================================================================== BUG: KASAN: slab-out-of-bounds in tcp_retransmit_timer+0x2d4c/0x3240 net/ipv4/tcp_timer.c:500 Read of size 8 at addr ffff8880a74b6450 by task kworker/u4:4/286 CPU: 1 PID: 286 Comm: kworker/u4:4 Not tainted 5.8.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x436 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+0x2d4c/0x3240 net/ipv4/tcp_timer.c:500 tcp_write_timer_handler+0x79b/0xa60 net/ipv4/tcp_timer.c:611 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:631 call_timer_fn+0x1ac/0x760 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers.part.0+0x54c/0xa20 kernel/time/timer.c:1773 __run_timers kernel/time/timer.c:1745 [inline] run_timer_softirq+0xae/0x1a0 kernel/time/timer.c:1786 __do_softirq+0x34c/0xa60 kernel/softirq.c:292 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:711 __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+0x111/0x170 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:387 [inline] __irq_exit_rcu kernel/softirq.c:417 [inline] irq_exit_rcu+0x229/0x270 kernel/softirq.c:429 sysvec_apic_timer_interrupt+0x12d/0x220 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:596 RIP: 0010:batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:404 [inline] RIP: 0010:batadv_nc_worker+0x7cf/0xe50 net/batman-adv/network-coding.c:718 Code: 44 24 48 83 44 24 3c 01 48 c1 e8 03 42 0f b6 04 30 84 c0 74 08 3c 03 0f 8e 66 06 00 00 48 8b 44 24 40 44 8b 7c 24 3c 8b 58 10 <44> 89 ff 89 de e8 57 50 aa f9 41 39 df 0f 82 fe f8 ff ff e8 49 54 RSP: 0018:ffffc90001c37c80 EFLAGS: 00000246 RAX: ffff888096e70b00 RBX: 0000000000000400 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffffffff89bbe640 RDI: 0000000000000282 RBP: 0000000000000001 R08: 0000000000000001 R09: ffff8880a8b14908 R10: fffffbfff155c489 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000237 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Allocated by task 6879: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:494 slab_post_alloc_hook mm/slab.h:586 [inline] slab_alloc mm/slab.c:3320 [inline] kmem_cache_alloc+0x12c/0x3b0 mm/slab.c:3484 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags include/linux/audit.h:302 [inline] getname fs/namei.c:209 [inline] __do_sys_unlink fs/namei.c:3936 [inline] __se_sys_unlink fs/namei.c:3934 [inline] __x64_sys_unlink+0xb1/0x100 fs/namei.c:3934 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 6879: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0xf5/0x140 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kmem_cache_free+0x7f/0x310 mm/slab.c:3694 putname+0xe1/0x120 fs/namei.c:259 do_unlinkat+0x12b/0x660 fs/namei.c:3910 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff8880a74b6700 which belongs to the cache names_cache of size 4096 The buggy address is located 688 bytes to the left of 4096-byte region [ffff8880a74b6700, ffff8880a74b7700) The buggy address belongs to the page: page:ffffea00029d2d80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 head:ffffea00029d2d80 order:1 compound_mapcount:0 flags: 0xfffe0000010200(slab|head) raw: 00fffe0000010200 ffffea0002441d88 ffffea0002898d08 ffff8880aa1d0000 raw: 0000000000000000 ffff8880a74b6700 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a74b6300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a74b6380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880a74b6400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880a74b6480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a74b6500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================