cbcvebase.
CVE-2025-40246
published 2025-12-04

CVE-2025-40246: In the Linux kernel, the following vulnerability has been resolved: xfs: fix out of bounds memory read error in symlink repair xfs/286 produced this report on…

PriorityP426high7.2
EPSS
0.19%
9.4th percentile
In the Linux kernel, the following vulnerability has been resolved: xfs: fix out of bounds memory read error in symlink repair xfs/286 produced this report on my test fleet: BUG: KFENCE: out-of-bounds read in memcpy_orig+0x54/0x110 Out-of-bounds read at 0xffff88843fe9e038 (184B right of kfence-#184): memcpy_orig+0x54/0x110 xrep_symlink_salvage_inline+0xb3/0xf0 [xfs] xrep_symlink_salvage+0x100/0x110 [xfs] xrep_symlink+0x2e/0x80 [xfs] xrep_attempt+0x61/0x1f0 [xfs] xfs_scrub_metadata+0x34f/0x5c0 [xfs] xfs_ioc_scrubv_metadata+0x387/0x560 [xfs] xfs_file_ioctl+0xe23/0x10e0 [xfs] __x64_sys_ioctl+0x76/0xc0 do_syscall_64+0x4e/0x1e0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 kfence-#184: 0xffff88843fe9df80-0xffff88843fe9dfea, size=107, cache=kmalloc-128 allocated by task 3470 on cpu 1 at 263329.131592s (192823.508886s ago): xfs_init_local_fork+0x79/0xe0 [xfs] xfs_iformat_local+0xa4/0x170 [xfs] xfs_iformat_data_fork+0x148/0x180 [xfs] xfs_inode_from_disk+0x2cd/0x480 [xfs] xfs_iget+0x450/0xd60 [xfs] xfs_bulkstat_one_int+0x6b/0x510 [xfs] xfs_bulkstat_iwalk+0x1e/0x30 [xfs] xfs_iwalk_ag_recs+0xdf/0x150 [xfs] xfs_iwalk_run_callbacks+0xb9/0x190 [xfs] xfs_iwalk_ag+0x1dc/0x2f0 [xfs] xfs_iwalk_args.constprop.0+0x6a/0x120 [xfs] xfs_iwalk+0xa4/0xd0 [xfs] xfs_bulkstat+0xfa/0x170 [xfs] xfs_ioc_fsbulkstat.isra.0+0x13a/0x230 [xfs] xfs_file_ioctl+0xbf2/0x10e0 [xfs] __x64_sys_ioctl+0x76/0xc0 do_syscall_64+0x4e/0x1e0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 CPU: 1 UID: 0 PID: 1300113 Comm: xfs_scrub Not tainted 6.18.0-rc4-djwx #rc4 PREEMPT(lazy) 3d744dd94e92690f00a04398d2bd8631dcef1954 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-4.module+el8.8.0+21164+ed375313 04/01/2014 On further analysis, I realized that the second parameter to min() is not correct. xfs_ifork::if_bytes is the size of the xfs_ifork::if_data buffer. if_bytes can be smaller than the data fork size because: (a) the forkoff code tries to keep the data area as large as possible (b) for symbolic links,

Affected

10 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.17.10-1 (forky)linux 6.17.10-1 (forky)
linuxlinux
linuxlinux>= 2651923d8d8db00a57665822f017fa7c76758044 < 7c2d68e091584149fe89bcbaf9b99b3162d46ee77c2d68e091584149fe89bcbaf9b99b3162d46ee7
linuxlinux>= 2651923d8d8db00a57665822f017fa7c76758044 < 81a8685cac4bf081c93a7df591644f4f80240bb981a8685cac4bf081c93a7df591644f4f80240bb9
linuxlinux>= 2651923d8d8db00a57665822f017fa7c76758044 < 678e1cc2f482e0985a0613ab4a5bf89c497e5acc678e1cc2f482e0985a0613ab4a5bf89c497e5acc
linuxlinux_kernel>= 0 < 6.12.63-16.12.63-1
linuxlinux_kernel>= 0 < 6.17.10-16.17.10-1
linuxlinux_kernel>= 0 < 6.17.0-19.196.17.0-19.19
linuxlinux_kernel>= 6.10.0 < 6.12.606.12.60
linuxlinux_kernel>= 6.13.0 < 6.17.106.17.10

CVSS provenance

osv7.2HIGH
vendor_ubuntu7.2HIGH
vendor_redhat7.1MEDIUM
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