syzbot


BUG: unable to handle kernel paging request in tls_prots

Status: fixed on 2019/08/27 17:15
Subsystems: net bpf
[Documentation on labels]
Reported-by: syzbot+4207c7f3a443366d8aa2@syzkaller.appspotmail.com
Fix commit: 95fa145479fb bpf: sockmap/tls, close can race with map free
First crash: 1757d, last: 1757d
Cause bisection: introduced by (bisect log) :
commit e9db4ef6bf4ca9894bb324c76e01b8f1a16b2650
Author: John Fastabend <john.fastabend@gmail.com>
Date: Sat Jun 30 13:17:47 2018 +0000

  bpf: sockhash fix omitted bucket lock in sock_close

Crash: KASAN: use-after-free Write in bpf_tcp_close (log)
Repro: syz .config
  
Discussions (3)
Title Replies (including bot) Last reply
BUG: unable to handle kernel paging request in tls_prots 1 (3) 2019/08/19 22:34
Reminder: 36 open syzbot bugs in "net/bpf" subsystem 1 (1) 2019/07/03 06:01
[PATCH 0/2] tls, add unhash callback 12 (12) 2019/06/29 03:46

Sample crash report:
BUG: unable to handle page fault for address: 000000004125973f
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 92e1a067 P4D 92e1a067 PUD 0 
Thread overran stack, or stack corrupted
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 9943 Comm: blkid Not tainted 5.2.0-rc5+ #62
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:tls_prots+0x1a8a/0x3520
Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 70 0d 0f 86 ff ff ff ff 40 5d <28> 86 ff ff ff ff 60 6e 28 86 ff ff ff ff 00 de ed 85 ff ff ff ff
RSP: 0018:ffff888079bc7c10 EFLAGS: 00010082
RAX: ffff88808c5226c0 RBX: ffff88808cb36100 RCX: 1ffffffff116885c
RDX: 1ffff110118a44d8 RSI: 0000000041259740 RDI: ffff88808c523a70
RBP: ffff888079bc7c38 R08: ffff88808c5226c0 R09: ffffed1015d26c70
R10: ffffed1015d26c6f R11: ffff8880ae93637b R12: ffffffff860dd760
R13: ffffffff860dda75 R14: ffff888079bc7c08 R15: ffffffff8b1da9a0
FS:  00007fa341259740(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000004125973f CR3: 00000000907f6000 CR4: 00000000001406e0
Call Trace:
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
 tcp_bpf_unhash net/ipv4/tcp_bpf.c:550 [inline]
 tcp_bpf_unhash+0x315/0x390 net/ipv4/tcp_bpf.c:540
WARNING: kernel stack frame pointer at 00000000e809d5dc in blkid:9943 has bad value 000000009844d018
unwind stack type:0 next_sp:000000005f927a44 mask:0x2 graph_idx:0
000000002401cb95: ffff888079bc7c68 (0xffff888079bc7c68)
00000000c24ed912: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000db5b548d: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000479aff76: ffff88808cb36100 (0xffff88808cb36100)
000000004473e5aa: 0000000000000000 ...
000000009d12a602: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
00000000ba44e25c: ffff888079bc7c98 (0xffff888079bc7c98)
00000000e1eb23e4: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000f7d29ffb: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000dc871c27: ffff88808cb36100 (0xffff88808cb36100)
000000003824545e: 0000000000000000 ...
000000008a182c7c: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
000000001c7a51e7: ffff888079bc7cc8 (0xffff888079bc7cc8)
0000000049da0237: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
000000009c31c0da: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
0000000024f3129d: ffff88808cb36100 (0xffff88808cb36100)
0000000040823c88: 0000000000000000 ...
000000004c33f42e: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
00000000fa38e5a4: ffff888079bc7cf8 (0xffff888079bc7cf8)
0000000030a46a60: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000313cd10c: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
000000003feafbe9: ffff88808cb36100 (0xffff88808cb36100)
00000000b2d0344c: 0000000000000000 ...
00000000a54c1af0: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
00000000d4027d6c: ffff888079bc7d28 (0xffff888079bc7d28)
000000009ee98499: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000cc716643: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000f66028fc: ffff88808cb36100 (0xffff88808cb36100)
00000000f1a9f4a4: 0000000000000000 ...
0000000093e98749: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
0000000069764410: ffff888079bc7d58 (0xffff888079bc7d58)
0000000099cc4d5e: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
000000008452556b: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
000000009d210107: ffff88808cb36100 (0xffff88808cb36100)
000000000b3d1c61: 0000000000000000 ...
0000000029482aba: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
000000000080c2ff: ffff888079bc7d88 (0xffff888079bc7d88)
000000004e072bc8: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000049c3c65: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000b89e7d9b: ffff88808cb36100 (0xffff88808cb36100)
000000004f6d4a66: 0000000000000000 ...
0000000062d2c1b7: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
0000000064dd81c9: ffff888079bc7db8 (0xffff888079bc7db8)
000000003089fca0: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
0000000080e7f1f9: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000487c3ec3: ffff88808cb36100 (0xffff88808cb36100)
00000000291b99a5: 0000000000000000 ...
00000000879c3ace: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
0000000088f16e91: ffff888079bc7de8 (0xffff888079bc7de8)
00000000feaf9900: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000699d8a79: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000ea800749: ffff88808cb36100 (0xffff88808cb36100)
000000002c99629d: 0000000000000000 ...
00000000f89aef64: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
000000008a8c9aec: ffff888079bc7e18 (0xffff888079bc7e18)
0000000050ff6d78: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
000000008764d630: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
0000000091e33368: ffff88808cb36100 (0xffff88808cb36100)
00000000e1a0ace5: 0000000000000000 ...
00000000cbc751ab: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
00000000d4f9acf4: ffff888079bc7e48 (0xffff888079bc7e48)
0000000081fc1715: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000aa6f1bc2: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000d2a9e7ce: ffff88808cb36100 (0xffff88808cb36100)
000000006f96fab3: 0000000000000000 ...
00000000aeaeead6: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
00000000f35f95f5: ffff888079bc7e78 (0xffff888079bc7e78)
000000008c846b2f: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
000000001c6a7237: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000799c1d50: ffff88808cb36100 (0xffff88808cb36100)
00000000447f9e03: 0000000000000000 ...
00000000ec08ab6f: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
0000000079b88671: ffff888079bc7ea8 (0xffff888079bc7ea8)
0000000057ceab90: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000a3af49c4: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000c8233266: ffff88808cb36100 (0xffff88808cb36100)
00000000a4346829: 0000000000000000 ...
00000000a77b30e0: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
000000009289d9ef: ffff888079bc7ed8 (0xffff888079bc7ed8)
0000000093a94b95: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000bba52dcd: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
000000004ba72af3: ffff88808cb36100 (0xffff88808cb36100)
000000002713380e: 0000000000000000 ...
0000000082b4f5fe: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
00000000fd331aa8: ffff888079bc7f08 (0xffff888079bc7f08)
00000000a125cb7a: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000b176b5fe: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
0000000021b424c8: ffff88808cb36100 (0xffff88808cb36100)
00000000c8aca3a7: 0000000000000000 ...
00000000ae0e04d5: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
00000000218dfe2f: ffff888079bc7f38 (0xffff888079bc7f38)
000000006f81db8c: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
000000005415d20a: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000cd8b4d0d: ffff88808cb36100 (0xffff88808cb36100)
0000000028dde223: 0000000000000000 ...
00000000f1bac7a7: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
00000000819b4e09: ffff888079bc7f68 (0xffff888079bc7f68)
0000000040faf187: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000d40fc060: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
000000002efea550: ffff88808cb36100 (0xffff88808cb36100)
0000000056721274: 0000000000000000 ...
000000008c6a3097: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
0000000039ab3cf0: ffff888079bc7f98 (0xffff888079bc7f98)
00000000b825c1f0: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
000000005d65596f: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000a0cc451f: ffff88808cb36100 (0xffff88808cb36100)
00000000e7f05b41: 0000000000000000 ...
0000000049404ce5: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
000000001a81ddbb: ffff888079bc7fc8 (0xffff888079bc7fc8)
000000003afd376f: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
0000000067da2263: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
00000000951815ed: ffff88808cb36100 (0xffff88808cb36100)
00000000eb36eac9: 0000000000000000 ...
0000000084ea5e52: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
00000000e809d5dc: ffff888079bc7ff8 (0xffff888079bc7ff8)
00000000e50d63ae: ffffffff860dda75 (tcp_bpf_unhash+0x315/0x390)
00000000d90e11b6: ffffffff860dd760 (tcp_bpf_recvmsg+0xa40/0xa40)
000000000a06acca: ffff88808cb36100 (0xffff88808cb36100)
000000006c7f5c3c: 0000000000000000 ...
00000000e157dcd0: ffffffff8b1da9a0 (tls_prots+0x1a80/0x3520)
000000009844d018: ffff888079bc8028 (0xffff888079bc8028)
Modules linked in:
CR2: 000000004125973f
---[ end trace 79fdcdc2ec39f3e0 ]---
RIP: 0010:tls_prots+0x1a8a/0x3520
Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 70 0d 0f 86 ff ff ff ff 40 5d <28> 86 ff ff ff ff 60 6e 28 86 ff ff ff ff 00 de ed 85 ff ff ff ff
RSP: 0018:ffff888079bc7c10 EFLAGS: 00010082
RAX: ffff88808c5226c0 RBX: ffff88808cb36100 RCX: 1ffffffff116885c
RDX: 1ffff110118a44d8 RSI: 0000000041259740 RDI: ffff88808c523a70
RBP: ffff888079bc7c38 R08: ffff88808c5226c0 R09: ffffed1015d26c70
R10: ffffed1015d26c6f R11: ffff8880ae93637b R12: ffffffff860dd760
R13: ffffffff860dda75 R14: ffff888079bc7c08 R15: ffffffff8b1da9a0
FS:  00007fa341259740(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000004125973f CR3: 00000000907f6000 CR4: 00000000001406e0

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/06/26 08:35 net-old 904d88d743b0 0a8d1a96 .config console log report syz ci-upstream-net-this-kasan-gce
* Struck through repros no longer work on HEAD.