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KASAN: slab-out-of-bounds Read in bitmap_port_add

Status: fixed on 2020/02/18 14:31
Subsystems: netfilter
[Documentation on labels]
Reported-by: syzbot+dfccdb2bdb4a12ad425e@syzkaller.appspotmail.com
Fix commit: 32c72165dbd0 netfilter: ipset: use bitmap infrastructure completely
First crash: 1560d, last: 1553d
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_port_add (log)
Repro: syz .config
  
▶ ▼ Discussions (8)
Title Replies (including bot) Last reply
[PATCH 4.19 00/92] 4.19.100-stable review 98 (98) 2020/01/31 13:57
[PATCH 4.9 000/271] 4.9.212-stable review 283 (283) 2020/01/29 22:35
[PATCH 5.4 000/104] 5.4.16-stable review 113 (113) 2020/01/29 15:36
[PATCH 4.14 00/46] 4.14.169-stable review 51 (51) 2020/01/29 14:42
[PATCH 4.4 000/183] 4.4.212-stable review 190 (190) 2020/01/29 13:12
[PATCH 0/7] Netfilter fixes for net 9 (9) 2020/01/25 20:40
[PATCH 1/1] netfilter: ipset: use bitmap infrastructure completely 2 (2) 2020/01/20 16:42
KASAN: slab-out-of-bounds Read in bitmap_port_add 0 (1) 2020/01/18 07:57

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_port_do_add net/netfilter/ipset/ip_set_bitmap_port.c:74 [inline]
BUG: KASAN: slab-out-of-bounds in bitmap_port_add+0xef/0xe60 net/netfilter/ipset/ip_set_bitmap_gen.h:136
Read of size 8 at addr ffff888094d6e280 by task syz-executor.0/10694

CPU: 1 PID: 10694 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_port_do_add net/netfilter/ipset/ip_set_bitmap_port.c:74 [inline]
 bitmap_port_add+0xef/0xe60 net/netfilter/ipset/ip_set_bitmap_gen.h:136
 bitmap_port_uadt+0x65d/0x8a0 net/netfilter/ipset/ip_set_bitmap_port.c:199
 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: 0033:0x45aff9
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:00007fc902bb2c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fc902bb36d4 RCX: 000000000045aff9
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000008c8 R14: 00000000004c9dfc R15: 000000000075bf2c

Allocated by task 10690:
 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_port net/netfilter/ipset/ip_set_bitmap_port.c:234 [inline]
 bitmap_port_create+0x3dc/0x7c0 net/netfilter/ipset/ip_set_bitmap_port.c:276
 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 10472:
 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
 security_cred_free+0xa9/0x110 security/security.c:1548
 put_cred_rcu+0x129/0x4b0 kernel/cred.c:114
 __rcu_reclaim kernel/rcu/rcu.h:222 [inline]
 rcu_do_batch kernel/rcu/tree.c:2183 [inline]
 rcu_core+0x570/0x1540 kernel/rcu/tree.c:2408
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2417
 __do_softirq+0x262/0x98c kernel/softirq.c:292

The buggy address belongs to the object at ffff888094d6e280
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
 32-byte region [ffff888094d6e280, ffff888094d6e2a0)
The buggy address belongs to the page:
page:ffffea0002535b80 refcount:1 mapcount:0 mapping:ffff8880aa4001c0 index:0xffff888094d6efc1
raw: 00fffe0000000200 ffffea00028549c8 ffffea000287c348 ffff8880aa4001c0
raw: ffff888094d6efc1 ffff888094d6e000 000000010000003f 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888094d6e180: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff888094d6e200: fb fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc
>ffff888094d6e280: 04 fc fc fc fc fc fc fc 00 00 00 fc fc fc fc fc
                   ^
 ffff888094d6e300: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff888094d6e380: fb fb fb fb fc fc fc fc 00 00 01 fc fc fc fc fc
==================================================================

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/01/18 13:43 upstream 25e73aadf297 3de7aabb .config console log report syz ci-upstream-kasan-gce-selinux-root
2020/01/18 06:03 upstream ab7541c3addd 3de7aabb .config console log report syz ci-upstream-kasan-gce-root
2020/01/18 05:52 upstream ab7541c3addd 3de7aabb .config console log report syz ci-upstream-kasan-gce
2020/01/18 00:20 upstream ab7541c3addd 3de7aabb .config console log report syz ci-upstream-kasan-gce-smack-root
2020/01/18 03:12 upstream ab7541c3addd 3de7aabb .config console log report syz ci-upstream-kasan-gce-386
2020/01/17 22:02 net-old 5a9ef19454cd 3de7aabb .config console log report syz ci-upstream-net-this-kasan-gce
2020/01/18 01:59 net-next-old 56f200c78ce4 3de7aabb .config console log report syz ci-upstream-net-kasan-gce
2020/01/25 00:16 linux-next 2747d5fdab78 2e95ab33 .config console log report syz ci-upstream-linux-next-kasan-gce-root
2020/01/17 21:20 net-old 5a9ef19454cd 3de7aabb .config console log report ci-upstream-net-this-kasan-gce
* Struck through repros no longer work on HEAD.