In the Linux kernel, the following vulnerability has been resolved:
f2fs: use global inlinexattrslab instead of per-sb slab cache
As Hong Yun reported in mailing list:
loop7: detected capacity change from 0 to 131072 ------------[ cut here ]------------ kmemcache of name 'f2fsxattrentry-7:7' already exists WARNING: CPU: 0 PID: 24426 at mm/slabcommon.c:110 kmemcachesanitycheck mm/slabcommon.c:109 [inline] WARNING: CPU: 0 PID: 24426 at mm/slabcommon.c:110 kmemcachecreateargs+0xa6/0x320 mm/slabcommon.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:kmemcachesanitycheck mm/slabcommon.c:109 [inline] RIP: 0010:kmemcachecreateargs+0xa6/0x320 mm/slabcommon.c:307 Call Trace: _kmemcachecreate include/linux/slab.h:353 [inline] f2fskmemcachecreate fs/f2fs/f2fs.h:2943 [inline] f2fsinitxattrcaches+0xa5/0xe0 fs/f2fs/xattr.c:843 f2fsfillsuper+0x1645/0x2620 fs/f2fs/super.c:4918 gettreebdevflags+0x1fb/0x260 fs/super.c:1692 vfsgettree+0x43/0x140 fs/super.c:1815 donewmount+0x201/0x550 fs/namespace.c:3808 domount fs/namespace.c:4136 [inline] _dosysmount fs/namespace.c:4347 [inline] _sesysmount+0x298/0x2f0 fs/namespace.c:4324 dosyscallx64 arch/x86/entry/syscall64.c:63 [inline] dosyscall64+0x8e/0x3a0 arch/x86/entry/syscall64.c:94 entrySYSCALL64afterhwframe+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 f2fsxattrentry-7:3 and f2fsxattrentry-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 "f2fsxattrentry-7:3", and two slab caches share the same structure and cache address.
So, if we destroy f2fsxattrentry-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 "f2fsxattrentry-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 inlinexattrslab instead of per-sb slab cache for fixing.
{
"cna_assigner": "Linux",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71105.json"
}