================================================================== BUG: KASAN: use-after-free in tcp_retransmit_timer+0x2ef3/0x3360 net/ipv4/tcp_timer.c:511 Read of size 8 at addr ffff88807aab02c0 by task syz-executor.1/17546 CPU: 0 PID: 17546 Comm: syz-executor.1 Not tainted 5.18.0-rc3-syzkaller-01616-g834650b50ed2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x495 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 tcp_retransmit_timer+0x2ef3/0x3360 net/ipv4/tcp_timer.c:511 tcp_write_timer_handler+0x5e6/0xbc0 net/ipv4/tcp_timer.c:622 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:642 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x679/0xa80 kernel/time/timer.c:1737 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1750 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:finish_task_switch.isra.0+0x323/0xb80 kernel/sched/core.c:4953 Code: a3 6e 1c 08 85 c0 75 02 0f 0b 48 85 db 0f 85 25 01 00 00 4c 89 f7 e8 fc f7 ff ff e8 a7 c4 2d 00 fb 65 48 8b 1c 25 00 70 02 00 <48> 8d bb 80 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 RSP: 0018:ffffc90008ac7240 EFLAGS: 00000206 RAX: 0000000000001a47 RBX: ffff888064621d00 RCX: 1ffffffff201596e RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90008ac7288 R08: 0000000000000001 R09: ffffffff90075957 R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880b9c3ad58 R13: ffff888076e4d700 R14: ffff8880b9c3a000 R15: ffff8880b9c3aa38 context_switch kernel/sched/core.c:5076 [inline] __schedule+0xaa2/0x4cc0 kernel/sched/core.c:6388 schedule+0xd2/0x1f0 kernel/sched/core.c:6460 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6519 __mutex_lock_common kernel/locking/mutex.c:673 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733 ovs_ct_limit_set_zone_limit net/openvswitch/conntrack.c:1990 [inline] ovs_ct_limit_cmd_set+0x45e/0xc70 net/openvswitch/conntrack.c:2159 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:731 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline] genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:792 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2502 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:725 ____sys_sendmsg+0x6e2/0x800 net/socket.c:2413 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2496 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+0x44/0xae RIP: 0033:0x7fb0036890e9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb0025fe168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fb00379bf60 RCX: 00007fb0036890e9 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 00007fb0036e308d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe116b836f R14: 00007fb0025fe300 R15: 0000000000022000 Allocated by task 17306: 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:436 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:469 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:749 [inline] slab_alloc_node mm/slub.c:3217 [inline] slab_alloc mm/slub.c:3225 [inline] __kmem_cache_alloc_lru mm/slub.c:3232 [inline] kmem_cache_alloc+0x204/0x3b0 mm/slub.c:3242 kmem_cache_zalloc include/linux/slab.h:704 [inline] net_alloc net/core/net_namespace.c:403 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:458 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x2f79/0x6fe0 kernel/fork.c:2237 kernel_clone+0xe7/0xab0 kernel/fork.c:2639 __do_sys_clone+0xc8/0x110 kernel/fork.c:2756 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+0x44/0xae Freed by task 17306: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x166/0x1a0 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3510 [inline] kmem_cache_free+0xdd/0x5a0 mm/slub.c:3527 net_free net/core/net_namespace.c:432 [inline] net_free net/core/net_namespace.c:428 [inline] copy_net_ns+0x590/0x760 net/core/net_namespace.c:481 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x2f79/0x6fe0 kernel/fork.c:2237 kernel_clone+0xe7/0xab0 kernel/fork.c:2639 __do_sys_clone+0xc8/0x110 kernel/fork.c:2756 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+0x44/0xae Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 insert_work+0x48/0x350 kernel/workqueue.c:1358 __queue_work+0x62e/0x1140 kernel/workqueue.c:1517 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1461 [inline] __run_timers.part.0+0x4a3/0xa80 kernel/time/timer.c:1737 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0x152/0x1d0 kernel/time/timer.c:1752 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 insert_work+0x48/0x350 kernel/workqueue.c:1358 __queue_work+0x62e/0x1140 kernel/workqueue.c:1517 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1461 [inline] __run_timers.part.0+0x4a3/0xa80 kernel/time/timer.c:1737 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0x152/0x1d0 kernel/time/timer.c:1752 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 The buggy address belongs to the object at ffff88807aab0000 which belongs to the cache net_namespace of size 6784 The buggy address is located 704 bytes inside of 6784-byte region [ffff88807aab0000, ffff88807aab1a80) The buggy address belongs to the physical page: page:ffffea0001eaac00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807aab1b80 pfn:0x7aab0 head:ffffea0001eaac00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff888062074181 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888010dcd3c0 raw: ffff88807aab1b80 0000000080040003 00000001ffffffff ffff888062074181 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4339, tgid 4337 (syz-executor.2), ts 129573888260, free_ts 129496584806 prep_new_page mm/page_alloc.c:2441 [inline] get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4182 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2272 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1944 new_slab mm/slub.c:2004 [inline] ___slab_alloc+0x8df/0xf20 mm/slub.c:3005 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3092 slab_alloc_node mm/slub.c:3183 [inline] slab_alloc mm/slub.c:3225 [inline] __kmem_cache_alloc_lru mm/slub.c:3232 [inline] kmem_cache_alloc+0x360/0x3b0 mm/slub.c:3242 kmem_cache_zalloc include/linux/slab.h:704 [inline] net_alloc net/core/net_namespace.c:403 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:458 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x2f79/0x6fe0 kernel/fork.c:2237 kernel_clone+0xe7/0xab0 kernel/fork.c:2639 __do_sys_clone+0xc8/0x110 kernel/fork.c:2756 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+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1356 [inline] free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1406 free_unref_page_prepare mm/page_alloc.c:3328 [inline] free_unref_page+0x19/0x6a0 mm/page_alloc.c:3423 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2523 qlink_free mm/kasan/quarantine.c:157 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:446 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:749 [inline] slab_alloc_node mm/slub.c:3217 [inline] slab_alloc mm/slub.c:3225 [inline] __kmalloc+0x200/0x350 mm/slub.c:4410 kmalloc include/linux/slab.h:586 [inline] kzalloc include/linux/slab.h:714 [inline] tomoyo_encode2.part.0+0xe9/0x3a0 security/tomoyo/realpath.c:45 tomoyo_encode2 security/tomoyo/realpath.c:31 [inline] tomoyo_encode+0x28/0x50 security/tomoyo/realpath.c:80 tomoyo_path_perm+0x368/0x400 security/tomoyo/file.c:831 tomoyo_path_symlink+0x94/0xe0 security/tomoyo/tomoyo.c:199 security_path_symlink+0xdf/0x150 security/security.c:1181 do_symlinkat+0x106/0x2e0 fs/namei.c:4321 __do_sys_symlinkat fs/namei.c:4343 [inline] __se_sys_symlinkat fs/namei.c:4340 [inline] __x64_sys_symlinkat+0x93/0xc0 fs/namei.c:4340 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+0x44/0xae Memory state around the buggy address: ffff88807aab0180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807aab0200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807aab0280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807aab0300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807aab0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: a3 6e 1c 08 85 c0 75 movabs %eax,0xf0275c085081c6e 7: 02 0f 9: 0b 48 85 or -0x7b(%rax),%ecx c: db 0f fisttpl (%rdi) e: 85 25 01 00 00 4c test %esp,0x4c000001(%rip) # 0x4c000015 14: 89 f7 mov %esi,%edi 16: e8 fc f7 ff ff callq 0xfffff817 1b: e8 a7 c4 2d 00 callq 0x2dc4c7 20: fb sti 21: 65 48 8b 1c 25 00 70 mov %gs:0x27000,%rbx 28: 02 00 * 2a: 48 8d bb 80 15 00 00 lea 0x1580(%rbx),%rdi <-- trapping instruction 31: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 38: fc ff df 3b: 48 89 fa mov %rdi,%rdx 3e: 48 rex.W 3f: c1 .byte 0xc1