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KASAN: use-after-free Read in ccid2_hc_tx_packet_recv

Status: auto-closed as invalid on 2019/10/25 08:37
Reported-by: syzbot+0bbacd0b957f9f62683a@syzkaller.appspotmail.com
First crash: 1795d, last: 1795d
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 KASAN: use-after-free Read in ccid2_hc_tx_packet_recv (2) C done inconclusive 3 1436d 1644d 0/1 upstream: reported C repro on 2019/11/09 21:41
upstream KASAN: use-after-free Read in ccid2_hc_tx_packet_recv dccp C done error 102 9d11h 2230d 0/26 upstream: reported C repro on 2018/04/02 09:20
linux-4.19 KASAN: use-after-free Read in ccid2_hc_tx_packet_recv C done error 2 1429d 1649d 0/1 upstream: reported C repro on 2019/11/04 11:20

Sample crash report:
R13: 00000000004c683e R14: 00000000004db7c0 R15: 0000000000000007
dccp_parse_options: DCCP(ffff8880653ccb00): Option 32 (len=7) error=9
==================================================================
BUG: KASAN: use-after-free in ccid2_hc_tx_packet_recv+0x1cf3/0x1fa4 net/dccp/ccids/ccid2.c:599
Read of size 1 at addr ffff88809de54fe2 by task syz-executor.2/17459

CPU: 1 PID: 17459 Comm: syz-executor.2 Not tainted 4.14.125 #19
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x138/0x19c lib/dump_stack.c:53
 print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:427
 ccid2_hc_tx_packet_recv+0x1cf3/0x1fa4 net/dccp/ccids/ccid2.c:599
 ccid_hc_tx_packet_recv net/dccp/ccid.h:192 [inline]
 dccp_deliver_input_to_ccids+0x1d5/0x250 net/dccp/input.c:186
 dccp_rcv_established net/dccp/input.c:378 [inline]
 dccp_rcv_established+0x6b/0xb0 net/dccp/input.c:368
 dccp_v4_do_rcv+0x122/0x170 net/dccp/ipv4.c:656
 sk_backlog_rcv include/net/sock.h:912 [inline]
 __release_sock+0x12d/0x350 net/core/sock.c:2262
 release_sock+0x59/0x1b0 net/core/sock.c:2777
 dccp_sendmsg+0x57e/0x950 net/dccp/proto.c:813
 inet_sendmsg+0x122/0x500 net/ipv4/af_inet.c:762
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xce/0x110 net/socket.c:656
 ___sys_sendmsg+0x349/0x840 net/socket.c:2062
 __sys_sendmmsg+0x152/0x3a0 net/socket.c:2152
 SYSC_sendmmsg net/socket.c:2183 [inline]
 SyS_sendmmsg+0x35/0x60 net/socket.c:2178
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459279
RSP: 002b:00007ff76b0efc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007ff76b0efc90 RCX: 0000000000459279
RDX: 04000000000001e6 RSI: 0000000020000c00 RDI: 0000000000000006
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff76b0f06d4
R13: 00000000004c683e R14: 00000000004db7c0 R15: 0000000000000007

Allocated by task 17459:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x45/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc mm/kasan/kasan.c:551 [inline]
 kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:529
 __do_kmalloc_node mm/slab.c:3682 [inline]
 __kmalloc_node_track_caller+0x51/0x80 mm/slab.c:3696
 __kmalloc_reserve.isra.0+0x40/0xe0 net/core/skbuff.c:137
 __alloc_skb+0xcf/0x500 net/core/skbuff.c:205
 alloc_skb include/linux/skbuff.h:980 [inline]
 dccp_send_ack+0xc7/0x330 net/dccp/output.c:580
 ccid2_hc_rx_packet_recv+0x10e/0x180 net/dccp/ccids/ccid2.c:778
 ccid_hc_rx_packet_recv net/dccp/ccid.h:185 [inline]
 dccp_deliver_input_to_ccids+0xdd/0x250 net/dccp/input.c:180
 dccp_rcv_established net/dccp/input.c:378 [inline]
 dccp_rcv_established+0x6b/0xb0 net/dccp/input.c:368
 dccp_v4_do_rcv+0x122/0x170 net/dccp/ipv4.c:656
 sk_backlog_rcv include/net/sock.h:912 [inline]
 __sk_receive_skb+0x226/0x950 net/core/sock.c:511
 dccp_v4_rcv+0xd47/0x1903 net/dccp/ipv4.c:877
 ip_local_deliver_finish+0x25e/0xad0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:250 [inline]
 NF_HOOK include/linux/netfilter.h:244 [inline]
 ip_local_deliver+0x1c3/0x4a0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:465 [inline]
 ip_rcv_finish+0x7be/0x1a50 net/ipv4/ip_input.c:396
 NF_HOOK include/linux/netfilter.h:250 [inline]
 NF_HOOK include/linux/netfilter.h:244 [inline]
 ip_rcv+0xaa5/0x112b net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x1d58/0x2aa0 net/core/dev.c:4477
 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4515
 process_backlog+0x21f/0x730 net/core/dev.c:5197
 napi_poll net/core/dev.c:5598 [inline]
 net_rx_action+0x490/0xf80 net/core/dev.c:5664
 __do_softirq+0x244/0x9a0 kernel/softirq.c:288

Freed by task 17459:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x45/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kfree+0xcc/0x270 mm/slab.c:3815
 skb_free_head+0x8b/0xb0 net/core/skbuff.c:554
 skb_release_data+0x4af/0x700 net/core/skbuff.c:574
 skb_release_all+0x4d/0x60 net/core/skbuff.c:631
 __kfree_skb net/core/skbuff.c:645 [inline]
 kfree_skb+0xb5/0x340 net/core/skbuff.c:663
 dccp_v4_do_rcv net/dccp/ipv4.c:691 [inline]
 dccp_v4_do_rcv+0x13e/0x170 net/dccp/ipv4.c:651
 sk_backlog_rcv include/net/sock.h:912 [inline]
 __release_sock+0x12d/0x350 net/core/sock.c:2262
 release_sock+0x59/0x1b0 net/core/sock.c:2777
 dccp_sendmsg+0x57e/0x950 net/dccp/proto.c:813
 inet_sendmsg+0x122/0x500 net/ipv4/af_inet.c:762
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xce/0x110 net/socket.c:656
 ___sys_sendmsg+0x349/0x840 net/socket.c:2062
 __sys_sendmmsg+0x152/0x3a0 net/socket.c:2152
 SYSC_sendmmsg net/socket.c:2183 [inline]
 SyS_sendmmsg+0x35/0x60 net/socket.c:2178
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

The buggy address belongs to the object at ffff88809de54b40
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 1186 bytes inside of
 2048-byte region [ffff88809de54b40, ffff88809de55340)
The buggy address belongs to the page:
page:ffffea0002779500 count:1 mapcount:0 mapping:ffff88809de542c0 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000008100(slab|head)
raw: 01fffc0000008100 ffff88809de542c0 0000000000000000 0000000100000003
raw: ffffea000186d7a0 ffffea0001a3b0a0 ffff8880aa800c40 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809de54e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88809de54f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88809de54f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff88809de55000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88809de55080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
device syz_tun entered promiscuous mode
device syz_tun left promiscuous mode

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/06/11 21:48 linux-4.14.y 2bf3258a12af 5b5826d0 .config console log report ci2-linux-4-14
* Struck through repros no longer work on HEAD.