ("net: flag sockets supporting msghdr originated zerocopy") Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-16Merge tag 'random-6.1-rc1-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/crng/random Pull more random number generator updates from Jason Donenfeld: "This time with some large scale treewide cleanups. The intent of this pull is to clean up the way callers fetch random integers. The current rules for doing this right are: - If you want a secure or an insecure random u64, use get_random_u64() - If you want a secure or an insecure random u32, use get_random_u32() The old function prandom_u32() has been deprecated for a while now and is just a wrapper around get_random_u32(). Same for get_random_int(). - If you want a secure or an insecure random u16, use get_random_u16() - If you want a secure or an insecure random u8, use get_random_u8() - If you want secure or insecure random bytes, use get_random_bytes(). The old function prandom_bytes() has been deprecated for a while now and has long been a wrapper around get_random_bytes() - If you want a non-uniform random u32, u16, or u8 bounded by a certain open interval maximum, use prandom_u32_max() I say "non-uniform", because it doesn't do any rejection sampling or divisions. Hence, it stays within the prandom_*() namespace, not the get_random_*() namespace. I'm currently investigating a "uniform" function for 6.2. We'll see what comes of that. By applying these rules uniformly, we get several benefits: - By using prandom_u32_max() with an upper-bound that the compiler can prove at compile-time is ≤65536 or ≤256, internally get_random_u16() or get_random_u8() is used, which wastes fewer batched random bytes, and hence has higher throughput. - By using prandom_u32_max() instead of %, when the upper-bound is not a constant, division is still avoided, because prandom_u32_max() uses a faster multiplication-based trick instead. - By using get_random_u16() or get_random_u8() in cases where the return value is intended to indeed be a u16 or a u8, we waste fewer batched random bytes, and hence have higher throughput. This series was originally done by hand while I was on an airplane without Internet. Later, Kees and I worked on retroactively figuring out what could be done with Coccinelle and what had to be done manually, and then we split things up based on that. So while this touches a lot of files, the actual amount of code that's hand fiddled is comfortably small" * tag 'random-6.1-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: prandom: remove unused functions treewide: use get_random_bytes() when possible treewide: use get_random_u32() when possible treewide: use get_random_{u8,u16}() when possible, part 2 treewide: use get_random_{u8,u16}() when possible, part 1 treewide: use prandom_u32_max() when possible, part 2 treewide: use prandom_u32_max() when possible, part 1