syzbot


KMSAN: uninit-value in sctp_ootb_pkt_new

Status: upstream: reported C repro on 2020/04/16 07:05
Reported-by: syzbot+6751381fe5a26df5b74d@syzkaller.appspotmail.com
First crash: 815d, last: 696d
Patch testing requests:
Created Duration User Patch Repo Result
2021/05/04 23:52 46m phil@philpotter.co.uk https://github.com/google/kmsan.git master OK

Sample crash report:
batman_adv: batadv0: Interface activated: batadv_slave_1
=====================================================
BUG: KMSAN: uninit-value in __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline]
BUG: KMSAN: uninit-value in __fswab32 include/uapi/linux/swab.h:60 [inline]
BUG: KMSAN: uninit-value in sctp_ootb_pkt_new+0x202/0x540 net/sctp/sm_statefuns.c:6256
CPU: 0 PID: 8800 Comm: syz-executor949 Not tainted 5.6.0-rc7-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+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline]
 __fswab32 include/uapi/linux/swab.h:60 [inline]
 sctp_ootb_pkt_new+0x202/0x540 net/sctp/sm_statefuns.c:6256
 sctp_sf_tabort_8_4_8+0xe6/0x7e0 net/sctp/sm_statefuns.c:3372
 sctp_sf_do_5_1B_init+0x6be/0x1b60 net/sctp/sm_statefuns.c:338
 sctp_do_sm+0x2b4/0x9a30 net/sctp/sm_sideeffect.c:1153
 sctp_endpoint_bh_rcv+0xd54/0xfe0 net/sctp/endpointola.c:395
 sctp_inq_push+0x300/0x420 net/sctp/inqueue.c:80
 sctp_rcv+0x48b9/0x5410 net/sctp/input.c:256
 ip_protocol_deliver_rcu+0x700/0xbc0 net/ipv4/ip_input.c:204
 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ip_local_deliver+0x62a/0x7c0 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:442 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:428 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ip_rcv+0x6cf/0x750 net/ipv4/ip_input.c:538
 __netif_receive_skb_one_core net/core/dev.c:5187 [inline]
 __netif_receive_skb net/core/dev.c:5301 [inline]
 netif_receive_skb_internal net/core/dev.c:5391 [inline]
 netif_receive_skb+0xbb5/0xf20 net/core/dev.c:5450
 tun_rx_batched include/linux/skbuff.h:4351 [inline]
 tun_get_user+0x6aef/0x6f60 drivers/net/tun.c:1997
 tun_chr_write_iter+0x1f2/0x360 drivers/net/tun.c:2026
 call_write_iter include/linux/fs.h:1902 [inline]
 new_sync_write fs/read_write.c:483 [inline]
 __vfs_write+0xa5a/0xca0 fs/read_write.c:496
 vfs_write+0x44a/0x8f0 fs/read_write.c:558
 ksys_write+0x267/0x450 fs/read_write.c:611
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write+0x92/0xb0 fs/read_write.c:620
 __x64_sys_write+0x4a/0x70 fs/read_write.c:620
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x443659
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 7b 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff60095968 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000003172 RCX: 0000000000443659
RDX: 000000000000002e RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 00007fff60095990 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000aa14 R11: 0000000000000246 R12: 656c6c616b7a7973
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2801 [inline]
 __kmalloc_node_track_caller+0xb40/0x1200 mm/slub.c:4420
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x2fd/0xac0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1081 [inline]
 alloc_skb_with_frags+0x18c/0xa70 net/core/skbuff.c:5764
 sock_alloc_send_pskb+0xada/0xc60 net/core/sock.c:2245
 tun_alloc_skb drivers/net/tun.c:1529 [inline]
 tun_get_user+0x10ae/0x6f60 drivers/net/tun.c:1843
 tun_chr_write_iter+0x1f2/0x360 drivers/net/tun.c:2026
 call_write_iter include/linux/fs.h:1902 [inline]
 new_sync_write fs/read_write.c:483 [inline]
 __vfs_write+0xa5a/0xca0 fs/read_write.c:496
 vfs_write+0x44a/0x8f0 fs/read_write.c:558
 ksys_write+0x267/0x450 fs/read_write.c:611
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write+0x92/0xb0 fs/read_write.c:620
 __x64_sys_write+0x4a/0x70 fs/read_write.c:620
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
=====================================================

Crashes (16):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kmsan-gce 2020/04/26 14:08 https://github.com/google/kmsan.git master bfa90a4a3f3f 99b258dd .config log report syz C
ci-upstream-kmsan-gce 2020/07/19 09:38 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config log report
ci-upstream-kmsan-gce 2020/07/18 18:01 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config log report
ci-upstream-kmsan-gce 2020/07/18 13:19 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config log report
ci-upstream-kmsan-gce 2020/07/17 16:09 https://github.com/google/kmsan.git master f0d5ec902b23 9c812472 .config log report
ci-upstream-kmsan-gce 2020/07/17 01:14 https://github.com/google/kmsan.git master f0d5ec902b23 54b3c45e .config log report
ci-upstream-kmsan-gce 2020/07/17 01:05 https://github.com/google/kmsan.git master f0d5ec902b23 54b3c45e .config log report
ci-upstream-kmsan-gce 2020/07/16 04:32 https://github.com/google/kmsan.git master f0d5ec902b23 f3bec699 .config log report
ci-upstream-kmsan-gce 2020/04/26 12:49 https://github.com/google/kmsan.git master bfa90a4a3f3f 99b258dd .config log report
ci-upstream-kmsan-gce 2020/04/11 19:32 https://github.com/google/kmsan.git master 75303409203b a8c6a3f8 .config log report
ci-upstream-kmsan-gce-386 2020/08/09 00:44 https://github.com/google/kmsan.git master ce8056d1f79e f721e4a0 .config log report
ci-upstream-kmsan-gce-386 2020/08/08 23:19 https://github.com/google/kmsan.git master ce8056d1f79e f721e4a0 .config log report
ci-upstream-kmsan-gce-386 2020/08/02 03:13 https://github.com/google/kmsan.git master 93f54a72361a d895b3be .config log report
ci-upstream-kmsan-gce-386 2020/07/30 03:57 https://github.com/google/kmsan.git master 93f54a72361a 233283a1 .config log report
ci-upstream-kmsan-gce-386 2020/07/19 09:33 https://github.com/google/kmsan.git master 14525656779e 9c812472 .config log report
ci-upstream-kmsan-gce-386 2020/07/16 04:43 https://github.com/google/kmsan.git master f0d5ec902b23 f3bec699 .config log report