================================================================== BUG: KASAN: slab-use-after-free in sk_fullsock include/net/sock.h:2823 [inline] BUG: KASAN: slab-use-after-free in ip_skb_dst_mtu+0x820/0x9a0 include/net/ip.h:499 Read of size 1 at addr ffff8880760be012 by task syz-executor.0/5357 CPU: 0 PID: 5357 Comm: syz-executor.0 Not tainted 6.8.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0x163/0x540 mm/kasan/report.c:488 kasan_report+0x142/0x170 mm/kasan/report.c:601 sk_fullsock include/net/sock.h:2823 [inline] ip_skb_dst_mtu+0x820/0x9a0 include/net/ip.h:499 __ip_finish_output+0x133/0x4b0 net/ipv4/ip_output.c:306 ipvlan_process_v4_outbound+0x3ef/0x700 drivers/net/ipvlan/ipvlan_core.c:442 ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:540 [inline] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] ipvlan_queue_xmit+0xa64/0x1170 drivers/net/ipvlan/ipvlan_core.c:668 ipvlan_start_xmit+0x4a/0x150 drivers/net/ipvlan/ipvlan_main.c:222 __netdev_start_xmit include/linux/netdevice.h:4989 [inline] netdev_start_xmit include/linux/netdevice.h:5003 [inline] xmit_one net/core/dev.c:3547 [inline] dev_hard_start_xmit+0x23e/0x750 net/core/dev.c:3563 sch_direct_xmit+0x2b6/0x5f0 net/sched/sch_generic.c:342 qdisc_restart net/sched/sch_generic.c:407 [inline] __qdisc_run+0xae1/0x1eb0 net/sched/sch_generic.c:415 qdisc_run+0xda/0x260 include/net/pkt_sched.h:125 net_tx_action+0x86f/0xa20 net/core/dev.c:5197 __do_softirq+0x2bf/0x93a kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu+0xf1/0x1b0 kernel/softirq.c:632 irq_exit_rcu+0x9/0x20 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 be 1c fc f6 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 d3 49 71 f6 65 8b 05 04 f4 14 75 85 c0 74 3f 48 c7 04 24 0e 36 RSP: 0018:ffffc90004d27be0 EFLAGS: 00000206 RAX: fea5525bf8b65a00 RBX: 1ffff920009a4f80 RCX: ffffffff92127203 RDX: dffffc0000000000 RSI: ffffffff8b2a8140 RDI: 0000000000000001 RBP: ffffc90004d27c78 R08: ffffffff8ebc14ef R09: 1ffffffff1d7829d R10: dffffc0000000000 R11: fffffbfff1d7829e R12: dffffc0000000000 R13: 1ffff920009a4f7c R14: ffffc90004d27c00 R15: 0000000000000246 debug_timer_init kernel/time/timer.c:774 [inline] debug_init kernel/time/timer.c:822 [inline] init_timer_key+0x38/0x2e0 kernel/time/timer.c:866 inet_csk_init_xmit_timers+0x85/0xf0 net/ipv4/inet_connection_sock.c:757 tcp_init_xmit_timers+0x36/0xb0 net/ipv4/tcp_timer.c:857 tcp_init_sock+0x70/0x850 net/ipv4/tcp.c:419 tcp_v4_init_sock+0x21/0x70 net/ipv4/tcp_ipv4.c:2472 inet_create+0xb90/0xe70 net/ipv4/af_inet.c:385 __sock_create+0x48c/0x910 net/socket.c:1571 sock_create net/socket.c:1622 [inline] __sys_socket_create net/socket.c:1659 [inline] __sys_socket+0x14f/0x3b0 net/socket.c:1706 __do_sys_socket net/socket.c:1720 [inline] __se_sys_socket net/socket.c:1718 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1718 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x85/0x160 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f615fe7fb27 Code: f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 b8 29 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc469b90d8 EFLAGS: 00000202 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f615fe7fb27 RDX: 0000000000000006 RSI: 0000000000000001 RDI: 0000000000000002 RBP: 00007ffc469b97ec R08: 00007ffc469b90cc R09: 00007ffc469b94d7 R10: 00007ffc469b9150 R11: 0000000000000202 R12: 0000000000000032 R13: 000000000001525d R14: 000000000001522c R15: 000000000000000b Allocated by task 5540: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x70 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:372 [inline] __kasan_kmalloc+0x7d/0x90 mm/kasan/common.c:389 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slub.c:3981 [inline] __kmalloc+0x224/0x500 mm/slub.c:3994 kmalloc include/linux/slab.h:594 [inline] sk_prot_alloc+0xe0/0x210 net/core/sock.c:2078 sk_alloc+0x39/0x310 net/core/sock.c:2131 packet_create+0x104/0x790 net/packet/af_packet.c:3352 __sock_create+0x48c/0x910 net/socket.c:1571 sock_create net/socket.c:1622 [inline] __sys_socket_create net/socket.c:1659 [inline] __sys_socket+0x14f/0x3b0 net/socket.c:1706 __do_sys_socket net/socket.c:1720 [inline] __se_sys_socket net/socket.c:1718 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1718 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x85/0x160 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Freed by task 5357: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x70 mm/kasan/common.c:68 kasan_save_free_info+0x4e/0x60 mm/kasan/generic.c:643 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:241 __kasan_slab_free+0x13/0x40 mm/kasan/common.c:257 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2121 [inline] slab_free mm/slub.c:4299 [inline] kfree+0x12b/0x340 mm/slub.c:4409 sk_prot_free net/core/sock.c:2114 [inline] __sk_destruct+0x45c/0x5c0 net/core/sock.c:2206 skb_orphan include/linux/skbuff.h:3127 [inline] ip_defrag+0x205/0x25c0 net/ipv4/ip_fragment.c:490 nf_ct_ipv4_gather_frags net/ipv4/netfilter/nf_defrag_ipv4.c:32 [inline] ipv4_conntrack_defrag+0x3de/0x590 net/ipv4/netfilter/nf_defrag_ipv4.c:87 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xbf/0x210 net/netfilter/core.c:626 nf_hook+0x2c4/0x450 include/linux/netfilter.h:269 __ip_local_out+0x3ca/0x4d0 net/ipv4/ip_output.c:118 ip_local_out+0x2a/0x130 net/ipv4/ip_output.c:127 ipvlan_process_v4_outbound+0x3ef/0x700 drivers/net/ipvlan/ipvlan_core.c:442 ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:540 [inline] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] ipvlan_queue_xmit+0xa64/0x1170 drivers/net/ipvlan/ipvlan_core.c:668 ipvlan_start_xmit+0x4a/0x150 drivers/net/ipvlan/ipvlan_main.c:222 __netdev_start_xmit include/linux/netdevice.h:4989 [inline] netdev_start_xmit include/linux/netdevice.h:5003 [inline] xmit_one net/core/dev.c:3547 [inline] dev_hard_start_xmit+0x23e/0x750 net/core/dev.c:3563 sch_direct_xmit+0x2b6/0x5f0 net/sched/sch_generic.c:342 qdisc_restart net/sched/sch_generic.c:407 [inline] __qdisc_run+0xae1/0x1eb0 net/sched/sch_generic.c:415 qdisc_run+0xda/0x260 include/net/pkt_sched.h:125 net_tx_action+0x86f/0xa20 net/core/dev.c:5197 __do_softirq+0x2bf/0x93a kernel/softirq.c:553 The buggy address belongs to the object at ffff8880760be000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 18 bytes inside of freed 4096-byte region [ffff8880760be000, ffff8880760bf000) The buggy address belongs to the physical page: page:ffffea0001d82e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x760b8 head:ffffea0001d82e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888012842140 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000040004 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4459, tgid 4459 (udevadm), ts 21156280721, free_ts 18960881125 prep_new_page mm/page_alloc.c:1540 [inline] get_page_from_freelist+0x339a/0x3530 mm/page_alloc.c:3311 __alloc_pages+0x255/0x670 mm/page_alloc.c:4567 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x150 mm/slub.c:2190 allocate_slab mm/slub.c:2354 [inline] new_slab+0x84/0x2f0 mm/slub.c:2407 ___slab_alloc+0xcf5/0x13b0 mm/slub.c:3540 __slab_alloc mm/slub.c:3625 [inline] __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] __do_kmalloc_node mm/slub.c:3980 [inline] __kmalloc+0x2ef/0x500 mm/slub.c:3994 kmalloc include/linux/slab.h:594 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x2b7/0x730 security/tomoyo/file.c:822 security_inode_getattr+0xd3/0x120 security/security.c:2238 vfs_getattr+0x46/0x430 fs/stat.c:173 vfs_statx+0x1a5/0x4e0 fs/stat.c:248 vfs_fstatat+0x135/0x190 fs/stat.c:304 __do_sys_newfstatat fs/stat.c:468 [inline] __se_sys_newfstatat fs/stat.c:462 [inline] __x64_sys_newfstatat+0x117/0x190 fs/stat.c:462 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x85/0x160 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1140 [inline] free_unref_page_prepare+0x94d/0xa60 mm/page_alloc.c:2346 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486 free_contig_range+0x9e/0x150 mm/page_alloc.c:6535 destroy_args+0x8a/0x880 mm/debug_vm_pgtable.c:1028 debug_vm_pgtable+0x4ba/0x540 mm/debug_vm_pgtable.c:1408 do_one_initcall+0x234/0x800 init/main.c:1236 do_initcall_level+0x157/0x210 init/main.c:1298 do_initcalls+0x3f/0x80 init/main.c:1314 kernel_init_freeable+0x429/0x5c0 init/main.c:1551 kernel_init+0x1d/0x2a0 init/main.c:1441 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Memory state around the buggy address: ffff8880760bdf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880760bdf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880760be000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880760be080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880760be100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 9c pushf 1: 8f 44 24 20 pop 0x20(%rsp) 5: 42 80 3c 23 00 cmpb $0x0,(%rbx,%r12,1) a: 74 08 je 0x14 c: 4c 89 f7 mov %r14,%rdi f: e8 be 1c fc f6 call 0xf6fc1cd2 14: f6 44 24 21 02 testb $0x2,0x21(%rsp) 19: 75 4e jne 0x69 1b: 41 f7 c7 00 02 00 00 test $0x200,%r15d 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 d3 49 71 f6 call 0xf6714a02 <-- trapping instruction 2f: 65 8b 05 04 f4 14 75 mov %gs:0x7514f404(%rip),%eax # 0x7514f43a 36: 85 c0 test %eax,%eax 38: 74 3f je 0x79 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss