* [syzbot] [kernel?] general protection fault in proc_sys_call_handler
@ 2025-01-04 1:20 syzbot
2025-01-04 3:10 ` Edward Adam Davis
` (5 more replies)
0 siblings, 6 replies; 12+ messages in thread
From: syzbot @ 2025-01-04 1:20 UTC (permalink / raw)
To: linux-kernel, luto, peterz, syzkaller-bugs, tglx
Hello,
syzbot found the following issue on:
HEAD commit: ccb98ccef0e5 Merge tag 'platform-drivers-x86-v6.13-4' of g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13f1eaf8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=86dd15278dbfe19f
dashboard link: https://syzkaller.appspot.com/bug?extid=2e65930fda17880da336
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=140888b0580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d24eb225cff7/disk-ccb98cce.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/dd81532f8240/vmlinux-ccb98cce.xz
kernel image: https://storage.googleapis.com/syzbot-assets/18b08e4bbf40/bzImage-ccb98cce.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2e65930fda17880da336@syzkaller.appspotmail.com
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 UID: 0 PID: 5943 Comm: syz-executor Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:get_uts kernel/utsname_sysctl.c:23 [inline]
RIP: 0010:proc_do_uts_string+0x137/0x4e0 kernel/utsname_sysctl.c:50
Code: 48 c1 ee 03 80 3c 0e 00 0f 85 56 03 00 00 48 8b 92 08 09 00 00 48 b9 00 00 00 00 00 fc ff df 48 8d 7a 08 48 89 fe 48 c1 ee 03 <80> 3c 0e 00 0f 85 12 03 00 00 48 be 00 00 00 00 00 fc ff df 48 2d
RSP: 0018:ffffc900038f7468 EFLAGS: 00010202
RAX: ffffffff90022485 RBX: 1ffff9200071ee92 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000008
RBP: ffffffff8de39fd8 R08: 0000000000000001 R09: fffffbfff1b8e071
R10: ffffffff8dc7038f R11: 0000000000000002 R12: 0000000000000001
R13: ffffc900038f7520 R14: dffffc0000000000 R15: ffffffff8de39fe0
FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0544972008 CR3: 000000000db7e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
proc_sys_call_handler+0x403/0x5d0 fs/proc/proc_sysctl.c:601
__kernel_write_iter+0x318/0xa80 fs/read_write.c:612
__kernel_write+0xf6/0x140 fs/read_write.c:632
do_acct_process+0xcb0/0x14a0 kernel/acct.c:539
acct_pin_kill+0x2d/0x100 kernel/acct.c:192
pin_kill+0x194/0x7c0 fs/fs_pin.c:44
mnt_pin_kill+0x61/0x1e0 fs/fs_pin.c:81
cleanup_mnt+0x3ac/0x450 fs/namespace.c:1366
task_work_run+0x14e/0x250 kernel/task_work.c:239
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0xad8/0x2d70 kernel/exit.c:938
do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
get_signal+0x2576/0x2610 kernel/signal.c:3017
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f069358473c
Code: Unable to access opcode bytes at 0x7f0693584712.
RSP: 002b:00007ffd01fb5d30 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: fffffffffffffe00 RBX: 0000000000000003 RCX: 00007f069358473c
RDX: 0000000000000030 RSI: 00007ffd01fb5de0 RDI: 00000000000000f9
RBP: 00007ffd01fb5d8c R08: 0000000000000000 R09: 0079746972756365
R10: 00007ffd01fb56f0 R11: 0000000000000246 R12: 0000000000000032
R13: 000000000002bc4a R14: 00007ffd01fb5de0 R15: 0000000000000258
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:get_uts kernel/utsname_sysctl.c:23 [inline]
RIP: 0010:proc_do_uts_string+0x137/0x4e0 kernel/utsname_sysctl.c:50
Code: 48 c1 ee 03 80 3c 0e 00 0f 85 56 03 00 00 48 8b 92 08 09 00 00 48 b9 00 00 00 00 00 fc ff df 48 8d 7a 08 48 89 fe 48 c1 ee 03 <80> 3c 0e 00 0f 85 12 03 00 00 48 be 00 00 00 00 00 fc ff df 48 2d
RSP: 0018:ffffc900038f7468 EFLAGS: 00010202
RAX: ffffffff90022485 RBX: 1ffff9200071ee92 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000008
RBP: ffffffff8de39fd8 R08: 0000000000000001 R09: fffffbfff1b8e071
R10: ffffffff8dc7038f R11: 0000000000000002 R12: 0000000000000001
R13: ffffc900038f7520 R14: dffffc0000000000 R15: ffffffff8de39fe0
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc686ce448 CR3: 000000002f9ae000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 48 c1 ee 03 shr $0x3,%rsi
4: 80 3c 0e 00 cmpb $0x0,(%rsi,%rcx,1)
8: 0f 85 56 03 00 00 jne 0x364
e: 48 8b 92 08 09 00 00 mov 0x908(%rdx),%rdx
15: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx
1c: fc ff df
1f: 48 8d 7a 08 lea 0x8(%rdx),%rdi
23: 48 89 fe mov %rdi,%rsi
26: 48 c1 ee 03 shr $0x3,%rsi
* 2a: 80 3c 0e 00 cmpb $0x0,(%rsi,%rcx,1) <-- trapping instruction
2e: 0f 85 12 03 00 00 jne 0x346
34: 48 be 00 00 00 00 00 movabs $0xdffffc0000000000,%rsi
3b: fc ff df
3e: 48 rex.W
3f: 2d .byte 0x2d
---
This report is generated by a bot. It may contain errors.
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If the report is already addressed, let syzbot know by replying with:
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#syz undup
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [syzbot] [kernel?] general protection fault in proc_sys_call_handler
2025-01-04 1:20 [syzbot] [kernel?] general protection fault in proc_sys_call_handler syzbot
@ 2025-01-04 3:10 ` Edward Adam Davis
2025-01-04 3:25 ` syzbot
2025-01-04 4:32 ` Edward Adam Davis
` (4 subsequent siblings)
5 siblings, 1 reply; 12+ messages in thread
From: Edward Adam Davis @ 2025-01-04 3:10 UTC (permalink / raw)
To: syzbot+2e65930fda17880da336; +Cc: linux-kernel, syzkaller-bugs
utsname: debug ctl table for domainname
Before exit_task_work() is executed, exit_task_namespaces() has been executed,
which will cause task->nsproxy to be NULL.
#syz test: https://github.com/ea1davis/linux proc/syz
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [syzbot] [kernel?] general protection fault in proc_sys_call_handler
2025-01-04 3:10 ` Edward Adam Davis
@ 2025-01-04 3:25 ` syzbot
0 siblings, 0 replies; 12+ messages in thread
From: syzbot @ 2025-01-04 3:25 UTC (permalink / raw)
To: eadavis, linux-kernel, syzkaller-bugs
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
general protection fault in proc_sys_call_handler
tab: ffffffff8de3a458, data: ffffffff90028ec5, procname: domainname, proc_do_uts_string
tab: ffffffff8de3a458, data: ffffffff90028ec5, proc_sys_call_handler
tab: ffffffff8de3a458, data: ffffffff90028ec5, procname: domainname, proc_do_uts_string
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 UID: 0 PID: 6417 Comm: syz-executor Not tainted 6.12.0-syzkaller-10299-gdcb6ff6bb369 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:get_uts kernel/utsname_sysctl.c:23 [inline]
RIP: 0010:proc_do_uts_string+0x1ee/0x5d0 kernel/utsname_sysctl.c:54
Code: 48 c1 ee 03 80 3c 0e 00 0f 85 6a 03 00 00 48 8b 92 08 09 00 00 48 b9 00 00 00 00 00 fc ff df 48 8d 7a 08 48 89 fe 48 c1 ee 03 <80> 3c 0e 00 0f 85 28 03 00 00 48 be 00 00 00 00 00 fc ff df 48 2d
RSP: 0018:ffffc90003657468 EFLAGS: 00010202
RAX: ffffffff90028ec5 RBX: ffffffff8de3a458 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000008
RBP: 1ffff920006cae92 R08: 0000000000000001 R09: fffffbfff1b8e045
R10: ffffffff8dc7022f R11: 0000000000000002 R12: 0000000000000001
R13: ffffc900036574c0 R14: ffffffff8de3a460 R15: ffffc90003657520
FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e8f20af048 CR3: 0000000034d8c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
proc_sys_call_handler+0x441/0x610 fs/proc/proc_sysctl.c:602
__kernel_write_iter+0x318/0xa80 fs/read_write.c:612
__kernel_write+0xf6/0x140 fs/read_write.c:632
do_acct_process+0xcb0/0x14a0 kernel/acct.c:539
acct_pin_kill+0x2d/0x100 kernel/acct.c:192
pin_kill+0x194/0x7c0 fs/fs_pin.c:44
mnt_pin_kill+0x61/0x1e0 fs/fs_pin.c:81
cleanup_mnt+0x3ac/0x450 fs/namespace.c:1366
task_work_run+0x14e/0x250 kernel/task_work.c:239
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0xadd/0x2d70 kernel/exit.c:938
do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
get_signal+0x2576/0x2610 kernel/signal.c:3016
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f47f6787c47
Code: Unable to access opcode bytes at 0x7f47f6787c1d.
RSP: 002b:00007ffe11e12818 EFLAGS: 00000202 ORIG_RAX: 0000000000000029
RAX: 0000000000000003 RBX: 0000000000000003 RCX: 00007f47f6787c47
RDX: 0000000000000006 RSI: 0000000000000001 RDI: 0000000000000002
RBP: 00007ffe11e12efc R08: 00007ffe11e1280c R09: 00007ffe11e12c17
R10: 00007ffe11e12890 R11: 0000000000000202 R12: 0000000000000032
R13: 000000000002677e R14: 00007ffe11e12f50 R15: 0000000000000258
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:get_uts kernel/utsname_sysctl.c:23 [inline]
RIP: 0010:proc_do_uts_string+0x1ee/0x5d0 kernel/utsname_sysctl.c:54
Code: 48 c1 ee 03 80 3c 0e 00 0f 85 6a 03 00 00 48 8b 92 08 09 00 00 48 b9 00 00 00 00 00 fc ff df 48 8d 7a 08 48 89 fe 48 c1 ee 03 <80> 3c 0e 00 0f 85 28 03 00 00 48 be 00 00 00 00 00 fc ff df 48 2d
RSP: 0018:ffffc90003657468 EFLAGS: 00010202
RAX: ffffffff90028ec5 RBX: ffffffff8de3a458 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000008
RBP: 1ffff920006cae92 R08: 0000000000000001 R09: fffffbfff1b8e045
R10: ffffffff8dc7022f R11: 0000000000000002 R12: 0000000000000001
R13: ffffc900036574c0 R14: ffffffff8de3a460 R15: ffffc90003657520
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f27a1ca7d60 CR3: 0000000034d8c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 48 c1 ee 03 shr $0x3,%rsi
4: 80 3c 0e 00 cmpb $0x0,(%rsi,%rcx,1)
8: 0f 85 6a 03 00 00 jne 0x378
e: 48 8b 92 08 09 00 00 mov 0x908(%rdx),%rdx
15: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx
1c: fc ff df
1f: 48 8d 7a 08 lea 0x8(%rdx),%rdi
23: 48 89 fe mov %rdi,%rsi
26: 48 c1 ee 03 shr $0x3,%rsi
* 2a: 80 3c 0e 00 cmpb $0x0,(%rsi,%rcx,1) <-- trapping instruction
2e: 0f 85 28 03 00 00 jne 0x35c
34: 48 be 00 00 00 00 00 movabs $0xdffffc0000000000,%rsi
3b: fc ff df
3e: 48 rex.W
3f: 2d .byte 0x2d
Tested on:
commit: dcb6ff6b utsname: debug ctl table for domainname
git tree: https://github.com/ea1davis/linux proc/syz
console output: https://syzkaller.appspot.com/x/log.txt?x=141938b0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e8d97faf7b870c89
dashboard link: https://syzkaller.appspot.com/bug?extid=2e65930fda17880da336
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Note: no patches were applied.
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [syzbot] [kernel?] general protection fault in proc_sys_call_handler
2025-01-04 1:20 [syzbot] [kernel?] general protection fault in proc_sys_call_handler syzbot
2025-01-04 3:10 ` Edward Adam Davis
@ 2025-01-04 4:32 ` Edward Adam Davis
2025-01-04 4:49 ` syzbot
2025-01-04 5:12 ` Edward Adam Davis
` (3 subsequent siblings)
5 siblings, 1 reply; 12+ messages in thread
From: Edward Adam Davis @ 2025-01-04 4:32 UTC (permalink / raw)
To: syzbot+2e65930fda17880da336; +Cc: linux-kernel, syzkaller-bugs
utsname: debug ctl table for domainname
Before exit_task_work() is executed, exit_task_namespaces() has been executed,
which will cause task->nsproxy to be NULL.
sys_acct accounting records to "/proc/sys/kernel/domainname", if data
too long, can we continue account?
#syz test: https://github.com/ea1davis/linux proc/syz
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [syzbot] [kernel?] general protection fault in proc_sys_call_handler
2025-01-04 4:32 ` Edward Adam Davis
@ 2025-01-04 4:49 ` syzbot
0 siblings, 0 replies; 12+ messages in thread
From: syzbot @ 2025-01-04 4:49 UTC (permalink / raw)
To: eadavis, linux-kernel, syzkaller-bugs
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
general protection fault in proc_sys_call_handler
write buf: \x13\x03, count: 64, tab: ffffffff8de3a458, proc_sys_call_handler
tab: ffffffff8de3a458, data: ffffffff90028f45, w: 1, proc_sys_call_handler
tab: ffffffff8de3a458, data: ffffffff90028f45, datalen: 6, maxlen: 65, procname: domainname, proc_do_uts_string
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 UID: 0 PID: 6507 Comm: syz-executor Not tainted 6.12.0-syzkaller-10299-g85a8463a4d24 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:get_uts kernel/utsname_sysctl.c:23 [inline]
RIP: 0010:proc_do_uts_string+0x1ea/0x5e0 kernel/utsname_sysctl.c:53
Code: 48 c1 ee 03 80 3c 0e 00 0f 85 76 03 00 00 48 8b 92 08 09 00 00 48 b9 00 00 00 00 00 fc ff df 48 8d 7a 08 48 89 fe 48 c1 ee 03 <80> 3c 0e 00 0f 85 32 03 00 00 48 be 00 00 00 00 00 fc ff df 48 2d
RSP: 0018:ffffc90003567460 EFLAGS: 00010202
RAX: ffffffff90028f45 RBX: ffffffff8de3a458 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000008
RBP: 1ffff920006ace92 R08: 0000000000000001 R09: fffffbfff1b8e045
R10: ffffffff8dc7022f R11: 0000000000000002 R12: 0000000000000001
R13: ffffc900035674c0 R14: ffffc90003567520 R15: ffffffff8de3a460
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056128a1406dd CR3: 000000002cf9c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
proc_sys_call_handler+0x4b8/0x700 fs/proc/proc_sysctl.c:607
__kernel_write_iter+0x318/0xa80 fs/read_write.c:612
__kernel_write+0xf6/0x140 fs/read_write.c:632
do_acct_process+0xcb0/0x14a0 kernel/acct.c:539
acct_pin_kill+0x2d/0x100 kernel/acct.c:192
pin_kill+0x194/0x7c0 fs/fs_pin.c:44
mnt_pin_kill+0x61/0x1e0 fs/fs_pin.c:81
cleanup_mnt+0x3ac/0x450 fs/namespace.c:1366
task_work_run+0x14e/0x250 kernel/task_work.c:239
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0xadd/0x2d70 kernel/exit.c:938
do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
get_signal+0x2576/0x2610 kernel/signal.c:3016
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efcf8784597
Code: Unable to access opcode bytes at 0x7efcf878456d.
RSP: 002b:00007ffe839f29c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000102
RAX: 0000000000000000 RBX: 00007ffe839f2a10 RCX: 00007efcf8784597
RDX: 00000000000001ff RSI: 00007ffe839f2a10 RDI: 00000000ffffff9c
RBP: 00007ffe839f29fc R08: 0000000000000005 R09: 00007ffe839f2765
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000032
R13: 000000000002b475 R14: 00007ffe839f2a50 R15: 0000000000000258
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:get_uts kernel/utsname_sysctl.c:23 [inline]
RIP: 0010:proc_do_uts_string+0x1ea/0x5e0 kernel/utsname_sysctl.c:53
Code: 48 c1 ee 03 80 3c 0e 00 0f 85 76 03 00 00 48 8b 92 08 09 00 00 48 b9 00 00 00 00 00 fc ff df 48 8d 7a 08 48 89 fe 48 c1 ee 03 <80> 3c 0e 00 0f 85 32 03 00 00 48 be 00 00 00 00 00 fc ff df 48 2d
RSP: 0018:ffffc90003567460 EFLAGS: 00010202
RAX: ffffffff90028f45 RBX: ffffffff8de3a458 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000008
RBP: 1ffff920006ace92 R08: 0000000000000001 R09: fffffbfff1b8e045
R10: ffffffff8dc7022f R11: 0000000000000002 R12: 0000000000000001
R13: ffffc900035674c0 R14: ffffc90003567520 R15: ffffffff8de3a460
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056128a1406dd CR3: 0000000030060000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 48 c1 ee 03 shr $0x3,%rsi
4: 80 3c 0e 00 cmpb $0x0,(%rsi,%rcx,1)
8: 0f 85 76 03 00 00 jne 0x384
e: 48 8b 92 08 09 00 00 mov 0x908(%rdx),%rdx
15: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx
1c: fc ff df
1f: 48 8d 7a 08 lea 0x8(%rdx),%rdi
23: 48 89 fe mov %rdi,%rsi
26: 48 c1 ee 03 shr $0x3,%rsi
* 2a: 80 3c 0e 00 cmpb $0x0,(%rsi,%rcx,1) <-- trapping instruction
2e: 0f 85 32 03 00 00 jne 0x366
34: 48 be 00 00 00 00 00 movabs $0xdffffc0000000000,%rsi
3b: fc ff df
3e: 48 rex.W
3f: 2d .byte 0x2d
Tested on:
commit: 85a8463a utsname: debug ctl table for domainname
git tree: https://github.com/ea1davis/linux proc/syz
console output: https://syzkaller.appspot.com/x/log.txt?x=16e566f8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e8d97faf7b870c89
dashboard link: https://syzkaller.appspot.com/bug?extid=2e65930fda17880da336
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Note: no patches were applied.
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [syzbot] [kernel?] general protection fault in proc_sys_call_handler
2025-01-04 1:20 [syzbot] [kernel?] general protection fault in proc_sys_call_handler syzbot
2025-01-04 3:10 ` Edward Adam Davis
2025-01-04 4:32 ` Edward Adam Davis
@ 2025-01-04 5:12 ` Edward Adam Davis
2025-01-04 5:27 ` syzbot
2025-01-04 5:39 ` Edward Adam Davis
` (2 subsequent siblings)
5 siblings, 1 reply; 12+ messages in thread
From: Edward Adam Davis @ 2025-01-04 5:12 UTC (permalink / raw)
To: syzbot+2e65930fda17880da336; +Cc: linux-kernel, syzkaller-bugs
utsname: debug ctl table for domainname
Before exit_task_work() is executed, exit_task_namespaces() has been executed,
which will cause task->nsproxy to be NULL.
#syz test: https://github.com/ea1davis/linux proc/syz
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [syzbot] [kernel?] general protection fault in proc_sys_call_handler
2025-01-04 5:12 ` Edward Adam Davis
@ 2025-01-04 5:27 ` syzbot
0 siblings, 0 replies; 12+ messages in thread
From: syzbot @ 2025-01-04 5:27 UTC (permalink / raw)
To: eadavis, linux-kernel, syzkaller-bugs
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
general protection fault in proc_sys_call_handler
write buf: \x13\x03, count: 64, tab: ffffffff8de3a458, proc_sys_call_handler
tab: ffffffff8de3a458, data: ffffffff90028ec5, datalen: 6, maxlen: 65, procname: domainname, proc_do_uts_string
write buf: \x13\x03, count: 64, tab: ffffffff8de3a458, proc_sys_call_handler
tab: ffffffff8de3a458, data: ffffffff90028ec5, datalen: 6, maxlen: 65, procname: domainname, proc_do_uts_string
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000028: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000140-0x0000000000000147]
CPU: 0 UID: 0 PID: 6578 Comm: syz-executor Not tainted 6.12.0-syzkaller-10299-g224ab98542f8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:proc_do_uts_string+0x256/0x630 kernel/utsname_sysctl.c:55
Code: 03 00 00 4d 8b 7f 08 e8 28 b1 fe ff 48 8b 04 24 48 be 00 00 00 00 00 fc ff df 48 2d 80 8d 02 90 4c 01 f8 48 89 c2 48 c1 ea 03 <0f> b6 0c 32 48 8d 50 40 48 89 d7 48 c1 ef 03 0f b6 34 37 48 89 c7
RSP: 0018:ffffc900037f7460 EFLAGS: 00010207
RAX: 0000000000000145 RBX: ffffffff8de3a458 RCX: 1ffff11005cb9121
RDX: 0000000000000028 RSI: dffffc0000000000 RDI: ffff88802e5c8908
RBP: 0000000000000001 R08: 0000000000000001 R09: fffffbfff1b8e045
R10: ffffffff8dc7022f R11: 0000000000000002 R12: ffffc900037f74c0
R13: ffffc900037f7520 R14: ffffffff8de3a460 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556c83033da8 CR3: 0000000030b94000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
proc_sys_call_handler+0x424/0x5f0 fs/proc/proc_sysctl.c:602
__kernel_write_iter+0x318/0xa80 fs/read_write.c:612
__kernel_write+0xf6/0x140 fs/read_write.c:632
do_acct_process+0xcb0/0x14a0 kernel/acct.c:539
acct_pin_kill+0x2d/0x100 kernel/acct.c:192
pin_kill+0x194/0x7c0 fs/fs_pin.c:44
mnt_pin_kill+0x61/0x1e0 fs/fs_pin.c:81
cleanup_mnt+0x3ac/0x450 fs/namespace.c:1366
task_work_run+0x14e/0x250 kernel/task_work.c:239
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0xadd/0x2d70 kernel/exit.c:938
do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
get_signal+0x2576/0x2610 kernel/signal.c:3016
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6c3438498a
Code: Unable to access opcode bytes at 0x7f6c34384960.
RSP: 002b:00007ffe74966a30 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f6c3438498a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007ffe74966a7c R08: 00007ffe7496637c R09: 0079746972756365
R10: 00007ffe749663e0 R11: 0000000000000293 R12: 0000000000000032
R13: 00000000000276a7 R14: 00007ffe74966ad0 R15: 0000000000000258
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:proc_do_uts_string+0x256/0x630 kernel/utsname_sysctl.c:55
Code: 03 00 00 4d 8b 7f 08 e8 28 b1 fe ff 48 8b 04 24 48 be 00 00 00 00 00 fc ff df 48 2d 80 8d 02 90 4c 01 f8 48 89 c2 48 c1 ea 03 <0f> b6 0c 32 48 8d 50 40 48 89 d7 48 c1 ef 03 0f b6 34 37 48 89 c7
RSP: 0018:ffffc900037f7460 EFLAGS: 00010207
RAX: 0000000000000145 RBX: ffffffff8de3a458 RCX: 1ffff11005cb9121
RDX: 0000000000000028 RSI: dffffc0000000000 RDI: ffff88802e5c8908
RBP: 0000000000000001 R08: 0000000000000001 R09: fffffbfff1b8e045
R10: ffffffff8dc7022f R11: 0000000000000002 R12: ffffc900037f74c0
R13: ffffc900037f7520 R14: ffffffff8de3a460 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556c83033da8 CR3: 0000000030b94000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 03 00 add (%rax),%eax
2: 00 4d 8b add %cl,-0x75(%rbp)
5: 7f 08 jg 0xf
7: e8 28 b1 fe ff call 0xfffeb134
c: 48 8b 04 24 mov (%rsp),%rax
10: 48 be 00 00 00 00 00 movabs $0xdffffc0000000000,%rsi
17: fc ff df
1a: 48 2d 80 8d 02 90 sub $0xffffffff90028d80,%rax
20: 4c 01 f8 add %r15,%rax
23: 48 89 c2 mov %rax,%rdx
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 0f b6 0c 32 movzbl (%rdx,%rsi,1),%ecx <-- trapping instruction
2e: 48 8d 50 40 lea 0x40(%rax),%rdx
32: 48 89 d7 mov %rdx,%rdi
35: 48 c1 ef 03 shr $0x3,%rdi
39: 0f b6 34 37 movzbl (%rdi,%rsi,1),%esi
3d: 48 89 c7 mov %rax,%rdi
Tested on:
commit: 224ab985 utsname: debug ctl table for domainname
git tree: https://github.com/ea1davis/linux proc/syz
console output: https://syzkaller.appspot.com/x/log.txt?x=106b38b0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e8d97faf7b870c89
dashboard link: https://syzkaller.appspot.com/bug?extid=2e65930fda17880da336
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Note: no patches were applied.
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [syzbot] [kernel?] general protection fault in proc_sys_call_handler
2025-01-04 1:20 [syzbot] [kernel?] general protection fault in proc_sys_call_handler syzbot
` (2 preceding siblings ...)
2025-01-04 5:12 ` Edward Adam Davis
@ 2025-01-04 5:39 ` Edward Adam Davis
2025-01-04 5:54 ` syzbot
2025-01-04 6:00 ` Edward Adam Davis
2025-01-04 12:21 ` [PATCH] utsname: Prevents using NULL value nsproxy Edward Adam Davis
5 siblings, 1 reply; 12+ messages in thread
From: Edward Adam Davis @ 2025-01-04 5:39 UTC (permalink / raw)
To: syzbot+2e65930fda17880da336; +Cc: linux-kernel, syzkaller-bugs
utsname: debug ctl table for domainname
Before exit_task_work() is executed, exit_task_namespaces() has been executed,
which will cause task->nsproxy to be NULL.
#syz test: https://github.com/ea1davis/linux proc/syz
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: [syzbot] [kernel?] general protection fault in proc_sys_call_handler
2025-01-04 5:39 ` Edward Adam Davis
@ 2025-01-04 5:54 ` syzbot
0 siblings, 0 replies; 12+ messages in thread
From: syzbot @ 2025-01-04 5:54 UTC (permalink / raw)
To: eadavis, linux-kernel, syzkaller-bugs
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
general protection fault in proc_sys_call_handler
nsp: ffff888032f4d340, get_uts
nsp: ffff888032f4d340, get_uts
write buf: \x13\x03, count: 64, tab: ffffffff8de3a458, proc_sys_call_handler
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000028: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000140-0x0000000000000147]
CPU: 0 UID: 0 PID: 6593 Comm: syz-executor Not tainted 6.12.0-syzkaller-10299-g5009ba366804 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:proc_do_uts_string+0x1f1/0x610 kernel/utsname_sysctl.c:54
Code: 03 00 00 4d 8b 76 08 e8 8d b1 fe ff 48 8b 04 24 48 be 00 00 00 00 00 fc ff df 48 2d 80 8d 02 90 4c 01 f0 48 89 c2 48 c1 ea 03 <0f> b6 0c 32 48 8d 50 40 48 89 d7 48 c1 ef 03 0f b6 34 37 48 89 c7
RSP: 0018:ffffc90003e6f468 EFLAGS: 00010207
RAX: 0000000000000145 RBX: 1ffff920007cde92 RCX: 1ffff110052538a1
RDX: 0000000000000028 RSI: dffffc0000000000 RDI: ffff88802929c508
RBP: ffffffff8de3a458 R08: 0000000000000001 R09: fffffbfff1b8e045
R10: ffffffff8dc7022f R11: 0000000000000002 R12: 0000000000000001
R13: ffffc90003e6f520 R14: 0000000000000000 R15: ffffffff8de3a460
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562a01053200 CR3: 000000007a9a2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
proc_sys_call_handler+0x424/0x5f0 fs/proc/proc_sysctl.c:602
__kernel_write_iter+0x318/0xa80 fs/read_write.c:612
__kernel_write+0xf6/0x140 fs/read_write.c:632
do_acct_process+0xcb0/0x14a0 kernel/acct.c:539
acct_pin_kill+0x2d/0x100 kernel/acct.c:192
pin_kill+0x194/0x7c0 fs/fs_pin.c:44
mnt_pin_kill+0x61/0x1e0 fs/fs_pin.c:81
cleanup_mnt+0x3ac/0x450 fs/namespace.c:1366
task_work_run+0x14e/0x250 kernel/task_work.c:239
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0xadd/0x2d70 kernel/exit.c:938
do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
get_signal+0x2576/0x2610 kernel/signal.c:3016
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f810a587a6a
Code: Unable to access opcode bytes at 0x7f810a587a40.
RSP: 002b:00007ffcd4dfd8c8 EFLAGS: 00000212 ORIG_RAX: 0000000000000037
RAX: 0000000000000000 RBX: 00007ffcd4dfd950 RCX: 00007f810a587a6a
RDX: 0000000000000041 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007ffcd4dfd8ec R09: 0079746972756365
R10: 00007ffcd4dfd950 R11: 0000000000000212 R12: 00007f810a747a00
R13: 00007ffcd4dfd8ec R14: 0000000000000000 R15: 00007f810a748e40
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:proc_do_uts_string+0x1f1/0x610 kernel/utsname_sysctl.c:54
Code: 03 00 00 4d 8b 76 08 e8 8d b1 fe ff 48 8b 04 24 48 be 00 00 00 00 00 fc ff df 48 2d 80 8d 02 90 4c 01 f0 48 89 c2 48 c1 ea 03 <0f> b6 0c 32 48 8d 50 40 48 89 d7 48 c1 ef 03 0f b6 34 37 48 89 c7
RSP: 0018:ffffc90003e6f468 EFLAGS: 00010207
RAX: 0000000000000145 RBX: 1ffff920007cde92 RCX: 1ffff110052538a1
RDX: 0000000000000028 RSI: dffffc0000000000 RDI: ffff88802929c508
RBP: ffffffff8de3a458 R08: 0000000000000001 R09: fffffbfff1b8e045
R10: ffffffff8dc7022f R11: 0000000000000002 R12: 0000000000000001
R13: ffffc90003e6f520 R14: 0000000000000000 R15: ffffffff8de3a460
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562a00fcac40 CR3: 000000007c1d4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 03 00 add (%rax),%eax
2: 00 4d 8b add %cl,-0x75(%rbp)
5: 76 08 jbe 0xf
7: e8 8d b1 fe ff call 0xfffeb199
c: 48 8b 04 24 mov (%rsp),%rax
10: 48 be 00 00 00 00 00 movabs $0xdffffc0000000000,%rsi
17: fc ff df
1a: 48 2d 80 8d 02 90 sub $0xffffffff90028d80,%rax
20: 4c 01 f0 add %r14,%rax
23: 48 89 c2 mov %rax,%rdx
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 0f b6 0c 32 movzbl (%rdx,%rsi,1),%ecx <-- trapping instruction
2e: 48 8d 50 40 lea 0x40(%rax),%rdx
32: 48 89 d7 mov %rdx,%rdi
35: 48 c1 ef 03 shr $0x3,%rdi
39: 0f b6 34 37 movzbl (%rdi,%rsi,1),%esi
3d: 48 89 c7 mov %rax,%rdi
Tested on:
commit: 5009ba36 utsname: debug ctl table for domainname
git tree: https://github.com/ea1davis/linux proc/syz
console output: https://syzkaller.appspot.com/x/log.txt?x=123366f8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=e8d97faf7b870c89
dashboard link: https://syzkaller.appspot.com/bug?extid=2e65930fda17880da336
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
Note: no patches were applied.
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [syzbot] [kernel?] general protection fault in proc_sys_call_handler
2025-01-04 1:20 [syzbot] [kernel?] general protection fault in proc_sys_call_handler syzbot
` (3 preceding siblings ...)
2025-01-04 5:39 ` Edward Adam Davis
@ 2025-01-04 6:00 ` Edward Adam Davis
2025-01-04 6:21 ` syzbot
2025-01-04 12:21 ` [PATCH] utsname: Prevents using NULL value nsproxy Edward Adam Davis
5 siblings, 1 reply; 12+ messages in thread
From: Edward Adam Davis @ 2025-01-04 6:00 UTC (permalink / raw)
To: syzbot+2e65930fda17880da336; +Cc: linux-kernel, syzkaller-bugs
utsname: debug ctl table for domainname
Before exit_task_work() is executed, exit_task_namespaces() has been executed,
which will cause task->nsproxy to be NULL.
#syz test: https://github.com/ea1davis/linux proc/syz
^ permalink raw reply [flat|nested] 12+ messages in thread* [PATCH] utsname: Prevents using NULL value nsproxy
2025-01-04 1:20 [syzbot] [kernel?] general protection fault in proc_sys_call_handler syzbot
` (4 preceding siblings ...)
2025-01-04 6:00 ` Edward Adam Davis
@ 2025-01-04 12:21 ` Edward Adam Davis
5 siblings, 0 replies; 12+ messages in thread
From: Edward Adam Davis @ 2025-01-04 12:21 UTC (permalink / raw)
To: syzbot+2e65930fda17880da336
Cc: linux-kernel, luto, peterz, syzkaller-bugs, tglx
syzbot reported a null-ptr-deref in get_uts. [1]
Before exit_task_work() is executed, exit_task_namespaces() has been executed,
which will cause task->nsproxy to be NULL.
To avoid this issue, check nsproxy of the task in proc_do_uts_string().
[1]
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 UID: 0 PID: 5943 Comm: syz-executor Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:get_uts kernel/utsname_sysctl.c:23 [inline]
RIP: 0010:proc_do_uts_string+0x137/0x4e0 kernel/utsname_sysctl.c:50
Code: 48 c1 ee 03 80 3c 0e 00 0f 85 56 03 00 00 48 8b 92 08 09 00 00 48 b9 00 00 00 00 00 fc ff df 48 8d 7a 08 48 89 fe 48 c1 ee 03 <80> 3c 0e 00 0f 85 12 03 00 00 48 be 00 00 00 00 00 fc ff df 48 2d
RSP: 0018:ffffc900038f7468 EFLAGS: 00010202
RAX: ffffffff90022485 RBX: 1ffff9200071ee92 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000008
RBP: ffffffff8de39fd8 R08: 0000000000000001 R09: fffffbfff1b8e071
R10: ffffffff8dc7038f R11: 0000000000000002 R12: 0000000000000001
R13: ffffc900038f7520 R14: dffffc0000000000 R15: ffffffff8de39fe0
FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0544972008 CR3: 000000000db7e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
proc_sys_call_handler+0x403/0x5d0 fs/proc/proc_sysctl.c:601
__kernel_write_iter+0x318/0xa80 fs/read_write.c:612
__kernel_write+0xf6/0x140 fs/read_write.c:632
do_acct_process+0xcb0/0x14a0 kernel/acct.c:539
acct_pin_kill+0x2d/0x100 kernel/acct.c:192
pin_kill+0x194/0x7c0 fs/fs_pin.c:44
mnt_pin_kill+0x61/0x1e0 fs/fs_pin.c:81
cleanup_mnt+0x3ac/0x450 fs/namespace.c:1366
task_work_run+0x14e/0x250 kernel/task_work.c:239
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0xad8/0x2d70 kernel/exit.c:938
do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
get_signal+0x2576/0x2610 kernel/signal.c:3017
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
Reported-by: syzbot+2e65930fda17880da336@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=2e65930fda17880da336
Tested-by: syzbot+2e65930fda17880da336@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
---
kernel/utsname_sysctl.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/kernel/utsname_sysctl.c b/kernel/utsname_sysctl.c
index 7282f61a8650..da2a9c92227f 100644
--- a/kernel/utsname_sysctl.c
+++ b/kernel/utsname_sysctl.c
@@ -37,6 +37,9 @@ static int proc_do_uts_string(const struct ctl_table *table, int write,
int r;
char tmp_data[__NEW_UTS_LEN + 1];
+ if (!current->nsproxy)
+ return -EINVAL;
+
memcpy(&uts_table, table, sizeof(uts_table));
uts_table.data = tmp_data;
--
2.47.0
^ permalink raw reply related [flat|nested] 12+ messages in thread
end of thread, other threads:[~2025-01-04 12:32 UTC | newest]
Thread overview: 12+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-01-04 1:20 [syzbot] [kernel?] general protection fault in proc_sys_call_handler syzbot
2025-01-04 3:10 ` Edward Adam Davis
2025-01-04 3:25 ` syzbot
2025-01-04 4:32 ` Edward Adam Davis
2025-01-04 4:49 ` syzbot
2025-01-04 5:12 ` Edward Adam Davis
2025-01-04 5:27 ` syzbot
2025-01-04 5:39 ` Edward Adam Davis
2025-01-04 5:54 ` syzbot
2025-01-04 6:00 ` Edward Adam Davis
2025-01-04 6:21 ` syzbot
2025-01-04 12:21 ` [PATCH] utsname: Prevents using NULL value nsproxy Edward Adam Davis
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