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BUG: KASAN: use-after-free in smc_fback_error_report+0x96/0xa0 net/smc/af_smc.c:772
Read of size 8 at addr ffff888016129ba8 by task syz-fuzzer/3587

CPU: 1 PID: 3587 Comm: syz-fuzzer Tainted: G        W         5.17.0-syzkaller-13517-gc3efcedd272a #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+0xeb/0x495 mm/kasan/report.c:313
 print_report mm/kasan/report.c:429 [inline]
 kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491
 smc_fback_error_report+0x96/0xa0 net/smc/af_smc.c:772
 sk_error_report+0x35/0x310 net/core/sock.c:340
 tcp_write_err net/ipv4/tcp_timer.c:71 [inline]
 tcp_write_timeout net/ipv4/tcp_timer.c:276 [inline]
 tcp_retransmit_timer+0x16c5/0x3360 net/ipv4/tcp_timer.c:512
 tcp_write_timer_handler+0x5e6/0xbc0 net/ipv4/tcp_timer.c:622
 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:642
 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+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x45/0xc0 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0033:0x40c6f7
Code: 00 00 0f 83 a2 04 00 00 4c 8d 1d 24 16 6d 00 47 0f b6 14 1a 49 83 fa 44 0f 83 7f 04 00 00 4c 8d 1d ae 92 6c 00 47 0f b7 1c 53 <90> 41 d1 e2 45 0f b6 e1 45 09 e2 45 0f b6 e2 49 81 fc 88 00 00 00
RSP: 002b:000000c00a448f08 EFLAGS: 00000287
RAX: 0000000000000050 RBX: 000000000069aec0 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 000000c000032400 RDI: 000000c00c30f930
RBP: 000000c00a448f78 R08: 00007f6ee5b6a108 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000050 R12: 000000c00c31d0e0
R13: 0000000000000001 R14: 000000c0002536c0 R15: ffffffffffffffff
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0000584a40 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x16129
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 ffffffff00580301 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 3673, tgid 3673 (kworker/0:7), ts 1645630654638, free_ts 1672913384080
 prep_new_page mm/page_alloc.c:2441 [inline]
 get_page_from_freelist+0xba2/0x3df0 mm/page_alloc.c:4182
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408
 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2262
 alloc_slab_page mm/slub.c:1799 [inline]
 allocate_slab+0x26c/0x3c0 mm/slub.c:1944
 new_slab mm/slub.c:2004 [inline]
 ___slab_alloc+0x8df/0xf20 mm/slub.c:3005
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3092
 slab_alloc_node mm/slub.c:3183 [inline]
 __kmalloc_node_track_caller+0x2cb/0x360 mm/slub.c:4947
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 __alloc_skb+0xde/0x340 net/core/skbuff.c:426
 alloc_skb include/linux/skbuff.h:1300 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:742 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:799 [inline]
 nsim_dev_trap_report_work+0x291/0xba0 drivers/net/netdevsim/dev.c:840
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1356 [inline]
 free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1406
 free_unref_page_prepare mm/page_alloc.c:3328 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3423
 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2523
 qlink_free mm/kasan/quarantine.c:157 [inline]
 qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:446
 kasan_slab_alloc include/linux/kasan.h:224 [inline]
 slab_post_alloc_hook mm/slab.h:749 [inline]
 slab_alloc_node mm/slub.c:3217 [inline]
 kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3267
 __alloc_skb+0x215/0x340 net/core/skbuff.c:414
 alloc_skb include/linux/skbuff.h:1300 [inline]
 alloc_skb_with_frags+0x93/0x730 net/core/skbuff.c:5995
 sock_alloc_send_pskb+0x793/0x920 net/core/sock.c:2600
 packet_alloc_skb net/packet/af_packet.c:2910 [inline]
 packet_snd net/packet/af_packet.c:3005 [inline]
 packet_sendmsg+0x1838/0x5470 net/packet/af_packet.c:3089
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 sock_write_iter+0x283/0x3c0 net/socket.c:1061
 call_write_iter include/linux/fs.h:2079 [inline]
 do_iter_readv_writev+0x3d1/0x640 fs/read_write.c:726
 do_iter_write+0x182/0x700 fs/read_write.c:852
 vfs_writev+0x1aa/0x630 fs/read_write.c:925

Memory state around the buggy address:
 ffff888016129a80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888016129b00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888016129b80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                  ^
 ffff888016129c00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888016129c80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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