[syzbot] [v9fs?] KASAN: slab-use-after-free Read in p9_fd_request

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1b294a1f3561 Merge tag 'net-next-6.10' of git://git.kernel..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1507ead0980000
kernel config: https://syzkaller.appspot.com/x/.config?x=bddb81daac38d475
dashboard link: https://syzkaller.appspot.com/bug?extid=4e2269434184f95684d6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6cf1ddff37cc/disk-1b294a1f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/85de01f27485/vmlinux-1b294a1f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/cc17337dab81/bzImage-1b294a1f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4e2269...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: slab-use-after-free in __lock_acquire+0x78/0x1fd0 kernel/locking/lockdep.c:5005
Read of size 8 at addr ffff888079d8f848 by task kworker/u8:15/9021

CPU: 1 PID: 9021 Comm: kworker/u8:15 Not tainted 6.9.0-syzkaller-05151-g1b294a1f3561 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: events_unbound netfs_write_collection_worker
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
__lock_acquire+0x78/0x1fd0 kernel/locking/lockdep.c:5005
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
p9_fd_request+0x53/0x520 net/9p/trans_fd.c:674
p9_client_rpc+0x305/0xac0 net/9p/client.c:704
p9_client_clunk+0x75/0x260 net/9p/client.c:1439
netfs_free_request+0x246/0x5e0 fs/netfs/objects.c:133
netfs_write_collection_worker+0x507c/0x5640 fs/netfs/write_collect.c:701
process_one_work kernel/workqueue.c:3267 [inline]
process_scheduled_works+0xa12/0x17c0 kernel/workqueue.c:3348
worker_thread+0x86d/0xd70 kernel/workqueue.c:3429
kthread+0x2f2/0x390 kernel/kthread.c:389
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>

Allocated by task 14624:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
__kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
kasan_kmalloc include/linux/kasan.h:211 [inline]
kmalloc_trace+0x1db/0x370 mm/slub.c:4070
kmalloc include/linux/slab.h:628 [inline]
kzalloc include/linux/slab.h:749 [inline]
p9_fd_open net/9p/trans_fd.c:828 [inline]
p9_fd_create+0x17b/0x530 net/9p/trans_fd.c:1102
p9_client_create+0x862/0x1040 net/9p/client.c:1013
v9fs_session_init+0x1e4/0x1b80 fs/9p/v9fs.c:410
v9fs_mount+0xce/0xa90 fs/9p/vfs_super.c:122
legacy_get_tree+0xf0/0x190 fs/fs_context.c:662
vfs_get_tree+0x92/0x2a0 fs/super.c:1779
do_new_mount+0x2be/0xb40 fs/namespace.c:3352
do_mount fs/namespace.c:3692 [inline]
__do_sys_mount fs/namespace.c:3898 [inline]
__se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3875
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 14191:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240
__kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
kasan_slab_free include/linux/kasan.h:184 [inline]
slab_free_hook mm/slub.c:2121 [inline]
slab_free mm/slub.c:4353 [inline]
kfree+0x153/0x3b0 mm/slub.c:4463
p9_client_destroy+0xc9/0x660 net/9p/client.c:1065
v9fs_session_close+0x51/0x210 fs/9p/v9fs.c:506
v9fs_kill_super+0x5c/0x90 fs/9p/vfs_super.c:196
deactivate_locked_super+0xc6/0x130 fs/super.c:472
cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267
task_work_run+0x251/0x310 kernel/task_work.c:180
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218
do_syscall_64+0x102/0x240 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Last potentially related work creation:
kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
__kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541
insert_work+0x3e/0x330 kernel/workqueue.c:2261
__queue_work+0xc24/0xef0 kernel/workqueue.c:2413
queue_work_on+0x14f/0x250 kernel/workqueue.c:2448
queue_work include/linux/workqueue.h:605 [inline]
schedule_work include/linux/workqueue.h:666 [inline]
p9_poll_mux net/9p/trans_fd.c:639 [inline]
p9_poll_workfn+0x3b0/0x5e0 net/9p/trans_fd.c:1177
process_one_work kernel/workqueue.c:3267 [inline]
process_scheduled_works+0xa12/0x17c0 kernel/workqueue.c:3348
worker_thread+0x86d/0xd70 kernel/workqueue.c:3429
kthread+0x2f2/0x390 kernel/kthread.c:389
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Second to last potentially related work creation:
kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
__kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541
insert_work+0x3e/0x330 kernel/workqueue.c:2261
__queue_work+0xc24/0xef0 kernel/workqueue.c:2413
queue_work_on+0x14f/0x250 kernel/workqueue.c:2448
queue_work include/linux/workqueue.h:605 [inline]
schedule_work include/linux/workqueue.h:666 [inline]
p9_fd_request+0x2e1/0x520 net/9p/trans_fd.c:691
p9_client_rpc+0x305/0xac0 net/9p/client.c:704
p9_client_write+0x328/0x7a0 net/9p/client.c:1633
v9fs_issue_write+0xfd/0x1c0 fs/9p/vfs_addr.c:59
netfs_issue_write fs/netfs/write_issue.c:258 [inline]
netfs_advance_write+0x776/0xe00 fs/netfs/write_issue.c:298
netfs_write_folio+0x1263/0x1f70 fs/netfs/write_issue.c:468
netfs_writepages+0x91f/0xf20 fs/netfs/write_issue.c:536
do_writepages+0x35b/0x870 mm/page-writeback.c:2613
filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:397
__filemap_fdatawrite_range mm/filemap.c:430 [inline]
__filemap_fdatawrite mm/filemap.c:436 [inline]
filemap_fdatawrite+0xfb/0x160 mm/filemap.c:441
v9fs_dir_release+0x154/0x560 fs/9p/vfs_dir.c:219
__fput+0x42b/0x8a0 fs/file_table.c:422
__do_sys_close fs/open.c:1556 [inline]
__se_sys_close fs/open.c:1541 [inline]
__x64_sys_close+0x7f/0x110 fs/open.c:1541
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888079d8f800
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 72 bytes inside of
freed 1024-byte region [ffff888079d8f800, ffff888079d8fc00)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888079d8c800 pfn:0x79d88
head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000a40(workingset|slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000a40 ffff888015041dc0 ffffea0000471810 ffffea0000aef810
raw: ffff888079d8c800 000000000010000f 00000001ffffffff 0000000000000000
head: 00fff00000000a40 ffff888015041dc0 ffffea0000471810 ffffea0000aef810
head: ffff888079d8c800 000000000010000f 00000001ffffffff 0000000000000000
head: 00fff00000000003 ffffea0001e76201 dead000000000122 00000000ffffffff
head: 0000000800000000 0000000000000000 00000000ffffffff 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 0x152820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 62, tgid 62 (kworker/u8:4), ts 255477095338, free_ts 255425419447
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534
prep_new_page mm/page_alloc.c:1541 [inline]
get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317
__alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page+0x5f/0x160 mm/slub.c:2190
allocate_slab mm/slub.c:2353 [inline]
new_slab+0x84/0x2f0 mm/slub.c:2406
___slab_alloc+0xb07/0x12e0 mm/slub.c:3592
__slab_alloc mm/slub.c:3682 [inline]
__slab_alloc_node mm/slub.c:3735 [inline]
slab_alloc_node mm/slub.c:3908 [inline]
__do_kmalloc_node mm/slub.c:4038 [inline]
__kmalloc+0x2e5/0x4a0 mm/slub.c:4052
kmalloc include/linux/slab.h:632 [inline]
kzalloc include/linux/slab.h:749 [inline]
ieee802_11_parse_elems_full+0xd5/0x2870 net/mac80211/parse.c:880
ieee802_11_parse_elems_crc net/mac80211/ieee80211_i.h:2330 [inline]
ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2337 [inline]
ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1574 [inline]
ieee80211_ibss_rx_queued_mgmt+0x4c8/0x2d70 net/mac80211/ibss.c:1605
ieee80211_iface_process_skb net/mac80211/iface.c:1605 [inline]
ieee80211_iface_work+0x8a3/0xf10 net/mac80211/iface.c:1659
cfg80211_wiphy_work+0x223/0x260 net/wireless/core.c:437
process_one_work kernel/workqueue.c:3267 [inline]
process_scheduled_works+0xa12/0x17c0 kernel/workqueue.c:3348
worker_thread+0x86d/0xd70 kernel/workqueue.c:3429
kthread+0x2f2/0x390 kernel/kthread.c:389
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
page last free pid 7787 tgid 7785 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1141 [inline]
free_unref_page_prepare+0x986/0xab0 mm/page_alloc.c:2347
free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487
__folio_put_large+0x168/0x1d0 mm/swap.c:132
__folio_put+0x299/0x390 mm/swap.c:140
page_to_skb+0x3dd/0x9b0 drivers/net/virtio_net.c:810
receive_mergeable drivers/net/virtio_net.c:1834 [inline]
receive_buf+0x3bd/0x3830 drivers/net/virtio_net.c:1955
virtnet_receive drivers/net/virtio_net.c:2259 [inline]
virtnet_poll+0x7f8/0x18c0 drivers/net/virtio_net.c:2362
__napi_poll+0xcd/0x490 net/core/dev.c:6721
napi_poll net/core/dev.c:6790 [inline]
net_rx_action+0x7bb/0x10a0 net/core/dev.c:6906
handle_softirqs+0x2d8/0x990 kernel/softirq.c:554
__do_softirq kernel/softirq.c:588 [inline]
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
common_interrupt+0xaa/0xd0 arch/x86/kernel/irq.c:278
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693

Memory state around the buggy address:
ffff888079d8f700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888079d8f780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888079d8f800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888079d8f880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888079d8f900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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[asma...@codewreck.org]

syzbot wrote on Thu, May 23, 2024 at 11:35:28AM -0700:
> syzbot found the following issue on:
>
> HEAD commit: 1b294a1f3561 Merge tag 'net-next-6.10' of git://git.kernel..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=1507ead0980000
> kernel config: https://syzkaller.appspot.com/x/.config?x=bddb81daac38d475
> dashboard link: https://syzkaller.appspot.com/bug?extid=4e2269434184f95684d6
> compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Looks like another duplicate of the same destroy vs netfs issue, marking
as dup (or trying to at least)

#syz dup: [syzbot] [v9fs?] KASAN: slab-use-after-free Read in p9_client_destroy

--
Dominique Martinet | Asmadeus