{"id":"DEBIAN-CVE-2025-40235","details":"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-\u003esuper_copy or fs_info-\u003esuper_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-\u003eallocated_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:    \u003cTASK\u003e    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   [...]","modified":"2026-08-27T22:48:54.827903623Z","published":"2025-12-04T16:16:16.407Z","upstream":["CVE-2025-40235"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2025-40235"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.57-1"}]}],"versions":["6.12.38-1","6.12.41-1","6.12.43-1","6.12.43-1~bpo12+1","6.12.48-1","6.12.57-1~bpo12+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-40235.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.17.6-1"}]}],"versions":["6.12.100-1","6.12.101-1","6.12.105-1","6.12.38-1","6.12.41-1","6.12.43-1","6.12.43-1~bpo12+1","6.12.48-1","6.12.57-1","6.12.57-1~bpo12+1","6.12.63-1","6.12.63-1~bpo12+1","6.12.69-1","6.12.69-1~bpo12+1","6.12.73-1","6.12.73-1~bpo12+1","6.12.74-1","6.12.74-2","6.12.74-2~bpo12+1","6.12.85-1","6.12.85-1~bpo12+1","6.12.86-1","6.12.86-1~bpo12+1","6.12.88-1","6.12.88-1~bpo12+1","6.12.90-1","6.12.90-1~bpo12+1","6.12.90-2","6.12.90-2~bpo12+1","6.12.94-1","6.12.94-1~bpo12+1","6.12.95-1","6.12.95-1~bpo12+1","6.12.96-1","6.13.10-1~exp1","6.13.11-1~exp1","6.13.2-1~exp1","6.13.3-1~exp1","6.13.4-1~exp1","6.13.5-1~exp1","6.13.6-1~exp1","6.13.7-1~exp1","6.13.8-1~exp1","6.13.9-1~exp1","6.13~rc6-1~exp1","6.13~rc7-1~exp1","6.14.3-1~exp1","6.14.5-1~exp1","6.14.6-1~exp1","6.15-1~exp1","6.15.1-1~exp1","6.15.2-1~exp1","6.15.3-1~exp1","6.15.4-1~exp1","6.15.5-1~exp1","6.15.6-1~exp1","6.15~rc7-1~exp1","6.16-1~exp1","6.16.1-1~exp1","6.16.10-1","6.16.11-1","6.16.12-1","6.16.12-1~bpo13+1","6.16.12-2","6.16.3-1","6.16.3-1~bpo13+1","6.16.5-1","6.16.6-1","6.16.7-1","6.16.8-1","6.16.9-1","6.16~rc7-1~exp1","6.17.2-1~exp1","6.17.5-1~exp1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-40235.json"}}],"schema_version":"1.9.0"}