CVE-2022-50344 Details
Description
In the Linux kernel, the following vulnerability has been resolved: ext4: fix null-ptr-deref in ext4_write_info I caught a null-ptr-deref bug as follows: ================================================================== KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f] CPU: 1 PID: 1589 Comm: umount Not tainted 5.10.0-02219-dirty #339 RIP: 0010:ext4_write_info+0x53/0x1b0 [...] Call Trace: dquot_writeback_dquots+0x341/0x9a0 ext4_sync_fs+0x19e/0x800 __sync_filesystem+0x83/0x100 sync_filesystem+0x89/0xf0 generic_shutdown_super+0x79/0x3e0 kill_block_super+0xa1/0x110 deactivate_locked_super+0xac/0x130 deactivate_super+0xb6/0xd0 cleanup_mnt+0x289/0x400 __cleanup_mnt+0x16/0x20 task_work_run+0x11c/0x1c0 exit_to_user_mode_prepare+0x203/0x210 syscall_exit_to_user_mode+0x5b/0x3a0 do_syscall_64+0x59/0x70 entry_SYSCALL_64_after_hwframe+0x44/0xa9 ================================================================== Above issue may happen as follows: ------------------------------------- exit_to_user_mode_prepare task_work_run __cleanup_mnt cleanup_mnt deactivate_super deactivate_locked_super kill_block_super generic_shutdown_super shrink_dcache_for_umount dentry = sb->s_root sb->s_root = NULL <--- Here set NULL sync_filesystem __sync_filesystem sb->s_op->sync_fs > ext4_sync_fs dquot_writeback_dquots sb->dq_op->write_info > ext4_write_info ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2) d_inode(sb->s_root) s_root->d_inode <--- Null pointer dereference To solve this problem, we use ext4_journal_start_sb directly to avoid s_root being used.
A null pointer dereference vulnerability has been identified in the ext4 file system implementation of the Linux kernel. This issue arises in the ext4_write_info function, where the file system's root directory inode can be set to null. When the function attempts to access the inode, it leads to a null pointer dereference, causing a crash. The vulnerability is present in several versions of the Linux kernel, including 5.10.0-02219-dirty.
Users can upgrade to the latest version of the Linux kernel where this vulnerability has been patched. Instructions for upgrading the Linux kernel can be found in the official Linux kernel documentation.
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Jan 14, 2026References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://git.kernel.org/stable/c/3638aa1c7d87c0ca0aef23cf58cae2c48e7daca4 | kernel.org | Patch |
| https://git.kernel.org/stable/c/4a657319cfabd6199fd0b7b65bbebf6ded7a11c1 | kernel.org | Patch |
| https://git.kernel.org/stable/c/533c60a0b97cee5daab376933f486207e6680fb7 | kernel.org | Patch |
| https://git.kernel.org/stable/c/947264e00c46de19a016fd81218118c708fed2f3 | kernel.org | Patch |
| https://git.kernel.org/stable/c/bb420e8afc854d2a1caaa23a0c129839acfb7888 | kernel.org | Patch |
| https://git.kernel.org/stable/c/dc451578446afd03c0c21913993c08898a691435 | kernel.org | Patch |
| https://git.kernel.org/stable/c/f34ab95162763cd7352f46df169296eec28b688d | kernel.org | Patch |
| https://git.kernel.org/stable/c/f4b5ff0b794aa94afac7269c494550ca2f66511b | kernel.org | Patch |
| https://git.kernel.org/stable/c/f9c1f248607d5546075d3f731e7607d5571f2b60 | kernel.org | Patch |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-476 | NULL Pointer Dereference | [email protected] |
| CWE-476 | NULL Pointer Dereference | CISA-ADP |
Affected Products
| Product | Versions |
|---|---|
| linux linux kernel | < 4.9.331 >= 4.10, < 4.14.296 >= 4.15, < 4.19.262 >= 4.20, < 5.4.220 >= 5.5, < 5.10.150 >= 5.11, < 5.15.75 >= 5.16, < 5.19.17 >= 6.0, < 6.0.3 |
CPE
Remediation
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Change History
5 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | kernel.org |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Jan 14, 2026 | CVE Modified | CISA-ADP |
| Dec 1, 2025 | Initial Analysis | [email protected] |
| Sep 16, 2025 | New CVE Received | kernel.org |