kernel panic: Damn Damn! Unhandled trap in the kernel! (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: fbc86e4f 9ns: treat opens of symlinks as EINVAL
git tree: akaros
console output: https://syzkaller.appspot.com/x/log.txt?x=12c1e318a00000
kernel config: https://syzkaller.appspot.com/x/.config?x=bc709c3b83482973
dashboard link: https://syzkaller.appspot.com/bug?extid=23841a68e22cc895cab7

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+23841a...@syzkaller.appspotmail.com

kernel panic at kern/arch/x86/trap.c:628, from core 1: Damn Damn!
Unhandled trap in the kernel!
HW TRAP frame at 0xfffffff000014d00 on core 1
rax 0x0000000000000001
rbx 0xf7e9484889489055
rcx 0x0000000000000001
rdx 0xf7e948488948905d
rbp 0xfffffff000014dc8
rsi 0x00000000ffffff9c
rdi 0xf7e948488948905d
r8 0x0000000000000000
r9 0x0000000000000000
r10 0x000010000000a4c0
r11 0x0000000000000202
r12 0xffff80000218bc70
r13 0x00000000ffffff9c
r14 0x0000000000000002
r15 0xffff80000218b900
trap 0x0000000d General Protection
gsbs 0xffffffffc8e37dc0
fsbs 0x0000000000000000
err 0x--------00000000
rip 0xffffffffc2007b87
cs 0x------------0008
flag 0x0000000000010286
rsp 0xfffffff000014dc8
ss 0x------------0010
Backtrace of kernel context on Core 1:
#01 [<0xffffffffc2007b87>] in kref_put at include/kref.h:67
#02 [<0xffffffffc2007f06>] in remove_fd_tap at src/fdtap.c:140
#03 [< [inline] >] in handle_tap_req at src/syscall.c:2434
#03 [<0xffffffffc2058c1c>] in sys_tap_fds at src/syscall.c:2456
#04 [<0xffffffffc2059e69>] in syscall at src/syscall.c:2575
#05 [<0xffffffffc205aa18>] in run_local_syscall at src/syscall.c:2612
#06 [<0xffffffffc205af59>] in prep_syscalls at src/syscall.c:2632
#07 [<0xffffffffc20ac842>] in sysenter_callwrapper at arch/x86/trap.c:877


---
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[syzbot]

syzbot has found a reproducer for the following crash on:

HEAD commit: fbc86e4f 9ns: treat opens of symlinks as EINVAL
git tree: akaros

console output: https://syzkaller.appspot.com/x/log.txt?x=13d17b28a00000

kernel config: https://syzkaller.appspot.com/x/.config?x=bc709c3b83482973
dashboard link: https://syzkaller.appspot.com/bug?extid=23841a68e22cc895cab7

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13eb9840a00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=120cb728a00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+23841a...@syzkaller.appspotmail.com

kernel panic at kern/arch/x86/trap.c:628, from core 0: Damn Damn!

Unhandled trap in the kernel!

HW TRAP frame at 0xfffffff00006dd00 on core 0
rax 0x0000000000000001
rbx 0x002c000000000040
rcx 0x0000000000000000
rdx 0x002c000000000048
rbp 0xfffffff00006ddc8
rsi 0x00000000ffffff9c
rdi 0x002c000000000048
r8 0x0000000000000000
r9 0x0000000000000000
r10 0x0000000000000000

r11 0x0000000000000202
r12 0xffff80000218bc70
r13 0x00000000ffffff9c
r14 0x0000000000000002
r15 0xffff80000218b900
trap 0x0000000d General Protection

gsbs 0xffffffffc8e37b00

fsbs 0x0000000000000000
err 0x--------00000000
rip 0xffffffffc2007b87
cs 0x------------0008

flag 0x0000000000010202
rsp 0xfffffff00006ddc8
ss 0x------------0010
Backtrace of kernel context on Core 0: