================================================================== BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:360 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler+0x8c6/0x8d0 net/ipv4/tcp_timer.c:596 Read of size 4 at addr ffff88805e6b4990 by task kworker/1:4/9896 CPU: 1 PID: 9896 Comm: kworker/1:4 Not tainted 5.3.0-rc3+ #153 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: rcu_gp process_srcu Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482 kasan_report+0x12/0x17 mm/kasan/common.c:612 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 tcp_probe_timer net/ipv4/tcp_timer.c:360 [inline] tcp_write_timer_handler+0x8c6/0x8d0 net/ipv4/tcp_timer.c:596 tcp_write_timer+0xa8/0x1e0 net/ipv4/tcp_timer.c:612 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322 expire_timers kernel/time/timer.c:1366 [inline] __run_timers kernel/time/timer.c:1685 [inline] __run_timers kernel/time/timer.c:1653 [inline] run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:537 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1095 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 RIP: 0010:preempt_count_add+0x44/0x160 kernel/sched/core.c:3615 Code: 83 e0 07 48 c1 e9 03 53 83 c0 03 89 fb 0f b6 14 11 38 d0 7c 08 84 d2 0f 85 00 01 00 00 8b 15 13 6b 3c 09 65 01 1d 94 27 b3 7e <85> d2 75 11 65 8b 05 89 27 b3 7e 0f b6 c0 3d f4 00 00 00 7f 7f 65 RSP: 0018:ffff8880680c7b90 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000003 RBX: 0000000000000001 RCX: 1ffffffff1516830 RDX: 0000000000000000 RSI: ffffffff833e20bc RDI: 0000000000000001 RBP: ffff8880680c7ba0 R08: ffff8880a3e7a0c0 R09: 0000000000000040 R10: 0000000000000040 R11: ffffffff8a8d3967 R12: 000001d154bd2da2 R13: 0000000000000001 R14: 0000000000002ced R15: 00000000000352d7 delay_tsc+0x3d/0xc0 arch/x86/lib/delay.c:68 __delay arch/x86/lib/delay.c:161 [inline] __const_udelay+0x59/0x80 arch/x86/lib/delay.c:175 try_check_zero+0x201/0x330 kernel/rcu/srcutree.c:705 srcu_advance_state kernel/rcu/srcutree.c:1142 [inline] process_srcu+0x329/0xe20 kernel/rcu/srcutree.c:1237 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 26862: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:487 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:460 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:495 slab_post_alloc_hook mm/slab.h:520 [inline] slab_alloc mm/slab.c:3319 [inline] kmem_cache_alloc+0x121/0x710 mm/slab.c:3483 getname_flags fs/namei.c:138 [inline] getname_flags+0xd6/0x5b0 fs/namei.c:128 getname fs/namei.c:209 [inline] do_symlinkat+0x8b/0x290 fs/namei.c:4143 __do_sys_symlink fs/namei.c:4173 [inline] __se_sys_symlink fs/namei.c:4171 [inline] __x64_sys_symlink+0x59/0x80 fs/namei.c:4171 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 26862: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:449 kasan_slab_free+0xe/0x10 mm/kasan/common.c:457 __cache_free mm/slab.c:3425 [inline] kmem_cache_free+0x86/0x320 mm/slab.c:3693 putname+0xef/0x130 fs/namei.c:259 do_symlinkat+0x181/0x290 fs/namei.c:4161 __do_sys_symlink fs/namei.c:4173 [inline] __se_sys_symlink fs/namei.c:4171 [inline] __x64_sys_symlink+0x59/0x80 fs/namei.c:4171 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff88805e6b4000 which belongs to the cache names_cache of size 4096 The buggy address is located 2448 bytes inside of 4096-byte region [ffff88805e6b4000, ffff88805e6b5000) The buggy address belongs to the page: page:ffffea000179ad00 refcount:1 mapcount:0 mapping:ffff88821bc46380 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0001b11308 ffffea000160f708 ffff88821bc46380 raw: 0000000000000000 ffff88805e6b4000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88805e6b4880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805e6b4900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805e6b4980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805e6b4a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805e6b4a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================