ghsa-x64m-4w9m-w2j3
Vulnerability from github
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": [],
"aliases": [
"CVE-2025-40235"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-12-04T16:16:16Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: directly free partially initialized fs_info in btrfs_check_leaked_roots()\n\nIf fs_info-\u003esuper_copy or fs_info-\u003esuper_for_commit allocated failed in\nbtrfs_get_tree_subvol(), then no need to call btrfs_free_fs_info().\nOtherwise btrfs_check_leaked_roots() would access NULL pointer because\nfs_info-\u003eallocated_roots had not been initialised.\n\nsyzkaller reported the following information:\n ------------[ cut here ]------------\n BUG: unable to handle page fault for address: fffffffffffffbb0\n #PF: supervisor read access in kernel mode\n #PF: error_code(0x0000) - not-present page\n PGD 64c9067 P4D 64c9067 PUD 64cb067 PMD 0\n Oops: Oops: 0000 [#1] SMP KASAN PTI\n CPU: 0 UID: 0 PID: 1402 Comm: syz.1.35 Not tainted 6.15.8 #4 PREEMPT(lazy)\n Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), (...)\n RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]\n RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]\n RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]\n RIP: 0010:refcount_read include/linux/refcount.h:170 [inline]\n RIP: 0010:btrfs_check_leaked_roots+0x18f/0x2c0 fs/btrfs/disk-io.c:1230\n [...]\n Call Trace:\n \u003cTASK\u003e\n btrfs_free_fs_info+0x310/0x410 fs/btrfs/disk-io.c:1280\n btrfs_get_tree_subvol+0x592/0x6b0 fs/btrfs/super.c:2029\n btrfs_get_tree+0x63/0x80 fs/btrfs/super.c:2097\n vfs_get_tree+0x98/0x320 fs/super.c:1759\n do_new_mount+0x357/0x660 fs/namespace.c:3899\n path_mount+0x716/0x19c0 fs/namespace.c:4226\n do_mount fs/namespace.c:4239 [inline]\n __do_sys_mount fs/namespace.c:4450 [inline]\n __se_sys_mount fs/namespace.c:4427 [inline]\n __x64_sys_mount+0x28c/0x310 fs/namespace.c:4427\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x92/0x180 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n RIP: 0033:0x7f032eaffa8d\n [...]",
"id": "GHSA-x64m-4w9m-w2j3",
"modified": "2025-12-04T18:30:52Z",
"published": "2025-12-04T18:30:52Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-40235"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/0c2b2d4d053e9840e6da6ed581befa20309f281a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/17679ac6df6c4830ba711835aa8cf961be36cfa1"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b1c2b4e6ffd307720ab6ce42f6749b0c02ba0a73"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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