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KASAN: use-after-free Read in ccid2_hc_tx_packet_recv (2)

Status: upstream: reported C repro on 2019/11/09 21:41
Reported-by: syzbot+f82d6c1bfc332d1196b2@syzkaller.appspotmail.com
First crash: 2258d, last: 2050d
Cause bisection: introduced by (bisect log) :
commit 3fa6f616a7a4d0bdf4d877d530456d8a5c3b109b
Author: David Ahern <dsahern@gmail.com>
Date: Mon Aug 7 15:44:17 2017 +0000

  net: ipv4: add second dif to inet socket lookups

Crash: KASAN: use-after-free Read in ccid2_hc_tx_packet_recv (log)
Repro: C syz .config
  
Fix bisection the fix commit could be any of (bisect log):
  c9fda4f22428 Linux 4.14.152
  4139fb08c05f Linux 4.14.187
   
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 KASAN: use-after-free Read in ccid2_hc_tx_packet_recv 19 1 2409d 2409d 0/1 auto-closed as invalid on 2019/10/25 08:37
upstream KASAN: use-after-free Read in ccid2_hc_tx_packet_recv dccp 19 C done error 111 277d 2844d 0/29 auto-obsoleted due to no activity on 2025/07/21 16:54
linux-4.19 KASAN: use-after-free Read in ccid2_hc_tx_packet_recv 19 C done error 2 2043d 2263d 0/1 upstream: reported C repro on 2019/11/04 11:20
linux-6.1 KASAN: use-after-free Read in ccid2_hc_tx_packet_recv origin:upstream missing-backport 19 C inconclusive 6 45d 437d 0/3 upstream: reported C repro on 2024/11/04 02:55
▶ ▼ Last patch testing requests (2)
Created Duration User Patch Repo Result
2023/01/20 13:32 15m retest repro linux-4.14.y report log
2022/09/05 02:27 10m retest repro linux-4.14.y report log
▶ ▼ Fix bisection attempts (7)
Created Duration User Patch Repo Result
2020/07/05 02:26 30m bisect fix linux-4.14.y OK (2) job log
2020/06/04 23:39 23m bisect fix linux-4.14.y OK (0) job log log
2020/05/05 23:12 26m bisect fix linux-4.14.y OK (0) job log log
2020/04/05 22:33 23m bisect fix linux-4.14.y OK (0) job log log
2020/03/06 21:56 24m bisect fix linux-4.14.y OK (0) job log log
2020/02/05 15:50 24m bisect fix linux-4.14.y OK (0) job log log
2020/01/06 15:25 24m bisect fix linux-4.14.y OK (0) job log log

Sample crash report:
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000038
R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff
R13: 0000000000000007 R14: 0000000000000000 R15: 0000000000000000
dccp_parse_options: DCCP(ffff8880720a0a40): 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 ffff888080f1b69d by task syz-executor278/6987

CPU: 0 PID: 6987 Comm: syz-executor278 Not tainted 4.14.152 #0
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+0x138/0x197 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:2264
 release_sock+0x59/0x1b0 net/core/sock.c:2779
 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: 0033:0x444279
RSP: 002b:00007ffe668258b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000444279
RDX: 04000000000001e6 RSI: 0000000020000c00 RDI: 0000000000000006
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000038
R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff
R13: 0000000000000007 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 6987:
 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:468 [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+0x1eae/0x2ca0 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 6987:
 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:2264
 release_sock+0x59/0x1b0 net/core/sock.c:2779
 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 ffff888080f1b200
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 1181 bytes inside of
 2048-byte region [ffff888080f1b200, ffff888080f1ba00)
The buggy address belongs to the page:
page:ffffea000203c680 count:1 mapcount:0 mapping:ffff888080f1a100 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000008100(slab|head)
raw: 01fffc0000008100 ffff888080f1a100 0000000000000000 0000000100000003
raw: ffffea0001c966a0 ffffea0001c969a0 ffff8880aa800c40 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888080f1b580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888080f1b600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888080f1b680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff888080f1b700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888080f1b780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/09 21:10 linux-4.14.y c9fda4f22428 1e35461e .config console log report syz C ci2-linux-4-14
2019/12/07 15:25 linux-4.14.y a844dc4c5442 85f26751 .config console log report ci2-linux-4-14
2019/11/09 20:40 linux-4.14.y c9fda4f22428 1e35461e .config console log report ci2-linux-4-14
* Struck through repros no longer work on HEAD.