================================================================== BUG: KASAN: slab-out-of-bounds in tcp_retransmit_timer+0x2d4c/0x3240 net/ipv4/tcp_timer.c:500 Read of size 8 at addr ffff88806940c350 by task syz-executor.1/24003 CPU: 1 PID: 24003 Comm: syz-executor.1 Not tainted 5.8.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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 do_softirq kernel/softirq.c:337 [inline] do_softirq+0x16b/0x1e0 kernel/softirq.c:324 __local_bh_enable_ip+0x1f8/0x250 kernel/softirq.c:189 local_bh_enable include/linux/bottom_half.h:32 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:723 [inline] __dev_queue_xmit+0x1aa6/0x2d60 net/core/dev.c:4158 __bpf_tx_skb net/core/filter.c:2086 [inline] __bpf_redirect_no_mac net/core/filter.c:2111 [inline] __bpf_redirect+0x52e/0xc60 net/core/filter.c:2134 ____bpf_clone_redirect net/core/filter.c:2165 [inline] bpf_clone_redirect+0x2ae/0x420 net/core/filter.c:2137 bpf_prog_bebbfe2050753572+0x5c/0x308 bpf_dispatcher_nop_func include/linux/bpf.h:556 [inline] bpf_test_run+0x3bb/0xc70 net/bpf/test_run.c:49 bpf_prog_test_run_skb+0x98b/0x14f0 net/bpf/test_run.c:459 bpf_prog_test_run kernel/bpf/syscall.c:2983 [inline] __do_sys_bpf+0x2117/0x4b10 kernel/bpf/syscall.c:4130 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cb29 Code: Bad RIP value. RSP: 002b:00007f8b86364c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00000000004dada0 RCX: 000000000045cb29 RDX: 0000000000000028 RSI: 00000000200000c0 RDI: 000000000000000a RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000005d R14: 00000000004c32db R15: 00007f8b863656d4 Allocated by task 23371: 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 fs/namei.c:2646 [inline] user_path_at_empty+0xa1/0x100 fs/namei.c:2646 user_path_at include/linux/namei.h:59 [inline] do_faccessat+0x129/0x820 fs/open.c:423 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 23371: 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 filename_lookup+0x3b1/0x560 fs/namei.c:2376 user_path_at include/linux/namei.h:59 [inline] do_faccessat+0x129/0x820 fs/open.c:423 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 ffff88806940ce80 which belongs to the cache names_cache of size 4096 The buggy address is located 2864 bytes to the left of 4096-byte region [ffff88806940ce80, ffff88806940de80) The buggy address belongs to the page: page:ffffea0001a50300 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 head:ffffea0001a50300 order:1 compound_mapcount:0 flags: 0xfffe0000010200(slab|head) raw: 00fffe0000010200 ffffea00027ca888 ffffea00025fa908 ffff8880aa1d0000 raw: 0000000000000000 ffff88806940ce80 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88806940c200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806940c280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88806940c300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88806940c380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806940c400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================