Description
In the Linux kernel, the following vulnerability has been resolved: f2fs: use global inline_xattr_slab instead of per-sb slab cache As Hong Yun reported in mailing list: loop7: detected capacity change from 0 to 131072 ------------[ cut here ]------------ kmem_cache of name 'f2fs_xattr_entry-7:7' already exists WARNING: CPU: 0 PID: 24426 at mm/slab_common.c:110 kmem_cache_sanity_check mm/slab_common.c:109 [inline] WARNING: CPU: 0 PID: 24426 at mm/slab_common.c:110 __kmem_cache_create_args+0xa6/0x320 mm/slab_common.c:307 CPU: 0 UID: 0 PID: 24426 Comm: syz.7.1370 Not tainted 6.17.0-rc4 #1 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:kmem_cache_sanity_check mm/slab_common.c:109 [inline] RIP: 0010:__kmem_cache_create_args+0xa6/0x320 mm/slab_common.c:307 Call Trace: __kmem_cache_create include/linux/slab.h:353 [inline] f2fs_kmem_cache_create fs/f2fs/f2fs.h:2943 [inline] f2fs_init_xattr_caches+0xa5/0xe0 fs/f2fs/xattr.c:843 f2fs_fill_super+0x1645/0x2620 fs/f2fs/super.c:4918 get_tree_bdev_flags+0x1fb/0x260 fs/super.c:1692 vfs_get_tree+0x43/0x140 fs/super.c:1815 do_new_mount+0x201/0x550 fs/namespace.c:3808 do_mount fs/namespace.c:4136 [inline] __do_sys_mount fs/namespace.c:4347 [inline] __se_sys_mount+0x298/0x2f0 fs/namespace.c:4324 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x8e/0x3a0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e The bug can be reproduced w/ below scripts: - mount /dev/vdb /mnt1 - mount /dev/vdc /mnt2 - umount /mnt1 - mounnt /dev/vdb /mnt1 The reason is if we created two slab caches, named f2fs_xattr_entry-7:3 and f2fs_xattr_entry-7:7, and they have the same slab size. Actually, slab system will only create one slab cache core structure which has slab name of "f2fs_xattr_entry-7:3", and two slab caches share the same structure and cache address. So, if we destroy f2fs_xattr_entry-7:3 cache w/ cache address, it will decrease reference count of slab cache, rather than release slab cache entirely, since there is one more user has referenced the cache. Then, if we try to create slab cache w/ name "f2fs_xattr_entry-7:3" again, slab system will find that there is existed cache which has the same name and trigger the warning. Let's changes to use global inline_xattr_slab instead of per-sb slab cache for fixing.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
a999150f4fe3abbb7efd05411fd5b460be699943 to < 93d30fe19660dec6bf1bd3d5c186c1c737b21aa5affecteda999150f4fe3abbb7efd05411fd5b460be699943 to < 474cc3ed37436ddfd63cac8dbffe3b1e219e9100affecteda999150f4fe3abbb7efd05411fd5b460be699943 to < 72ce19dfed162da6e430467333b2da70471d08a4affecteda999150f4fe3abbb7efd05411fd5b460be699943 to < be4c3a3c6c2304a8fcd14095d18d26f0cc4e222aaffecteda999150f4fe3abbb7efd05411fd5b460be699943 to < 1eb0b130196bcbc56c5c80c83139fa70c0aa82c5affecteda999150f4fe3abbb7efd05411fd5b460be699943 to < e6d828eae00ec192e18c2ddaa2fd32050a96048aaffecteda999150f4fe3abbb7efd05411fd5b460be699943 to < 1f27ef42bb0b7c0740c5616ec577ec188b8a1d05affected
Linux Linux
Default version status: affected
5.7affected0 to < 5.7unaffected5.10.248 to ≤ 5.10.*unaffected5.15.198 to ≤ 5.15.*unaffected6.1.160 to ≤ 6.1.*unaffected6.6.120 to ≤ 6.6.*unaffected6.12.64 to ≤ 6.12.*unaffected6.18.3 to ≤ 6.18.*unaffected6.19 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/93d30fe19660dec6bf1bd3d5c186c1c737b21aa5 ↗
- https://git.kernel.org/stable/c/474cc3ed37436ddfd63cac8dbffe3b1e219e9100 ↗
- https://git.kernel.org/stable/c/72ce19dfed162da6e430467333b2da70471d08a4 ↗
- https://git.kernel.org/stable/c/be4c3a3c6c2304a8fcd14095d18d26f0cc4e222a ↗
- https://git.kernel.org/stable/c/1eb0b130196bcbc56c5c80c83139fa70c0aa82c5 ↗
- https://git.kernel.org/stable/c/e6d828eae00ec192e18c2ddaa2fd32050a96048a ↗
- https://git.kernel.org/stable/c/1f27ef42bb0b7c0740c5616ec577ec188b8a1d05 ↗