syzbot

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BUG: KASAN: slab-out-of-bounds in tcp_orphan_retries net/ipv4/tcp_timer.c:139 [inline]
BUG: KASAN: slab-out-of-bounds in tcp_probe_timer net/ipv4/tcp_timer.c:374 [inline]
BUG: KASAN: slab-out-of-bounds in tcp_write_timer_handler+0xa4b/0xa60 net/ipv4/tcp_timer.c:602
Read of size 4 at addr ffff8880a41d8828 by task swapper/1/0

CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.19.145-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2fe lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1c7 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load4_noabort+0x88/0x90 mm/kasan/report.c:432
 tcp_orphan_retries net/ipv4/tcp_timer.c:139 [inline]
 tcp_probe_timer net/ipv4/tcp_timer.c:374 [inline]
 tcp_write_timer_handler+0xa4b/0xa60 net/ipv4/tcp_timer.c:602
 tcp_write_timer+0x103/0x1b0 net/ipv4/tcp_timer.c:618
 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338
 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375
 __run_timers kernel/time/timer.c:1703 [inline]
 run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1716
 __do_softirq+0x26c/0x9a0 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x215/0x260 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:544 [inline]
 smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1094
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: 48 89 df e8 44 1c 61 fa e9 2e ff ff ff 48 89 df e8 37 1c 61 fa eb 82 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 24 2b 49 00 fb f4 <c3> 90 e9 07 00 00 00 0f 00 2d 14 2b 49 00 f4 c3 90 90 41 56 41 55
RSP: 0018:ffff8880a9f4fd58 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11a4b6c RBX: dffffc0000000000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff8880a9f3cc44
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff88d25b50
R13: 1ffff110153e9fb5 R14: 0000000000000000 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0x49/0x310 arch/x86/kernel/process.c:557
 cpuidle_idle_call kernel/sched/idle.c:153 [inline]
 do_idle+0x2ec/0x4b0 kernel/sched/idle.c:263
 cpu_startup_entry+0xc5/0xe0 kernel/sched/idle.c:369
 start_secondary+0x41f/0x580 arch/x86/kernel/smpboot.c:271
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243

Allocated by task 3696:
 kmem_cache_alloc+0x122/0x370 mm/slab.c:3559
 getname_flags+0xce/0x590 fs/namei.c:140
 do_sys_open+0x26c/0x520 fs/open.c:1079
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 3696:
 __cache_free mm/slab.c:3503 [inline]
 kmem_cache_free+0x7f/0x260 mm/slab.c:3765
 putname+0xe1/0x120 fs/namei.c:261
 do_sys_open+0x2ba/0x520 fs/open.c:1094
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880a41d8900
 which belongs to the cache names_cache of size 4096
The buggy address is located 216 bytes to the left of
 4096-byte region [ffff8880a41d8900, ffff8880a41d9900)
The buggy address belongs to the page:
page:ffffea0002907600 count:1 mapcount:0 mapping:ffff8880aa00ab40 index:0x0 compound_mapcount: 0
flags: 0xfffe0000008100(slab|head)
raw: 00fffe0000008100 ffffea000245a608 ffffea0002907688 ffff8880aa00ab40
raw: 0000000000000000 ffff8880a41d8900 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a41d8700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a41d8780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880a41d8800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                  ^
 ffff8880a41d8880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a41d8900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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