================================================================== BUG: KASAN: slab-out-of-bounds in string+0x1e8/0x200 lib/vsprintf.c:592 Read of size 1 at addr ffff8801cc85a8b8 by task syz-executor6/5797 CPU: 1 PID: 5797 Comm: syz-executor6 Not tainted 4.9.78-g29eadc4 #29 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801afe2f5d0 ffffffff81d943a9 ffffea0007321680 ffff8801cc85a8b8 0000000000000000 ffff8801cc85a8b8 ffff8801afe2f82c ffff8801afe2f608 ffffffff8153dc23 ffff8801cc85a8b8 0000000000000001 0000000000000000 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] print_address_description+0x73/0x280 mm/kasan/report.c:252 [] kasan_report_error mm/kasan/report.c:351 [inline] [] kasan_report+0x275/0x360 mm/kasan/report.c:408 [] __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:426 [] string+0x1e8/0x200 lib/vsprintf.c:592 [] vsnprintf+0x7ad/0x16d0 lib/vsprintf.c:2044 [] __request_module+0x14f/0x750 kernel/kmod.c:146 [] xt_request_find_target+0x8b/0xb0 net/netfilter/x_tables.c:256 [] check_compat_entry_size_and_hooks net/ipv4/netfilter/ip_tables.c:1342 [inline] [] translate_compat_table+0x568/0x1760 net/ipv4/netfilter/ip_tables.c:1431 [] ? 0xffffffff810002b8 [] compat_do_replace.isra.15+0x1a7/0x3a0 net/ipv4/netfilter/ip_tables.c:1534 [] compat_do_ipt_set_ctl+0x106/0x150 net/ipv4/netfilter/ip_tables.c:1563 [] compat_nf_sockopt net/netfilter/nf_sockopt.c:143 [inline] [] compat_nf_setsockopt+0x88/0x130 net/netfilter/nf_sockopt.c:155 [] compat_ip_setsockopt+0x9d/0xf0 net/ipv4/ip_sockglue.c:1277 [] inet_csk_compat_setsockopt+0x95/0x120 net/ipv4/inet_connection_sock.c:914 [] compat_tcp_setsockopt+0x3d/0x70 net/ipv4/tcp.c:2748 [] compat_sock_common_setsockopt+0xb2/0x140 net/core/sock.c:2717 [] C_SYSC_setsockopt net/compat.c:398 [inline] [] compat_SyS_setsockopt+0x149/0x290 net/compat.c:381 [] do_syscall_32_irqs_on arch/x86/entry/common.c:322 [inline] [] do_fast_syscall_32+0x2f7/0x890 arch/x86/entry/common.c:384 [] entry_SYSENTER_compat+0x74/0x83 arch/x86/entry/entry_64_compat.S:127 Allocated by task 5797: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 save_stack+0x43/0xd0 mm/kasan/kasan.c:505 set_track mm/kasan/kasan.c:517 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:609 __kmalloc+0x11d/0x310 mm/slub.c:3741 kmalloc include/linux/slab.h:495 [inline] xt_alloc_table_info+0x71/0x100 net/netfilter/x_tables.c:959 compat_do_replace.isra.15+0x116/0x3a0 net/ipv4/netfilter/ip_tables.c:1523 compat_do_ipt_set_ctl+0x106/0x150 net/ipv4/netfilter/ip_tables.c:1563 compat_nf_sockopt net/netfilter/nf_sockopt.c:143 [inline] compat_nf_setsockopt+0x88/0x130 net/netfilter/nf_sockopt.c:155 compat_ip_setsockopt+0x9d/0xf0 net/ipv4/ip_sockglue.c:1277 inet_csk_compat_setsockopt+0x95/0x120 net/ipv4/inet_connection_sock.c:914 compat_tcp_setsockopt+0x3d/0x70 net/ipv4/tcp.c:2748 compat_sock_common_setsockopt+0xb2/0x140 net/core/sock.c:2717 C_SYSC_setsockopt net/compat.c:398 [inline] compat_SyS_setsockopt+0x149/0x290 net/compat.c:381 do_syscall_32_irqs_on arch/x86/entry/common.c:322 [inline] do_fast_syscall_32+0x2f7/0x890 arch/x86/entry/common.c:384 entry_SYSENTER_compat+0x74/0x83 arch/x86/entry/entry_64_compat.S:127 Freed by task 3311: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 save_stack+0x43/0xd0 mm/kasan/kasan.c:505 set_track mm/kasan/kasan.c:517 [inline] kasan_slab_free+0x72/0xc0 mm/kasan/kasan.c:582 slab_free_hook mm/slub.c:1355 [inline] slab_free_freelist_hook mm/slub.c:1377 [inline] slab_free mm/slub.c:2958 [inline] kfree+0x103/0x300 mm/slub.c:3878 skb_free_head+0x74/0xb0 net/core/skbuff.c:580 skb_release_data+0x315/0x3f0 net/core/skbuff.c:611 skb_release_all+0x4a/0x60 net/core/skbuff.c:670 __kfree_skb net/core/skbuff.c:684 [inline] consume_skb+0xc6/0x340 net/core/skbuff.c:757 unix_stream_read_generic+0x15f4/0x1d50 net/unix/af_unix.c:2432 unix_stream_recvmsg+0xc1/0x100 net/unix/af_unix.c:2490 sock_recvmsg_nosec net/socket.c:737 [inline] sock_recvmsg+0xc9/0x110 net/socket.c:744 sock_read_iter+0x255/0x370 net/socket.c:821 new_sync_read fs/read_write.c:442 [inline] __vfs_read+0x4bc/0x670 fs/read_write.c:454 vfs_read+0x11e/0x380 fs/read_write.c:475 SYSC_read fs/read_write.c:591 [inline] SyS_read+0xd9/0x1b0 fs/read_write.c:584 entry_SYSCALL_64_fastpath+0x29/0xe8 The buggy address belongs to the object at ffff8801cc85a780 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 312 bytes inside of 512-byte region [ffff8801cc85a780, ffff8801cc85a980) The buggy address belongs to the page: page:ffffea0007321680 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 flags: 0x8000000000004080(slab|head) page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801cc85a780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801cc85a800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8801cc85a880: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ^ ffff8801cc85a900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801cc85a980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== binder: release 5832:5835 transaction 6 out, still active