Linux Kernel up to 5.15.32/5.16.18/5.17.1 umount infinite loop

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.15.32/5.16.18/5.17.1 and classified as problematic. This affects an unknown part of the component umount. Executing a manipulation can lead to infinite loop. The identification of this vulnerability is CVE-2022-49281. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.15.32/5.16.18/5.17.1. It has been declared as problematic. This vulnerability affects an unknown code of the component umount. The manipulation with an unknown input leads to a infinite loop vulnerability. The CWE definition for the vulnerability is CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. As an impact it is known to affect availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: cifs: fix handlecache and multiuser In multiuser each individual user has their own tcon structure for the share and thus their own handle for a cached directory. When we umount such a share we much make sure to release the pinned down dentry for each such tcon and not just the master tcon. Otherwise we will get nasty warnings on umount that dentries are still in use: [ 3459.590047] BUG: Dentry 00000000115c6f41{i=12000000019d95,n=/} still in use\ (2) [unmount of cifs cifs] ... [ 3459.590492] Call Trace: [ 3459.590500] d_walk+0x61/0x2a0 [ 3459.590518] ? shrink_lock_dentry.part.0+0xe0/0xe0 [ 3459.590526] shrink_dcache_for_umount+0x49/0x110 [ 3459.590535] generic_shutdown_super+0x1a/0x110 [ 3459.590542] kill_anon_super+0x14/0x30 [ 3459.590549] cifs_kill_sb+0xf5/0x104 [cifs] [ 3459.590773] deactivate_locked_super+0x36/0xa0 [ 3459.590782] cleanup_mnt+0x131/0x190 [ 3459.590789] task_work_run+0x5c/0x90 [ 3459.590798] exit_to_user_mode_loop+0x151/0x160 [ 3459.590809] exit_to_user_mode_prepare+0x83/0xd0 [ 3459.590818] syscall_exit_to_user_mode+0x12/0x30 [ 3459.590828] do_syscall_64+0x48/0x90 [ 3459.590833] entry_SYSCALL_64_after_hwframe+0x44/0xae

The weakness was shared by The Master. The advisory is available at git.kernel.org. This vulnerability was named CVE-2022-49281 since 02/26/2025. The exploitation appears to be difficult. The technical details are unknown and an exploit is not available.

Upgrading to version 5.15.33, 5.16.19 or 5.17.2 eliminates this vulnerability. Applying the patch 2fafbc198613823943c106d1ec9b516da692059f/ffa631c4bff59dde59b598011f570e27dfba3515/e71f6a3a1d5c826a30384fec587ca7503ef6bde5/47178c7722ac528ea08aa82c3ef9ffa178962d7a is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.16.0
• 5.16.1
• 5.16.2
• 5.16.3
• 5.16.4
• 5.16.5
• 5.16.6
• 5.16.7
• 5.16.8
• 5.16.9
• 5.16.10
• 5.16.11
• 5.16.12
• 5.16.13
• 5.16.14
• 5.16.15
• 5.16.16
• 5.16.17
• 5.16.18
• 5.17.0
• 5.17.1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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Entryinfo

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