cbcvebase.
CVE-2025-40235
published 2025-12-04

CVE-2025-40235: In the Linux kernel, the following vulnerability has been resolved: btrfs: directly free partially initialized fs_info in btrfs_check_leaked_roots() If…

PriorityP421high7.8
EPSS
0.19%
9.3th percentile
In the Linux kernel, the following vulnerability has been resolved: btrfs: directly free partially initialized fs_info in btrfs_check_leaked_roots() If fs_info->super_copy or fs_info->super_for_commit allocated failed in btrfs_get_tree_subvol(), then no need to call btrfs_free_fs_info(). Otherwise btrfs_check_leaked_roots() would access NULL pointer because fs_info->allocated_roots had not been initialised. syzkaller reported the following information: ------------[ cut here ]------------ BUG: unable to handle page fault for address: fffffffffffffbb0 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 64c9067 P4D 64c9067 PUD 64cb067 PMD 0 Oops: Oops: 0000 [#1] SMP KASAN PTI CPU: 0 UID: 0 PID: 1402 Comm: syz.1.35 Not tainted 6.15.8 #4 PREEMPT(lazy) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), (...) RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline] RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline] RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline] RIP: 0010:refcount_read include/linux/refcount.h:170 [inline] RIP: 0010:btrfs_check_leaked_roots+0x18f/0x2c0 fs/btrfs/disk-io.c:1230 [...] Call Trace: btrfs_free_fs_info+0x310/0x410 fs/btrfs/disk-io.c:1280 btrfs_get_tree_subvol+0x592/0x6b0 fs/btrfs/super.c:2029 btrfs_get_tree+0x63/0x80 fs/btrfs/super.c:2097 vfs_get_tree+0x98/0x320 fs/super.c:1759 do_new_mount+0x357/0x660 fs/namespace.c:3899 path_mount+0x716/0x19c0 fs/namespace.c:4226 do_mount fs/namespace.c:4239 [inline] __do_sys_mount fs/namespace.c:4450 [inline] __se_sys_mount fs/namespace.c:4427 [inline] __x64_sys_mount+0x28c/0x310 fs/namespace.c:4427 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x92/0x180 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f032eaffa8d [...]

Affected

14 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.17.6-1 (forky)linux 6.17.6-1 (forky)
linuxlinux
linuxlinux>= 3bb17a25bcb09abbd667c6ac86c7c9109ae82bcd < b1c2b4e6ffd307720ab6ce42f6749b0c02ba0a73b1c2b4e6ffd307720ab6ce42f6749b0c02ba0a73
linuxlinux>= 3bb17a25bcb09abbd667c6ac86c7c9109ae82bcd < 0c2b2d4d053e9840e6da6ed581befa20309f281a0c2b2d4d053e9840e6da6ed581befa20309f281a
linuxlinux>= 3bb17a25bcb09abbd667c6ac86c7c9109ae82bcd < 17679ac6df6c4830ba711835aa8cf961be36cfa117679ac6df6c4830ba711835aa8cf961be36cfa1
linuxlinux_kernel>= 0 < 6.12.57-16.12.57-1
linuxlinux_kernel>= 0 < 6.17.6-16.17.6-1
linuxlinux_kernel>= 0 < 6.8.0-106.1066.8.0-106.106
linuxlinux_kernel>= 0 < 6.17.0-14.146.17.0-14.14
linuxlinux_kernel>= 6.13.0 < 6.17.66.17.6
linuxlinux_kernel>= 6.8.0 < 6.12.566.12.56
ubuntulinux-aws
ubuntulinux-oracle
ubuntulinux-xilinx

CVSS provenance

vendor_ubuntu7.8HIGH
osv3.2LOW
vendor_redhat5.5LOW
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