[drm:drm_calc_timestamping_constants] *ERROR* crtc 29: Can't calculate constants, dotclock = 0! ================================================================== BUG: KASAN: use-after-free in tcp_retransmit_timer+0x2fc3/0x33f0 net/ipv4/tcp_timer.c:480 Read of size 8 at addr ffff8880a4c18338 by task systemd-udevd/4698 CPU: 1 PID: 4698 Comm: systemd-udevd Not tainted 4.19.211-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+0x2fc3/0x33f0 net/ipv4/tcp_timer.c:480 tcp_write_timer_handler+0x5e6/0xa60 net/ipv4/tcp_timer.c:593 tcp_write_timer+0x103/0x1b0 net/ipv4/tcp_timer.c:613 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:536 [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:check_memory_region_inline mm/kasan/kasan.c:251 [inline] RIP: 0010:check_memory_region+0x9/0x170 mm/kasan/kasan.c:267 Code: 48 c1 ee 03 0f b6 04 06 84 c0 74 d8 83 e2 07 38 d0 7e d7 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 85 f6 0f 84 3f 01 00 00 <48> b8 ff ff ff ff ff 7f ff ff 44 0f b6 c2 48 39 c7 0f 86 20 01 00 RSP: 0018:ffff88809a80f760 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000001 RBX: ffff8880ba122ac0 RCX: ffffffff81518c83 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880ba122ad0 RBP: ffff8880ba122ad0 R08: 00000000594ea6fa R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000074071 R12: ffff88809a80f890 R13: 0000000000000000 R14: ffff88813be45080 R15: 00000000000001c8 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline] rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:350 [inline] rcu_is_watching+0x53/0xc0 kernel/rcu/tree.c:1025 rcu_read_lock include/linux/rcupdate.h:628 [inline] is_bpf_text_address+0x14d/0x1b0 kernel/bpf/core.c:546 kernel_text_address kernel/extable.c:152 [inline] kernel_text_address+0xbd/0xf0 kernel/extable.c:122 __kernel_text_address+0x9/0x30 kernel/extable.c:107 unwind_get_return_address arch/x86/kernel/unwind_orc.c:297 [inline] unwind_get_return_address+0x51/0x90 arch/x86/kernel/unwind_orc.c:292 __save_stack_trace+0xaf/0x190 arch/x86/kernel/stacktrace.c:45 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 kmem_cache_alloc+0x122/0x370 mm/slab.c:3559 kmem_cache_zalloc include/linux/slab.h:699 [inline] __alloc_file+0x21/0x340 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: 0033:0x7fc94769a9b1 Code: f7 d8 bf ff ff ff ff 64 89 02 eb cb 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 80 3f 00 74 1b be 00 08 09 00 b8 02 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 1f 89 c7 e9 00 ff ff ff 48 8b 05 b1 54 2e 00 RSP: 002b:00007ffdd1817578 EFLAGS: 00000202 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000056073c53e4f0 RCX: 00007fc94769a9b1 RDX: 00000000000000ff RSI: 0000000000090800 RDI: 000056073c5311d0 RBP: 00007fc948850710 R08: 000056073c52fcb0 R09: 0000000000001010 R10: 00007fc947980b58 R11: 0000000000000202 R12: 0000000000000000 R13: 000056073c5311d0 R14: 00000000000000ff R15: 000056073c5311d0 Allocated by task 8146: 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:386 [inline] copy_net_ns+0x106/0x340 net/core/net_namespace.c:426 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:2542 __do_sys_unshare kernel/fork.c:2610 [inline] __se_sys_unshare kernel/fork.c:2608 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2608 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9449: __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x7f/0x260 mm/slab.c:3765 net_free net/core/net_namespace.c:402 [inline] net_drop_ns+0x73/0x90 net/core/net_namespace.c:409 cleanup_net+0x64c/0x8b0 net/core/net_namespace.c:572 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 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 ffff8880a4c18100 which belongs to the cache net_namespace of size 8704 The buggy address is located 568 bytes inside of 8704-byte region [ffff8880a4c18100, ffff8880a4c1a300) The buggy address belongs to the page: page:ffffea0002930600 count:1 mapcount:0 mapping:ffff88823b843e00 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea00025e2a08 ffffea0002896e08 ffff88823b843e00 raw: 0000000000000000 ffff8880a4c18100 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a4c18200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a4c18280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880a4c18300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a4c18380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a4c18400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 48 c1 ee 03 shr $0x3,%rsi 4: 0f b6 04 06 movzbl (%rsi,%rax,1),%eax 8: 84 c0 test %al,%al a: 74 d8 je 0xffffffe4 c: 83 e2 07 and $0x7,%edx f: 38 d0 cmp %dl,%al 11: 7e d7 jle 0xffffffea 13: c3 retq 14: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1) 1b: 00 00 00 00 1f: 66 90 xchg %ax,%ax 21: 48 85 f6 test %rsi,%rsi 24: 0f 84 3f 01 00 00 je 0x169 * 2a: 48 b8 ff ff ff ff ff movabs $0xffff7fffffffffff,%rax <-- trapping instruction 31: 7f ff ff 34: 44 0f b6 c2 movzbl %dl,%r8d 38: 48 39 c7 cmp %rax,%rdi 3b: 0f .byte 0xf 3c: 86 20 xchg %ah,(%rax) 3e: 01 00 add %eax,(%rax)