audit: type=1800 audit(1620800351.374:154): pid=15378 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed comm="syz-executor.5" name="bus" dev="sda1" ino=13986 res=0 ================================================================== BUG: KASAN: use-after-free in tcp_retransmit_timer+0x305e/0x3470 net/ipv4/tcp_timer.c:485 Read of size 8 at addr ffff888046e28378 by task systemd-udevd/15350 CPU: 1 PID: 15350 Comm: systemd-udevd Not tainted 4.19.190-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+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433 tcp_retransmit_timer+0x305e/0x3470 net/ipv4/tcp_timer.c:485 tcp_write_timer_handler+0x5e6/0xa60 net/ipv4/tcp_timer.c:598 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:1696 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709 __do_softirq+0x265/0x980 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:535 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:deref_stack_regs arch/x86/kernel/unwind_orc.c:349 [inline] RIP: 0010:unwind_next_frame+0xcd3/0x1400 arch/x86/kernel/unwind_orc.c:515 Code: 00 00 00 fc ff df 48 8d b8 80 00 00 00 e8 75 ef ff ff 4c 89 e7 4c 8b 44 24 30 48 c1 ef 03 48 8b 84 24 a8 00 00 00 80 3c 17 00 <0f> 85 03 06 00 00 48 8b 7c 24 28 49 89 46 48 48 81 c7 98 00 00 00 RSP: 0018:ffff88803fddf6c8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 00007fef32e227da RBX: 1ffff11007fbbee2 RCX: 1ffff11007fbbf01 RDX: dffffc0000000000 RSI: ffff88803fddf770 RDI: 1ffff11007fbbf08 RBP: 0000000000000001 R08: ffffffff8c119e4c R09: ffffffff8c119e2a R10: ffff88803fddf857 R11: 0000000000074071 R12: ffff88803fddf840 R13: ffff88803fddf82d R14: ffff88803fddf7f8 R15: ffffffff8c119e48 __save_stack_trace+0x9f/0x190 arch/x86/kernel/stacktrace.c:44 save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc mm/slab.c:3397 [inline] kmem_cache_alloc+0x110/0x370 mm/slab.c:3557 kmem_cache_zalloc include/linux/slab.h:699 [inline] __alloc_file+0x21/0x330 fs/file_table.c:100 alloc_empty_file+0x6d/0x170 fs/file_table.c:150 path_openat+0xe9/0x2df0 fs/namei.c:3526 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fef32e227da Code: 75 3e 89 d0 45 31 d2 25 00 00 41 00 3d 00 00 41 00 74 2d 8b 05 37 2f 2c 00 85 c0 75 51 48 63 d2 48 63 ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 8a 00 00 00 48 83 c4 60 5b 5d 41 5c c3 90 RSP: 002b:00007ffcc5e609f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ffcc5e62bc0 RCX: 00007fef32e227da RDX: 0000000000080000 RSI: 00007fef3397e31f RDI: 0000000000000011 RBP: 00007fef3397e31f R08: 0000000000000000 R09: 0000000000000020 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000 R13: 00007ffcc5e62bd8 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 8113: kmem_cache_alloc+0x122/0x370 mm/slab.c:3559 kmem_cache_zalloc include/linux/slab.h:699 [inline] net_alloc net/core/net_namespace.c:385 [inline] copy_net_ns+0x106/0x340 net/core/net_namespace.c:425 create_new_namespaces+0x3f6/0x7b0 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x36c/0x9a0 kernel/fork.c:2541 __do_sys_unshare kernel/fork.c:2609 [inline] __se_sys_unshare kernel/fork.c:2607 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2607 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7: __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x7f/0x260 mm/slab.c:3765 net_free net/core/net_namespace.c:401 [inline] net_drop_ns+0x73/0x90 net/core/net_namespace.c:408 cleanup_net+0x64c/0x8b0 net/core/net_namespace.c:571 process_one_work+0x864/0x1570 kernel/workqueue.c:2152 worker_thread+0x64c/0x1130 kernel/workqueue.c:2295 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 The buggy address belongs to the object at ffff888046e28140 which belongs to the cache net_namespace of size 8704 The buggy address is located 568 bytes inside of 8704-byte region [ffff888046e28140, ffff888046e2a340) The buggy address belongs to the page: page:ffffea00011b8a00 count:1 mapcount:0 mapping:ffff88823b843e00 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea00011dcd08 ffffea00011a4408 ffff88823b843e00 raw: 0000000000000000 ffff888046e28140 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888046e28200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888046e28280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888046e28300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888046e28380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888046e28400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================