================================================================== BUG: KASAN: use-after-free in tipc_recvmsg+0xf77/0xf90 net/tipc/socket.c:1979 Read of size 4 at addr ffff8880389ed940 by task syz-executor.4/20260 CPU: 0 PID: 20260 Comm: syz-executor.4 Not tainted 5.14.0-rc2-next-20210723-syzkaller #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:105 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:256 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 tipc_recvmsg+0xf77/0xf90 net/tipc/socket.c:1979 sock_recvmsg_nosec net/socket.c:943 [inline] sock_recvmsg net/socket.c:961 [inline] sock_recvmsg net/socket.c:957 [inline] ____sys_recvmsg+0x2c4/0x600 net/socket.c:2611 ___sys_recvmsg+0x127/0x200 net/socket.c:2653 __sys_recvmsg+0xe2/0x1a0 net/socket.c:2683 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: 0033:0x4665e9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe5cf9d8188 EFLAGS: 00000246 ORIG_RAX: 000000000000002f RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9 RDX: 0000000000000000 RSI: 000000002000d480 RDI: 0000000000000004 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007ffdf819671f R14: 00007fe5cf9d8300 R15: 0000000000022000 Allocated by task 20274: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x84/0xa0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:2958 [inline] kmem_cache_alloc_node+0x266/0x3e0 mm/slub.c:2994 __alloc_skb+0x20b/0x340 net/core/skbuff.c:414 alloc_skb_fclone include/linux/skbuff.h:1162 [inline] tipc_buf_acquire+0x25/0xe0 net/tipc/msg.c:72 tipc_msg_build+0xf7/0x10a0 net/tipc/msg.c:386 __tipc_sendstream+0x6d0/0x1150 net/tipc/socket.c:1610 tipc_sendstream net/tipc/socket.c:1541 [inline] tipc_send_packet+0x67/0xa0 net/tipc/socket.c:1647 sock_sendmsg_nosec net/socket.c:703 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:723 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2392 ___sys_sendmsg+0xf3/0x170 net/socket.c:2446 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2475 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 20260: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xfb/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1627 [inline] slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1652 slab_free mm/slub.c:3212 [inline] kmem_cache_free+0x8e/0x5a0 mm/slub.c:3228 kfree_skbmem+0x166/0x1b0 net/core/skbuff.c:720 __kfree_skb net/core/skbuff.c:756 [inline] kfree_skb net/core/skbuff.c:773 [inline] kfree_skb+0x140/0x3f0 net/core/skbuff.c:767 tipc_recvmsg+0x70d/0xf90 net/tipc/socket.c:1977 sock_recvmsg_nosec net/socket.c:943 [inline] sock_recvmsg net/socket.c:961 [inline] sock_recvmsg net/socket.c:957 [inline] ____sys_recvmsg+0x2c4/0x600 net/socket.c:2611 ___sys_recvmsg+0x127/0x200 net/socket.c:2653 __sys_recvmsg+0xe2/0x1a0 net/socket.c:2683 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 The buggy address belongs to the object at ffff8880389ed900 which belongs to the cache skbuff_fclone_cache of size 472 The buggy address is located 64 bytes inside of 472-byte region [ffff8880389ed900, ffff8880389edad8) The buggy address belongs to the page: page:ffffea0000e27b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x389ec head:ffffea0000e27b00 order:1 compound_mapcount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00009ceb80 0000000900000009 ffff888011ea2b40 raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x52a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 10799, ts 640145665257, free_ts 530205361980 prep_new_page mm/page_alloc.c:2424 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4152 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5374 alloc_pages+0x1a3/0x2d0 mm/mempolicy.c:2278 alloc_slab_page mm/slub.c:1690 [inline] allocate_slab+0x32e/0x4b0 mm/slub.c:1830 new_slab mm/slub.c:1893 [inline] new_slab_objects mm/slub.c:2639 [inline] ___slab_alloc+0x4ba/0x820 mm/slub.c:2802 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2842 slab_alloc_node mm/slub.c:2924 [inline] kmem_cache_alloc_node+0x12c/0x3e0 mm/slub.c:2994 __alloc_skb+0x20b/0x340 net/core/skbuff.c:414 alloc_skb_fclone include/linux/skbuff.h:1162 [inline] tipc_buf_acquire+0x25/0xe0 net/tipc/msg.c:72 tipc_msg_create+0x32/0x1f0 net/tipc/msg.c:104 __tipc_shutdown+0xb7f/0xe90 net/tipc/socket.c:591 tipc_release+0x13f/0x1a80 net/tipc/socket.c:640 __sock_release+0xcd/0x280 net/socket.c:648 sock_close+0x18/0x20 net/socket.c:1300 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1338 [inline] free_pcp_prepare+0x373/0x860 mm/page_alloc.c:1389 free_unref_page_prepare mm/page_alloc.c:3315 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3394 __vunmap+0x783/0xb70 mm/vmalloc.c:2609 __vfree+0x3c/0xd0 mm/vmalloc.c:2657 vfree+0x5a/0x90 mm/vmalloc.c:2688 __do_replace+0x16b/0x870 net/ipv4/netfilter/ip_tables.c:1099 do_replace net/ipv4/netfilter/ip_tables.c:1139 [inline] do_ipt_set_ctl+0x901/0xb80 net/ipv4/netfilter/ip_tables.c:1629 nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101 ip_setsockopt+0x3c3/0x3a60 net/ipv4/ip_sockglue.c:1435 tcp_setsockopt+0x136/0x24a0 net/ipv4/tcp.c:3657 __sys_setsockopt+0x2db/0x610 net/socket.c:2159 __do_sys_setsockopt net/socket.c:2170 [inline] __se_sys_setsockopt net/socket.c:2167 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2167 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: ffff8880389ed800: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ffff8880389ed880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880389ed900: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880389ed980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880389eda00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================