CVE-2022-49281

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