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BUG: KASAN: slab-out-of-bounds in tcp_retransmit_timer+0x2a66/0x2e80 net/ipv4/tcp_timer.c:500
Read of size 8 at addr ffff8880632f6490 by task kworker/u4:8/14085

CPU: 1 PID: 14085 Comm: kworker/u4:8 Not tainted 5.7.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:382
 __kasan_report.cold+0x20/0x38 mm/kasan/report.c:511
 kasan_report+0x33/0x50 mm/kasan/common.c:625
 tcp_retransmit_timer+0x2a66/0x2e80 net/ipv4/tcp_timer.c:500
 tcp_write_timer_handler+0x686/0x8a0 net/ipv4/tcp_timer.c:611
 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:631
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x623/0x1600 kernel/time/timer.c:1786
 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x192/0x1d0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:546 [inline]
 smp_apic_timer_interrupt+0x19e/0x600 arch/x86/kernel/apic/apic.c:1140
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs+0x31/0xb0 kernel/rcu/tree.c:300
Code: 03 00 48 83 ec 08 e8 0e 2b 3a 02 48 ba 00 00 00 00 00 fc ff df 89 c0 48 8d 3c c5 20 69 60 89 48 89 f9 48 c1 e9 03 80 3c 11 00 <75> 61 48 03 1c c5 20 69 60 89 be 04 00 00 00 48 8d ab d8 00 00 00
RSP: 0018:ffffc90001857ca8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: 0000000000038a40 RCX: 1ffffffff12c0d25
RDX: dffffc0000000000 RSI: ffffffff839a664f RDI: ffffffff89606928
RBP: ffff88805de88bc0 R08: ffff88805b8ac100 R09: ffffed1015ce7164
R10: ffff8880ae738b1b R11: ffffed1015ce7163 R12: 0000000000000001
R13: 00000000000002b0 R14: dffffc0000000000 R15: 0000000000000000
 rcu_is_watching+0xc/0x20 kernel/rcu/tree.c:929
 rcu_read_unlock include/linux/rcupdate.h:651 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:411 [inline]
 batadv_nc_worker+0x47b/0x760 net/batman-adv/network-coding.c:718
 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268
 worker_thread+0x96/0xe20 kernel/workqueue.c:2414
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351

Allocated by task 8617:
 save_stack+0x1b/0x40 mm/kasan/common.c:49
 set_track mm/kasan/common.c:57 [inline]
 __kasan_kmalloc mm/kasan/common.c:495 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:468
 slab_post_alloc_hook mm/slab.h:586 [inline]
 slab_alloc mm/slab.c:3320 [inline]
 kmem_cache_alloc+0x11b/0x740 mm/slab.c:3484
 getname_flags fs/namei.c:138 [inline]
 getname_flags+0xd2/0x5b0 fs/namei.c:128
 getname fs/namei.c:209 [inline]
 do_renameat2+0x176/0xbd0 fs/namei.c:4355
 __do_sys_rename fs/namei.c:4483 [inline]
 __se_sys_rename fs/namei.c:4481 [inline]
 __x64_sys_rename+0x5d/0x80 fs/namei.c:4481
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

Freed by task 8617:
 save_stack+0x1b/0x40 mm/kasan/common.c:49
 set_track mm/kasan/common.c:57 [inline]
 kasan_set_free_info mm/kasan/common.c:317 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:456
 __cache_free mm/slab.c:3426 [inline]
 kmem_cache_free+0x7f/0x320 mm/slab.c:3694
 putname+0xe1/0x120 fs/namei.c:259
 do_renameat2+0x290/0xbd0 fs/namei.c:4459
 __do_sys_rename fs/namei.c:4483 [inline]
 __se_sys_rename fs/namei.c:4481 [inline]
 __x64_sys_rename+0x5d/0x80 fs/namei.c:4481
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

The buggy address belongs to the object at ffff8880632f6e00
 which belongs to the cache names_cache of size 4096
The buggy address is located 2416 bytes to the left of
 4096-byte region [ffff8880632f6e00, ffff8880632f7e00)
The buggy address belongs to the page:
page:ffffea00018cbd80 refcount:1 mapcount:0 mapping:00000000d6be1510 index:0x0 head:ffffea00018cbd80 order:1 compound_mapcount:0
flags: 0xfffe0000010200(slab|head)
raw: 00fffe0000010200 ffffea0002466608 ffffea00017e6e88 ffff8880aa1eb000
raw: 0000000000000000 ffff8880632f6e00 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880632f6380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880632f6400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880632f6480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff8880632f6500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880632f6580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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