cbcvebase.
CVE-2021-47335
published 2024-05-21

CVE-2021-47335: 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…

PriorityP421medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.23%
14.2th percentile
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.

Affected

13 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.14.6-1 (bookworm)linux 5.14.6-1 (bookworm)
linuxlinux
linuxlinux>= 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 < 86786603014e0a22d0d6af8e80ae4b868792704886786603014e0a22d0d6af8e80ae4b8687927048
linuxlinux>= 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 < 79fa5d944c875711253a23b8155b36883c69640979fa5d944c875711253a23b8155b36883c696409
linuxlinux>= 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 < e472b276a0d2180808009be38105e12754432e2ae472b276a0d2180808009be38105e12754432e2a
linuxlinux>= 98e4da8ca301e062d79ae168c67e56f3c3de3ce4 < cad83c968c2ebe97905f900326988ed37146c347cad83c968c2ebe97905f900326988ed37146c347
linuxlinux_kernel< 5.10.515.10.51
linuxlinux_kernel>= 0 < 5.10.70-15.10.70-1
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 0 < 5.14.6-15.14.6-1
linuxlinux_kernel>= 5.11 < 5.12.185.12.18
linuxlinux_kernel>= 5.13 < 5.13.35.13.3

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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