cbcvebase.
CVE-2022-50344
published 2025-09-16

CVE-2022-50344: 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…

PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.15%
4.6th percentile
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 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.

Affected

23 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.0.3-1 (bookworm)linux 6.0.3-1 (bookworm)
linuxlinux——
linuxlinux>= a1177825719ccef3f76ef39bbfd5ebb6087d53c7 < dc451578446afd03c0c21913993c08898a691435dc451578446afd03c0c21913993c08898a691435
linuxlinux>= a1177825719ccef3f76ef39bbfd5ebb6087d53c7 < f4b5ff0b794aa94afac7269c494550ca2f66511bf4b5ff0b794aa94afac7269c494550ca2f66511b
linuxlinux>= a1177825719ccef3f76ef39bbfd5ebb6087d53c7 < 947264e00c46de19a016fd81218118c708fed2f3947264e00c46de19a016fd81218118c708fed2f3
linuxlinux>= a1177825719ccef3f76ef39bbfd5ebb6087d53c7 < 3638aa1c7d87c0ca0aef23cf58cae2c48e7daca43638aa1c7d87c0ca0aef23cf58cae2c48e7daca4
linuxlinux>= a1177825719ccef3f76ef39bbfd5ebb6087d53c7 < f34ab95162763cd7352f46df169296eec28b688df34ab95162763cd7352f46df169296eec28b688d
linuxlinux>= a1177825719ccef3f76ef39bbfd5ebb6087d53c7 < 533c60a0b97cee5daab376933f486207e6680fb7533c60a0b97cee5daab376933f486207e6680fb7
linuxlinux>= a1177825719ccef3f76ef39bbfd5ebb6087d53c7 < 4a657319cfabd6199fd0b7b65bbebf6ded7a11c14a657319cfabd6199fd0b7b65bbebf6ded7a11c1
linuxlinux>= a1177825719ccef3f76ef39bbfd5ebb6087d53c7 < bb420e8afc854d2a1caaa23a0c129839acfb7888bb420e8afc854d2a1caaa23a0c129839acfb7888
linuxlinux>= a1177825719ccef3f76ef39bbfd5ebb6087d53c7 < f9c1f248607d5546075d3f731e7607d5571f2b60f9c1f248607d5546075d3f731e7607d5571f2b60
linuxlinux_kernel< 4.9.3314.9.331
linuxlinux_kernel>= 0 < 5.10.158-15.10.158-1
linuxlinux_kernel>= 0 < 6.0.3-16.0.3-1
linuxlinux_kernel>= 0 < 6.0.3-16.0.3-1
linuxlinux_kernel>= 0 < 6.0.3-16.0.3-1
linuxlinux_kernel>= 4.10 < 4.14.2964.14.296
linuxlinux_kernel>= 4.15 < 4.19.2624.19.262
linuxlinux_kernel>= 4.20 < 5.4.2205.4.220
linuxlinux_kernel>= 5.11 < 5.15.755.15.75
linuxlinux_kernel>= 5.16 < 5.19.175.19.17
linuxlinux_kernel>= 5.5 < 5.10.1505.10.150
linuxlinux_kernel>= 6.0 < 6.0.36.0.3

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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