================================================================== BUG: KASAN: use-after-free in tcp_retransmit_timer+0x2ef3/0x3360 net/ipv4/tcp_timer.c:511 Read of size 8 at addr ffff888020328380 by task udevd/4158 CPU: 1 PID: 4158 Comm: udevd Not tainted 5.18.0-rc3-syzkaller-00074-gb05a5683eba6-dirty #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/0x467 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:prefetchw arch/x86/include/asm/processor.h:743 [inline] RIP: 0010:slab_alloc mm/slab.c:3312 [inline] RIP: 0010:__do_kmalloc mm/slab.c:3708 [inline] RIP: 0010:__kmalloc+0x1af/0x4d0 mm/slab.c:3719 Code: 0f 84 46 01 00 00 4d 85 f6 48 89 54 24 18 0f 85 dd 01 00 00 9c 58 f6 c4 02 0f 85 fb 01 00 00 4d 85 f6 74 01 fb 48 8b 74 24 18 <0f> 0d 0e 0f 1f 44 00 00 48 83 7b 50 00 0f 84 85 00 00 00 44 8b 35 RSP: 0018:ffffc90003687738 EFLAGS: 00000206 RAX: 0000000000000006 RBX: ffff888010c40900 RCX: 1ffffffff1b6cca9 RDX: 0000000000000000 RSI: ffff88804483a000 RDI: 0000000000000000 RBP: 0000000000000c40 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff817e0cc8 R11: 0000000000000001 R12: 0000000000001000 R13: 0000000000000c40 R14: 0000000000000200 R15: 0000000000000000 kmalloc include/linux/slab.h:586 [inline] tomoyo_realpath_from_path+0xc3/0x620 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x272/0x380 security/tomoyo/file.c:771 tomoyo_file_open security/tomoyo/tomoyo.c:311 [inline] tomoyo_file_open+0x9d/0xc0 security/tomoyo/tomoyo.c:306 security_file_open+0x45/0xb0 security/security.c:1651 do_dentry_open+0x349/0x11e0 fs/open.c:811 do_open fs/namei.c:3476 [inline] path_openat+0x1c71/0x2910 fs/namei.c:3609 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4c0 fs/open.c:1213 do_sys_open fs/open.c:1229 [inline] __do_sys_openat fs/open.c:1245 [inline] __se_sys_openat fs/open.c:1240 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1240 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f05b0b25697 Code: 25 00 00 41 00 3d 00 00 41 00 74 37 64 8b 04 25 18 00 00 00 85 c0 75 5b 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 85 00 00 00 48 83 c4 68 5d 41 5c c3 0f 1f RSP: 002b:00007ffe2589e810 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000556cc6fd3150 RCX: 00007f05b0b25697 RDX: 0000000000080000 RSI: 0000556cc6f9d160 RDI: 00000000ffffff9c RBP: 0000556cc6f9d160 R08: 0000556cc6f9d160 R09: 00007f05b0bf5a60 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000 R13: 0000000000000705 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3894: 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+0x85/0xb0 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 mm/slab.c:3316 [inline] __kmem_cache_alloc_lru mm/slab.c:3493 [inline] kmem_cache_alloc+0x265/0x560 mm/slab.c:3513 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 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3132 __do_sys_unshare kernel/fork.c:3203 [inline] __se_sys_unshare kernel/fork.c:3201 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3201 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 50: 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+0x13d/0x180 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:200 [inline] __cache_free mm/slab.c:3439 [inline] kmem_cache_free.part.0+0xa9/0x240 mm/slab.c:3749 net_free net/core/net_namespace.c:432 [inline] net_free net/core/net_namespace.c:428 [inline] cleanup_net+0x8ba/0xb00 net/core/net_namespace.c:615 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 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+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+0x7e/0x90 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 ffff8880203280c0 which belongs to the cache net_namespace of size 6784 The buggy address is located 704 bytes inside of 6784-byte region [ffff8880203280c0, ffff888020329b40) The buggy address belongs to the physical page: page:ffffea000080ca00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20328 head:ffffea000080ca00 order:1 compound_mapcount:0 compound_pincount:0 memcg:ffff88801605c281 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00008ef008 ffffea0001f97108 ffff8880114d3600 raw: 0000000000000000 ffff8880203280c0 0000000100000001 ffff88801605c281 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x3420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 3894, tgid 3894 (syz-executor.3), ts 65729083336, free_ts 62504832892 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_node include/linux/gfp.h:587 [inline] kmem_getpages mm/slab.c:1378 [inline] cache_grow_begin+0x75/0x350 mm/slab.c:2584 cache_alloc_refill+0x27f/0x380 mm/slab.c:2957 ____cache_alloc mm/slab.c:3040 [inline] ____cache_alloc mm/slab.c:3023 [inline] __do_cache_alloc mm/slab.c:3267 [inline] slab_alloc mm/slab.c:3309 [inline] __kmem_cache_alloc_lru mm/slab.c:3493 [inline] kmem_cache_alloc+0x450/0x560 mm/slab.c:3513 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 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3132 __do_sys_unshare kernel/fork.c:3203 [inline] __se_sys_unshare kernel/fork.c:3201 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3201 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 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 slab_destroy mm/slab.c:1630 [inline] slabs_destroy+0x89/0xc0 mm/slab.c:1650 cache_flusharray mm/slab.c:3411 [inline] ___cache_free+0x34e/0x670 mm/slab.c:3474 qlink_free mm/kasan/quarantine.c:157 [inline] qlist_free_all+0x4f/0x1b0 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x97/0xb0 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/slab.c:3253 [inline] kmem_cache_alloc_node+0x2ea/0x590 mm/slab.c:3607 __alloc_skb+0x215/0x340 net/core/skbuff.c:414 alloc_skb include/linux/skbuff.h:1300 [inline] alloc_skb_with_frags+0x93/0x730 net/core/skbuff.c:5995 sock_alloc_send_pskb+0x793/0x920 net/core/sock.c:2600 unix_dgram_sendmsg+0x414/0x1a90 net/unix/af_unix.c:1896 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:725 sock_write_iter+0x283/0x3c0 net/socket.c:1061 call_write_iter include/linux/fs.h:2050 [inline] new_sync_write+0x38a/0x560 fs/read_write.c:504 vfs_write+0x7c0/0xac0 fs/read_write.c:591 Memory state around the buggy address: ffff888020328280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888020328300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888020328380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888020328400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888020328480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 0f 84 46 01 00 00 je 0x14c 6: 4d 85 f6 test %r14,%r14 9: 48 89 54 24 18 mov %rdx,0x18(%rsp) e: 0f 85 dd 01 00 00 jne 0x1f1 14: 9c pushfq 15: 58 pop %rax 16: f6 c4 02 test $0x2,%ah 19: 0f 85 fb 01 00 00 jne 0x21a 1f: 4d 85 f6 test %r14,%r14 22: 74 01 je 0x25 24: fb sti 25: 48 8b 74 24 18 mov 0x18(%rsp),%rsi * 2a: 0f 0d 0e prefetchw (%rsi) <-- trapping instruction 2d: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 32: 48 83 7b 50 00 cmpq $0x0,0x50(%rbx) 37: 0f 84 85 00 00 00 je 0xc2 3d: 44 rex.R 3e: 8b .byte 0x8b 3f: 35 .byte 0x35