==================================================================
BUG: KASAN: slab-out-of-bounds in tcp_retransmit_timer+0x2d30/0x3220 net/ipv4/tcp_timer.c:499
Read of size 8 at addr ffff8880969c2250 by task syz-fuzzer/6890

CPU: 1 PID: 6890 Comm: syz-fuzzer Not tainted 5.9.0-rc6-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+0x198/0x1fd lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 tcp_retransmit_timer+0x2d30/0x3220 net/ipv4/tcp_timer.c:499
 tcp_write_timer_handler+0x79b/0xa60 net/ipv4/tcp_timer.c:610
 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:630
 call_timer_fn+0x1ac/0x760 kernel/time/timer.c:1413
 expire_timers kernel/time/timer.c:1458 [inline]
 __run_timers.part.0+0x67c/0xaa0 kernel/time/timer.c:1755
 __run_timers kernel/time/timer.c:1736 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1768
 __do_softirq+0x1f8/0xb23 kernel/softirq.c:298
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 do_softirq_own_stack+0x9d/0xd0 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:393 [inline]
 __irq_exit_rcu kernel/softirq.c:423 [inline]
 irq_exit_rcu+0x235/0x280 kernel/softirq.c:435
 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0033:0x4f7bdb
Code: 08 90 48 8b 50 08 48 8b 49 18 48 89 14 24 ff d1 48 8b 54 24 08 48 c1 fa 20 8b 4c 24 14 39 ca 7f d8 89 d0 8b 4c 24 30 99 f7 f9 <89> 54 24 38 48 8b 6c 24 18 48 83 c4 20 c3 89 54 24 10 48 8b 44 24
RSP: 002b:000000c00193acb8 EFLAGS: 00000283
RAX: 0000000000009012 RBX: b10381db73f4c925 RCX: 00000000000032b7
RDX: 0000000000000b8d RSI: 00000000000001b7 RDI: 000000c00b8ba4b0
RBP: 000000c00193acd0 R08: 0000000000879320 R09: 0000000000000001
R10: 000000c00c9e2000 R11: 0000000000000501 R12: 0000000000000010
R13: 0000000000000009 R14: 000080c00c9e2000 R15: 000080c00ca03fff

Allocated by task 6904:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461
 slab_post_alloc_hook mm/slab.h:518 [inline]
 slab_alloc mm/slab.c:3312 [inline]
 kmem_cache_alloc+0x13a/0x3f0 mm/slab.c:3482
 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138
 getname_flags include/linux/audit.h:320 [inline]
 getname fs/namei.c:209 [inline]
 __do_sys_unlink fs/namei.c:3942 [inline]
 __se_sys_unlink fs/namei.c:3940 [inline]
 __x64_sys_unlink+0xb1/0x100 fs/namei.c:3940
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 6904:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56
 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355
 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422
 __cache_free mm/slab.c:3418 [inline]
 kmem_cache_free.part.0+0x74/0x1e0 mm/slab.c:3693
 putname+0xe1/0x120 fs/namei.c:259
 do_unlinkat+0x12b/0x660 fs/namei.c:3917
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff8880969c2b40
 which belongs to the cache names_cache of size 4096
The buggy address is located 2288 bytes to the left of
 4096-byte region [ffff8880969c2b40, ffff8880969c3b40)
The buggy address belongs to the page:
page:00000000b5d76ef5 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x969c2
head:00000000b5d76ef5 order:1 compound_mapcount:0
flags: 0xfffe0000010200(slab|head)
raw: 00fffe0000010200 ffffea00025f5188 ffffea0002761b08 ffff8880aa221c00
raw: 0000000000000000 ffff8880969c2b40 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880969c2100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880969c2180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880969c2200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                 ^
 ffff8880969c2280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880969c2300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================