CIFS: VFS: Use of the less secure dialect vers=1.0 is not recommended unless required for access to very old servers
CIFS: Attempting to mount \\127.0.0.1\share
==================================================================
BUG: KASAN: use-after-free in cifs_fscache_release_client_cookie+0xa0/0x160 fs/cifs/fscache.c:81
Write of size 8 at addr ffff888079714580 by task syz.3.190/5151

CPU: 0 PID: 5151 Comm: syz.3.190 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 cifs_fscache_release_client_cookie+0xa0/0x160 fs/cifs/fscache.c:81
 cifs_put_tcp_session+0x25f/0x3d0 fs/cifs/connect.c:1399
 mount_put_conns+0xb0/0x270 fs/cifs/connect.c:2969
 cifs_mount+0xbf5/0x1380 fs/cifs/connect.c:3597
 cifs_smb3_do_mount+0x366/0x760 fs/cifs/cifsfs.c:895
 smb3_get_tree_common fs/cifs/fs_context.c:708 [inline]
 smb3_get_tree+0x59a/0xa80 fs/cifs/fs_context.c:726
 vfs_get_tree+0x88/0x270 fs/super.c:1541
 do_new_mount+0x247/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f32988e5159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3296b1c028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3298b6d090 RCX: 00007f32988e5159
RDX: 0000200000000400 RSI: 0000200000000200 RDI: 0000200000000300
RBP: 00007f329897c06b R08: 0000200000000500 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3298b6d128 R14: 00007f3298b6d090 R15: 00007fff2f220af8
 </TASK>

Allocated by task 5151:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc+0xaf/0xe0 mm/kasan/common.c:522
 kmalloc include/linux/slab.h:607 [inline]
 kzalloc include/linux/slab.h:738 [inline]
 cifs_get_tcp_session+0xac/0x18f0 fs/cifs/connect.c:1425
 mount_get_conns+0xc3/0xe00 fs/cifs/connect.c:2988
 is_dfs_mount fs/cifs/connect.c:3354 [inline]
 cifs_mount+0x162/0x1380 fs/cifs/connect.c:3549
 cifs_smb3_do_mount+0x366/0x760 fs/cifs/cifsfs.c:895
 smb3_get_tree_common fs/cifs/fs_context.c:708 [inline]
 smb3_get_tree+0x59a/0xa80 fs/cifs/fs_context.c:726
 vfs_get_tree+0x88/0x270 fs/super.c:1541
 do_new_mount+0x247/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 5152:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1710 [inline]
 slab_free_freelist_hook+0xec/0x170 mm/slub.c:1736
 slab_free mm/slub.c:3504 [inline]
 kfree+0xef/0x2a0 mm/slub.c:4564
 clean_demultiplex_info fs/cifs/connect.c:846 [inline]
 cifs_demultiplex_thread+0x308c/0x35b0 fs/cifs/connect.c:1134
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

The buggy address belongs to the object at ffff888079714000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1408 bytes inside of
 4096-byte region [ffff888079714000, ffff888079715000)
The buggy address belongs to the page:
page:ffffea0001e5c400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x79710
head:ffffea0001e5c400 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888016c42140
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4189, ts 165862777935, free_ts 165600929230
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x24f6/0x2670 mm/page_alloc.c:4192
 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501
 alloc_slab_page mm/slub.c:1780 [inline]
 allocate_slab mm/slub.c:1917 [inline]
 new_slab+0xc0/0x4b0 mm/slub.c:1980
 ___slab_alloc+0x807/0xdd0 mm/slub.c:3013
 __slab_alloc mm/slub.c:3100 [inline]
 slab_alloc_node mm/slub.c:3191 [inline]
 __kmalloc_node_track_caller+0x13d/0x3a0 mm/slub.c:4963
 kmalloc_reserve net/core/skbuff.c:356 [inline]
 __alloc_skb+0x22c/0x750 net/core/skbuff.c:427
 alloc_skb include/linux/skbuff.h:1162 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:664 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:721 [inline]
 nsim_dev_trap_report_work+0x25c/0xab0 drivers/net/netdevsim/dev.c:762
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396
 free_slab mm/slub.c:2020 [inline]
 discard_slab mm/slub.c:2026 [inline]
 __unfreeze_partials+0x188/0x1e0 mm/slub.c:2512
 put_cpu_partial+0x12d/0x190 mm/slub.c:2592
 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3225 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc+0x15d/0x280 mm/slub.c:3238
 kmem_cache_zalloc include/linux/slab.h:728 [inline]
 jbd2_alloc_handle include/linux/jbd2.h:1597 [inline]
 new_handle fs/jbd2/transaction.c:477 [inline]
 jbd2__journal_start+0x13c/0x5a0 fs/jbd2/transaction.c:504
 __ext4_journal_start_sb+0x167/0x360 fs/ext4/ext4_jbd2.c:105
 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
 ext4_dirty_inode+0x8b/0x100 fs/ext4/inode.c:6084
 __mark_inode_dirty+0x2c8/0xc90 fs/fs-writeback.c:2480
 generic_update_time+0x1cd/0x1f0 fs/inode.c:1881
 inode_update_time fs/inode.c:1894 [inline]
 file_update_time+0x3c0/0x440 fs/inode.c:2083
 ext4_page_mkwrite+0x1bc/0x1250 fs/ext4/inode.c:6205

Memory state around the buggy address:
 ffff888079714480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888079714500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888079714580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888079714600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888079714680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================