================================================================== BUG: KASAN: use-after-free in smc_fback_error_report+0x96/0xa0 net/smc/af_smc.c:664 Read of size 8 at addr ffff888023c85168 by task syz-executor.0/19945 CPU: 3 PID: 19945 Comm: syz-executor.0 Not tainted 5.17.0-rc4-syzkaller-00051-gc5d9ae265b10 #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.constprop.0.cold+0x8d/0x303 mm/kasan/report.c:255 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 smc_fback_error_report+0x96/0xa0 net/smc/af_smc.c:664 sk_error_report+0x35/0x310 net/core/sock.c:340 tcp_write_err net/ipv4/tcp_timer.c:71 [inline] tcp_probe_timer net/ipv4/tcp_timer.c:395 [inline] tcp_write_timer_handler+0x437/0xbc0 net/ipv4/tcp_timer.c:626 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+0x67c/0xa30 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __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:638 RIP: 0010:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5607 Code: 9d a5 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc90000817ab0 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000102f58 RCX: 14aa22b9e94f3f88 RDX: 1ffff110030ffd73 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8ffc6947 R10: fffffbfff1ff8d28 R11: 0000000000000001 R12: 0000000000000002 R13: 0000000000000000 R14: ffffffff8bb81860 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:694 [inline] inet_twsk_purge+0x117/0x7d0 net/ipv4/inet_timewait_sock.c:268 ops_exit_list+0x125/0x170 net/core/net_namespace.c:173 setup_net+0x77e/0xbb0 net/core/net_namespace.c:353 copy_net_ns+0x318/0x760 net/core/net_namespace.c:474 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:3048 __do_sys_unshare kernel/fork.c:3119 [inline] __se_sys_unshare kernel/fork.c:3117 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3117 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: 0033:0x7fc886ff2059 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:00007fc885925168 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fc887105100 RCX: 00007fc886ff2059 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 00007fc88704c08d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd02f1542f R14: 00007fc885925300 R15: 0000000000022000 The buggy address belongs to the page: page:ffffea00008f2140 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x23c85 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 ffffffff00ad0101 0000000000000000 raw: 0000000000000000 ffff888023c85000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 1, migratetype Unmovable, gfp_mask 0x2c2220(__GFP_HIGH|__GFP_ATOMIC|__GFP_NOWARN|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_THISNODE), pid 19073, ts 1023554245142, free_ts 1023787647485 prep_new_page mm/page_alloc.c:2434 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165 __alloc_pages_slowpath.constprop.0+0x2eb/0x20d0 mm/page_alloc.c:4934 __alloc_pages+0x412/0x500 mm/page_alloc.c:5402 __alloc_pages_node include/linux/gfp.h:572 [inline] kmem_getpages mm/slab.c:1378 [inline] cache_grow_begin+0x75/0x390 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] slab_alloc_node mm/slab.c:3241 [inline] kmem_cache_alloc_node_trace+0x49c/0x5b0 mm/slab.c:3609 __do_kmalloc_node mm/slab.c:3631 [inline] __kmalloc_node_track_caller+0x38/0x60 mm/slab.c:3646 kmalloc_reserve net/core/skbuff.c:354 [inline] __alloc_skb+0xde/0x340 net/core/skbuff.c:426 alloc_skb include/linux/skbuff.h:1158 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:745 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:802 [inline] nsim_dev_trap_report_work+0x29a/0xbc0 drivers/net/netdevsim/dev.c:843 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1352 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404 free_unref_page_prepare mm/page_alloc.c:3325 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3404 slab_destroy mm/slab.c:1630 [inline] slabs_destroy+0x89/0xc0 mm/slab.c:1650 cache_flusharray mm/slab.c:3410 [inline] ___cache_free+0x303/0x600 mm/slab.c:3472 qlink_free mm/kasan/quarantine.c:157 [inline] qlist_free_all+0x50/0x1a0 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:260 [inline] slab_post_alloc_hook mm/slab.h:732 [inline] slab_alloc_node mm/slab.c:3253 [inline] kmem_cache_alloc_node_trace+0x2ff/0x5b0 mm/slab.c:3609 kmalloc_node include/linux/slab.h:599 [inline] kzalloc_node include/linux/slab.h:726 [inline] alloc_worker+0x43/0x1c0 kernel/workqueue.c:1858 create_worker+0xd1/0x530 kernel/workqueue.c:1955 maybe_create_worker kernel/workqueue.c:2125 [inline] manage_workers kernel/workqueue.c:2177 [inline] worker_thread+0xaee/0x1110 kernel/workqueue.c:2426 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff888023c85000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888023c85080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888023c85100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888023c85180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888023c85200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== ---------------- Code disassembly (best guess): 0: 9d popfq 1: a5 movsl %ds:(%rsi),%es:(%rdi) 2: 7e 83 jle 0xffffff87 4: f8 clc 5: 01 0f add %ecx,(%rdi) 7: 85 b4 02 00 00 9c 58 test %esi,0x589c0000(%rdx,%rax,1) e: f6 c4 02 test $0x2,%ah 11: 0f 85 9f 02 00 00 jne 0x2b6 17: 48 83 7c 24 08 00 cmpq $0x0,0x8(%rsp) 1d: 74 01 je 0x20 1f: fb sti 20: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 27: fc ff df * 2a: 48 01 c3 add %rax,%rbx <-- trapping instruction 2d: 48 c7 03 00 00 00 00 movq $0x0,(%rbx) 34: 48 c7 43 08 00 00 00 movq $0x0,0x8(%rbx) 3b: 00 3c: 48 rex.W 3d: 8b .byte 0x8b 3e: 84 .byte 0x84 3f: 24 .byte 0x24