syzbot


KASAN: slab-out-of-bounds Read in bitmap_ip_add
Status: fixed on 2020/03/25 19:36
Reported-by: syzbot+f3e96783d74ee8ea9aa3@syzkaller.appspotmail.com
Fix commit: 32c72165dbd0 netfilter: ipset: use bitmap infrastructure completely
First crash: 857d, last: 846d

Cause bisection: introduced by (bisect log) :
commit 751ad98d5f881df91ba47e013b82422912381e8e
Author: Marco Elver <elver@google.com>
Date: Fri Jul 12 03:54:00 2019 +0000

  asm-generic, x86: add bitops instrumentation for KASAN

Crash: KASAN: slab-out-of-bounds Read in bitmap_ip_add (log)
Repro: syz .config

Fix bisection: fixed by (bisect log) :
commit 32c72165dbd0e246e69d16a3ad348a4851afd415
Author: Kadlecsik Jรณzsef <kadlec@blackhole.kfki.hu>
Date: Sun Jan 19 21:06:49 2020 +0000

  netfilter: ipset: use bitmap infrastructure completely


Sample crash report:
==================================================================
BUG: KASAN: slab-out-of-bounds in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:110 [inline]
BUG: KASAN: slab-out-of-bounds in bitmap_ip_do_add net/netfilter/ipset/ip_set_bitmap_ip.c:83 [inline]
BUG: KASAN: slab-out-of-bounds in bitmap_ip_add+0xef/0xe60 net/netfilter/ipset/ip_set_bitmap_gen.h:136
Read of size 8 at addr ffff8880a6fac400 by task syz-executor.0/9657

CPU: 0 PID: 9657 Comm: syz-executor.0 Not tainted 5.5.0-rc6-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_ip_do_add net/netfilter/ipset/ip_set_bitmap_ip.c:83 [inline]
 bitmap_ip_add+0xef/0xe60 net/netfilter/ipset/ip_set_bitmap_gen.h:136
 bitmap_ip_uadt+0x73e/0xa10 net/netfilter/ipset/ip_set_bitmap_ip.c:186
 call_ad+0x1a0/0x5a0 net/netfilter/ipset/ip_set_core.c:1716
 ip_set_ad.isra.0+0x572/0xb20 net/netfilter/ipset/ip_set_core.c:1804
 ip_set_uadd+0x37/0x50 net/netfilter/ipset/ip_set_core.c:1829
 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+0x58c/0x7d0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:659
 ____sys_sendmsg+0x753/0x880 net/socket.c:2330
 ___sys_sendmsg+0x100/0x170 net/socket.c:2384
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2417
 __do_sys_sendmsg net/socket.c:2426 [inline]
 __se_sys_sendmsg net/socket.c:2424 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2424
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45b159
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fd1c3a14c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd1c3a156d4 RCX: 000000000045b159
RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000008dc R14: 00000000004ca08f R15: 000000000075bf2c

Allocated by task 9657:
 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_ip net/netfilter/ipset/ip_set_bitmap_ip.c:223 [inline]
 bitmap_ip_create+0x6ec/0xc20 net/netfilter/ipset/ip_set_bitmap_ip.c:327
 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+0x58c/0x7d0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:659
 ____sys_sendmsg+0x753/0x880 net/socket.c:2330
 ___sys_sendmsg+0x100/0x170 net/socket.c:2384
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2417
 __do_sys_sendmsg net/socket.c:2426 [inline]
 __se_sys_sendmsg net/socket.c:2424 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2424
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 9437:
 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
 tomoyo_find_next_domain+0x6e7/0x1f6c security/tomoyo/domain.c:878
 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:107 [inline]
 tomoyo_bprm_check_security+0x124/0x1a0 security/tomoyo/tomoyo.c:97
 security_bprm_check+0x63/0xb0 security/security.c:784
 search_binary_handler+0x71/0x570 fs/exec.c:1645
 exec_binprm fs/exec.c:1701 [inline]
 __do_execve_file.isra.0+0x1329/0x22b0 fs/exec.c:1821
 do_execveat_common fs/exec.c:1867 [inline]
 do_execve fs/exec.c:1884 [inline]
 __do_sys_execve fs/exec.c:1960 [inline]
 __se_sys_execve fs/exec.c:1955 [inline]
 __x64_sys_execve+0x8f/0xc0 fs/exec.c:1955
 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 ffff8880a6fac400
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
 32-byte region [ffff8880a6fac400, ffff8880a6fac420)
The buggy address belongs to the page:
page:ffffea00029beb00 refcount:1 mapcount:0 mapping:ffff8880aa4001c0 index:0xffff8880a6facfc1
raw: 00fffe0000000200 ffffea000278b788 ffffea0002996648 ffff8880aa4001c0
raw: ffff8880a6facfc1 ffff8880a6fac000 0000000100000034 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a6fac300: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8880a6fac380: 00 06 fc fc fc fc fc fc fb fb fb fb fc fc fc fc
>ffff8880a6fac400: 04 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc
                   ^
 ffff8880a6fac480: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8880a6fac500: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
==================================================================

Crashes (7):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce 2020/01/19 12:37 upstream 244dc2689085 bc8bc756 .config log report syz
ci-upstream-kasan-gce-root 2020/01/19 09:13 upstream 244dc2689085 bc8bc756 .config log report syz
ci-upstream-kasan-gce-smack-root 2020/01/19 01:47 upstream 244dc2689085 bc8bc756 .config log report syz
ci-upstream-kasan-gce-386 2020/01/19 07:08 upstream 244dc2689085 bc8bc756 .config log report syz
ci-upstream-net-this-kasan-gce 2020/01/19 07:31 net e02d9c4c68dc bc8bc756 .config log report syz
ci-upstream-linux-next-kasan-gce-root 2020/01/30 09:07 linux-next 2747d5fdab78 5ed23f9a .config log report syz
ci-upstream-kasan-gce 2020/01/22 11:39 upstream d96d875ef5dd 8eda0b95 .config log report