BUG: unable to handle kernel paging request in __syscall_return_slowpath

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 04300d66 Merge tag 'riscv-for-linus-5.8-rc7' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13e6fb64900000
kernel config: https://syzkaller.appspot.com/x/.config?x=f87a5e4232fdb267
dashboard link: https://syzkaller.appspot.com/bug?extid=8c37a0f3f00cf0dc8cfd
compiler: gcc (GCC) 10.1.0-syz 20200507
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14c88a9c900000

Bisection is inconclusive: the issue happens on the oldest tested release.

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1101b8a8900000
final oops: https://syzkaller.appspot.com/x/report.txt?x=1301b8a8900000
console output: https://syzkaller.appspot.com/x/log.txt?x=1501b8a8900000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8c37a0...@syzkaller.appspotmail.com

BUG: unable to handle page fault for address: fffffffffffffffe
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 9a7c067 P4D 9a7c067 PUD 9a7e067 PMD 0
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 3892 Comm: systemd-udevd Not tainted 5.8.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__syscall_return_slowpath+0x0/0x280 arch/x86/entry/common.c:332
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 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
RSP: 0018:ffffc900015b7f38 EFLAGS: 00010283
RAX: fffffffffffffffe RBX: 0000000000000015 RCX: 1ffff920002b6fd5
RDX: ffff88809d834000 RSI: ffffffff81bcb65f RDI: ffffc900015b7f58
RBP: ffffc900015b7f58 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f0863b0d8c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffffe CR3: 000000009a278000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
do_syscall_64+0x6c/0xe0 arch/x86/entry/common.c:393
entry_SYSCALL_64_after_hwframe+0x44/0xa9
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#2] PREEMPT SMP KASAN
CPU: 1 PID: 3892 Comm: systemd-udevd Not tainted 5.8.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:in_gate_area_no_mm+0x0/0x6a arch/x86/entry/vsyscall/vsyscall_64.c:343
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 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
RSP: 0018:ffffc900015b74a0 EFLAGS: 00010093
RAX: 0000000000000000 RBX: ffffc900015b7540 RCX: ffffffff816a6330
RDX: ffff88809d834000 RSI: ffffffff816a635b RDI: 00007f08629809c7
RBP: 00007f08629809c7 R08: ffffc900015b7650 R09: ffffffff8c8d7109
R10: 00007f08629809c7 R11: 0000000000000000 R12: ffffc900015b7650
R13: 0000000000000001 R14: 00007f08629809c7 R15: ffffc900015b7560
FS: 00007f0863b0d8c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000009a278000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
is_kernel include/linux/kallsyms.h:44 [inline]
is_ksym_addr include/linux/kallsyms.h:50 [inline]
kallsyms_lookup+0xc3/0x2e0 kernel/kallsyms.c:290
__sprint_symbol+0x9c/0x1c0 kernel/kallsyms.c:363
symbol_string+0x14c/0x370 lib/vsprintf.c:969
pointer+0x185/0x970 lib/vsprintf.c:2226
vsnprintf+0x5b2/0x14f0 lib/vsprintf.c:2624
vscnprintf+0x29/0x80 lib/vsprintf.c:2723
vprintk_store+0x44/0x4a0 kernel/printk/printk.c:1942
vprintk_emit+0x139/0x770 kernel/printk/printk.c:2003
vprintk_func+0x8f/0x1a6 kernel/printk/printk_safe.c:393
printk+0xba/0xed kernel/printk/printk.c:2070
show_ip+0x22/0x30 arch/x86/kernel/dumpstack.c:131
show_iret_regs+0x10/0x32 arch/x86/kernel/dumpstack.c:138
__show_regs+0x18/0x50 arch/x86/kernel/process_64.c:72
show_trace_log_lvl+0x255/0x2b4 arch/x86/kernel/dumpstack.c:281
show_regs arch/x86/kernel/dumpstack.c:454 [inline]
__die_body arch/x86/kernel/dumpstack.c:400 [inline]
__die+0x51/0x90 arch/x86/kernel/dumpstack.c:414
no_context+0x56b/0x9f0 arch/x86/mm/fault.c:695
__bad_area_nosemaphore+0xa9/0x480 arch/x86/mm/fault.c:789
do_kern_addr_fault+0x5b/0x6f arch/x86/mm/fault.c:1130
handle_page_fault arch/x86/mm/fault.c:1363 [inline]
exc_page_fault+0x14c/0x170 arch/x86/mm/fault.c:1418
asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:542
RIP: 0010:__syscall_return_slowpath+0x0/0x280 arch/x86/entry/common.c:332
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 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
RSP: 0018:ffffc900015b7f38 EFLAGS: 00010283
RAX: fffffffffffffffe RBX: 0000000000000015 RCX: 1ffff920002b6fd5
RDX: ffff88809d834000 RSI: ffffffff81bcb65f RDI: ffffc900015b7f58
RBP: ffffc900015b7f58 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
do_syscall_64+0x6c/0xe0 arch/x86/entry/common.c:393
entry_SYSCALL_64_after_hwframe+0x44/0xa9
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#3] PREEMPT SMP KASAN
CPU: 1 PID: 3892 Comm: systemd-udevd Not tainted 5.8.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:in_gate_area_no_mm+0x0/0x6a arch/x86/entry/vsyscall/vsyscall_64.c:343
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 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
RSP: 0018:ffffc900015b6990 EFLAGS: 00010093
RAX: 0000000000000000 RBX: ffffc900015b6a30 RCX: ffffffff816a6330
RDX: ffff88809d834000 RSI: ffffffff816a635b RDI: 00007f08629809c7
RBP: 00007f08629809c7 R08: ffffc900015b6b40 R09: ffff8880ae723d62
R10: 00007f08629809c7 R11: 0000000000000001 R12: ffffc900015b6b40
R13: 0000000000000001 R14: 00007f08629809c7 R15: ffffc900015b6a50
FS: 00007f0863b0d8c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000009a278000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
is_kernel include/linux/kallsyms.h:44 [inline]
is_ksym_addr include/linux/kallsyms.h:50 [inline]
kallsyms_lookup+0xc3/0x2e0 kernel/kallsyms.c:290
__sprint_symbol+0x9c/0x1c0 kernel/kallsyms.c:363
symbol_string+0x14c/0x370 lib/vsprintf.c:969
pointer+0x185/0x970 lib/vsprintf.c:2226
vsnprintf+0x5b2/0x14f0 lib/vsprintf.c:2624
vscnprintf+0x29/0x80 lib/vsprintf.c:2723
printk_safe_log_store+0xf5/0x250 kernel/printk/printk_safe.c:94
vprintk_safe kernel/printk/printk_safe.c:347 [inline]
vprintk_func+0xef/0x1a6 kernel/printk/printk_safe.c:390
printk+0xba/0xed kernel/printk/printk.c:2070
show_ip+0x22/0x30 arch/x86/kernel/dumpstack.c:131
show_iret_regs+0x10/0x32 arch/x86/kernel/dumpstack.c:138
__show_regs+0x18/0x50 arch/x86/kernel/process_64.c:72
show_trace_log_lvl+0x255/0x2b4 arch/x86/kernel/dumpstack.c:281
show_regs arch/x86/kernel/dumpstack.c:454 [inline]
__die_body arch/x86/kernel/dumpstack.c:400 [inline]
__die+0x51/0x90 arch/x86/kernel/dumpstack.c:414
no_context+0x56b/0x9f0 arch/x86/mm/fault.c:695
__bad_area_nosemaphore+0xa9/0x480 arch/x86/mm/fault.c:789
do_user_addr_fault+0x783/0xd00 arch/x86/mm/fault.c:1171
handle_page_fault arch/x86/mm/fault.c:1365 [inline]
exc_page_fault+0xab/0x170 arch/x86/mm/fault.c:1418
asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:542
RIP: 0010:in_gate_area_no_mm+0x0/0x6a arch/x86/entry/vsyscall/vsyscall_64.c:343
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 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
RSP: 0018:ffffc900015b74a0 EFLAGS: 00010093
RAX: 0000000000000000 RBX: ffffc900015b7540 RCX: ffffffff816a6330
RDX: ffff88809d834000 RSI: ffffffff816a635b RDI: 00007f08629809c7
RBP: 00007f08629809c7 R08: ffffc900015b7650 R09: ffffffff8c8d7109
R10: 00007f08629809c7 R11: 0000000000000000 R12: ffffc900015b7650
R13: 0000000000000001 R14: 00007f08629809c7 R15: ffffc900015b7560
is_kernel include/linux/kallsyms.h:44 [inline]
is_ksym_addr include/linux/kallsyms.h:50 [inline]
kallsyms_lookup+0xc3/0x2e0 kernel/kallsyms.c:290
__sprint_symbol+0x9c/0x1c0 kernel/kallsyms.c:363
symbol_string+0x14c/0x370 lib/vsprintf.c:969
pointer+0x185/0x970 lib/vsprintf.c:2226
vsnprintf+0x5b2/0x14f0 lib/vsprintf.c:2624
vscnprintf+0x29/0x80 lib/vsprintf.c:2723
vprintk_store+0x44/0x4a0 kernel/printk/printk.c:1942
vprintk_emit+0x139/0x770 kernel/printk/printk.c:2003
vprintk_func+0x8f/0x1a6 kernel/printk/printk_safe.c:393
printk+0xba/0xed kernel/printk/printk.c:2070
show_ip+0x22/0x30 arch/x86/kernel/dumpstack.c:131
show_iret_regs+0x10/0x32 arch/x86/kernel/dumpstack.c:138
__show_regs+0x18/0x50 arch/x86/kernel/process_64.c:72
show_trace_log_lvl+0x255/0x2b4 arch/x86/kernel/dumpstack.c:281
show_regs arch/x86/kernel/dumpstack.c:454 [inline]
__die_body arch/x86/kernel/dumpstack.c:400 [inline]
__die+0x51/0x90 arch/x86/kernel/dumpstack.c:414
no_context+0x56b/0x9f0 arch/x86/mm/fault.c:695
__bad_area_nosemaphore+0xa9/0x480 arch/x86/mm/fault.c:789
do_kern_addr_fault+0x5b/0x6f arch/x86/mm/fault.c:1130
handle_page_fault arch/x86/mm/fault.c:1363 [inline]
exc_page_fault+0x14c/0x170 arch/x86/mm/fault.c:1418
asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:542
RIP: 0010:__syscall_return_slowpath+0x0/0x280 arch/x86/entry/common.c:332
Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Lost 40 message(s)!


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