[syzbot] KASAN: use-after-free Read in ath9k_hif_usb_reg_in_cb (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 993a44fa85c1 usb: gadget: f_uac2: allow changing interface..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
console output: https://syzkaller.appspot.com/x/log.txt?x=149215e4700000
kernel config: https://syzkaller.appspot.com/x/.config?x=7d7c811a1a4d0135
dashboard link: https://syzkaller.appspot.com/bug?extid=b05dabaed0b1f0b0a5e4
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b05dab...@syzkaller.appspotmail.com

usb 1-1: ath: unknown panic pattern!
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:147 [inline]
BUG: KASAN: use-after-free in skb_unref include/linux/skbuff.h:1098 [inline]
BUG: KASAN: use-after-free in kfree_skb_reason+0x33/0x400 net/core/skbuff.c:772
Read of size 4 at addr ffff88810feac35c by task swapper/0/0

CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.17.0-rc1-syzkaller-00028-g993a44fa85c1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255
__kasan_report mm/kasan/report.c:442 [inline]
kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:71 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
refcount_read include/linux/refcount.h:147 [inline]
skb_unref include/linux/skbuff.h:1098 [inline]
kfree_skb_reason+0x33/0x400 net/core/skbuff.c:772
kfree_skb include/linux/skbuff.h:1114 [inline]
ath9k_hif_usb_reg_in_cb+0x4c2/0x630 drivers/net/wireless/ath/ath9k/hif_usb.c:771
__usb_hcd_giveback_urb+0x2b0/0x5c0 drivers/usb/core/hcd.c:1663
usb_hcd_giveback_urb+0x367/0x410 drivers/usb/core/hcd.c:1733
dummy_timer+0x11f9/0x32b0 drivers/usb/gadget/udc/dummy_hcd.c:1987
call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
expire_timers kernel/time/timer.c:1466 [inline]
__run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734
__run_timers kernel/time/timer.c:1715 [inline]
run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
__do_softirq+0x288/0x9a5 kernel/softirq.c:558
invoke_softirq kernel/softirq.c:432 [inline]
__irq_exit_rcu+0x113/0x170 kernel/softirq.c:637
irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline]
RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
RIP: 0010:acpi_idle_do_entry+0x1c6/0x250 drivers/acpi/processor_idle.c:551
Code: 89 de e8 6d 8c 6e fb 84 db 75 ac e8 84 88 6e fb e8 af c3 74 fb eb 0c e8 78 88 6e fb 0f 00 2d 91 1f 75 00 e8 6c 88 6e fb fb f4 <9c> 5b 81 e3 00 02 00 00 fa 31 ff 48 89 de e8 e7 8a 6e fb 48 85 db
RSP: 0018:ffffffff87607d60 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffffffff87652680 RSI: ffffffff85d51c94 RDI: 0000000000000000
RBP: ffff888100378864 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff8149e068 R11: 0000000000000000 R12: 0000000000000001
R13: ffff888100378800 R14: ffff888100378864 R15: ffff88810a1b3004
acpi_idle_enter+0x361/0x500 drivers/acpi/processor_idle.c:687
cpuidle_enter_state+0x1b1/0xc80 drivers/cpuidle/cpuidle.c:237
cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:351
call_cpuidle kernel/sched/idle.c:158 [inline]
cpuidle_idle_call kernel/sched/idle.c:239 [inline]
do_idle+0x3e8/0x590 kernel/sched/idle.c:306
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
start_kernel+0x47a/0x49b init/main.c:1138
secondary_startup_64_no_verify+0xc3/0xcb
</TASK>

Allocated by task 11515:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:45 [inline]
set_alloc_info mm/kasan/common.c:436 [inline]
__kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:469
kasan_slab_alloc include/linux/kasan.h:260 [inline]
slab_post_alloc_hook mm/slab.h:732 [inline]
slab_alloc_node mm/slub.c:3230 [inline]
kmem_cache_alloc_node+0x25e/0x4b0 mm/slub.c:3266
__alloc_skb+0x215/0x340 net/core/skbuff.c:414
alloc_skb include/linux/skbuff.h:1158 [inline]
ath9k_hif_usb_alloc_reg_in_urbs drivers/net/wireless/ath/ath9k/hif_usb.c:964 [inline]
ath9k_hif_usb_alloc_urbs+0x91d/0x1040 drivers/net/wireless/ath/ath9k/hif_usb.c:1023
ath9k_hif_usb_dev_init drivers/net/wireless/ath/ath9k/hif_usb.c:1109 [inline]
ath9k_hif_usb_firmware_cb+0x148/0x530 drivers/net/wireless/ath/ath9k/hif_usb.c:1242
request_firmware_work_func+0x12c/0x230 drivers/base/firmware_loader/main.c:1022
process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
worker_thread+0x657/0x1110 kernel/workqueue.c:2454
kthread+0x2ef/0x3a0 kernel/kthread.c:377
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 0:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track+0x21/0x30 mm/kasan/common.c:45
kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
____kasan_slab_free mm/kasan/common.c:366 [inline]
____kasan_slab_free mm/kasan/common.c:328 [inline]
__kasan_slab_free+0xfa/0x130 mm/kasan/common.c:374
kasan_slab_free include/linux/kasan.h:236 [inline]
slab_free_hook mm/slub.c:1728 [inline]
slab_free_freelist_hook mm/slub.c:1754 [inline]
slab_free mm/slub.c:3509 [inline]
kmem_cache_free+0xd7/0x3c0 mm/slub.c:3526
kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:700
__kfree_skb net/core/skbuff.c:757 [inline]
kfree_skb_reason net/core/skbuff.c:776 [inline]
kfree_skb_reason+0x145/0x400 net/core/skbuff.c:770
kfree_skb include/linux/skbuff.h:1114 [inline]
ath9k_htc_rx_msg+0x1ed/0xb70 drivers/net/wireless/ath/ath9k/htc_hst.c:451
ath9k_hif_usb_reg_in_cb+0x1ac/0x630 drivers/net/wireless/ath/ath9k/hif_usb.c:740
__usb_hcd_giveback_urb+0x2b0/0x5c0 drivers/usb/core/hcd.c:1663
usb_hcd_giveback_urb+0x367/0x410 drivers/usb/core/hcd.c:1733
dummy_timer+0x11f9/0x32b0 drivers/usb/gadget/udc/dummy_hcd.c:1987
call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
expire_timers kernel/time/timer.c:1466 [inline]
__run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734
__run_timers kernel/time/timer.c:1715 [inline]
run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
__do_softirq+0x288/0x9a5 kernel/softirq.c:558

The buggy address belongs to the object at ffff88810feac280
which belongs to the cache skbuff_head_cache of size 232
The buggy address is located 220 bytes inside of
232-byte region [ffff88810feac280, ffff88810feac368)
The buggy address belongs to the page:
page:ffffea00043fab00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10feac
flags: 0x200000000000200(slab|node=0|zone=2)
raw: 0200000000000200 ffffea00044de700 dead000000000003 ffff8881003d3640
raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 1269, ts 548051559679, free_ts 548051333117
prep_new_page mm/page_alloc.c:2434 [inline]
get_page_from_freelist+0x122d/0x2940 mm/page_alloc.c:4165
__alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389
alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271
alloc_slab_page mm/slub.c:1799 [inline]
allocate_slab mm/slub.c:1944 [inline]
new_slab+0x28a/0x3b0 mm/slub.c:2004
___slab_alloc+0x81a/0xe60 mm/slub.c:3018
__slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105
slab_alloc_node mm/slub.c:3196 [inline]
slab_alloc mm/slub.c:3238 [inline]
kmem_cache_alloc+0x3bb/0x480 mm/slub.c:3243
skb_clone+0x170/0x3c0 net/core/skbuff.c:1519
dev_queue_xmit_nit+0x38c/0xa90 net/core/dev.c:2211
xmit_one net/core/dev.c:3468 [inline]
dev_hard_start_xmit+0xad/0x920 net/core/dev.c:3489
sch_direct_xmit+0x25b/0x7a0 net/sched/sch_generic.c:342
__dev_xmit_skb net/core/dev.c:3700 [inline]
__dev_queue_xmit+0x11b0/0x3200 net/core/dev.c:4081
neigh_hh_output include/net/neighbour.h:525 [inline]
neigh_output include/net/neighbour.h:539 [inline]
ip_finish_output2+0x143f/0x20c0 net/ipv4/ip_output.c:221
__ip_finish_output.part.0+0x1b7/0x350 net/ipv4/ip_output.c:299
__ip_finish_output net/ipv4/ip_output.c:287 [inline]
ip_finish_output net/ipv4/ip_output.c:309 [inline]
NF_HOOK_COND include/linux/netfilter.h:296 [inline]
ip_output+0x2ed/0x5f0 net/ipv4/ip_output.c:423
dst_output include/net/dst.h:451 [inline]
ip_local_out net/ipv4/ip_output.c:126 [inline]
__ip_queue_xmit+0x984/0x1b80 net/ipv4/ip_output.c:525
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1352 [inline]
free_pcp_prepare+0x361/0x760 mm/page_alloc.c:1404
free_unref_page_prepare mm/page_alloc.c:3325 [inline]
free_unref_page+0x19/0x580 mm/page_alloc.c:3404
__put_single_page mm/swap.c:99 [inline]
__put_page+0x103/0x140 mm/swap.c:130
folio_put include/linux/mm.h:1199 [inline]
put_page include/linux/mm.h:1237 [inline]
anon_pipe_buf_release+0x1d9/0x280 fs/pipe.c:138
pipe_buf_release include/linux/pipe_fs_i.h:203 [inline]
pipe_read+0x6e4/0x11b0 fs/pipe.c:323
call_read_iter include/linux/fs.h:2068 [inline]
new_sync_read+0x5c2/0x6e0 fs/read_write.c:400
vfs_read+0x35c/0x600 fs/read_write.c:481
ksys_read+0x1ee/0x250 fs/read_write.c:619
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

Memory state around the buggy address:
ffff88810feac200: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
ffff88810feac280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88810feac300: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
^
ffff88810feac380: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
ffff88810feac400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 89 de mov %ebx,%esi
2: e8 6d 8c 6e fb callq 0xfb6e8c74
7: 84 db test %bl,%bl
9: 75 ac jne 0xffffffb7
b: e8 84 88 6e fb callq 0xfb6e8894
10: e8 af c3 74 fb callq 0xfb74c3c4
15: eb 0c jmp 0x23
17: e8 78 88 6e fb callq 0xfb6e8894
1c: 0f 00 2d 91 1f 75 00 verw 0x751f91(%rip) # 0x751fb4
23: e8 6c 88 6e fb callq 0xfb6e8894
28: fb sti
29: f4 hlt
* 2a: 9c pushfq <-- trapping instruction
2b: 5b pop %rbx
2c: 81 e3 00 02 00 00 and $0x200,%ebx
32: fa cli
33: 31 ff xor %edi,%edi
35: 48 89 de mov %rbx,%rsi
38: e8 e7 8a 6e fb callq 0xfb6e8b24
3d: 48 85 db test %rbx,%rbx


---
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See https://goo.gl/tpsmEJ for more information about syzbot.
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syzbot will keep track of this issue. See:
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 4378e427f705 usbip: vudc: Make use of the helper macro LIS..

git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing

console output: https://syzkaller.appspot.com/x/log.txt?x=1565305a700000
kernel config: https://syzkaller.appspot.com/x/.config?x=83e40899a8923e35

dashboard link: https://syzkaller.appspot.com/bug?extid=b05dabaed0b1f0b0a5e4
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13a352f2700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=162e878c700000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b05dab...@syzkaller.appspotmail.com

usb 1-1: ath: unknown panic pattern!
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:147 [inline]
BUG: KASAN: use-after-free in skb_unref include/linux/skbuff.h:1098 [inline]
BUG: KASAN: use-after-free in kfree_skb_reason+0x33/0x400 net/core/skbuff.c:772

Read of size 4 at addr ffff888118b6be9c by task syz-executor056/1278

CPU: 1 PID: 1278 Comm: syz-executor056 Not tainted 5.17.0-rc4-syzkaller-00061-g4378e427f705 #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:

<TASK>

__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255
__kasan_report mm/kasan/report.c:442 [inline]
kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189
instrument_atomic_read include/linux/instrumented.h:71 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
refcount_read include/linux/refcount.h:147 [inline]
skb_unref include/linux/skbuff.h:1098 [inline]
kfree_skb_reason+0x33/0x400 net/core/skbuff.c:772
kfree_skb include/linux/skbuff.h:1114 [inline]
ath9k_hif_usb_reg_in_cb+0x4c2/0x630 drivers/net/wireless/ath/ath9k/hif_usb.c:771

__usb_hcd_giveback_urb+0x2b0/0x5c0 drivers/usb/core/hcd.c:1670
usb_hcd_giveback_urb+0x367/0x410 drivers/usb/core/hcd.c:1747

dummy_timer+0x11f9/0x32b0 drivers/usb/gadget/udc/dummy_hcd.c:1987
call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
expire_timers kernel/time/timer.c:1466 [inline]
__run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734
__run_timers kernel/time/timer.c:1715 [inline]
run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
__do_softirq+0x288/0x9a5 kernel/softirq.c:558
invoke_softirq kernel/softirq.c:432 [inline]
__irq_exit_rcu+0x113/0x170 kernel/softirq.c:637
irq_exit_rcu+0x5/0x20 kernel/softirq.c:649

sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1097
asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0033:0x7f65f5afb6ca
Code: 83 ff 03 74 3b 48 83 ec 28 b8 fa ff ff ff 83 ff 02 49 89 ca 0f 44 f8 64 8b 04 25 18 00 00 00 85 c0 75 2d b8 e6 00 00 00 0f 05 <89> c2 f7 da 3d 00 f0 ff ff b8 00 00 00 00 0f 47 c2 48 83 c4 28 c3
RSP: 002b:00007ffd489cd250 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 000000000002e7e7 RCX: 00007f65f5afb6ca
RDX: 00007ffd489cd290 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000008 R08: 00000000000000c0 R09: 00007ffd489f0080
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd489cd2e0
R13: 00007ffd489cd340 R14: 0000000000000002 R15: 431bde82d7b634db
</TASK>

Allocated by task 69:

kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:45 [inline]
set_alloc_info mm/kasan/common.c:436 [inline]
__kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:469
kasan_slab_alloc include/linux/kasan.h:260 [inline]
slab_post_alloc_hook mm/slab.h:732 [inline]
slab_alloc_node mm/slub.c:3230 [inline]
kmem_cache_alloc_node+0x25e/0x4b0 mm/slub.c:3266
__alloc_skb+0x215/0x340 net/core/skbuff.c:414
alloc_skb include/linux/skbuff.h:1158 [inline]
ath9k_hif_usb_alloc_reg_in_urbs drivers/net/wireless/ath/ath9k/hif_usb.c:964 [inline]
ath9k_hif_usb_alloc_urbs+0x91d/0x1040 drivers/net/wireless/ath/ath9k/hif_usb.c:1023
ath9k_hif_usb_dev_init drivers/net/wireless/ath/ath9k/hif_usb.c:1109 [inline]
ath9k_hif_usb_firmware_cb+0x148/0x530 drivers/net/wireless/ath/ath9k/hif_usb.c:1242
request_firmware_work_func+0x12c/0x230 drivers/base/firmware_loader/main.c:1022
process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
worker_thread+0x657/0x1110 kernel/workqueue.c:2454
kthread+0x2ef/0x3a0 kernel/kthread.c:377
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 1278:

kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track+0x21/0x30 mm/kasan/common.c:45
kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
____kasan_slab_free mm/kasan/common.c:366 [inline]

____kasan_slab_free+0x102/0x150 mm/kasan/common.c:328

kasan_slab_free include/linux/kasan.h:236 [inline]
slab_free_hook mm/slub.c:1728 [inline]
slab_free_freelist_hook mm/slub.c:1754 [inline]
slab_free mm/slub.c:3509 [inline]

kmem_cache_free+0xd5/0x400 mm/slub.c:3526

kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:700
__kfree_skb net/core/skbuff.c:757 [inline]
kfree_skb_reason net/core/skbuff.c:776 [inline]
kfree_skb_reason+0x145/0x400 net/core/skbuff.c:770
kfree_skb include/linux/skbuff.h:1114 [inline]
ath9k_htc_rx_msg+0x1ed/0xb70 drivers/net/wireless/ath/ath9k/htc_hst.c:451
ath9k_hif_usb_reg_in_cb+0x1ac/0x630 drivers/net/wireless/ath/ath9k/hif_usb.c:740

__usb_hcd_giveback_urb+0x2b0/0x5c0 drivers/usb/core/hcd.c:1670
usb_hcd_giveback_urb+0x367/0x410 drivers/usb/core/hcd.c:1747

dummy_timer+0x11f9/0x32b0 drivers/usb/gadget/udc/dummy_hcd.c:1987
call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
expire_timers kernel/time/timer.c:1466 [inline]
__run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734
__run_timers kernel/time/timer.c:1715 [inline]
run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
__do_softirq+0x288/0x9a5 kernel/softirq.c:558

The buggy address belongs to the object at ffff888118b6bdc0

which belongs to the cache skbuff_head_cache of size 232
The buggy address is located 220 bytes inside of

232-byte region [ffff888118b6bdc0, ffff888118b6bea8)

The buggy address belongs to the page:

page:ffffea000462dac0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x118b6b
flags: 0x200000000000200(slab|node=0|zone=2)
raw: 0200000000000200 0000000000000000 dead000000000001 ffff8881003d3640

raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated

page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1170, ts 8677100351, free_ts 0

prep_new_page mm/page_alloc.c:2434 [inline]
get_page_from_freelist+0x122d/0x2940 mm/page_alloc.c:4165
__alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389
alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271
alloc_slab_page mm/slub.c:1799 [inline]

allocate_slab+0x27f/0x3e0 mm/slub.c:1944
new_slab mm/slub.c:2004 [inline]
___slab_alloc+0xc12/0x1450 mm/slub.c:3018

__slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105
slab_alloc_node mm/slub.c:3196 [inline]

kmem_cache_alloc_node+0x397/0x4b0 mm/slub.c:3266

__alloc_skb+0x215/0x340 net/core/skbuff.c:414
alloc_skb include/linux/skbuff.h:1158 [inline]

alloc_uevent_skb+0x7b/0x210 lib/kobject_uevent.c:290
uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline]
kobject_uevent_net_broadcast lib/kobject_uevent.c:409 [inline]
kobject_uevent_env+0xadf/0x1600 lib/kobject_uevent.c:593
kobject_synth_uevent+0x701/0x850 lib/kobject_uevent.c:208
store_uevent+0x12/0x20 kernel/module.c:1166
module_attr_store+0x50/0x80 kernel/params.c:919
sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:136
kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:296
call_write_iter include/linux/fs.h:2074 [inline]
new_sync_write+0x431/0x660 fs/read_write.c:503
page_owner free stack trace missing

Memory state around the buggy address:

ffff888118b6bd80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
ffff888118b6be00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888118b6be80: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
^
ffff888118b6bf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888118b6bf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

[syzbot]

syzbot suspects this issue was fixed by commit:

commit 09c5ba0aa2fcfdadb17d045c3ee6f86d69270df7
Author: John Ogness <john....@linutronix.de>
Date: Thu Apr 21 21:22:48 2022 +0000

printk: add kthread console printers

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10e88490080000
start commit: 210e04ff7681 Merge tag 'pci-v5.18-fixes-1' of git://git.ke..
git tree: upstream
kernel config: https://syzkaller.appspot.com/x/.config?x=902c5209311d387c
dashboard link: https://syzkaller.appspot.com/bug?extid=b05dabaed0b1f0b0a5e4
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14f2c009f00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11b20b35f00000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: printk: add kthread console printers

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

[Hillf Danton]

On Mon, 14 Feb 2022 22:57:20 -0800

To fix uaf, mark skb freed to avoid double free.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git 4378e427f705

--- y/drivers/net/wireless/ath/ath9k/hif_usb.c
+++ h/drivers/net/wireless/ath/ath9k/hif_usb.c
@@ -711,6 +711,7 @@ static void ath9k_hif_usb_reg_in_cb(stru
struct sk_buff *skb = rx_buf->skb;
struct sk_buff *nskb;
int ret;
+ bool freed = false;

if (!skb)
return;
@@ -739,8 +740,7 @@ static void ath9k_hif_usb_reg_in_cb(stru
/* Process the command first */
ath9k_htc_rx_msg(hif_dev->htc_handle, skb,
skb->len, USB_REG_IN_PIPE);
-
-
+ freed = true;
nskb = alloc_skb(MAX_REG_IN_BUF_SIZE, GFP_ATOMIC);
if (!nskb) {
dev_err(&hif_dev->udev->dev,
@@ -768,7 +768,8 @@ resubmit:

return;
free:
- kfree_skb(skb);
+ if (!freed)
+ kfree_skb(skb);
kfree(rx_buf);
urb->context = NULL;
}
--

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+b05dab...@syzkaller.appspotmail.com

Tested on:

commit: 4378e427 usbip: vudc: Make use of the helper macro LIS..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
console output: https://syzkaller.appspot.com/x/log.txt?x=16ef952ff00000
kernel config: https://syzkaller.appspot.com/x/.config?x=ceddcfc6e4531984

dashboard link: https://syzkaller.appspot.com/bug?extid=b05dabaed0b1f0b0a5e4
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=1199603ff00000

Note: testing is done by a robot and is best-effort only.

[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.