================================================================== BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:378 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler net/ipv4/tcp_timer.c:624 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler+0x998/0x9f0 net/ipv4/tcp_timer.c:594 Read of size 1 at addr ffff88805e1c8765 by task swapper/3/0 CPU: 3 PID: 0 Comm: swapper/3 Not tainted 6.0.0-rc1-syzkaller-00368-gf31c32efd57c #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold+0x2ba/0x6e9 mm/kasan/report.c:433 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495 tcp_probe_timer net/ipv4/tcp_timer.c:378 [inline] tcp_write_timer_handler net/ipv4/tcp_timer.c:624 [inline] tcp_write_timer_handler+0x998/0x9f0 net/ipv4/tcp_timer.c:594 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:637 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers.part.0+0x674/0xa80 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803 __do_softirq+0x1d3/0x9c6 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:731 Code: f8 e9 8c fd ff ff 4c 89 f7 e8 61 a2 44 f8 e9 3a fd ff ff cc cc cc cc cc cc cc cc cc cc cc cc 66 90 0f 00 2d 37 a0 64 00 fb f4 0f 1f 40 00 41 54 be 08 00 00 00 53 65 48 8b 1c 25 80 6f 02 00 RSP: 0018:ffffc9000069fe00 EFLAGS: 00000246 RAX: 00000000001691ff RBX: ffff888012536080 RCX: ffffffff897f2795 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000003 R08: 0000000000000001 R09: ffff88802cb34c4b R10: ffffed1005966989 R11: 0000000000000000 R12: ffffed10024a6c10 R13: 0000000000000003 R14: ffffffff8dddf090 R15: 0000000000000000 default_idle_call+0x80/0xc0 kernel/sched/idle.c:109 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x401/0x590 kernel/sched/idle.c:303 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:400 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:262 secondary_startup_64_no_verify+0xce/0xdb Allocated by task 6749: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] __kasan_slab_alloc+0x85/0xb0 mm/kasan/common.c:470 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:727 [inline] slab_alloc mm/slab.c:3294 [inline] __kmem_cache_alloc_lru mm/slab.c:3471 [inline] kmem_cache_alloc+0x214/0x520 mm/slab.c:3491 kmem_cache_zalloc include/linux/slab.h:723 [inline] net_alloc net/core/net_namespace.c:404 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:459 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x480 kernel/nsproxy.c:178 copy_process+0x305c/0x7090 kernel/fork.c:2259 kernel_clone+0xe7/0xab0 kernel/fork.c:2673 __do_sys_clone+0xba/0x100 kernel/fork.c:2807 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0x7e/0x90 mm/kasan/generic.c:348 insert_work+0x48/0x350 kernel/workqueue.c:1358 __queue_work+0x625/0x1210 kernel/workqueue.c:1517 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1514 [inline] __run_timers.part.0+0x4a3/0xa80 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0x152/0x1d0 kernel/time/timer.c:1805 __do_softirq+0x1d3/0x9c6 kernel/softirq.c:571 The buggy address belongs to the object at ffff88805e1c80c0 which belongs to the cache net_namespace of size 6784 The buggy address is located 1701 bytes inside of 6784-byte region [ffff88805e1c80c0, ffff88805e1c9b40) The buggy address belongs to the physical page: page:ffffea0001787200 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805e1c80c0 pfn:0x5e1c8 head:ffffea0001787200 order:1 compound_mapcount:0 compound_pincount:0 memcg:ffff888067d36a41 flags: 0x4fff00000010200(slab|head|node=1|zone=1|lastcpupid=0x7ff) raw: 04fff00000010200 ffffea00018a3308 ffffea00018c3288 ffff8880121e0400 raw: ffff88805e1c80c0 ffff88805e1c80c0 0000000100000000 ffff888067d36a41 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x40cc0(GFP_KERNEL|__GFP_COMP), pid 3693, tgid 3693 (syz-executor.3), ts 93136180797, free_ts 0 prep_new_page mm/page_alloc.c:2532 [inline] get_page_from_freelist+0x109b/0x2ce0 mm/page_alloc.c:4283 __alloc_pages+0x1c7/0x510 mm/page_alloc.c:5515 __alloc_pages_node include/linux/gfp.h:243 [inline] kmem_getpages mm/slab.c:1363 [inline] cache_grow_begin+0x75/0x360 mm/slab.c:2569 fallback_alloc+0x1e2/0x2d0 mm/slab.c:3112 __do_cache_alloc mm/slab.c:3253 [inline] slab_alloc mm/slab.c:3287 [inline] __kmem_cache_alloc_lru mm/slab.c:3471 [inline] kmem_cache_alloc+0x30d/0x520 mm/slab.c:3491 kmem_cache_zalloc include/linux/slab.h:723 [inline] net_alloc net/core/net_namespace.c:404 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:459 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:227 ksys_unshare+0x445/0x920 kernel/fork.c:3183 __do_sys_unshare kernel/fork.c:3254 [inline] __se_sys_unshare kernel/fork.c:3252 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3252 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page_owner free stack trace missing Memory state around the buggy address: ffff88805e1c8600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805e1c8680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805e1c8700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805e1c8780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805e1c8800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: f8 clc 1: e9 8c fd ff ff jmpq 0xfffffd92 6: 4c 89 f7 mov %r14,%rdi 9: e8 61 a2 44 f8 callq 0xf844a26f e: e9 3a fd ff ff jmpq 0xfffffd4d 13: cc int3 14: cc int3 15: cc int3 16: cc int3 17: cc int3 18: cc int3 19: cc int3 1a: cc int3 1b: cc int3 1c: cc int3 1d: cc int3 1e: cc int3 1f: 66 90 xchg %ax,%ax 21: 0f 00 2d 37 a0 64 00 verw 0x64a037(%rip) # 0x64a05f 28: fb sti 29: f4 hlt * 2a: c3 retq <-- trapping instruction 2b: 0f 1f 40 00 nopl 0x0(%rax) 2f: 41 54 push %r12 31: be 08 00 00 00 mov $0x8,%esi 36: 53 push %rbx 37: 65 48 8b 1c 25 80 6f mov %gs:0x26f80,%rbx 3e: 02 00