syzbot


general protection fault in ax25_send_frame (2)

Status: upstream: reported on 2022/11/18 11:40
Reported-by: syzbot+4643bc868f47ad276452@syzkaller.appspotmail.com
Fix commit: e97c089d7a49 rose: Fix NULL pointer dereference in rose_send_frame()
Patched on: [ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-arm64 ci-upstream-gce-leak ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce ci-upstream-kmsan-gce-386 ci-upstream-linux-next-kasan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb], missing on: [ci-qemu2-riscv64]
First crash: 165d, last: 93d
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in ax25_send_frame 1411 867d 1498d 0/24 auto-closed as invalid on 2020/12/21 04:13
linux-4.14 general protection fault in ax25_send_frame 1 1377d 1377d 0/1 auto-closed as invalid on 2019/10/25 08:41
linux-4.19 general protection fault in ax25_send_frame 1 1337d 1337d 0/1 auto-closed as invalid on 2019/10/25 08:49

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc000000006c: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000360-0x0000000000000367]
CPU: 1 PID: 10715 Comm: syz-executor.3 Not tainted 6.0.0-rc4-syzkaller-00136-g0727a9a5fbc1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
RIP: 0010:ax25_dev_ax25dev include/net/ax25.h:342 [inline]
RIP: 0010:ax25_send_frame+0xe4/0x640 net/ax25/ax25_out.c:56
Code: 00 48 85 c0 49 89 c4 0f 85 fb 03 00 00 e8 34 cb 2b f9 49 8d bd 60 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 b1 04 00 00 4d 8b ad 60 03 00 00 4d 85 ed 0f 84
RSP: 0000:ffffc90004c77a00 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffff88814a308008 RCX: 0000000000000100
RDX: 000000000000006c RSI: ffffffff88503efc RDI: 0000000000000360
RBP: ffffffff91561460 R08: 0000000000000001 R09: ffffffff908e4a9f
R10: 0000000000000001 R11: 1ffffffff2020d9a R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000104 R15: 0000000000000000
FS:  0000555556215400(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f328000 CR3: 0000000050a64000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 rose_send_frame+0xcc/0x2f0 net/rose/rose_link.c:106
 rose_transmit_clear_request+0x1d5/0x290 net/rose/rose_link.c:255
 rose_rx_call_request+0x4c0/0x1bc0 net/rose/af_rose.c:1009
 rose_loopback_timer+0x19e/0x590 net/rose/rose_loopback.c:111
 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474
 expire_timers kernel/time/timer.c:1519 [inline]
 __run_timers.part.0+0x674/0xa80 kernel/time/timer.c:1790
 __run_timers kernel/time/timer.c:1768 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803
 __do_softirq+0x1d3/0x9c6 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x45/0xc0 arch/x86/kernel/apic/apic.c:1106
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0033:0x7fe1ccc37497
Code: 75 37 b8 00 00 00 80 48 01 d0 48 3d ff ff ff 7e 0f 87 2a 02 00 00 44 89 c0 c1 e8 10 44 31 c0 83 f0 3d 8d 04 c0 89 c7 c1 ef 04 <31> f8 69 c0 2d eb d4 27 31 c5 c1 e8 0f 31 c5 80 3d e4 de 09 01 00
RSP: 002b:00007fff5e3de460 EFLAGS: 00000a06
RAX: 000000009127bfa1 RBX: 00007fe1ccd9c018 RCX: 0000001b2f320000
RDX: ffffffff81e7790e RSI: 0000001b2f324438 RDI: 0000000009127bfa
RBP: 0000000081e7790e R08: ffffffff81e77903 R09: 00000000ab355ea3
R10: 00007fff5e3de630 R11: 0000000000000246 R12: 00007fe1ccd90000
R13: 0000000000000001 R14: 00000000000165f4 R15: ffffffff81e7790e
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ax25_dev_ax25dev include/net/ax25.h:342 [inline]
RIP: 0010:ax25_send_frame+0xe4/0x640 net/ax25/ax25_out.c:56
Code: 00 48 85 c0 49 89 c4 0f 85 fb 03 00 00 e8 34 cb 2b f9 49 8d bd 60 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 b1 04 00 00 4d 8b ad 60 03 00 00 4d 85 ed 0f 84
RSP: 0000:ffffc90004c77a00 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffff88814a308008 RCX: 0000000000000100
RDX: 000000000000006c RSI: ffffffff88503efc RDI: 0000000000000360
RBP: ffffffff91561460 R08: 0000000000000001 R09: ffffffff908e4a9f
R10: 0000000000000001 R11: 1ffffffff2020d9a R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000104 R15: 0000000000000000
FS:  0000555556215400(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f328000 CR3: 0000000050a64000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 48 85             	add    %cl,-0x7b(%rax)
   3:	c0 49 89 c4          	rorb   $0xc4,-0x77(%rcx)
   7:	0f 85 fb 03 00 00    	jne    0x408
   d:	e8 34 cb 2b f9       	callq  0xf92bcb46
  12:	49 8d bd 60 03 00 00 	lea    0x360(%r13),%rdi
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 b1 04 00 00    	jne    0x4e5
  34:	4d 8b ad 60 03 00 00 	mov    0x360(%r13),%r13
  3b:	4d 85 ed             	test   %r13,%r13
  3e:	0f                   	.byte 0xf
  3f:	84                   	.byte 0x84

Crashes (13):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci-upstream-net-this-kasan-gce 2022/09/15 02:25 net 0727a9a5fbc1 b884348d .config console log report info [disk image] [vmlinux] general protection fault in ax25_send_frame
ci-upstream-net-this-kasan-gce 2022/08/30 12:40 net cb10b0f91c5f 5b44472d .config console log report info general protection fault in ax25_send_frame
ci-upstream-net-this-kasan-gce 2022/08/29 01:39 net ebe5555c2f34 07177916 .config console log report info general protection fault in ax25_send_frame
ci-upstream-net-this-kasan-gce 2022/08/25 04:28 net 0c4a95417ee4 514514f6 .config console log report info general protection fault in ax25_send_frame
ci-upstream-net-kasan-gce 2022/11/01 22:48 net-next 99c8eb46773e edac4fd1 .config console log report info [disk image] [vmlinux] [kernel image] general protection fault in ax25_send_frame
ci-upstream-net-kasan-gce 2022/10/23 14:10 net-next 3bd5549bd479 c0b80a55 .config console log report info [disk image] [vmlinux] general protection fault in ax25_send_frame
ci-upstream-net-kasan-gce 2022/10/05 17:19 net-next 0326074ff465 267e3bb1 .config console log report info [disk image] [vmlinux] general protection fault in ax25_send_frame
ci-upstream-net-kasan-gce 2022/09/20 03:10 net-next 42666b2c452c dd9a85ff .config console log report info [disk image] [vmlinux] general protection fault in ax25_send_frame
ci-upstream-net-kasan-gce 2022/09/11 10:25 net-next 169ccf0e4082 356d8217 .config console log report info general protection fault in ax25_send_frame
ci-upstream-net-kasan-gce 2022/08/30 13:05 net-next f97e971dbdc7 5b44472d .config console log report info general protection fault in ax25_send_frame
ci-upstream-net-kasan-gce 2022/08/28 17:56 net-next 53a406803ca5 07177916 .config console log report info general protection fault in ax25_send_frame
ci-upstream-gce-arm64 2022/11/05 04:56 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci bbed346d5a96 6d752409 .config console log report info [disk image] [vmlinux] BUG: unable to handle kernel NULL pointer dereference in ax25_send_frame
ci-upstream-gce-arm64 2022/11/03 13:27 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci bbed346d5a96 7a2ebf95 .config console log report info [disk image] [vmlinux] BUG: unable to handle kernel NULL pointer dereference in ax25_send_frame
* Struck through repros no longer work on HEAD.