================================================================== BUG: KASAN: use-after-free in tcp_or_dccp_get_hashinfo include/net/inet_hashtables.h:186 [inline] BUG: KASAN: use-after-free in reqsk_queue_unlink net/ipv4/inet_connection_sock.c:956 [inline] BUG: KASAN: use-after-free in inet_csk_reqsk_queue_drop+0xf3/0x3b0 net/ipv4/inet_connection_sock.c:970 Read of size 8 at addr ffff8880750dbd80 by task udevd/6972 CPU: 1 PID: 6972 Comm: udevd Not tainted 6.1.82-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15f/0x4f0 mm/kasan/report.c:395 kasan_report+0x136/0x160 mm/kasan/report.c:495 tcp_or_dccp_get_hashinfo include/net/inet_hashtables.h:186 [inline] reqsk_queue_unlink net/ipv4/inet_connection_sock.c:956 [inline] inet_csk_reqsk_queue_drop+0xf3/0x3b0 net/ipv4/inet_connection_sock.c:970 inet_csk_reqsk_queue_drop_and_put net/ipv4/inet_connection_sock.c:982 [inline] reqsk_timer_handler+0x90b/0xe70 net/ipv4/inet_connection_sock.c:1096 call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1790 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x155/0x240 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:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:__get_user_8+0x1b/0x30 arch/x86/lib/getuser.S:101 Code: 01 ca c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 ba f9 ef ff ff ff 7f 00 00 48 39 d0 73 64 48 19 d2 48 21 d0 0f 01 cb 48 8b 10 <31> c0 0f 01 ca c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 0f RSP: 0018:ffffc90003fc7d78 EFLAGS: 00040206 RAX: 00007fe4cb6e4628 RBX: ffffc90003fc7d80 RCX: ffffc90003fc7c03 RDX: 0000000000000000 RSI: ffffffff8aebffc0 RDI: ffffffff8b3d2b40 RBP: ffffc90003fc7ea8 R08: dffffc0000000000 R09: fffffbfff1ce6c56 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880214bd0e8 R13: dffffc0000000000 R14: 1ffff920007f8ffb R15: 0000000000000000 rseq_get_rseq_cs kernel/rseq.c:132 [inline] rseq_ip_fixup kernel/rseq.c:252 [inline] __rseq_handle_notify_resume+0x158/0x1500 kernel/rseq.c:300 rseq_handle_notify_resume include/linux/sched.h:2329 [inline] resume_user_mode_work include/linux/resume_user_mode.h:61 [inline] exit_to_user_mode_loop+0xb4/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:297 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fe4cb323457 Code: 73 01 c3 48 8b 0d d1 d9 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 e8 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 76 48 8b 15 a2 d9 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffd48359808 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 00007fe4cb323457 RDX: 0000000000000004 RSI: 00007ffd48359848 RDI: 0000000000000004 RBP: 000055ad8aae5cf0 R08: 0000000000000007 R09: 30369ce1c6984ff3 R10: 00000000ffffffff R11: 0000000000000246 R12: 000055ad8aaebe90 R13: 00007ffd48359848 R14: 0000000000000008 R15: 000055ad8aac4910 Allocated by task 7103: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 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+0x10c/0x2d0 mm/slub.c:3422 kmem_cache_zalloc include/linux/slab.h:682 [inline] net_alloc net/core/net_namespace.c:410 [inline] copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:465 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226 ksys_unshare+0x580/0xb20 kernel/fork.c:3203 __do_sys_unshare kernel/fork.c:3274 [inline] __se_sys_unshare kernel/fork.c:3272 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3272 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 4279: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] kmem_cache_free+0x292/0x510 mm/slub.c:3683 net_free net/core/net_namespace.c:439 [inline] cleanup_net+0xab5/0xb60 net/core/net_namespace.c:622 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307 The buggy address belongs to the object at ffff8880750db880 which belongs to the cache net_namespace of size 6976 The buggy address is located 1280 bytes inside of 6976-byte region [ffff8880750db880, ffff8880750dd3c0) The buggy address belongs to the physical page: page:ffffea0001d43600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880750d9c40 pfn:0x750d8 head:ffffea0001d43600 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888140009500 raw: ffff8880750d9c40 0000000080040003 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 3585, tgid 3585 (syz-executor.2), ts 160757873057, free_ts 159059909102 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2513 prep_new_page mm/page_alloc.c:2520 [inline] get_page_from_freelist+0x31a1/0x3320 mm/page_alloc.c:4279 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5545 alloc_slab_page+0x6a/0x150 mm/slub.c:1794 allocate_slab mm/slub.c:1939 [inline] new_slab+0x84/0x2d0 mm/slub.c:1992 ___slab_alloc+0xc20/0x1270 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+0x1a5/0x2d0 mm/slub.c:3422 kmem_cache_zalloc include/linux/slab.h:682 [inline] net_alloc net/core/net_namespace.c:410 [inline] copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:465 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226 ksys_unshare+0x580/0xb20 kernel/fork.c:3203 __do_sys_unshare kernel/fork.c:3274 [inline] __se_sys_unshare kernel/fork.c:3272 [inline] __x64_sys_unshare+0x34/0x40 kernel/fork.c:3272 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 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:1440 [inline] free_pcp_prepare mm/page_alloc.c:1490 [inline] free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3358 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3453 free_slab mm/slub.c:2031 [inline] discard_slab mm/slub.c:2037 [inline] __unfreeze_partials+0x1b7/0x210 mm/slub.c:2586 put_cpu_partial+0x17b/0x250 mm/slub.c:2662 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] kmem_cache_alloc_node+0x136/0x310 mm/slub.c:3443 __alloc_skb+0xde/0x670 net/core/skbuff.c:505 alloc_skb_fclone include/linux/skbuff.h:1326 [inline] tcp_stream_alloc_skb+0x3e/0x310 net/ipv4/tcp.c:868 tcp_sendmsg_locked+0xda6/0x4100 net/ipv4/tcp.c:1331 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1489 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] sock_write_iter+0x394/0x4e0 net/socket.c:1143 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x7ae/0xba0 fs/read_write.c:584 ksys_write+0x19c/0x2c0 fs/read_write.c:637 Memory state around the buggy address: ffff8880750dbc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880750dbd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880750dbd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880750dbe00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880750dbe80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 01 ca add %ecx,%edx 2: c3 ret 3: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) a: 00 00 00 d: 66 90 xchg %ax,%ax f: 48 ba f9 ef ff ff ff movabs $0x7fffffffeff9,%rdx 16: 7f 00 00 19: 48 39 d0 cmp %rdx,%rax 1c: 73 64 jae 0x82 1e: 48 19 d2 sbb %rdx,%rdx 21: 48 21 d0 and %rdx,%rax 24: 0f 01 cb stac 27: 48 8b 10 mov (%rax),%rdx * 2a: 31 c0 xor %eax,%eax <-- trapping instruction 2c: 0f 01 ca clac 2f: c3 ret 30: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 37: 00 00 00 3a: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 3f: 0f .byte 0xf