================================================================== 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+0x7e2/0x920 net/ipv4/tcp_timer.c:624 Read of size 1 at addr ffff88807be13fc5 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description+0x74/0x340 mm/kasan/report.c:284 print_report+0x107/0x220 mm/kasan/report.c:395 kasan_report+0x139/0x170 mm/kasan/report.c:495 tcp_probe_timer net/ipv4/tcp_timer.c:378 [inline] tcp_write_timer_handler+0x7e2/0x920 net/ipv4/tcp_timer.c:624 tcp_write_timer+0x176/0x280 net/ipv4/tcp_timer.c:637 call_timer_fn+0xf5/0x210 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers+0x76a/0x980 kernel/time/timer.c:1790 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803 __do_softirq+0x277/0x75b kernel/softirq.c:571 __irq_exit_rcu+0xec/0x170 kernel/softirq.c:650 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:113 [inline] RIP: 0010:acpi_idle_do_entry drivers/acpi/processor_idle.c:572 [inline] RIP: 0010:acpi_idle_enter+0x43d/0x800 drivers/acpi/processor_idle.c:709 Code: ff e8 c7 ec 38 f7 48 83 e3 08 44 8b 7c 24 04 0f 85 00 01 00 00 e8 b3 ab 3f f7 66 90 e8 ec e7 38 f7 0f 00 2d f5 0f c5 00 fb f4 <4c> 89 e3 48 c1 eb 03 42 80 3c 2b 00 74 08 4c 89 e7 e8 5d bd 8d f7 RSP: 0018:ffffffff8ca07b80 EFLAGS: 000002d3 RAX: ffffffff8a50be24 RBX: 0000000000000000 RCX: ffffffff8cabb7c0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8a50be1d RBP: ffffffff8ca07c30 R08: ffffffff8a50be09 R09: fffffbfff19576f9 R10: fffffbfff19576f9 R11: 1ffffffff19576f8 R12: ffffffff8ca07bc0 R13: dffffc0000000000 R14: ffff888140a1b000 R15: 0000000000000001 cpuidle_enter_state+0x50b/0xf50 drivers/cpuidle/cpuidle.c:239 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:356 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x3da/0x680 kernel/sched/idle.c:303 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:400 rest_init+0x24f/0x270 init/main.c:729 arch_call_rest_init+0xa/0xa init/main.c:890 start_kernel+0x4b6/0x565 init/main.c:1145 secondary_startup_64_no_verify+0xcf/0xdb Allocated by task 3638: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:325 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:737 [inline] slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x1cc/0x300 mm/slub.c:3422 kmem_cache_zalloc include/linux/slab.h:702 [inline] net_alloc net/core/net_namespace.c:410 [inline] copy_net_ns+0x13c/0x5b0 net/core/net_namespace.c:465 create_new_namespaces+0x4db/0x8e0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11e/0x180 kernel/nsproxy.c:226 ksys_unshare+0x57f/0xb30 kernel/fork.c:3188 __do_sys_unshare kernel/fork.c:3259 [inline] __se_sys_unshare kernel/fork.c:3257 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3257 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:481 insert_work+0x54/0x3e0 kernel/workqueue.c:1358 __queue_work+0xaaa/0xd60 kernel/workqueue.c:1517 call_timer_fn+0xf5/0x210 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1514 [inline] __run_timers+0x7a2/0x980 kernel/time/timer.c:1790 __do_softirq+0x277/0x75b kernel/softirq.c:571 Second to last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:481 insert_work+0x54/0x3e0 kernel/workqueue.c:1358 __queue_work+0xaaa/0xd60 kernel/workqueue.c:1517 call_timer_fn+0xf5/0x210 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1514 [inline] __run_timers+0x7a2/0x980 kernel/time/timer.c:1790 __do_softirq+0x277/0x75b kernel/softirq.c:571 The buggy address belongs to the object at ffff88807be13880 which belongs to the cache net_namespace of size 6976 The buggy address is located 1861 bytes inside of 6976-byte region [ffff88807be13880, ffff88807be153c0) The buggy address belongs to the physical page: page:ffffea0001ef8400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807be154c0 pfn:0x7be10 head:ffffea0001ef8400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001e5c800 dead000000000002 ffff8880121d5640 raw: ffff88807be154c0 0000000080040000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3639, tgid 3639 (syz-executor.1), ts 181509965076, free_ts 181509189945 prep_new_page mm/page_alloc.c:2538 [inline] get_page_from_freelist+0x72b/0x7a0 mm/page_alloc.c:4287 __alloc_pages+0x259/0x560 mm/page_alloc.c:5554 alloc_slab_page+0x70/0xf0 mm/slub.c:1794 allocate_slab+0x5e/0x4b0 mm/slub.c:1939 new_slab mm/slub.c:1992 [inline] ___slab_alloc+0x7f4/0xeb0 mm/slub.c:3180 __slab_alloc mm/slub.c:3279 [inline] slab_alloc_node mm/slub.c:3364 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x24c/0x300 mm/slub.c:3422 kmem_cache_zalloc include/linux/slab.h:702 [inline] net_alloc net/core/net_namespace.c:410 [inline] copy_net_ns+0x13c/0x5b0 net/core/net_namespace.c:465 create_new_namespaces+0x4db/0x8e0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11e/0x180 kernel/nsproxy.c:226 ksys_unshare+0x57f/0xb30 kernel/fork.c:3188 __do_sys_unshare kernel/fork.c:3259 [inline] __se_sys_unshare kernel/fork.c:3257 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3257 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1458 [inline] free_pcp_prepare+0x80c/0x8f0 mm/page_alloc.c:1508 free_unref_page_prepare mm/page_alloc.c:3386 [inline] free_unref_page+0x7d/0x630 mm/page_alloc.c:3482 free_large_kmalloc+0x10b/0x1a0 mm/slab_common.c:932 skb_free_head net/core/skbuff.c:760 [inline] skb_release_data+0x536/0x6d0 net/core/skbuff.c:789 skb_release_all net/core/skbuff.c:854 [inline] __kfree_skb+0x56/0x1d0 net/core/skbuff.c:868 netlink_recvmsg+0x5c1/0x10f0 net/netlink/af_netlink.c:1998 ____sys_recvmsg+0x285/0x530 ___sys_recvmsg net/socket.c:2743 [inline] __sys_recvmsg+0x294/0x390 net/socket.c:2773 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff88807be13e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807be13f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807be13f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807be14000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807be14080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: e8 c7 ec 38 f7 callq 0xf738eccc 5: 48 83 e3 08 and $0x8,%rbx 9: 44 8b 7c 24 04 mov 0x4(%rsp),%r15d e: 0f 85 00 01 00 00 jne 0x114 14: e8 b3 ab 3f f7 callq 0xf73fabcc 19: 66 90 xchg %ax,%ax 1b: e8 ec e7 38 f7 callq 0xf738e80c 20: 0f 00 2d f5 0f c5 00 verw 0xc50ff5(%rip) # 0xc5101c 27: fb sti 28: f4 hlt * 29: 4c 89 e3 mov %r12,%rbx <-- trapping instruction 2c: 48 c1 eb 03 shr $0x3,%rbx 30: 42 80 3c 2b 00 cmpb $0x0,(%rbx,%r13,1) 35: 74 08 je 0x3f 37: 4c 89 e7 mov %r12,%rdi 3a: e8 5d bd 8d f7 callq 0xf78dbd9c