Hello, syzbot found the following crash on: HEAD commit: 7f013ede Merge git://git.kernel.org/pub/scm/linux/kernel/g.. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=11c41495e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=66d8660c57ff3c98 dashboard link: https://syzkaller.appspot.com/bug?extid=33fc3ad6fa11675e1a7e compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15102cc9e00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17e38faee00000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+33fc3ad6fa11675e1a7e@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: use-after-free in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline] BUG: KASAN: use-after-free in bitmap_ipmac_ext_cleanup+0xd8/0x290 net/netfilter/ipset/ip_set_bitmap_gen.h:51 Read of size 8 at addr ffff8880a2ac3a40 by task syz-executor324/9651 CPU: 0 PID: 9651 Comm: syz-executor324 Not tainted 5.5.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:639 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192 __kasan_check_read+0x11/0x20 mm/kasan/common.c:95 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline] bitmap_ipmac_ext_cleanup+0xd8/0x290 net/netfilter/ipset/ip_set_bitmap_gen.h:51 bitmap_ipmac_destroy+0x17c/0x1d0 net/netfilter/ipset/ip_set_bitmap_gen.h:65 ip_set_create+0xe47/0x1500 net/netfilter/ipset/ip_set_core.c:1165 nfnetlink_rcv_msg+0xcf2/0xfb0 net/netfilter/nfnetlink.c:229 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 nfnetlink_rcv+0x1ba/0x460 net/netfilter/nfnetlink.c:563 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x442239 Code: e8 6c aa 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0f 83 9b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffc7958b8c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000442239 RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000000000000003 RBP: 0000000000016edc R08: 00000000004030f0 R09: 00000000004030f0 R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000403060 R13: 00000000004030f0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 9651: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:527 __do_kmalloc mm/slab.c:3656 [inline] __kmalloc+0x163/0x770 mm/slab.c:3665 kmalloc include/linux/slab.h:561 [inline] kzalloc include/linux/slab.h:670 [inline] ip_set_alloc+0x38/0x5e net/netfilter/ipset/ip_set_core.c:255 init_map_ipmac net/netfilter/ipset/ip_set_bitmap_ipmac.c:302 [inline] bitmap_ipmac_create+0x4e8/0xa00 net/netfilter/ipset/ip_set_bitmap_ipmac.c:365 ip_set_create+0x6f1/0x1500 net/netfilter/ipset/ip_set_core.c:1111 nfnetlink_rcv_msg+0xcf2/0xfb0 net/netfilter/nfnetlink.c:229 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 nfnetlink_rcv+0x1ba/0x460 net/netfilter/nfnetlink.c:563 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9651: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:335 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:474 kasan_slab_free+0xe/0x10 mm/kasan/common.c:483 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x2c0 mm/slab.c:3757 kvfree+0x61/0x70 mm/util.c:603 ip_set_free+0x16/0x20 net/netfilter/ipset/ip_set_core.c:276 bitmap_ipmac_destroy+0xae/0x1d0 net/netfilter/ipset/ip_set_bitmap_gen.h:63 ip_set_create+0xe47/0x1500 net/netfilter/ipset/ip_set_core.c:1165 nfnetlink_rcv_msg+0xcf2/0xfb0 net/netfilter/nfnetlink.c:229 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 nfnetlink_rcv+0x1ba/0x460 net/netfilter/nfnetlink.c:563 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a2ac3a40 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of 32-byte region [ffff8880a2ac3a40, ffff8880a2ac3a60) The buggy address belongs to the page: page:ffffea00028ab0c0 refcount:1 mapcount:0 mapping:ffff8880aa4001c0 index:0xffff8880a2ac3fc1 raw: 00fffe0000000200 ffffea000293f948 ffffea00025764c8 ffff8880aa4001c0 raw: ffff8880a2ac3fc1 ffff8880a2ac3000 000000010000003f 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a2ac3900: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ffff8880a2ac3980: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc >ffff8880a2ac3a00: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc ^ ffff8880a2ac3a80: fb fb fb fb fc fc fc fc 00 00 fc fc fc fc fc fc ffff8880a2ac3b00: fb fb fb fb fc fc fc fc 00 03 fc fc fc fc fc fc ================================================================== --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. syzbot can test patches for this bug, for details see: https://goo.gl/tpsmEJ#testing-patches
