general protection fault in rb

general protection fault in rb_next (3)

Status: fixed on 2019/08/27 17:15
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+ab4c44191771d56c4eda@syzkaller.appspotmail.com
Fix commit: 95fa145479fb bpf: sockmap/tls, close can race with map free
First crash: 1946d, last: 1946d

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 Read in psock_map_pop (log)
Repro: syz .config

Fix bisection: fixed by (bisect log) :
commit 95fa145479fbc0a0c1fd3274ceb42ec03c042a4a
Author: John Fastabend <john.fastabend@gmail.com>
Date: Fri Jul 19 17:29:22 2019 +0000

bpf: sockmap/tls, close can race with map free

▶ ▼ Discussions (3)

Title	Replies (including bot)	Last reply
Reminder: 36 open syzbot bugs in "net/bpf" subsystem	1 (1)	2019/07/03 06:01
Reminder: 30 open syzbot bugs in "net/bpf" subsystem	1 (1)	2019/06/24 05:01
general protection fault in rb_next (3)	0 (1)	2019/06/17 07:46

▶ ▼ Similar bugs (2)

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	general protection fault in rb_next kernel				1	2279d	2279d	8/28	fixed on 2018/08/07 13:43
upstream	general protection fault in rb_next (2) kernel				2	2106d	2113d	0/28	closed as dup on 2018/12/31 07:15

Sample crash report:

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: 8856 Comm: syz-executor.2 Not tainted 5.2.0-rc4+ #32
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rb_next+0xd7/0x140 lib/rbtree.c:529
Code: 49 89 dc 4c 89 eb 48 83 e3 fc 48 89 d8 75 c8 48 83 c4 08 5b 41 5c 41 5d 41 5e 5d c3 48 89 d0 48 8d 78 10 48 89 fa 48 c1 ea 03 <80> 3c 1a 00 75 1a 48 8b 50 10 48 85 d2 75 e3 48 83 c4 08 5b 41 5c
RSP: 0018:ffff8880ae809d70 EFLAGS: 00010007
RAX: 26f1e8c689c389ff RBX: dffffc0000000000 RCX: ffffffff87185c81
RDX: 04de3d18d1387141 RSI: ffffffff87185d10 RDI: 26f1e8c689c38a0f
RBP: ffff8880ae809d98 R08: ffff88808a51a440 R09: ffffed1015d06be0
R10: ffffed1015d06bdf R11: ffff8880ae835efb R12: ffff8880ae8275c0
R13: ffff8880ae827861 R14: dffffc0000000000 R15: ffff8880ae826d00
FS:  0000555555728940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000a8dc78 CR3: 00000000992f7000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 timerqueue_del+0xd8/0x150 lib/timerqueue.c:70
 __remove_hrtimer+0xa8/0x1c0 kernel/time/hrtimer.c:975
 __run_hrtimer kernel/time/hrtimer.c:1371 [inline]
 __hrtimer_run_queues+0x2a8/0xdd0 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 smp_apic_timer_interrupt+0x111/0x550 arch/x86/kernel/apic/apic.c:1066
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806
 </IRQ>
Modules linked in:

======================================================

Crashes (1):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2019/06/15 17:08	upstream	0011572c8830	442206d7	.config	console log	report	syz				ci-upstream-kasan-gce-root

* ~~Struck through~~ repros no longer work on HEAD.