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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:1066 [inline]
BUG: KASAN: use-after-free in consume_skb+0x2e/0x160 net/core/skbuff.c:908
Read of size 4 at addr ffff88803af5535c by task syz-executor.4/11394

CPU: 0 PID: 11394 Comm: syz-executor.4 Not tainted 5.15.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:256
 __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:1066 [inline]
 consume_skb+0x2e/0x160 net/core/skbuff.c:908
 __sk_msg_free+0x26d/0x360 net/core/skmsg.c:196
 sk_msg_free net/core/skmsg.c:209 [inline]
 __sk_psock_purge_ingress_msg net/core/skmsg.c:724 [inline]
 __sk_psock_zap_ingress net/core/skmsg.c:742 [inline]
 sk_psock_stop+0x415/0x620 net/core/skmsg.c:760
 sock_map_close+0x34a/0x780 net/core/sock_map.c:1516
 unix_release+0x7a/0xe0 net/unix/af_unix.c:948
 __sock_release+0xcd/0x280 net/socket.c:649
 sock_close+0x18/0x20 net/socket.c:1314
 __fput+0x288/0x9f0 fs/file_table.c:280
 task_work_run+0xdd/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fb6f84fa67b
Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44
RSP: 002b:00007fffe571c180 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 00007fb6f84fa67b
RDX: 0000000000000000 RSI: ffffffff84378bcc RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000001b2e725124
R10: 00000000000009ef R11: 0000000000000293 R12: 00007fb6f864bb60
R13: 00007fb6f864bb60 R14: 00007fb6f864af60 R15: 000000000017447e

Allocated by task 11399:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x83/0xb0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:3213 [inline]
 slab_alloc mm/slub.c:3221 [inline]
 kmem_cache_alloc+0x209/0x390 mm/slub.c:3226
 skb_clone+0x170/0x3c0 net/core/skbuff.c:1521
 sk_psock_verdict_recv+0x72/0x7e0 net/core/skmsg.c:1120
 unix_read_sock+0xd7/0x250 net/unix/af_unix.c:2420
 sk_psock_verdict_data_ready+0x11a/0x180 net/core/skmsg.c:1163
 unix_dgram_sendmsg+0xfa7/0x1950 net/unix/af_unix.c:1941
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 ____sys_sendmsg+0x331/0x810 net/socket.c:2409
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463
 __sys_sendmmsg+0x195/0x470 net/socket.c:2549
 __do_sys_sendmmsg net/socket.c:2578 [inline]
 __se_sys_sendmmsg net/socket.c:2575 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2575
 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

Freed by task 20:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free mm/kasan/common.c:328 [inline]
 __kasan_slab_free+0xff/0x130 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1700 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1726
 slab_free mm/slub.c:3492 [inline]
 kmem_cache_free+0x95/0x4e0 mm/slub.c:3508
 kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:700
 __kfree_skb net/core/skbuff.c:757 [inline]
 kfree_skb net/core/skbuff.c:774 [inline]
 kfree_skb+0x140/0x3f0 net/core/skbuff.c:768
 sock_drop include/linux/skmsg.h:309 [inline]
 sk_psock_backlog+0x93b/0xda0 net/core/skmsg.c:644
 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff88803af55280
 which belongs to the cache skbuff_head_cache of size 232
The buggy address is located 220 bytes inside of
 232-byte region [ffff88803af55280, ffff88803af55368)
The buggy address belongs to the page:
page:ffffea0000ebd540 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88803af55140 pfn:0x3af55
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffffea00021096c8 ffffea0000bbf1c8 ffff8881441f3000
raw: ffff88803af55140 00000000000c0006 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 8665, ts 1505413002401, free_ts 1505374334073
 prep_new_page mm/page_alloc.c:2424 [inline]
 get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4153
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5375
 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2191
 alloc_slab_page mm/slub.c:1770 [inline]
 allocate_slab mm/slub.c:1907 [inline]
 new_slab+0x319/0x490 mm/slub.c:1970
 ___slab_alloc+0x950/0x1050 mm/slub.c:3001
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3088
 slab_alloc_node mm/slub.c:3179 [inline]
 kmem_cache_alloc_node+0x11f/0x3d0 mm/slub.c:3249
 __alloc_skb+0x20b/0x340 net/core/skbuff.c:415
 alloc_skb include/linux/skbuff.h:1116 [inline]
 alloc_skb_with_frags+0x93/0x620 net/core/skbuff.c:6083
 sock_alloc_send_pskb+0x783/0x910 net/core/sock.c:2493
 unix_dgram_sendmsg+0x3ec/0x1950 net/unix/af_unix.c:1811
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 ____sys_sendmsg+0x331/0x810 net/socket.c:2409
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463
 __sys_sendmmsg+0x195/0x470 net/socket.c:2549
 __do_sys_sendmmsg net/socket.c:2578 [inline]
 __se_sys_sendmmsg net/socket.c:2575 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2575
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1338 [inline]
 free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1389
 free_unref_page_prepare mm/page_alloc.c:3315 [inline]
 free_unref_page_list+0x1a9/0xfa0 mm/page_alloc.c:3431
 release_pages+0x830/0x20b0 mm/swap.c:963
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:242 [inline]
 tlb_flush_mmu mm/mmu_gather.c:249 [inline]
 tlb_finish_mmu+0x165/0x8c0 mm/mmu_gather.c:340
 exit_mmap+0x1ea/0x630 mm/mmap.c:3173
 __mmput+0x122/0x4b0 kernel/fork.c:1115
 mmput+0x58/0x60 kernel/fork.c:1136
 free_bprm+0x65/0x2e0 fs/exec.c:1483
 kernel_execve+0x380/0x460 fs/exec.c:1980
 call_usermodehelper_exec_async+0x2e3/0x580 kernel/umh.c:112
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff88803af55200: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
 ffff88803af55280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88803af55300: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
                                                    ^
 ffff88803af55380: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff88803af55400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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