CVE-2024-46796

In the Linux kernel, the following vulnerability has been resolved:

smb: client: fix double put of @cfile in smb2_set_path_size()

If smb2_compound_op() is called with a valid @cfile and returned

-EINVAL, we need to call cifs_get_writable_path() before retrying it

as the reference of @cfile was already dropped by previous call.

This fixes the following KASAN splat when running fstests generic/013

against Windows Server 2022:

CIFS: Attempting to mount //w22-fs0/scratch

run fstests generic/013 at 2024-09-02 19:48:59

==================================================================

BUG: KASAN: slab-use-after-free in detach_if_pending+0xab/0x200

Write of size 8 at addr ffff88811f1a3730 by task kworker/3:2/176

CPU: 3 UID: 0 PID: 176 Comm: kworker/3:2 Not tainted 6.11.0-rc6 #2

Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40

04/01/2014

Workqueue: cifsoplockd cifs_oplock_break [cifs]

Call Trace:

<TASK>

dump_stack_lvl+0x5d/0x80

? detach_if_pending+0xab/0x200

print_report+0x156/0x4d9

? detach_if_pending+0xab/0x200

? __virt_addr_valid+0x145/0x300

? __phys_addr+0x46/0x90

? detach_if_pending+0xab/0x200

kasan_report+0xda/0x110

? detach_if_pending+0xab/0x200

detach_if_pending+0xab/0x200

timer_delete+0x96/0xe0

? __pfx_timer_delete+0x10/0x10

? rcu_is_watching+0x20/0x50

try_to_grab_pending+0x46/0x3b0

__cancel_work+0x89/0x1b0

? __pfx___cancel_work+0x10/0x10

? kasan_save_track+0x14/0x30

cifs_close_deferred_file+0x110/0x2c0 [cifs]

? __pfx_cifs_close_deferred_file+0x10/0x10 [cifs]

? __pfx_down_read+0x10/0x10

cifs_oplock_break+0x4c1/0xa50 [cifs]

? __pfx_cifs_oplock_break+0x10/0x10 [cifs]

? lock_is_held_type+0x85/0xf0

? mark_held_locks+0x1a/0x90

process_one_work+0x4c6/0x9f0

? find_held_lock+0x8a/0xa0

? __pfx_process_one_work+0x10/0x10

? lock_acquired+0x220/0x550

? __list_add_valid_or_report+0x37/0x100

worker_thread+0x2e4/0x570

? __kthread_parkme+0xd1/0xf0

? __pfx_worker_thread+0x10/0x10

kthread+0x17f/0x1c0

? kthread+0xda/0x1c0

? __pfx_kthread+0x10/0x10

ret_from_fork+0x31/0x60

? __pfx_kthread+0x10/0x10

ret_from_fork_asm+0x1a/0x30

</TASK>

Allocated by task 1118:

kasan_save_stack+0x30/0x50

kasan_save_track+0x14/0x30

__kasan_kmalloc+0xaa/0xb0

cifs_new_fileinfo+0xc8/0x9d0 [cifs]

cifs_atomic_open+0x467/0x770 [cifs]

lookup_open.isra.0+0x665/0x8b0

path_openat+0x4c3/0x1380

do_filp_open+0x167/0x270

do_sys_openat2+0x129/0x160

__x64_sys_creat+0xad/0xe0

do_syscall_64+0xbb/0x1d0

entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 83:

kasan_save_stack+0x30/0x50

kasan_save_track+0x14/0x30

kasan_save_free_info+0x3b/0x70

poison_slab_object+0xe9/0x160

__kasan_slab_free+0x32/0x50

kfree+0xf2/0x300

process_one_work+0x4c6/0x9f0

worker_thread+0x2e4/0x570

kthread+0x17f/0x1c0

ret_from_fork+0x31/0x60

ret_from_fork_asm+0x1a/0x30

Last potentially related work creation:

kasan_save_stack+0x30/0x50

__kasan_record_aux_stack+0xad/0xc0

insert_work+0x29/0xe0

__queue_work+0x5ea/0x760

queue_work_on+0x6d/0x90

_cifsFileInfo_put+0x3f6/0x770 [cifs]

smb2_compound_op+0x911/0x3940 [cifs]

smb2_set_path_size+0x228/0x270 [cifs]

cifs_set_file_size+0x197/0x460 [cifs]

cifs_setattr+0xd9c/0x14b0 [cifs]

notify_change+0x4e3/0x740

do_truncate+0xfa/0x180

vfs_truncate+0x195/0x200

__x64_sys_truncate+0x109/0x150

do_syscall_64+0xbb/0x1d0

entry_SYSCALL_64_after_hwframe+0x77/0x7f