In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid racing on fsync_entry_slab by multi filesystem instances
As syzbot reported, there is an use-after-free issue during f2fs recovery:
Use-after-free write at 0xffff88823bc16040 (in kfence-#10):
kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
mount_bdev+0x26c/0x3a0 fs/super.c:1367
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1497
do_new_mount fs/namespace.c:2905 [inline]
path_mount+0x196f/0x2be0 fs/namespace.c:3235
do_mount fs/namespace.c:3248 [inline]
__do_sys_mount fs/namespace.c:3456 [inline]
__se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0x44/0xae
The root cause is multi f2fs filesystem instances can race on accessing
global fsync_entry_slab pointer, result in use-after-free issue of slab
cache, fixes to init/destroy this slab cache only once during module
init/destroy procedure to avoid this issue.
[
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"fs/f2fs/f2fs.h",
"fs/f2fs/recovery.c",
"fs/f2fs/super.c"
],
"versions": [
{
"version": "1da177e4c3f4",
"lessThan": "86786603014e",
"status": "affected",
"versionType": "git"
},
{
"version": "1da177e4c3f4",
"lessThan": "79fa5d944c87",
"status": "affected",
"versionType": "git"
},
{
"version": "1da177e4c3f4",
"lessThan": "e472b276a0d2",
"status": "affected",
"versionType": "git"
},
{
"version": "1da177e4c3f4",
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"status": "affected",
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}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"fs/f2fs/f2fs.h",
"fs/f2fs/recovery.c",
"fs/f2fs/super.c"
],
"versions": [
{
"version": "5.10.51",
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.12.18",
"lessThanOrEqual": "5.12.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.13.3",
"lessThanOrEqual": "5.13.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.14",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
]