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2022-03-03mm: don't include <linux/memremap.h> in <linux/mm.h>Christoph Hellwig
Move the check for the actual pgmap types that need the free at refcount one behavior into the out of line helper, and thus avoid the need to pull memremap.h into mm.h. Link: https://lkml.kernel.org/r/20220210072828.2930359-7-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Felix Kuehling <Felix.Kuehling@amd.com> Tested-by: "Sierra Guiza, Alejandro (Alex)" <alex.sierra@amd.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Chaitanya Kulkarni <kch@nvidia.com> Cc: Karol Herbst <kherbst@redhat.com> Cc: Lyude Paul <lyude@redhat.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-03-03ext4: don't BUG if someone dirty pages without asking ext4 firstTheodore Ts'o
[un]pin_user_pages_remote is dirtying pages without properly warning the file system in advance. A related race was noted by Jan Kara in 2018[1]; however, more recently instead of it being a very hard-to-hit race, it could be reliably triggered by process_vm_writev(2) which was discovered by Syzbot[2]. This is technically a bug in mm/gup.c, but arguably ext4 is fragile in that if some other kernel subsystem dirty pages without properly notifying the file system using page_mkwrite(), ext4 will BUG, while other file systems will not BUG (although data will still be lost). So instead of crashing with a BUG, issue a warning (since there may be potential data loss) and just mark the page as clean to avoid unprivileged denial of service attacks until the problem can be properly fixed. More discussion and background can be found in the thread starting at [2]. [1] https://lore.kernel.org/linux-mm/20180103100430.GE4911@quack2.suse.cz [2] https://lore.kernel.org/r/Yg0m6IjcNmfaSokM@google.com Reported-by: syzbot+d59332e2db681cf18f0318a06e994ebbb529a8db@syzkaller.appspotmail.com Reported-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Link: https://lore.kernel.org/r/YiDS9wVfq4mM2jGK@mit.edu
2022-03-03gfs2: Remove return value for gfs2_indirect_initBob Peterson
The return value from function gfs2_indirect_init is never used, so remove it. Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-03-03ext4: remove redundant assignment to variable split_flag1Colin Ian King
Variable split_flag1 is being assigned a value that is never read, it is being re-assigned a new value in the following code block. The assignment is redundant and can be removed. Cleans up clang scan build warning: fs/ext4/extents.c:3371:2: warning: Value stored to 'split_flag1' is never read [deadcode.DeadStores] Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Link: https://lore.kernel.org/r/20220301121644.997833-1-colin.i.king@gmail.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-03-02ext4: fix underflow in ext4_max_bitmap_size()Zhang Yi
when ext4 filesystem is created with 64k block size, ^extent and ^huge_file features. the upper_limit would underflow during the computations in ext4_max_bitmap_size(). The problem is the size of block index tree for such large block size is more than i_blocks can carry. So fix the computation to count with this possibility. After this fix, the 'res' cannot overflow loff_t on the extreme case of filesystem with huge_files and 64K block size, so this patch also revert commit 75ca6ad408f4 ("ext4: fix loff_t overflow in ext4_max_bitmap_size()"). Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220301111704.2153829-1-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-03-02ext4: fix ext4_mb_clear_bb() kernel-doc commentYang Li
Remove the excess description of @bh in ext4_mb_clear_bb() kernel-doc comment to remove warnings found by running scripts/kernel-doc, which is caused by using 'make W=1'. fs/ext4/mballoc.c:5895: warning: Excess function parameter 'bh' description in 'ext4_mb_clear_bb' Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Link: https://lore.kernel.org/r/20220301092136.34764-1-yang.lee@linux.alibaba.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-03-02ext4: fix fs corruption when tring to remove a non-empty directory with IO errorYe Bin
We inject IO error when rmdir non empty direcory, then got issue as follows: step1: mkfs.ext4 -F /dev/sda step2: mount /dev/sda test step3: cd test step4: mkdir -p 1/2 step5: rmdir 1 [ 110.920551] ext4_empty_dir: inject fault [ 110.921926] EXT4-fs warning (device sda): ext4_rmdir:3113: inode #12: comm rmdir: empty directory '1' has too many links (3) step6: cd .. step7: umount test step8: fsck.ext4 -f /dev/sda e2fsck 1.42.9 (28-Dec-2013) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Entry '..' in .../??? (13) has deleted/unused inode 12. Clear<y>? yes Pass 3: Checking directory connectivity Unconnected directory inode 13 (...) Connect to /lost+found<y>? yes Pass 4: Checking reference counts Inode 13 ref count is 3, should be 2. Fix<y>? yes Pass 5: Checking group summary information /dev/sda: ***** FILE SYSTEM WAS MODIFIED ***** /dev/sda: 12/131072 files (0.0% non-contiguous), 26157/524288 blocks ext4_rmdir if (!ext4_empty_dir(inode)) goto end_rmdir; ext4_empty_dir bh = ext4_read_dirblock(inode, 0, DIRENT_HTREE); if (IS_ERR(bh)) return true; Now if read directory block failed, 'ext4_empty_dir' will return true, assume directory is empty. Obviously, it will lead to above issue. To solve this issue, if read directory block failed 'ext4_empty_dir' just return false. To avoid making things worse when file system is already corrupted, 'ext4_empty_dir' also return false. Signed-off-by: Ye Bin <yebin10@huawei.com> Cc: stable@kernel.org Link: https://lore.kernel.org/r/20220228024815.3952506-1-yebin10@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-03-02ext4: use time_is_before_jiffies() instead of open coding itWang Qing
Use the helper function time_is_{before,after}_jiffies() to improve code readability. Signed-off-by: Wang Qing <wangqing@vivo.com> Link: https://lore.kernel.org/r/1646018120-61462-1-git-send-email-wangqing@vivo.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-03-02ext4: improve fast_commit performance and scalabilityRitesh Harjani
Currently ext4_fc_commit_dentry_updates() is of quadratic time complexity, which is causing performance bottlenecks with high threads/file/dir count with fs_mark. This patch makes commit dentry updates (and hence ext4_fc_commit()) path to linear time complexity. Hence improves the performance of workloads which does fsync on multiple threads/open files one-by-one. Absolute numbers in avg file creates per sec (from fs_mark in 1K order) ======================================================================= no. Order without-patch(K) with-patch(K) Diff(%) 1 1 16.90 17.51 +3.60 2 2,2 32.08 31.80 -0.87 3 3,3 53.97 55.01 +1.92 4 4,4 78.94 76.90 -2.58 5 5,5 95.82 95.37 -0.46 6 6,6 87.92 103.38 +17.58 7 6,10 0.73 126.13 +17178.08 8 6,14 2.33 143.19 +6045.49 workload type ============== For e.g. 7th row order of 6,10 (2^6 == 64 && 2^10 == 1024) echo /run/riteshh/mnt/{1..64} |sed -E 's/[[:space:]]+/ -d /g' \ | xargs -I {} bash -c "sudo fs_mark -L 100 -D 1024 -n 1024 -s0 -S5 -d {}" Perf profile (w/o patches) ============================= 87.15% [kernel] [k] ext4_fc_commit --> Heavy contention/bottleneck 1.98% [kernel] [k] perf_event_interrupt 0.96% [kernel] [k] power_pmu_enable 0.91% [kernel] [k] update_sd_lb_stats.constprop.0 0.67% [kernel] [k] ktime_get Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com> Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com> Link: https://lore.kernel.org/r/930f35d4fd5f83e2673c868781d9ebf15e91bf4e.1645426817.git.riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-03-02Merge tag 'erofs-for-5.17-rc7-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs Pull erofs fix from Gao Xiang: "A one-line patch to fix the new ztailpacking feature on > 4GiB filesystems because z_idataoff can get trimmed improperly. ztailpacking is still a brand new EXPERIMENTAL feature, but it'd be better to fix the issue as soon as possible to avoid unnecessary backporting. Summary: - Fix ztailpacking z_idataoff getting trimmed on > 4GiB filesystems" * tag 'erofs-for-5.17-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: erofs: fix ztailpacking on > 4GiB filesystems
2022-03-02reiserfs: Deprecate reiserfsJan Kara
Reiserfs is relatively old filesystem and its development has ceased quite some years ago. Linux distributions moved away from it towards other filesystems such as btrfs, xfs, or ext4. To reduce maintenance burden on cross filesystem changes (such as new mount API, iomap, folios ...) let's add a deprecation notice when the filesystem is mounted and schedule its removal to 2025. Link: https://lore.kernel.org/r/20220225125445.29942-1-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz>
2022-03-02btrfs: add missing run of delayed items after unlink during log replayFilipe Manana
During log replay, whenever we need to check if a name (dentry) exists in a directory we do searches on the subvolume tree for inode references or or directory entries (BTRFS_DIR_INDEX_KEY keys, and BTRFS_DIR_ITEM_KEY keys as well, before kernel 5.17). However when during log replay we unlink a name, through btrfs_unlink_inode(), we may not delete inode references and dir index keys from a subvolume tree and instead just add the deletions to the delayed inode's delayed items, which will only be run when we commit the transaction used for log replay. This means that after an unlink operation during log replay, if we attempt to search for the same name during log replay, we will not see that the name was already deleted, since the deletion is recorded only on the delayed items. We run delayed items after every unlink operation during log replay, except at unlink_old_inode_refs() and at add_inode_ref(). This was due to an overlook, as delayed items should be run after evert unlink, for the reasons stated above. So fix those two cases. Fixes: 0d836392cadd5 ("Btrfs: fix mount failure after fsync due to hard link recreation") Fixes: 1f250e929a9c9 ("Btrfs: fix log replay failure after unlink and link combination") CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-02btrfs: qgroup: fix deadlock between rescan worker and remove qgroupSidong Yang
The commit e804861bd4e6 ("btrfs: fix deadlock between quota disable and qgroup rescan worker") by Kawasaki resolves deadlock between quota disable and qgroup rescan worker. But also there is a deadlock case like it. It's about enabling or disabling quota and creating or removing qgroup. It can be reproduced in simple script below. for i in {1..100} do btrfs quota enable /mnt & btrfs qgroup create 1/0 /mnt & btrfs qgroup destroy 1/0 /mnt & btrfs quota disable /mnt & done Here's why the deadlock happens: 1) The quota rescan task is running. 2) Task A calls btrfs_quota_disable(), locks the qgroup_ioctl_lock mutex, and then calls btrfs_qgroup_wait_for_completion(), to wait for the quota rescan task to complete. 3) Task B calls btrfs_remove_qgroup() and it blocks when trying to lock the qgroup_ioctl_lock mutex, because it's being held by task A. At that point task B is holding a transaction handle for the current transaction. 4) The quota rescan task calls btrfs_commit_transaction(). This results in it waiting for all other tasks to release their handles on the transaction, but task B is blocked on the qgroup_ioctl_lock mutex while holding a handle on the transaction, and that mutex is being held by task A, which is waiting for the quota rescan task to complete, resulting in a deadlock between these 3 tasks. To resolve this issue, the thread disabling quota should unlock qgroup_ioctl_lock before waiting rescan completion. Move btrfs_qgroup_wait_for_completion() after unlock of qgroup_ioctl_lock. Fixes: e804861bd4e6 ("btrfs: fix deadlock between quota disable and qgroup rescan worker") CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Signed-off-by: Sidong Yang <realwakka@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-02btrfs: fix relocation crash due to premature return from ↵Omar Sandoval
btrfs_commit_transaction() We are seeing crashes similar to the following trace: [38.969182] WARNING: CPU: 20 PID: 2105 at fs/btrfs/relocation.c:4070 btrfs_relocate_block_group+0x2dc/0x340 [btrfs] [38.973556] CPU: 20 PID: 2105 Comm: btrfs Not tainted 5.17.0-rc4 #54 [38.974580] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [38.976539] RIP: 0010:btrfs_relocate_block_group+0x2dc/0x340 [btrfs] [38.980336] RSP: 0000:ffffb0dd42e03c20 EFLAGS: 00010206 [38.981218] RAX: ffff96cfc4ede800 RBX: ffff96cfc3ce0000 RCX: 000000000002ca14 [38.982560] RDX: 0000000000000000 RSI: 4cfd109a0bcb5d7f RDI: ffff96cfc3ce0360 [38.983619] RBP: ffff96cfc309c000 R08: 0000000000000000 R09: 0000000000000000 [38.984678] R10: ffff96cec0000001 R11: ffffe84c80000000 R12: ffff96cfc4ede800 [38.985735] R13: 0000000000000000 R14: 0000000000000000 R15: ffff96cfc3ce0360 [38.987146] FS: 00007f11c15218c0(0000) GS:ffff96d6dfb00000(0000) knlGS:0000000000000000 [38.988662] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [38.989398] CR2: 00007ffc922c8e60 CR3: 00000001147a6001 CR4: 0000000000370ee0 [38.990279] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [38.991219] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [38.992528] Call Trace: [38.992854] <TASK> [38.993148] btrfs_relocate_chunk+0x27/0xe0 [btrfs] [38.993941] btrfs_balance+0x78e/0xea0 [btrfs] [38.994801] ? vsnprintf+0x33c/0x520 [38.995368] ? __kmalloc_track_caller+0x351/0x440 [38.996198] btrfs_ioctl_balance+0x2b9/0x3a0 [btrfs] [38.997084] btrfs_ioctl+0x11b0/0x2da0 [btrfs] [38.997867] ? mod_objcg_state+0xee/0x340 [38.998552] ? seq_release+0x24/0x30 [38.999184] ? proc_nr_files+0x30/0x30 [38.999654] ? call_rcu+0xc8/0x2f0 [39.000228] ? __x64_sys_ioctl+0x84/0xc0 [39.000872] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [39.001973] __x64_sys_ioctl+0x84/0xc0 [39.002566] do_syscall_64+0x3a/0x80 [39.003011] entry_SYSCALL_64_after_hwframe+0x44/0xae [39.003735] RIP: 0033:0x7f11c166959b [39.007324] RSP: 002b:00007fff2543e998 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [39.008521] RAX: ffffffffffffffda RBX: 00007f11c1521698 RCX: 00007f11c166959b [39.009833] RDX: 00007fff2543ea40 RSI: 00000000c4009420 RDI: 0000000000000003 [39.011270] RBP: 0000000000000003 R08: 0000000000000013 R09: 00007f11c16f94e0 [39.012581] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff25440df3 [39.014046] R13: 0000000000000000 R14: 00007fff2543ea40 R15: 0000000000000001 [39.015040] </TASK> [39.015418] ---[ end trace 0000000000000000 ]--- [43.131559] ------------[ cut here ]------------ [43.132234] kernel BUG at fs/btrfs/extent-tree.c:2717! [43.133031] invalid opcode: 0000 [#1] PREEMPT SMP PTI [43.133702] CPU: 1 PID: 1839 Comm: btrfs Tainted: G W 5.17.0-rc4 #54 [43.134863] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 [43.136426] RIP: 0010:unpin_extent_range+0x37a/0x4f0 [btrfs] [43.139913] RSP: 0000:ffffb0dd4216bc70 EFLAGS: 00010246 [43.140629] RAX: 0000000000000000 RBX: ffff96cfc34490f8 RCX: 0000000000000001 [43.141604] RDX: 0000000080000001 RSI: 0000000051d00000 RDI: 00000000ffffffff [43.142645] RBP: 0000000000000000 R08: 0000000000000000 R09: ffff96cfd07dca50 [43.143669] R10: ffff96cfc46e8a00 R11: fffffffffffec000 R12: 0000000041d00000 [43.144657] R13: ffff96cfc3ce0000 R14: ffffb0dd4216bd08 R15: 0000000000000000 [43.145686] FS: 00007f7657dd68c0(0000) GS:ffff96d6df640000(0000) knlGS:0000000000000000 [43.146808] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [43.147584] CR2: 00007f7fe81bf5b0 CR3: 00000001093ee004 CR4: 0000000000370ee0 [43.148589] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [43.149581] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [43.150559] Call Trace: [43.150904] <TASK> [43.151253] btrfs_finish_extent_commit+0x88/0x290 [btrfs] [43.152127] btrfs_commit_transaction+0x74f/0xaa0 [btrfs] [43.152932] ? btrfs_attach_transaction_barrier+0x1e/0x50 [btrfs] [43.153786] btrfs_ioctl+0x1edc/0x2da0 [btrfs] [43.154475] ? __check_object_size+0x150/0x170 [43.155170] ? preempt_count_add+0x49/0xa0 [43.155753] ? __x64_sys_ioctl+0x84/0xc0 [43.156437] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [43.157456] __x64_sys_ioctl+0x84/0xc0 [43.157980] do_syscall_64+0x3a/0x80 [43.158543] entry_SYSCALL_64_after_hwframe+0x44/0xae [43.159231] RIP: 0033:0x7f7657f1e59b [43.161819] RSP: 002b:00007ffda5cd1658 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [43.162702] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f7657f1e59b [43.163526] RDX: 0000000000000000 RSI: 0000000000009408 RDI: 0000000000000003 [43.164358] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 [43.165208] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [43.166029] R13: 00005621b91c3232 R14: 00005621b91ba580 R15: 00007ffda5cd1800 [43.166863] </TASK> [43.167125] Modules linked in: btrfs blake2b_generic xor pata_acpi ata_piix libata raid6_pq scsi_mod libcrc32c virtio_net virtio_rng net_failover rng_core failover scsi_common [43.169552] ---[ end trace 0000000000000000 ]--- [43.171226] RIP: 0010:unpin_extent_range+0x37a/0x4f0 [btrfs] [43.174767] RSP: 0000:ffffb0dd4216bc70 EFLAGS: 00010246 [43.175600] RAX: 0000000000000000 RBX: ffff96cfc34490f8 RCX: 0000000000000001 [43.176468] RDX: 0000000080000001 RSI: 0000000051d00000 RDI: 00000000ffffffff [43.177357] RBP: 0000000000000000 R08: 0000000000000000 R09: ffff96cfd07dca50 [43.178271] R10: ffff96cfc46e8a00 R11: fffffffffffec000 R12: 0000000041d00000 [43.179178] R13: ffff96cfc3ce0000 R14: ffffb0dd4216bd08 R15: 0000000000000000 [43.180071] FS: 00007f7657dd68c0(0000) GS:ffff96d6df800000(0000) knlGS:0000000000000000 [43.181073] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [43.181808] CR2: 00007fe09905f010 CR3: 00000001093ee004 CR4: 0000000000370ee0 [43.182706] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [43.183591] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 We first hit the WARN_ON(rc->block_group->pinned > 0) in btrfs_relocate_block_group() and then the BUG_ON(!cache) in unpin_extent_range(). This tells us that we are exiting relocation and removing the block group with bytes still pinned for that block group. This is supposed to be impossible: the last thing relocate_block_group() does is commit the transaction to get rid of pinned extents. Commit d0c2f4fa555e ("btrfs: make concurrent fsyncs wait less when waiting for a transaction commit") introduced an optimization so that commits from fsync don't have to wait for the previous commit to unpin extents. This was only intended to affect fsync, but it inadvertently made it possible for any commit to skip waiting for the previous commit to unpin. This is because if a call to btrfs_commit_transaction() finds that another thread is already committing the transaction, it waits for the other thread to complete the commit and then returns. If that other thread was in fsync, then it completes the commit without completing the previous commit. This makes the following sequence of events possible: Thread 1____________________|Thread 2 (fsync)_____________________|Thread 3 (balance)___________________ btrfs_commit_transaction(N) | | btrfs_run_delayed_refs | | pin extents | | ... | | state = UNBLOCKED |btrfs_sync_file | | btrfs_start_transaction(N + 1) |relocate_block_group | | btrfs_join_transaction(N + 1) | btrfs_commit_transaction(N + 1) | ... | trans->state = COMMIT_START | | | btrfs_commit_transaction(N + 1) | | wait_for_commit(N + 1, COMPLETED) | wait_for_commit(N, SUPER_COMMITTED)| state = SUPER_COMMITTED | ... | btrfs_finish_extent_commit| | unpin_extent_range() | trans->state = COMPLETED | | | return | | ... | |Thread 1 isn't done, so pinned > 0 | |and we WARN | | | |btrfs_remove_block_group unpin_extent_range() | | Thread 3 removed the | | block group, so we BUG| | There are other sequences involving SUPER_COMMITTED transactions that can cause a similar outcome. We could fix this by making relocation explicitly wait for unpinning, but there may be other cases that need it. Josef mentioned ENOSPC flushing and the free space cache inode as other potential victims. Rather than playing whack-a-mole, this fix is conservative and makes all commits not in fsync wait for all previous transactions, which is what the optimization intended. Fixes: d0c2f4fa555e ("btrfs: make concurrent fsyncs wait less when waiting for a transaction commit") CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-02btrfs: do not start relocation until in progress drops are doneJosef Bacik
We hit a bug with a recovering relocation on mount for one of our file systems in production. I reproduced this locally by injecting errors into snapshot delete with balance running at the same time. This presented as an error while looking up an extent item WARNING: CPU: 5 PID: 1501 at fs/btrfs/extent-tree.c:866 lookup_inline_extent_backref+0x647/0x680 CPU: 5 PID: 1501 Comm: btrfs-balance Not tainted 5.16.0-rc8+ #8 RIP: 0010:lookup_inline_extent_backref+0x647/0x680 RSP: 0018:ffffae0a023ab960 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 000000000000000c RDI: 0000000000000000 RBP: ffff943fd2a39b60 R08: 0000000000000000 R09: 0000000000000001 R10: 0001434088152de0 R11: 0000000000000000 R12: 0000000001d05000 R13: ffff943fd2a39b60 R14: ffff943fdb96f2a0 R15: ffff9442fc923000 FS: 0000000000000000(0000) GS:ffff944e9eb40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1157b1fca8 CR3: 000000010f092000 CR4: 0000000000350ee0 Call Trace: <TASK> insert_inline_extent_backref+0x46/0xd0 __btrfs_inc_extent_ref.isra.0+0x5f/0x200 ? btrfs_merge_delayed_refs+0x164/0x190 __btrfs_run_delayed_refs+0x561/0xfa0 ? btrfs_search_slot+0x7b4/0xb30 ? btrfs_update_root+0x1a9/0x2c0 btrfs_run_delayed_refs+0x73/0x1f0 ? btrfs_update_root+0x1a9/0x2c0 btrfs_commit_transaction+0x50/0xa50 ? btrfs_update_reloc_root+0x122/0x220 prepare_to_merge+0x29f/0x320 relocate_block_group+0x2b8/0x550 btrfs_relocate_block_group+0x1a6/0x350 btrfs_relocate_chunk+0x27/0xe0 btrfs_balance+0x777/0xe60 balance_kthread+0x35/0x50 ? btrfs_balance+0xe60/0xe60 kthread+0x16b/0x190 ? set_kthread_struct+0x40/0x40 ret_from_fork+0x22/0x30 </TASK> Normally snapshot deletion and relocation are excluded from running at the same time by the fs_info->cleaner_mutex. However if we had a pending balance waiting to get the ->cleaner_mutex, and a snapshot deletion was running, and then the box crashed, we would come up in a state where we have a half deleted snapshot. Again, in the normal case the snapshot deletion needs to complete before relocation can start, but in this case relocation could very well start before the snapshot deletion completes, as we simply add the root to the dead roots list and wait for the next time the cleaner runs to clean up the snapshot. Fix this by setting a bit on the fs_info if we have any DEAD_ROOT's that had a pending drop_progress key. If they do then we know we were in the middle of the drop operation and set a flag on the fs_info. Then balance can wait until this flag is cleared to start up again. If there are DEAD_ROOT's that don't have a drop_progress set then we're safe to start balance right away as we'll be properly protected by the cleaner_mutex. CC: stable@vger.kernel.org # 5.10+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-02btrfs: tree-checker: use u64 for item data end to avoid overflowSu Yue
User reported there is an array-index-out-of-bounds access while mounting the crafted image: [350.411942 ] loop0: detected capacity change from 0 to 262144 [350.427058 ] BTRFS: device fsid a62e00e8-e94e-4200-8217-12444de93c2e devid 1 transid 8 /dev/loop0 scanned by systemd-udevd (1044) [350.428564 ] BTRFS info (device loop0): disk space caching is enabled [350.428568 ] BTRFS info (device loop0): has skinny extents [350.429589 ] [350.429619 ] UBSAN: array-index-out-of-bounds in fs/btrfs/struct-funcs.c:161:1 [350.429636 ] index 1048096 is out of range for type 'page *[16]' [350.429650 ] CPU: 0 PID: 9 Comm: kworker/u8:1 Not tainted 5.16.0-rc4 [350.429652 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014 [350.429653 ] Workqueue: btrfs-endio-meta btrfs_work_helper [btrfs] [350.429772 ] Call Trace: [350.429774 ] <TASK> [350.429776 ] dump_stack_lvl+0x47/0x5c [350.429780 ] ubsan_epilogue+0x5/0x50 [350.429786 ] __ubsan_handle_out_of_bounds+0x66/0x70 [350.429791 ] btrfs_get_16+0xfd/0x120 [btrfs] [350.429832 ] check_leaf+0x754/0x1a40 [btrfs] [350.429874 ] ? filemap_read+0x34a/0x390 [350.429878 ] ? load_balance+0x175/0xfc0 [350.429881 ] validate_extent_buffer+0x244/0x310 [btrfs] [350.429911 ] btrfs_validate_metadata_buffer+0xf8/0x100 [btrfs] [350.429935 ] end_bio_extent_readpage+0x3af/0x850 [btrfs] [350.429969 ] ? newidle_balance+0x259/0x480 [350.429972 ] end_workqueue_fn+0x29/0x40 [btrfs] [350.429995 ] btrfs_work_helper+0x71/0x330 [btrfs] [350.430030 ] ? __schedule+0x2fb/0xa40 [350.430033 ] process_one_work+0x1f6/0x400 [350.430035 ] ? process_one_work+0x400/0x400 [350.430036 ] worker_thread+0x2d/0x3d0 [350.430037 ] ? process_one_work+0x400/0x400 [350.430038 ] kthread+0x165/0x190 [350.430041 ] ? set_kthread_struct+0x40/0x40 [350.430043 ] ret_from_fork+0x1f/0x30 [350.430047 ] </TASK> [350.430047 ] [350.430077 ] BTRFS warning (device loop0): bad eb member start: ptr 0xffe20f4e start 20975616 member offset 4293005178 size 2 btrfs check reports: corrupt leaf: root=3 block=20975616 physical=20975616 slot=1, unexpected item end, have 4294971193 expect 3897 The first slot item offset is 4293005033 and the size is 1966160. In check_leaf, we use btrfs_item_end() to check item boundary versus extent_buffer data size. However, return type of btrfs_item_end() is u32. (u32)(4293005033 + 1966160) == 3897, overflow happens and the result 3897 equals to leaf data size reasonably. Fix it by use u64 variable to store item data end in check_leaf() to avoid u32 overflow. This commit does solve the invalid memory access showed by the stack trace. However, its metadata profile is DUP and another copy of the leaf is fine. So the image can be mounted successfully. But when umount is called, the ASSERT btrfs_mark_buffer_dirty() will be triggered because the only node in extent tree has 0 item and invalid owner. It's solved by another commit "btrfs: check extent buffer owner against the owner rootid". Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215299 Reported-by: Wenqing Liu <wenqingliu0120@gmail.com> CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Su Yue <l@damenly.su> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-02btrfs: do not WARN_ON() if we have PageError setJosef Bacik
Whenever we do any extent buffer operations we call assert_eb_page_uptodate() to complain loudly if we're operating on an non-uptodate page. Our overnight tests caught this warning earlier this week WARNING: CPU: 1 PID: 553508 at fs/btrfs/extent_io.c:6849 assert_eb_page_uptodate+0x3f/0x50 CPU: 1 PID: 553508 Comm: kworker/u4:13 Tainted: G W 5.17.0-rc3+ #564 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Workqueue: btrfs-cache btrfs_work_helper RIP: 0010:assert_eb_page_uptodate+0x3f/0x50 RSP: 0018:ffffa961440a7c68 EFLAGS: 00010246 RAX: 0017ffffc0002112 RBX: ffffe6e74453f9c0 RCX: 0000000000001000 RDX: ffffe6e74467c887 RSI: ffffe6e74453f9c0 RDI: ffff8d4c5efc2fc0 RBP: 0000000000000d56 R08: ffff8d4d4a224000 R09: 0000000000000000 R10: 00015817fa9d1ef0 R11: 000000000000000c R12: 00000000000007b1 R13: ffff8d4c5efc2fc0 R14: 0000000001500000 R15: 0000000001cb1000 FS: 0000000000000000(0000) GS:ffff8d4dbbd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff31d3448d8 CR3: 0000000118be8004 CR4: 0000000000370ee0 Call Trace: extent_buffer_test_bit+0x3f/0x70 free_space_test_bit+0xa6/0xc0 load_free_space_tree+0x1f6/0x470 caching_thread+0x454/0x630 ? rcu_read_lock_sched_held+0x12/0x60 ? rcu_read_lock_sched_held+0x12/0x60 ? rcu_read_lock_sched_held+0x12/0x60 ? lock_release+0x1f0/0x2d0 btrfs_work_helper+0xf2/0x3e0 ? lock_release+0x1f0/0x2d0 ? finish_task_switch.isra.0+0xf9/0x3a0 process_one_work+0x26d/0x580 ? process_one_work+0x580/0x580 worker_thread+0x55/0x3b0 ? process_one_work+0x580/0x580 kthread+0xf0/0x120 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x1f/0x30 This was partially fixed by c2e39305299f01 ("btrfs: clear extent buffer uptodate when we fail to write it"), however all that fix did was keep us from finding extent buffers after a failed writeout. It didn't keep us from continuing to use a buffer that we already had found. In this case we're searching the commit root to cache the block group, so we can start committing the transaction and switch the commit root and then start writing. After the switch we can look up an extent buffer that hasn't been written yet and start processing that block group. Then we fail to write that block out and clear Uptodate on the page, and then we start spewing these errors. Normally we're protected by the tree lock to a certain degree here. If we read a block we have that block read locked, and we block the writer from locking the block before we submit it for the write. However this isn't necessarily fool proof because the read could happen before we do the submit_bio and after we locked and unlocked the extent buffer. Also in this particular case we have path->skip_locking set, so that won't save us here. We'll simply get a block that was valid when we read it, but became invalid while we were using it. What we really want is to catch the case where we've "read" a block but it's not marked Uptodate. On read we ClearPageError(), so if we're !Uptodate and !Error we know we didn't do the right thing for reading the page. Fix this by checking !Uptodate && !Error, this way we will not complain if our buffer gets invalidated while we're using it, and we'll maintain the spirit of the check which is to make sure we have a fully in-cache block while we're messing with it. CC: stable@vger.kernel.org # 5.4+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-02btrfs: fix lost prealloc extents beyond eof after full fsyncFilipe Manana
When doing a full fsync, if we have prealloc extents beyond (or at) eof, and the leaves that contain them were not modified in the current transaction, we end up not logging them. This results in losing those extents when we replay the log after a power failure, since the inode is truncated to the current value of the logged i_size. Just like for the fast fsync path, we need to always log all prealloc extents starting at or beyond i_size. The fast fsync case was fixed in commit 471d557afed155 ("Btrfs: fix loss of prealloc extents past i_size after fsync log replay") but it missed the full fsync path. The problem exists since the very early days, when the log tree was added by commit e02119d5a7b439 ("Btrfs: Add a write ahead tree log to optimize synchronous operations"). Example reproducer: $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt # Create our test file with many file extent items, so that they span # several leaves of metadata, even if the node/page size is 64K. Use # direct IO and not fsync/O_SYNC because it's both faster and it avoids # clearing the full sync flag from the inode - we want the fsync below # to trigger the slow full sync code path. $ xfs_io -f -d -c "pwrite -b 4K 0 16M" /mnt/foo # Now add two preallocated extents to our file without extending the # file's size. One right at i_size, and another further beyond, leaving # a gap between the two prealloc extents. $ xfs_io -c "falloc -k 16M 1M" /mnt/foo $ xfs_io -c "falloc -k 20M 1M" /mnt/foo # Make sure everything is durably persisted and the transaction is # committed. This makes all created extents to have a generation lower # than the generation of the transaction used by the next write and # fsync. sync # Now overwrite only the first extent, which will result in modifying # only the first leaf of metadata for our inode. Then fsync it. This # fsync will use the slow code path (inode full sync bit is set) because # it's the first fsync since the inode was created/loaded. $ xfs_io -c "pwrite 0 4K" -c "fsync" /mnt/foo # Extent list before power failure. $ xfs_io -c "fiemap -v" /mnt/foo /mnt/foo: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..7]: 2178048..2178055 8 0x0 1: [8..16383]: 26632..43007 16376 0x0 2: [16384..32767]: 2156544..2172927 16384 0x0 3: [32768..34815]: 2172928..2174975 2048 0x800 4: [34816..40959]: hole 6144 5: [40960..43007]: 2174976..2177023 2048 0x801 <power fail> # Mount fs again, trigger log replay. $ mount /dev/sdc /mnt # Extent list after power failure and log replay. $ xfs_io -c "fiemap -v" /mnt/foo /mnt/foo: EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS 0: [0..7]: 2178048..2178055 8 0x0 1: [8..16383]: 26632..43007 16376 0x0 2: [16384..32767]: 2156544..2172927 16384 0x1 # The prealloc extents at file offsets 16M and 20M are missing. So fix this by calling btrfs_log_prealloc_extents() when we are doing a full fsync, so that we always log all prealloc extents beyond eof. A test case for fstests will follow soon. CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-02btrfs: subpage: fix a wrong check on subpage->writersQu Wenruo
[BUG] When looping btrfs/074 with 64K page size and 4K sectorsize, there is a low chance (1/50~1/100) to crash with the following ASSERT() triggered in btrfs_subpage_start_writer(): ret = atomic_add_return(nbits, &subpage->writers); ASSERT(ret == nbits); <<< This one <<< [CAUSE] With more debugging output on the parameters of btrfs_subpage_start_writer(), it shows a very concerning error: ret=29 nbits=13 start=393216 len=53248 For @nbits it's correct, but @ret which is the returned value from atomic_add_return(), it's not only larger than nbits, but also larger than max sectors per page value (for 64K page size and 4K sector size, it's 16). This indicates that some call sites are not properly decreasing the value. And that's exactly the case, in btrfs_page_unlock_writer(), due to the fact that we can have page locked either by lock_page() or process_one_page(), we have to check if the subpage has any writer. If no writers, it's locked by lock_page() and we only need to unlock it. But unfortunately the check for the writers are completely opposite: if (atomic_read(&subpage->writers)) /* No writers, locked by plain lock_page() */ return unlock_page(page); We directly unlock the page if it has writers, which is the completely opposite what we want. Thankfully the affected call site is only limited to extent_write_locked_range(), so it's mostly affecting compressed write. [FIX] Just fix the wrong check condition to fix the bug. Fixes: e55a0de18572 ("btrfs: rework page locking in __extent_writepage()") CC: stable@vger.kernel.org # 5.16 Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-02erofs: fix ztailpacking on > 4GiB filesystemsGao Xiang
z_idataoff here is an absolute physical offset, so it should use erofs_off_t (64 bits at least). Otherwise, it'll get trimmed and cause the decompresion failure. Link: https://lore.kernel.org/r/20220222033118.20540-1-hsiangkao@linux.alibaba.com Fixes: ab92184ff8f1 ("erofs: add on-disk compressed tail-packing inline support") Reviewed-by: Yue Hu <huyue2@yulong.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-03-02NFS: Cache all entries in the readdirplus replyTrond Myklebust
Even if we're not able to cache all the entries in the readdir buffer, let's ensure that we do prime the dcache. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Optimise away the previous cookie fieldTrond Myklebust
Replace the 'previous cookie' field in struct nfs_entry with the array->last_cookie. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Fix up forced readdirplusTrond Myklebust
Avoid clearing the entire readdir page cache if we're just doing forced readdirplus for the 'ls -l' heuristic. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Convert readdir page cache to use a cookie based indexTrond Myklebust
Instead of using a linear index to address the pages, use the cookie of the first entry, since that is what we use to match the page anyway. This allows us to avoid re-reading the entire cache on a seekdir() type of operation. The latter is very common when re-exporting NFS, and is a major performance drain. The change does affect our duplicate cookie detection, since we can no longer rely on the page index as a linear offset for detecting whether we looped backwards. However since we no longer do a linear search through all the pages on each call to nfs_readdir(), this is less of a concern than it was previously. The other downside is that invalidate_mapping_pages() no longer can use the page index to avoid clearing pages that have been read. A subsequent patch will restore the functionality this provides to the 'ls -l' heuristic. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Clean up page array initialisation/freeTrond Myklebust
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Trace effects of the readdirplus heuristicTrond Myklebust
Enable tracking of when the readdirplus heuristic causes a page cache invalidation. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Trace effects of readdirplus on the dcacheTrond Myklebust
Trace the effects of readdirplus on attribute and dentry revalidation. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Add basic readdir tracingTrond Myklebust
Add tracing to track how often the client goes to the server for updated readdir information. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Don't request readdirplus when revalidation was forcedTrond Myklebust
If the revalidation was forced, due to the presence of a LOOKUP_EXCL or a LOOKUP_REVAL flag, then readdirplus won't help. It also can't help when we're doing a path component lookup. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Readdirplus can't help lookup for case insensitive filesystemsTrond Myklebust
If the filesystem is case insensitive, then readdirplus can't help with cache misses, since it won't return case folded variants of the filename. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFSv4: Ask for a full XDR buffer of readdir goodnessTrond Myklebust
Instead of pretending that we know the ratio of directory info vs readdirplus attribute info, just set the 'dircount' field to the same value as the 'maxcount' field. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Don't ask for readdirplus unless it can help nfs_getattr()Trond Myklebust
If attribute caching is turned off, then use of readdirplus is not going to help stat() performance. Readdirplus also doesn't help if a file is being written to, since we will have to flush those writes in order to sync the mtime/ctime. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Improve heuristic for readdirplusTrond Myklebust
The heuristic for readdirplus is designed to try to detect 'ls -l' and similar patterns. It does so by looking for cache hit/miss patterns in both the attribute cache and in the dcache of the files in a given directory, and then sets a flag for the readdirplus code to interpret. The problem with this approach is that a single attribute or dcache miss can cause the NFS code to force a refresh of the attributes for the entire set of files contained in the directory. To be able to make a more nuanced decision, let's sample the number of hits and misses in the set of open directory descriptors. That allows us to set thresholds at which we start preferring READDIRPLUS over regular READDIR, or at which we start to force a re-read of the remaining readdir cache using READDIRPLUS. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Reduce use of uncached readdirTrond Myklebust
When reading a very large directory, we want to try to keep the page cache up to date if doing so is inexpensive. With the change to allow readdir to continue reading even when the cache is incomplete, we no longer need to fall back to uncached readdir in order to scale to large directories. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Simplify nfs_readdir_xdr_to_array()Trond Myklebust
Recent changes to readdir mean that we can cope with partially filled page cache entries, so we no longer need to rely on looping in nfs_readdir_xdr_to_array(). Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: If the cookie verifier changes, we must invalidate the page cacheTrond Myklebust
Ensure that if the cookie verifier changes when we use the zero-valued cookie, then we invalidate any cached pages. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Adjust the amount of readahead performed by NFS readdirTrond Myklebust
The current NFS readdir code will always try to maximise the amount of readahead it performs on the assumption that we can cache anything that isn't immediately read by the process. There are several cases where this assumption breaks down, including when the 'ls -l' heuristic kicks in to try to force use of readdirplus as a batch replacement for lookup/getattr. This patch therefore tries to tone down the amount of readahead we perform, and adjust it to try to match the amount of data being requested by user space. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Don't advance the page pointer unless the page is fullTrond Myklebust
When we hit the end of the data in the readdir page, we don't want to start filling a new page, unless this one is full. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Don't re-read the entire page cache to find the next cookieTrond Myklebust
If the page cache entry that was last read gets invalidated for some reason, then make sure we can re-create it on the next call to readdir. This, combined with the cache page validation, allows us to reuse the cached value of page-index on successive calls to nfs_readdir. Credit is due to Benjamin Coddington for showing that the concept works, and that it allows for improved cache sharing between processes even in the case where pages are lost due to LRU or active invalidation. Suggested-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-02NFS: Store the change attribute in the directory page cacheTrond Myklebust
Use the change attribute and the first cookie in a directory page cache entry to validate that the page is up to date. Suggested-by: Benjamin Coddington <bcodding@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-03-01exec: cleanup commentsTom Rix
Remove the second 'from'. Replace 'backwords' with 'backwards'. Replace 'visibile' with 'visible'. Signed-off-by: Tom Rix <trix@redhat.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220211160940.2516243-1-trix@redhat.com
2022-03-01fs/binfmt_elf: Refactor load_elf_binary functionAkira Kawata
I delete load_addr because it is not used anymore. And I rename load_addr_set to first_pt_load because it is used only to capture the first iteration of the loop. Signed-off-by: Akira Kawata <akirakawata1@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220127124014.338760-3-akirakawata1@gmail.com
2022-03-01fs/binfmt_elf: Fix AT_PHDR for unusual ELF filesAkira Kawata
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=197921 As pointed out in the discussion of buglink, we cannot calculate AT_PHDR as the sum of load_addr and exec->e_phoff. : The AT_PHDR of ELF auxiliary vectors should point to the memory address : of program header. But binfmt_elf.c calculates this address as follows: : : NEW_AUX_ENT(AT_PHDR, load_addr + exec->e_phoff); : : which is wrong since e_phoff is the file offset of program header and : load_addr is the memory base address from PT_LOAD entry. : : The ld.so uses AT_PHDR as the memory address of program header. In normal : case, since the e_phoff is usually 64 and in the first PT_LOAD region, it : is the correct program header address. : : But if the address of program header isn't equal to the first PT_LOAD : address + e_phoff (e.g. Put the program header in other non-consecutive : PT_LOAD region), ld.so will try to read program header from wrong address : then crash or use incorrect program header. This is because exec->e_phoff is the offset of PHDRs in the file and the address of PHDRs in the memory may differ from it. This patch fixes the bug by calculating the address of program headers from PT_LOADs directly. Signed-off-by: Akira Kawata <akirakawata1@gmail.com> Reported-by: kernel test robot <lkp@intel.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220127124014.338760-2-akirakawata1@gmail.com
2022-03-01binfmt: move more stuff undef CONFIG_COREDUMPAlexey Dobriyan
struct linux_binfmt::core_dump and struct min_coredump::min_coredump are used under CONFIG_COREDUMP only. Shrink those embedded configs a bit. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/YglbIFyN+OtwVyjW@localhost.localdomain
2022-03-01exec: Force single empty string when argv is emptyKees Cook
Quoting[1] Ariadne Conill: "In several other operating systems, it is a hard requirement that the second argument to execve(2) be the name of a program, thus prohibiting a scenario where argc < 1. POSIX 2017 also recommends this behaviour, but it is not an explicit requirement[2]: The argument arg0 should point to a filename string that is associated with the process being started by one of the exec functions. ... Interestingly, Michael Kerrisk opened an issue about this in 2008[3], but there was no consensus to support fixing this issue then. Hopefully now that CVE-2021-4034 shows practical exploitative use[4] of this bug in a shellcode, we can reconsider. This issue is being tracked in the KSPP issue tracker[5]." While the initial code searches[6][7] turned up what appeared to be mostly corner case tests, trying to that just reject argv == NULL (or an immediately terminated pointer list) quickly started tripping[8] existing userspace programs. The next best approach is forcing a single empty string into argv and adjusting argc to match. The number of programs depending on argc == 0 seems a smaller set than those calling execve with a NULL argv. Account for the additional stack space in bprm_stack_limits(). Inject an empty string when argc == 0 (and set argc = 1). Warn about the case so userspace has some notice about the change: process './argc0' launched './argc0' with NULL argv: empty string added Additionally WARN() and reject NULL argv usage for kernel threads. [1] https://lore.kernel.org/lkml/20220127000724.15106-1-ariadne@dereferenced.org/ [2] https://pubs.opengroup.org/onlinepubs/9699919799/functions/exec.html [3] https://bugzilla.kernel.org/show_bug.cgi?id=8408 [4] https://www.qualys.com/2022/01/25/cve-2021-4034/pwnkit.txt [5] https://github.com/KSPP/linux/issues/176 [6] https://codesearch.debian.net/search?q=execve%5C+*%5C%28%5B%5E%2C%5D%2B%2C+*NULL&literal=0 [7] https://codesearch.debian.net/search?q=execlp%3F%5Cs*%5C%28%5B%5E%2C%5D%2B%2C%5Cs*NULL&literal=0 [8] https://lore.kernel.org/lkml/20220131144352.GE16385@xsang-OptiPlex-9020/ Reported-by: Ariadne Conill <ariadne@dereferenced.org> Reported-by: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Christian Brauner <brauner@kernel.org> Cc: Rich Felker <dalias@libc.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Christian Brauner <brauner@kernel.org> Acked-by: Ariadne Conill <ariadne@dereferenced.org> Acked-by: Andy Lutomirski <luto@kernel.org> Link: https://lore.kernel.org/r/20220201000947.2453721-1-keescook@chromium.org
2022-03-01coredump: Also dump first pages of non-executable ELF librariesJann Horn
When I rewrote the VMA dumping logic for coredumps, I changed it to recognize ELF library mappings based on the file being executable instead of the mapping having an ELF header. But turns out, distros ship many ELF libraries as non-executable, so the heuristic goes wrong... Restore the old behavior where FILTER(ELF_HEADERS) dumps the first page of any offset-0 readable mapping that starts with the ELF magic. This fix is technically layer-breaking a bit, because it checks for something ELF-specific in fs/coredump.c; but since we probably want to share this between standard ELF and FDPIC ELF anyway, I guess it's fine? And this also keeps the change small for backporting. Cc: stable@vger.kernel.org Fixes: 429a22e776a2 ("coredump: rework elf/elf_fdpic vma_dump_size() into common helper") Reported-by: Bill Messmer <wmessmer@microsoft.com> Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220126025739.2014888-1-jannh@google.com
2022-03-01ELF: fix overflow in total mapping size calculationAlexey Dobriyan
Kernel assumes that ELF program headers are ordered by mapping address, but doesn't enforce it. It is possible to make mapping size extremely huge by simply shuffling first and last PT_LOAD segments. As long as PT_LOAD segments do not overlap, it is silly to require sorting by v_addr anyway because mmap() doesn't care. Don't assume PT_LOAD segments are sorted and calculate min and max addresses correctly. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Tested-by: "Magnus Groß" <magnus.gross@rwth-aachen.de> Link: https://lore.kernel.org/all/Yfqm7HbucDjPbES+@fractal.localdomain/ Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/lkml/YVmd7D0M6G%2FDcP4O@localhost.localdomain
2022-03-01Merge tag 'binfmt_elf-v5.17-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull binfmt_elf fix from Kees Cook: "This addresses a regression[1] under ia64 where some ET_EXEC binaries were not loading" Link: https://linux-regtracking.leemhuis.info/regzbot/regression/a3edd529-c42d-3b09-135c-7e98a15b150f@leemhuis.info/ [1] - Fix ia64 ET_EXEC loading * tag 'binfmt_elf-v5.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: binfmt_elf: Avoid total_mapping_size for ET_EXEC
2022-03-01pstore: Add prefix to ECC messagesVincent Whitchurch
The "No errors detected" message from the ECC code is shown at the end of the pstore log and can be confusing or misleading, especially since it usually appears just after a kernel crash log which normally means quite the opposite of "no errors". Prefix the message to clarify that this message is only about ECC-detected errors. Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220301144932.89549-1-vincent.whitchurch@axis.com
2022-03-01binfmt_elf: Avoid total_mapping_size for ET_EXECKees Cook
Partially revert commit 5f501d555653 ("binfmt_elf: reintroduce using MAP_FIXED_NOREPLACE"), which applied the ET_DYN "total_mapping_size" logic also to ET_EXEC. At least ia64 has ET_EXEC PT_LOAD segments that are not virtual-address contiguous (but _are_ file-offset contiguous). This would result in a giant mapping attempting to cover the entire span, including the virtual address range hole, and well beyond the size of the ELF file itself, causing the kernel to refuse to load it. For example: $ readelf -lW /usr/bin/gcc ... Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz ... ... LOAD 0x000000 0x4000000000000000 0x4000000000000000 0x00b5a0 0x00b5a0 ... LOAD 0x00b5a0 0x600000000000b5a0 0x600000000000b5a0 0x0005ac 0x000710 ... ... ^^^^^^^^ ^^^^^^^^^^^^^^^^^^ ^^^^^^^^ ^^^^^^^^ File offset range : 0x000000-0x00bb4c 0x00bb4c bytes Virtual address range : 0x4000000000000000-0x600000000000bcb0 0x200000000000bcb0 bytes Remove the total_mapping_size logic for ET_EXEC, which reduces the ET_EXEC MAP_FIXED_NOREPLACE coverage to only the first PT_LOAD (better than nothing), and retains it for ET_DYN. Ironically, this is the reverse of the problem that originally caused problems with MAP_FIXED_NOREPLACE: overlapping PT_LOAD segments. Future work could restore full coverage if load_elf_binary() were to perform mappings in a separate phase from the loading (where it could resolve both overlaps and holes). Cc: Eric Biederman <ebiederm@xmission.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Cc: linux-mm@kvack.org Reported-by: matoro <matoro_bugzilla_kernel@matoro.tk> Fixes: 5f501d555653 ("binfmt_elf: reintroduce using MAP_FIXED_NOREPLACE") Link: https://lore.kernel.org/r/a3edd529-c42d-3b09-135c-7e98a15b150f@leemhuis.info Tested-by: matoro <matoro_mailinglist_kernel@matoro.tk> Link: https://lore.kernel.org/lkml/ce8af9c13bcea9230c7689f3c1e0e2cd@matoro.tk Tested-By: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Link: https://lore.kernel.org/lkml/49182d0d-708b-4029-da5f-bc18603440a6@physik.fu-berlin.de Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
generated by cgit (git 2.34.1) at 2025-09-13 23:43:28 +0000