syzbot


general protection fault in free_verifier_state (3)

Status: fixed on 2020/02/18 14:31
Subsystems: bpf
[Documentation on labels]
Reported-by: syzbot+b296579ba5015704d9fa@syzkaller.appspotmail.com
Fix commit: f59bbfc2f609 bpf: Fix error path under memory pressure
First crash: 1600d, last: 1590d
Discussions (2)
Title Replies (including bot) Last reply
[PATCH bpf-next] bpf: Fix error path under memory pressure 4 (4) 2020/01/22 15:56
general protection fault in free_verifier_state (3) 1 (3) 2020/01/21 19:16
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in free_verifier_state (2) bpf C 2 2334d 2333d 4/26 fixed on 2018/02/01 04:00
upstream general protection fault in free_verifier_state bpf C 2 2352d 2352d 3/26 fixed on 2017/12/27 08:45

Sample crash report:
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441339
RDX: 0000000000000048 RSI: 00000000200017c0 RDI: 0000000000000005
RBP: 00000000006cc018 R08: 0000000000000002 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402280
R13: 0000000000402310 R14: 0000000000000000 R15: 0000000000000000
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 9996 Comm: syz-executor310 Not tainted 5.5.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:free_verifier_state+0x49/0x1d0 kernel/bpf/verifier.c:744
Code: db 48 83 ec 20 48 89 45 b8 48 c1 e8 03 4c 01 f8 89 75 c4 48 89 45 c8 e8 05 9c f2 ff 4c 63 f3 4f 8d 2c f4 4c 89 e8 48 c1 e8 03 <42> 80 3c 38 00 0f 85 2b 01 00 00 4f 8d 34 f4 49 8b 3e 48 85 ff 48
RSP: 0018:ffffc90002007688 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8184dd58
RDX: 0000000000000000 RSI: ffffffff8182644b RDI: 0000000000000000
RBP: ffffc900020076d0 R08: ffff888098656280 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  000000000236b880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 0000000098345000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 do_check_common+0x2ec7/0x9650 kernel/bpf/verifier.c:9597
 do_check_main kernel/bpf/verifier.c:9654 [inline]
 bpf_check+0x84ed/0xbb07 kernel/bpf/verifier.c:10009
 bpf_prog_load+0xeab/0x17f0 kernel/bpf/syscall.c:2095
 __do_sys_bpf+0x1521/0x41e0 kernel/bpf/syscall.c:3387
 __se_sys_bpf kernel/bpf/syscall.c:3346 [inline]
 __x64_sys_bpf+0x73/0xb0 kernel/bpf/syscall.c:3346
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x441339
Code: e8 5c ae 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 bb 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffe7971f348 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441339
RDX: 0000000000000048 RSI: 00000000200017c0 RDI: 0000000000000005
RBP: 00000000006cc018 R08: 0000000000000002 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402280
R13: 0000000000402310 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace af38d247c1b207c2 ]---
RIP: 0010:free_verifier_state+0x49/0x1d0 kernel/bpf/verifier.c:744
Code: db 48 83 ec 20 48 89 45 b8 48 c1 e8 03 4c 01 f8 89 75 c4 48 89 45 c8 e8 05 9c f2 ff 4c 63 f3 4f 8d 2c f4 4c 89 e8 48 c1 e8 03 <42> 80 3c 38 00 0f 85 2b 01 00 00 4f 8d 34 f4 49 8b 3e 48 85 ff 48
RSP: 0018:ffffc90002007688 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8184dd58
RDX: 0000000000000000 RSI: ffffffff8182644b RDI: 0000000000000000
RBP: ffffc900020076d0 R08: ffff888098656280 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  000000000236b880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 0000000098345000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/01/21 19:04 bpf-next 2e3a94aa2bfc 8eda0b95 .config console log report syz C ci-upstream-bpf-next-kasan-gce
2020/01/21 18:39 bpf-next 2e3a94aa2bfc 8eda0b95 .config console log report ci-upstream-bpf-next-kasan-gce
2020/01/15 21:28 bpf-next 5640a771d797 f9b69507 .config console log report ci-upstream-bpf-next-kasan-gce
2020/01/14 18:16 bpf-next 6dd42aa17fdd 32881205 .config console log report ci-upstream-bpf-next-kasan-gce
2020/01/11 11:23 bpf-next ac065870d928 4c04afaa .config console log report ci-upstream-bpf-next-kasan-gce
* Struck through repros no longer work on HEAD.