summaryrefslogtreecommitdiff
path: root/net/l2tp
AgeCommit message (Collapse)Author
2020-07-30l2tp: improve API documentation in l2tp_core.hTom Parkin
* Improve the description of the key l2tp subsystem data structures. * Add high-level description of the main APIs for interacting with l2tp core. * Add documentation for the l2tp netlink session command callbacks. * Document the session pseudowire callbacks. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-30l2tp: tweak exports for l2tp_recv_common and l2tp_ioctlTom Parkin
All of the l2tp subsystem's exported symbols are exported using EXPORT_SYMBOL_GPL, except for l2tp_recv_common and l2tp_ioctl. These functions alone are not useful without the rest of the l2tp infrastructure, so there's no practical benefit to these symbols using a different export policy. Change these exports to use EXPORT_SYMBOL_GPL for consistency with the rest of l2tp. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-30l2tp: remove build_header callback in struct l2tp_sessionTom Parkin
The structure of an L2TP data packet header varies depending on the version of the L2TP protocol being used. struct l2tp_session used to have a build_header callback to abstract this difference away. It's clearer to simply choose the correct function to use when building the data packet (and we save on the function pointer in the session structure). This approach does mean dereferencing the parent tunnel structure in order to determine the tunnel version, but we're doing that in the transmit path in any case. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-30l2tp: return void from l2tp_session_deleteTom Parkin
l2tp_session_delete is used to schedule a session instance for deletion. The function itself always returns zero, and none of its direct callers check its return value, so have the function return void. This change de-facto changes the l2tp netlink session_delete callback prototype since all pseudowires currently use l2tp_session_delete for their implementation of that operation. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-30l2tp: don't export tunnel and session free functionsTom Parkin
Tunnel and session instances are reference counted, and shouldn't be directly freed by pseudowire code. Rather than exporting l2tp_tunnel_free and l2tp_session_free, make them private to l2tp_core.c, and export the refcount functions instead. In order to do this, the refcount functions cannot be declared as inline. Since the codepaths which take and drop tunnel and session references are not directly in the datapath this shouldn't cause performance issues. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-30l2tp: don't export __l2tp_session_unhashTom Parkin
When __l2tp_session_unhash was first added it was used outside of l2tp_core.c, but that's no longer the case. As such, there's no longer a need to export the function. Make it private inside l2tp_core.c, and relocate it to avoid having to declare the function prototype in l2tp_core.h. Since the function is no longer used outside l2tp_core.c, remove the "__" prefix since we don't need to indicate anything special about its expected use to callers. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24l2tp: WARN_ON rather than BUG_ON in l2tp_session_freeTom Parkin
l2tp_session_free called BUG_ON if the tunnel magic feather value wasn't correct. The intent of this was to catch lifetime bugs; for example early tunnel free due to incorrect use of reference counts. Since the tunnel magic feather being wrong indicates either early free or structure corruption, we can avoid doing more damage by simply leaving the tunnel structure alone. If the tunnel refcount isn't dropped when it should be, the tunnel instance will remain in the kernel, resulting in the tunnel structure and socket leaking. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24l2tp: remove BUG_ON refcount value in l2tp_session_freeTom Parkin
l2tp_session_free is only called by l2tp_session_dec_refcount when the reference count reaches zero, so it's of limited value to validate the reference count value in l2tp_session_free itself. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24l2tp: WARN_ON rather than BUG_ON in l2tp_session_queue_purgeTom Parkin
l2tp_session_queue_purge is used during session shutdown to drop any skbs queued for reordering purposes according to L2TP dataplane rules. The BUG_ON in this function checks the session magic feather in an attempt to catch lifetime bugs. Rather than crashing the kernel with a BUG_ON, we can simply WARN_ON and refuse to do anything more -- in the worst case this could result in a leak. However this is highly unlikely given that the session purge only occurs from codepaths which have obtained the session by means of a lookup via. the parent tunnel and which check the session "dead" flag to protect against shutdown races. While we're here, have l2tp_session_queue_purge return void rather than an integer, since neither of the callsites checked the return value. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24l2tp: don't BUG_ON seqfile checks in l2tp_pppTom Parkin
checkpatch advises that WARN_ON and recovery code are preferred over BUG_ON which crashes the kernel. l2tp_ppp has a BUG_ON check of struct seq_file's private pointer in pppol2tp_seq_start prior to accessing data through that pointer. Rather than crashing, we can simply bail out early and return NULL in order to terminate the seq file processing in much the same way as we do when reaching the end of tunnel/session instances to render. Retain a WARN_ON to help trace possible bugs in this area. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24l2tp: don't BUG_ON session magic checks in l2tp_pppTom Parkin
checkpatch advises that WARN_ON and recovery code are preferred over BUG_ON which crashes the kernel. l2tp_ppp.c's BUG_ON checks of the l2tp session structure's "magic" field occur in code paths where it's reasonably easy to recover: * In the case of pppol2tp_sock_to_session, we can return NULL and the caller will bail out appropriately. There is no change required to any of the callsites of this function since they already handle pppol2tp_sock_to_session returning NULL. * In the case of pppol2tp_session_destruct we can just avoid decrementing the reference count on the suspect session structure. In the worst case scenario this results in a memory leak, which is preferable to a crash. Convert these uses of BUG_ON to WARN_ON accordingly. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24l2tp: remove BUG_ON in l2tp_tunnel_closeallTom Parkin
l2tp_tunnel_closeall is only called from l2tp_core.c, and it's easy to statically analyse the code path calling it to validate that it should never be passed a NULL tunnel pointer. Having a BUG_ON checking the tunnel pointer triggers a checkpatch warning. Since the BUG_ON is of no value, remove it to avoid the warning. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24l2tp: remove BUG_ON in l2tp_session_queue_purgeTom Parkin
l2tp_session_queue_purge is only called from l2tp_core.c, and it's easy to statically analyse the code paths calling it to validate that it should never be passed a NULL session pointer. Having a BUG_ON checking the session pointer triggers a checkpatch warning. Since the BUG_ON is of no value, remove it to avoid the warning. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24l2tp: WARN_ON rather than BUG_ON in l2tp_dfs_seq_startTom Parkin
l2tp_dfs_seq_start had a BUG_ON to catch a possible programming error in l2tp_dfs_seq_open. Since we can easily bail out of l2tp_dfs_seq_start, prefer to do that and flag the error with a WARN_ON rather than crashing the kernel. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24l2tp: avoid multiple assignmentsTom Parkin
checkpatch warns about multiple assignments. Update l2tp accordingly. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24net: pass a sockptr_t into ->setsockoptChristoph Hellwig
Rework the remaining setsockopt code to pass a sockptr_t instead of a plain user pointer. This removes the last remaining set_fs(KERNEL_DS) outside of architecture specific code. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154] Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-23l2tp: cleanup kzalloc callsTom Parkin
Passing "sizeof(struct blah)" in kzalloc calls is less readable, potentially prone to future bugs if the type of the pointer is changed, and triggers checkpatch warnings. Tweak the kzalloc calls in l2tp which use this form to avoid the warning. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-23l2tp: cleanup netlink tunnel create address handlingTom Parkin
When creating an L2TP tunnel using the netlink API, userspace must either pass a socket FD for the tunnel to use (for managed tunnels), or specify the tunnel source/destination address (for unmanaged tunnels). Since source/destination addresses may be AF_INET or AF_INET6, the l2tp netlink code has conditionally compiled blocks to support IPv6. Rather than embedding these directly into l2tp_nl_cmd_tunnel_create (where it makes the code difficult to read and confuses checkpatch to boot) split the handling of address-related attributes into a separate function. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-23l2tp: cleanup netlink send of tunnel address informationTom Parkin
l2tp_nl_tunnel_send has conditionally compiled code to support AF_INET6, which makes the code difficult to follow and triggers checkpatch warnings. Split the code out into functions to handle the AF_INET v.s. AF_INET6 cases, which both improves readability and resolves the checkpatch warnings. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-23l2tp: check socket address type in l2tp_dfs_seq_tunnel_showTom Parkin
checkpatch warns about indentation and brace balancing around the conditionally compiled code for AF_INET6 support in l2tp_dfs_seq_tunnel_show. By adding another check on the socket address type we can make the code more readable while removing the checkpatch warning. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-23l2tp: cleanup unnecessary braces in if statementsTom Parkin
These checks are all simple and don't benefit from extra braces to clarify intent. Remove them for easier-reading code. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-23l2tp: cleanup comparisons to NULLTom Parkin
checkpatch warns about comparisons to NULL, e.g. CHECK: Comparison to NULL could be written "!rt" #474: FILE: net/l2tp/l2tp_ip.c:474: + if (rt == NULL) { These sort of comparisons are generally clearer and more readable the way checkpatch suggests, so update l2tp accordingly. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-22l2tp: avoid precidence issues in L2TP_SKB_CB macroTom Parkin
checkpatch warned about the L2TP_SKB_CB macro's use of its argument: add braces to avoid the problem. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-22l2tp: line-break long function prototypesTom Parkin
In l2tp_core.c both l2tp_tunnel_create and l2tp_session_create take quite a number of arguments and have a correspondingly long prototype. This is both quite difficult to scan visually, and triggers checkpatch warnings. Add a line break to make these function prototypes more readable. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-22l2tp: prefer seq_puts for unformatted outputTom Parkin
checkpatch warns about use of seq_printf where seq_puts would do. Modify l2tp_debugfs accordingly. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-22l2tp: prefer using BIT macroTom Parkin
Use BIT(x) rather than (1<<x), reported by checkpatch.pl. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-22l2tp: add identifier name in function pointer prototypeTom Parkin
Reported by checkpatch: "WARNING: function definition argument 'struct sock *' should also have an identifier name" Add an identifier name to help document the prototype. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-22l2tp: cleanup suspect code indentTom Parkin
l2tp_core has conditionally compiled code in l2tp_xmit_skb for IPv6 support. The structure of this code triggered a checkpatch warning due to incorrect indentation. Fix up the indentation to address the checkpatch warning. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-22l2tp: cleanup wonky alignment of line-broken function callsTom Parkin
Arguments should be aligned with the function call open parenthesis as per checkpatch. Tweak some function calls which were not aligned correctly. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-22l2tp: cleanup difficult-to-read line breaksTom Parkin
Some l2tp code had line breaks which made the code more difficult to read. These were originally motivated by the 80-character line width coding guidelines, but were actually a negative from the perspective of trying to follow the code. Remove these linebreaks for clearer code, even if we do exceed 80 characters in width in some places. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-22l2tp: cleanup commentsTom Parkin
Modify some l2tp comments to better adhere to kernel coding style, as reported by checkpatch.pl. Add descriptive comments for the l2tp per-net spinlocks to document their use. Fix an incorrect comment in l2tp_recv_common: RFC2661 section 5.4 states that: "The LNS controls enabling and disabling of sequence numbers by sending a data message with or without sequence numbers present at any time during the life of a session." l2tp handles this correctly in l2tp_recv_common, but the comment around the code was incorrect and confusing. Fix up the comment accordingly. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-22l2tp: cleanup whitespace useTom Parkin
Fix up various whitespace issues as reported by checkpatch.pl: * remove spaces around operators where appropriate, * add missing blank lines following declarations, * remove multiple blank lines, or trailing blank lines at the end of functions. Signed-off-by: Tom Parkin <tparkin@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19net/ipv6: remove compat_ipv6_{get,set}sockoptChristoph Hellwig
Handle the few cases that need special treatment in-line using in_compat_syscall(). This also removes all the now unused compat_{get,set}sockopt methods. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19net/ipv4: remove compat_ip_{get,set}sockoptChristoph Hellwig
Handle the few cases that need special treatment in-line using in_compat_syscall(). Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19net: remove compat_sock_common_{get,set}sockoptChristoph Hellwig
Add the compat handling to sock_common_{get,set}sockopt instead, keyed of in_compat_syscall(). This allow to remove the now unused ->compat_{get,set}sockopt methods from struct proto_ops. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
All conflicts seemed rather trivial, with some guidance from Saeed Mameed on the tc_ct.c one. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-08l2tp: remove skb_dst_set() from l2tp_xmit_skb()Xin Long
In the tx path of l2tp, l2tp_xmit_skb() calls skb_dst_set() to set skb's dst. However, it will eventually call inet6_csk_xmit() or ip_queue_xmit() where skb's dst will be overwritten by: skb_dst_set_noref(skb, dst); without releasing the old dst in skb. Then it causes dst/dev refcnt leak: unregister_netdevice: waiting for eth0 to become free. Usage count = 1 This can be reproduced by simply running: # modprobe l2tp_eth && modprobe l2tp_ip # sh ./tools/testing/selftests/net/l2tp.sh So before going to inet6_csk_xmit() or ip_queue_xmit(), skb's dst should be dropped. This patch is to fix it by removing skb_dst_set() from l2tp_xmit_skb() and moving skb_dst_drop() into l2tp_xmit_core(). Fixes: 3557baabf280 ("[L2TP]: PPP over L2TP driver core") Reported-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: James Chapman <jchapman@katalix.com> Tested-by: James Chapman <jchapman@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-28l2tp: fix l2tp_eth_dev_xmit()'s return typeLuc Van Oostenryck
The method ndo_start_xmit() is defined as returning an 'netdev_tx_t', which is a typedef for an enum type, but the implementation in this driver returns an 'int'. Fix this by returning 'netdev_tx_t' in this driver too. Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-14treewide: replace '---help---' in Kconfig files with 'help'Masahiro Yamada
Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over '---help---'"), the number of '---help---' has been gradually decreasing, but there are still more than 2400 instances. This commit finishes the conversion. While I touched the lines, I also fixed the indentation. There are a variety of indentation styles found. a) 4 spaces + '---help---' b) 7 spaces + '---help---' c) 8 spaces + '---help---' d) 1 space + 1 tab + '---help---' e) 1 tab + '---help---' (correct indentation) f) 1 tab + 1 space + '---help---' g) 1 tab + 2 spaces + '---help---' In order to convert all of them to 1 tab + 'help', I ran the following commend: $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/' Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
xdp_umem.c had overlapping changes between the 64-bit math fix for the calculation of npgs and the removal of the zerocopy memory type which got rid of the chunk_size_nohdr member. The mlx5 Kconfig conflict is a case where we just take the net-next copy of the Kconfig entry dependency as it takes on the ESWITCH dependency by one level of indirection which is what the 'net' conflicting change is trying to ensure. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-30l2tp: add sk_family checks to l2tp_validate_socketEric Dumazet
syzbot was able to trigger a crash after using an ISDN socket and fool l2tp. Fix this by making sure the UDP socket is of the proper family. BUG: KASAN: slab-out-of-bounds in setup_udp_tunnel_sock+0x465/0x540 net/ipv4/udp_tunnel.c:78 Write of size 1 at addr ffff88808ed0c590 by task syz-executor.5/3018 CPU: 0 PID: 3018 Comm: syz-executor.5 Not tainted 5.7.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:382 __kasan_report.cold+0x20/0x38 mm/kasan/report.c:511 kasan_report+0x33/0x50 mm/kasan/common.c:625 setup_udp_tunnel_sock+0x465/0x540 net/ipv4/udp_tunnel.c:78 l2tp_tunnel_register+0xb15/0xdd0 net/l2tp/l2tp_core.c:1523 l2tp_nl_cmd_tunnel_create+0x4b2/0xa60 net/l2tp/l2tp_netlink.c:249 genl_family_rcv_msg_doit net/netlink/genetlink.c:673 [inline] genl_family_rcv_msg net/netlink/genetlink.c:718 [inline] genl_rcv_msg+0x627/0xdf0 net/netlink/genetlink.c:735 netlink_rcv_skb+0x15a/0x410 net/netlink/af_netlink.c:2469 genl_rcv+0x24/0x40 net/netlink/genetlink.c:746 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x6e6/0x810 net/socket.c:2352 ___sys_sendmsg+0x100/0x170 net/socket.c:2406 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2439 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45ca29 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007effe76edc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000004fe1c0 RCX: 000000000045ca29 RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000005 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000094e R14: 00000000004d5d00 R15: 00007effe76ee6d4 Allocated by task 3018: save_stack+0x1b/0x40 mm/kasan/common.c:49 set_track mm/kasan/common.c:57 [inline] __kasan_kmalloc mm/kasan/common.c:495 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:468 __do_kmalloc mm/slab.c:3656 [inline] __kmalloc+0x161/0x7a0 mm/slab.c:3665 kmalloc include/linux/slab.h:560 [inline] sk_prot_alloc+0x223/0x2f0 net/core/sock.c:1612 sk_alloc+0x36/0x1100 net/core/sock.c:1666 data_sock_create drivers/isdn/mISDN/socket.c:600 [inline] mISDN_sock_create+0x272/0x400 drivers/isdn/mISDN/socket.c:796 __sock_create+0x3cb/0x730 net/socket.c:1428 sock_create net/socket.c:1479 [inline] __sys_socket+0xef/0x200 net/socket.c:1521 __do_sys_socket net/socket.c:1530 [inline] __se_sys_socket net/socket.c:1528 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1528 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Freed by task 2484: save_stack+0x1b/0x40 mm/kasan/common.c:49 set_track mm/kasan/common.c:57 [inline] kasan_set_free_info mm/kasan/common.c:317 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:456 __cache_free mm/slab.c:3426 [inline] kfree+0x109/0x2b0 mm/slab.c:3757 kvfree+0x42/0x50 mm/util.c:603 __free_fdtable+0x2d/0x70 fs/file.c:31 put_files_struct fs/file.c:420 [inline] put_files_struct+0x248/0x2e0 fs/file.c:413 exit_files+0x7e/0xa0 fs/file.c:445 do_exit+0xb04/0x2dd0 kernel/exit.c:791 do_group_exit+0x125/0x340 kernel/exit.c:894 get_signal+0x47b/0x24e0 kernel/signal.c:2739 do_signal+0x81/0x2240 arch/x86/kernel/signal.c:784 exit_to_usermode_loop+0x26c/0x360 arch/x86/entry/common.c:161 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305 entry_SYSCALL_64_after_hwframe+0x49/0xb3 The buggy address belongs to the object at ffff88808ed0c000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1424 bytes inside of 2048-byte region [ffff88808ed0c000, ffff88808ed0c800) The buggy address belongs to the page: page:ffffea00023b4300 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea0002838208 ffffea00015ba288 ffff8880aa000e00 raw: 0000000000000000 ffff88808ed0c000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808ed0c480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88808ed0c500: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88808ed0c580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88808ed0c600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808ed0c680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc Fixes: 6b9f34239b00 ("l2tp: fix races in tunnel creation") Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: James Chapman <jchapman@katalix.com> Cc: Guillaume Nault <gnault@redhat.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-30l2tp: do not use inet_hash()/inet_unhash()Eric Dumazet
syzbot recently found a way to crash the kernel [1] Issue here is that inet_hash() & inet_unhash() are currently only meant to be used by TCP & DCCP, since only these protocols provide the needed hashinfo pointer. L2TP uses a single list (instead of a hash table) This old bug became an issue after commit 610236587600 ("bpf: Add new cgroup attach type to enable sock modifications") since after this commit, sk_common_release() can be called while the L2TP socket is still considered 'hashed'. general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 0 PID: 7063 Comm: syz-executor654 Not tainted 5.7.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:inet_unhash+0x11f/0x770 net/ipv4/inet_hashtables.c:600 Code: 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e dd 04 00 00 48 8d 7d 08 44 8b 73 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 55 05 00 00 48 8d 7d 14 4c 8b 6d 08 48 b8 00 00 RSP: 0018:ffffc90001777d30 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffff88809a6df940 RCX: ffffffff8697c242 RDX: 0000000000000001 RSI: ffffffff8697c251 RDI: 0000000000000008 RBP: 0000000000000000 R08: ffff88809f3ae1c0 R09: fffffbfff1514cc1 R10: ffffffff8a8a6607 R11: fffffbfff1514cc0 R12: ffff88809a6df9b0 R13: 0000000000000007 R14: 0000000000000000 R15: ffffffff873a4d00 FS: 0000000001d2b880(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000006cd090 CR3: 000000009403a000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sk_common_release+0xba/0x370 net/core/sock.c:3210 inet_create net/ipv4/af_inet.c:390 [inline] inet_create+0x966/0xe00 net/ipv4/af_inet.c:248 __sock_create+0x3cb/0x730 net/socket.c:1428 sock_create net/socket.c:1479 [inline] __sys_socket+0xef/0x200 net/socket.c:1521 __do_sys_socket net/socket.c:1530 [inline] __se_sys_socket net/socket.c:1528 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1528 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x441e29 Code: e8 fc b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 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 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffdce184148 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441e29 RDX: 0000000000000073 RSI: 0000000000000002 RDI: 0000000000000002 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000402c30 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: ---[ end trace 23b6578228ce553e ]--- RIP: 0010:inet_unhash+0x11f/0x770 net/ipv4/inet_hashtables.c:600 Code: 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e dd 04 00 00 48 8d 7d 08 44 8b 73 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 55 05 00 00 48 8d 7d 14 4c 8b 6d 08 48 b8 00 00 RSP: 0018:ffffc90001777d30 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffff88809a6df940 RCX: ffffffff8697c242 RDX: 0000000000000001 RSI: ffffffff8697c251 RDI: 0000000000000008 RBP: 0000000000000000 R08: ffff88809f3ae1c0 R09: fffffbfff1514cc1 R10: ffffffff8a8a6607 R11: fffffbfff1514cc0 R12: ffff88809a6df9b0 R13: 0000000000000007 R14: 0000000000000000 R15: ffffffff873a4d00 FS: 0000000001d2b880(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000006cd090 CR3: 000000009403a000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Fixes: 0d76751fad77 ("l2tp: Add L2TPv3 IP encapsulation (no UDP) support") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: James Chapman <jchapman@katalix.com> Cc: Andrii Nakryiko <andriin@fb.com> Reported-by: syzbot+3610d489778b57cc8031@syzkaller.appspotmail.com
2020-05-18ipv6: move SIOCADDRT and SIOCDELRT handling into ->compat_ioctlChristoph Hellwig
To prepare removing the global routing_ioctl hack start lifting the code into a newly added ipv6 ->compat_ioctl handler. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-04net: partially revert dynamic lockdep key changesCong Wang
This patch reverts the folowing commits: commit 064ff66e2bef84f1153087612032b5b9eab005bd "bonding: add missing netdev_update_lockdep_key()" commit 53d374979ef147ab51f5d632dfe20b14aebeccd0 "net: avoid updating qdisc_xmit_lock_key in netdev_update_lockdep_key()" commit 1f26c0d3d24125992ab0026b0dab16c08df947c7 "net: fix kernel-doc warning in <linux/netdevice.h>" commit ab92d68fc22f9afab480153bd82a20f6e2533769 "net: core: add generic lockdep keys" but keeps the addr_list_lock_key because we still lock addr_list_lock nestedly on stack devices, unlikely xmit_lock this is safe because we don't take addr_list_lock on any fast path. Reported-and-tested-by: syzbot+aaa6fa4949cc5d9b7b25@syzkaller.appspotmail.com Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-08l2tp: Allow management of tunnels and session in user namespaceMichael Weiß
Creation and management of L2TPv3 tunnels and session through netlink requires CAP_NET_ADMIN. However, a process with CAP_NET_ADMIN in a non-initial user namespace gets an EPERM due to the use of the genetlink GENL_ADMIN_PERM flag. Thus, management of L2TP VPNs inside an unprivileged container won't work. We replaced the GENL_ADMIN_PERM by the GENL_UNS_ADMIN_PERM flag similar to other network modules which also had this problem, e.g., openvswitch (commit 4a92602aa1cd "openvswitch: allow management from inside user namespaces") and nl80211 (commit 5617c6cd6f844 "nl80211: Allow privileged operations from user namespaces"). I tested this in the container runtime trustm3 (trustm3.github.io) and was able to create l2tp tunnels and sessions in unpriviliged (user namespaced) containers using a private network namespace. For other runtimes such as docker or lxc this should work, too. Signed-off-by: Michael Weiß <michael.weiss@aisec.fraunhofer.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-28l2tp: Replace zero-length array with flexible-array memberGustavo A. R. Silva
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] Lastly, fix the following checkpatch warning: CHECK: Prefer kernel type 'u8' over 'uint8_t' #50: FILE: net/l2tp/l2tp_core.h:119: + uint8_t priv[]; /* private data */ This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-04l2tp: Allow duplicate session creation with UDPRidge Kennedy
In the past it was possible to create multiple L2TPv3 sessions with the same session id as long as the sessions belonged to different tunnels. The resulting sessions had issues when used with IP encapsulated tunnels, but worked fine with UDP encapsulated ones. Some applications began to rely on this behaviour to avoid having to negotiate unique session ids. Some time ago a change was made to require session ids to be unique across all tunnels, breaking the applications making use of this "feature". This change relaxes the duplicate session id check to allow duplicates if both of the colliding sessions belong to UDP encapsulated tunnels. Fixes: dbdbc73b4478 ("l2tp: fix duplicate session creation") Signed-off-by: Ridge Kennedy <ridge.kennedy@alliedtelesis.co.nz> Acked-by: James Chapman <jchapman@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-03l2tp: Remove redundant BUG_ON() check in l2tp_pernetXu Wang
Passing NULL to l2tp_pernet causes a crash via BUG_ON. Dereferencing net in net_generic() also has the same effect. This patch removes the redundant BUG_ON check on the same parameter. Signed-off-by: Xu Wang <vulab@iscas.ac.cn> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-04net: ipv6: add net argument to ip6_dst_lookup_flowSabrina Dubroca
This will be used in the conversion of ipv6_stub to ip6_dst_lookup_flow, as some modules currently pass a net argument without a socket to ip6_dst_lookup. This is equivalent to commit 343d60aada5a ("ipv6: change ipv6_stub_impl.ipv6_dst_lookup to take net argument"). Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-24net: core: add generic lockdep keysTaehee Yoo
Some interface types could be nested. (VLAN, BONDING, TEAM, MACSEC, MACVLAN, IPVLAN, VIRT_WIFI, VXLAN, etc..) These interface types should set lockdep class because, without lockdep class key, lockdep always warn about unexisting circular locking. In the current code, these interfaces have their own lockdep class keys and these manage itself. So that there are so many duplicate code around the /driver/net and /net/. This patch adds new generic lockdep keys and some helper functions for it. This patch does below changes. a) Add lockdep class keys in struct net_device - qdisc_running, xmit, addr_list, qdisc_busylock - these keys are used as dynamic lockdep key. b) When net_device is being allocated, lockdep keys are registered. - alloc_netdev_mqs() c) When net_device is being free'd llockdep keys are unregistered. - free_netdev() d) Add generic lockdep key helper function - netdev_register_lockdep_key() - netdev_unregister_lockdep_key() - netdev_update_lockdep_key() e) Remove unnecessary generic lockdep macro and functions f) Remove unnecessary lockdep code of each interfaces. After this patch, each interface modules don't need to maintain their lockdep keys. Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>