CVE-2026-80644

Description

In the Linux kernel, the following vulnerability has been resolved: ocfs2: don't BUG_ON an invalid journal dinode [BUG] A fuzzed OCFS2 image can corrupt the current slot journal dinode while mount is still in progress. The mount path first reports the invalid journal block and then crashes in shutdown: kernel BUG at fs/ocfs2/journal.c:1034! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI RIP: 0010:ocfs2_journal_toggle_dirty+0x2d6/0x340 fs/ocfs2/journal.c:1034 Call Trace: ocfs2_journal_shutdown+0x414/0xc30 fs/ocfs2/journal.c:1116 ocfs2_mount_volume fs/ocfs2/super.c:1785 [inline] ocfs2_fill_super+0x30a9/0x3cd0 fs/ocfs2/super.c:1083 get_tree_bdev_flags+0x38b/0x640 fs/super.c:1698 get_tree_bdev+0x24/0x40 fs/super.c:1721 ocfs2_get_tree+0x21/0x30 fs/ocfs2/super.c:1184 vfs_get_tree+0x9a/0x370 fs/super.c:1758 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3642 [inline] do_new_mount fs/namespace.c:3718 [inline] path_mount+0x5b8/0x1ea0 fs/namespace.c:4028 do_mount fs/namespace.c:4041 [inline] __do_sys_mount fs/namespace.c:4229 [inline] __se_sys_mount fs/namespace.c:4206 [inline] __x64_sys_mount+0x282/0x320 fs/namespace.c:4206 ... [CAUSE] ocfs2_journal_toggle_dirty() used to return -EIO when journal->j_bh no longer contained a valid dinode, because the startup and shutdown paths already handled that failure. Commit 10995aa2451a ("ocfs2: Morph the haphazard OCFS2_IS_VALID_DINODE() checks.") changed the check to a BUG_ON() under the assumption that the journal dinode had already been validated. That turns an unexpected invalid journal dinode during mount teardown into a kernel crash instead of a normal mount failure. [FIX] Replace the BUG_ON() with WARN_ON() and return -EIO. This keeps the invariant warning for debugging, but restores the original behavior of failing startup or shutdown cleanly instead of panicking the kernel.

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EPSS — Exploit Prediction

0.0018

Probability of exploitation

0.07%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/12c32a7350b670aaaaf2e01583d8648ec0c9755c https://git.kernel.org/stable/c/3852478d34c7baa490ba9c7374ee901a56eea577 https://git.kernel.org/stable/c/5b33f99f3e48465bd93219495381a5aef4fa967f https://git.kernel.org/stable/c/86509c5296fe46ad6bcdd83931a53c2c6b7913a8 https://git.kernel.org/stable/c/a06eec15596e5801bad59ad16cd2bf4f0fa839a1 https://git.kernel.org/stable/c/b460f8d01a12061853d02c8fb693fb42450acd7d https://git.kernel.org/stable/c/bf1d59cf2ac8a1730607ebaa0bc0dc6d00f197d0 https://git.kernel.org/stable/c/c0438198c28b1d22c272751af5e717c11d9fa8dd

Frequently Asked Questions

What is CVE-2026-80644? +

In the Linux kernel, the following vulnerability has been resolved: ocfs2: don't BUG_ON an invalid journal dinode [BUG] A fuzzed OCFS2 image can corrupt the current slot journal dinode while mount is still in progress. The mount path first reports the invalid journal block and then crashes in shutdown: kernel BUG at fs/ocfs2/journal.c:1034! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI RIP: 0010:ocfs2_journal_toggle_dirty+0x2d6/0x340 fs/ocfs2/journal.c:1034 Call Trace: ocfs2_journal_shutdown+0x414/0xc30 fs/ocfs2/journal.c:1116 ocfs2_mount_volume fs/ocfs2/super.c:1785 [inline] ocfs2_fill_super+0x30a9/0x3cd0 fs/ocfs2/super.c:1083 get_tree_bdev_flags+0x38b/0x640 fs/super.c:1698 get_tree_bdev+0x24/0x40 fs/super.c:1721 ocfs2_get_tree+0x21/0x30 fs/ocfs2/super.c:1184 vfs_get_tree+0x9a/0x370 fs/super.c:1758 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3642 [inline] do_new_mount fs/namespace.c:3718 [inline] path_mount+0x5b8/0x1ea0 fs/namespace.c:4028 do_mount fs/namespace.c:4041 [inline] __do_sys_mount fs/namespace.c:4229 [inline] __se_sys_mount fs/namespace.c:4206 [inline] __x64_sys_mount+0x282/0x320 fs/namespace.c:4206 ... [CAUSE] ocfs2_journal_toggle_dirty() used to return -EIO when journal->j_bh no longer contained a valid dinode, because the startup and shutdown paths already handled that failure. Commit 10995aa2451a ("ocfs2: Morph the haphazard OCFS2_IS_VALID_DINODE() checks.") changed the check to a BUG_ON() under the assumption that the journal dinode had already been validated. That turns an unexpected invalid journal dinode during mount teardown into a kernel crash instead of a normal mount failure. [FIX] Replace the BUG_ON() with WARN_ON() and return -EIO. This keeps the invariant warning for debugging, but restores the original behavior of failing startup or shutdown cleanly instead of panicking the kernel.

How do I check if I'm vulnerable to CVE-2026-80644? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.