* [syzbot] WARNING in change_protection
@ 2022-09-30 5:56 syzbot
2022-09-30 23:42 ` Andrew Morton
0 siblings, 1 reply; 5+ messages in thread
From: syzbot @ 2022-09-30 5:56 UTC (permalink / raw)
To: akpm, linux-kernel, linux-mm, syzkaller-bugs
Hello,
syzbot found the following issue on:
HEAD commit: 511cce163b75 Merge tag 'net-6.0-rc8' of git://git.kernel.o..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=135cf5c4880000
kernel config: https://syzkaller.appspot.com/x/.config?x=a1992c90769e07
dashboard link: https://syzkaller.appspot.com/bug?extid=2b9b4f0895be09a6dec3
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1164d0ec880000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15c3c2e0880000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2b9b4f0895be09a6dec3@syzkaller.appspotmail.com
------------[ cut here ]------------
WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 make_pte_marker_entry include/linux/swapops.h:323 [inline]
WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 make_pte_marker include/linux/swapops.h:346 [inline]
WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_pte_range mm/mprotect.c:270 [inline]
WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_pmd_range mm/mprotect.c:409 [inline]
WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_pud_range mm/mprotect.c:438 [inline]
WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_p4d_range mm/mprotect.c:459 [inline]
WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_protection_range mm/mprotect.c:483 [inline]
WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_protection+0x16e9/0x4280 mm/mprotect.c:505
Modules linked in:
CPU: 1 PID: 3612 Comm: syz-executor181 Not tainted 6.0.0-rc7-syzkaller-00130-g511cce163b75 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
RIP: 0010:make_pte_marker_entry include/linux/swapops.h:323 [inline]
RIP: 0010:make_pte_marker include/linux/swapops.h:346 [inline]
RIP: 0010:change_pte_range mm/mprotect.c:270 [inline]
RIP: 0010:change_pmd_range mm/mprotect.c:409 [inline]
RIP: 0010:change_pud_range mm/mprotect.c:438 [inline]
RIP: 0010:change_p4d_range mm/mprotect.c:459 [inline]
RIP: 0010:change_protection_range mm/mprotect.c:483 [inline]
RIP: 0010:change_protection+0x16e9/0x4280 mm/mprotect.c:505
Code: ff 48 8b 84 24 90 00 00 00 80 38 00 0f 85 25 29 00 00 48 8b 44 24 10 48 83 b8 90 00 00 00 00 0f 84 8f f9 ff ff e8 a7 d6 c3 ff <0f> 0b 48 ba 00 00 00 00 00 fc ff df 48 8b 04 24 48 c1 e8 03 80 3c
RSP: 0018:ffffc90002fbf968 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000000000
RDX: ffff888073714180 RSI: ffffffff81b76079 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8880000001e8 R14: 0000000000000000 R15: 000000002063e000
FS: 000055555624d300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000005d84c8 CR3: 000000007c916000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
uffd_wp_range+0xf0/0x180 mm/userfaultfd.c:718
mwriteprotect_range+0x2ea/0x420 mm/userfaultfd.c:768
userfaultfd_writeprotect fs/userfaultfd.c:1827 [inline]
userfaultfd_ioctl+0x438/0x43a0 fs/userfaultfd.c:1999
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f77d7707bb9
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe74be7168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f77d7707bb9
RDX: 00000000200000c0 RSI: 00000000c018aa06 RDI: 0000000000000003
RBP: 00007f77d76cbd60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f77d76cbdf0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [syzbot] WARNING in change_protection
2022-09-30 5:56 [syzbot] WARNING in change_protection syzbot
@ 2022-09-30 23:42 ` Andrew Morton
2022-10-01 1:03 ` Peter Xu
0 siblings, 1 reply; 5+ messages in thread
From: Andrew Morton @ 2022-09-30 23:42 UTC (permalink / raw)
To: syzbot
Cc: linux-kernel, linux-mm, syzkaller-bugs, Edward Liaw,
Axel Rasmussen, Peter Xu, Liu Shixin, Brian Geffon, Mike Kravetz
On Thu, 29 Sep 2022 22:56:38 -0700 syzbot <syzbot+2b9b4f0895be09a6dec3@syzkaller.appspotmail.com> wrote:
> Hello,
Thanks. Let's cc a few userfaultfd people.
> syzbot found the following issue on:
>
> HEAD commit: 511cce163b75 Merge tag 'net-6.0-rc8' of git://git.kernel.o..
> git tree: upstream
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=135cf5c4880000
> kernel config: https://syzkaller.appspot.com/x/.config?x=a1992c90769e07
> dashboard link: https://syzkaller.appspot.com/bug?extid=2b9b4f0895be09a6dec3
> compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1164d0ec880000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15c3c2e0880000
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+2b9b4f0895be09a6dec3@syzkaller.appspotmail.com
>
> ------------[ cut here ]------------
> WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 make_pte_marker_entry include/linux/swapops.h:323 [inline]
> WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 make_pte_marker include/linux/swapops.h:346 [inline]
> WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_pte_range mm/mprotect.c:270 [inline]
> WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_pmd_range mm/mprotect.c:409 [inline]
> WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_pud_range mm/mprotect.c:438 [inline]
> WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_p4d_range mm/mprotect.c:459 [inline]
> WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_protection_range mm/mprotect.c:483 [inline]
> WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_protection+0x16e9/0x4280 mm/mprotect.c:505
> Modules linked in:
> CPU: 1 PID: 3612 Comm: syz-executor181 Not tainted 6.0.0-rc7-syzkaller-00130-g511cce163b75 #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
> RIP: 0010:make_pte_marker_entry include/linux/swapops.h:323 [inline]
> RIP: 0010:make_pte_marker include/linux/swapops.h:346 [inline]
> RIP: 0010:change_pte_range mm/mprotect.c:270 [inline]
> RIP: 0010:change_pmd_range mm/mprotect.c:409 [inline]
> RIP: 0010:change_pud_range mm/mprotect.c:438 [inline]
> RIP: 0010:change_p4d_range mm/mprotect.c:459 [inline]
> RIP: 0010:change_protection_range mm/mprotect.c:483 [inline]
> RIP: 0010:change_protection+0x16e9/0x4280 mm/mprotect.c:505
> Code: ff 48 8b 84 24 90 00 00 00 80 38 00 0f 85 25 29 00 00 48 8b 44 24 10 48 83 b8 90 00 00 00 00 0f 84 8f f9 ff ff e8 a7 d6 c3 ff <0f> 0b 48 ba 00 00 00 00 00 fc ff df 48 8b 04 24 48 c1 e8 03 80 3c
> RSP: 0018:ffffc90002fbf968 EFLAGS: 00010293
> RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000000000
> RDX: ffff888073714180 RSI: ffffffff81b76079 RDI: 0000000000000007
> RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
> R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000000
> R13: ffff8880000001e8 R14: 0000000000000000 R15: 000000002063e000
> FS: 000055555624d300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00000000005d84c8 CR3: 000000007c916000 CR4: 00000000003506e0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> <TASK>
> uffd_wp_range+0xf0/0x180 mm/userfaultfd.c:718
> mwriteprotect_range+0x2ea/0x420 mm/userfaultfd.c:768
> userfaultfd_writeprotect fs/userfaultfd.c:1827 [inline]
> userfaultfd_ioctl+0x438/0x43a0 fs/userfaultfd.c:1999
> vfs_ioctl fs/ioctl.c:51 [inline]
> __do_sys_ioctl fs/ioctl.c:870 [inline]
> __se_sys_ioctl fs/ioctl.c:856 [inline]
> __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
> do_syscall_x64 arch/x86/entry/common.c:50 [inline]
> do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
> entry_SYSCALL_64_after_hwframe+0x63/0xcd
> RIP: 0033:0x7f77d7707bb9
> Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007ffe74be7168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f77d7707bb9
> RDX: 00000000200000c0 RSI: 00000000c018aa06 RDI: 0000000000000003
> RBP: 00007f77d76cbd60 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 00007f77d76cbdf0
> R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
> </TASK>
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> syzbot can test patches for this issue, for details see:
> https://goo.gl/tpsmEJ#testing-patches
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [syzbot] WARNING in change_protection
2022-09-30 23:42 ` Andrew Morton
@ 2022-10-01 1:03 ` Peter Xu
2022-10-01 1:14 ` Andrew Morton
0 siblings, 1 reply; 5+ messages in thread
From: Peter Xu @ 2022-10-01 1:03 UTC (permalink / raw)
To: Andrew Morton
Cc: syzbot, linux-kernel, linux-mm, syzkaller-bugs, Edward Liaw,
Axel Rasmussen, Liu Shixin, Brian Geffon, Mike Kravetz
[-- Attachment #1: Type: text/plain, Size: 5565 bytes --]
On Fri, Sep 30, 2022 at 04:42:11PM -0700, Andrew Morton wrote:
> On Thu, 29 Sep 2022 22:56:38 -0700 syzbot <syzbot+2b9b4f0895be09a6dec3@syzkaller.appspotmail.com> wrote:
>
> > Hello,
>
> Thanks. Let's cc a few userfaultfd people.
I remembered there was a similar report and there might have a patch
already, but I can't find it. The timing is a bit unfortunate..
Anyway, a new patch is attached, and I verified it with the reproducer this
time. Thanks,
>
> > syzbot found the following issue on:
> >
> > HEAD commit: 511cce163b75 Merge tag 'net-6.0-rc8' of git://git.kernel.o..
> > git tree: upstream
> > console+strace: https://syzkaller.appspot.com/x/log.txt?x=135cf5c4880000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=a1992c90769e07
> > dashboard link: https://syzkaller.appspot.com/bug?extid=2b9b4f0895be09a6dec3
> > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
> > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1164d0ec880000
> > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15c3c2e0880000
> >
> > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > Reported-by: syzbot+2b9b4f0895be09a6dec3@syzkaller.appspotmail.com
> >
> > ------------[ cut here ]------------
> > WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 make_pte_marker_entry include/linux/swapops.h:323 [inline]
> > WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 make_pte_marker include/linux/swapops.h:346 [inline]
> > WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_pte_range mm/mprotect.c:270 [inline]
> > WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_pmd_range mm/mprotect.c:409 [inline]
> > WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_pud_range mm/mprotect.c:438 [inline]
> > WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_p4d_range mm/mprotect.c:459 [inline]
> > WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_protection_range mm/mprotect.c:483 [inline]
> > WARNING: CPU: 1 PID: 3612 at include/linux/swapops.h:323 change_protection+0x16e9/0x4280 mm/mprotect.c:505
> > Modules linked in:
> > CPU: 1 PID: 3612 Comm: syz-executor181 Not tainted 6.0.0-rc7-syzkaller-00130-g511cce163b75 #0
> > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
> > RIP: 0010:make_pte_marker_entry include/linux/swapops.h:323 [inline]
> > RIP: 0010:make_pte_marker include/linux/swapops.h:346 [inline]
> > RIP: 0010:change_pte_range mm/mprotect.c:270 [inline]
> > RIP: 0010:change_pmd_range mm/mprotect.c:409 [inline]
> > RIP: 0010:change_pud_range mm/mprotect.c:438 [inline]
> > RIP: 0010:change_p4d_range mm/mprotect.c:459 [inline]
> > RIP: 0010:change_protection_range mm/mprotect.c:483 [inline]
> > RIP: 0010:change_protection+0x16e9/0x4280 mm/mprotect.c:505
> > Code: ff 48 8b 84 24 90 00 00 00 80 38 00 0f 85 25 29 00 00 48 8b 44 24 10 48 83 b8 90 00 00 00 00 0f 84 8f f9 ff ff e8 a7 d6 c3 ff <0f> 0b 48 ba 00 00 00 00 00 fc ff df 48 8b 04 24 48 c1 e8 03 80 3c
> > RSP: 0018:ffffc90002fbf968 EFLAGS: 00010293
> > RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000000000
> > RDX: ffff888073714180 RSI: ffffffff81b76079 RDI: 0000000000000007
> > RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
> > R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000000
> > R13: ffff8880000001e8 R14: 0000000000000000 R15: 000000002063e000
> > FS: 000055555624d300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
> > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > CR2: 00000000005d84c8 CR3: 000000007c916000 CR4: 00000000003506e0
> > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> > Call Trace:
> > <TASK>
> > uffd_wp_range+0xf0/0x180 mm/userfaultfd.c:718
> > mwriteprotect_range+0x2ea/0x420 mm/userfaultfd.c:768
> > userfaultfd_writeprotect fs/userfaultfd.c:1827 [inline]
> > userfaultfd_ioctl+0x438/0x43a0 fs/userfaultfd.c:1999
> > vfs_ioctl fs/ioctl.c:51 [inline]
> > __do_sys_ioctl fs/ioctl.c:870 [inline]
> > __se_sys_ioctl fs/ioctl.c:856 [inline]
> > __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
> > do_syscall_x64 arch/x86/entry/common.c:50 [inline]
> > do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
> > entry_SYSCALL_64_after_hwframe+0x63/0xcd
> > RIP: 0033:0x7f77d7707bb9
> > Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
> > RSP: 002b:00007ffe74be7168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> > RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f77d7707bb9
> > RDX: 00000000200000c0 RSI: 00000000c018aa06 RDI: 0000000000000003
> > RBP: 00007f77d76cbd60 R08: 0000000000000000 R09: 0000000000000000
> > R10: 0000000000000000 R11: 0000000000000246 R12: 00007f77d76cbdf0
> > R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
> > </TASK>
> >
> >
> > ---
> > This report is generated by a bot. It may contain errors.
> > See https://goo.gl/tpsmEJ for more information about syzbot.
> > syzbot engineers can be reached at syzkaller@googlegroups.com.
> >
> > syzbot will keep track of this issue. See:
> > https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> > syzbot can test patches for this issue, for details see:
> > https://goo.gl/tpsmEJ#testing-patches
>
--
Peter Xu
[-- Attachment #2: 0001-mm-uffd-Fix-warning-without-PTE_MARKER_UFFD_WP-compi.patch --]
[-- Type: text/plain, Size: 3224 bytes --]
From f965f8879301a5cb04b5b1ca91cb8852b9c17237 Mon Sep 17 00:00:00 2001
From: Peter Xu <peterx@redhat.com>
Date: Fri, 30 Sep 2022 20:25:55 -0400
Subject: [PATCH] mm/uffd: Fix warning without PTE_MARKER_UFFD_WP compiled in
Content-type: text/plain
When PTE_MARKER_UFFD_WP not configured, it's still possible to reach pte
marker code and trigger an warning. Add a few CONFIG_PTE_MARKER_UFFD_WP
ifdefs to make sure the code won't be reached when not compiled in.
Reported-by: syzbot+2b9b4f0895be09a6dec3@syzkaller.appspotmail.com
Signed-off-by: Peter Xu <peterx@redhat.com>
---
mm/hugetlb.c | 4 ++++
mm/memory.c | 2 ++
mm/mprotect.c | 2 ++
3 files changed, 8 insertions(+)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 0bdfc7e1c933..dd29cba46e9e 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -5059,6 +5059,7 @@ static void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct
* unmapped and its refcount is dropped, so just clear pte here.
*/
if (unlikely(!pte_present(pte))) {
+#ifdef CONFIG_PTE_MARKER_UFFD_WP
/*
* If the pte was wr-protected by uffd-wp in any of the
* swap forms, meanwhile the caller does not want to
@@ -5070,6 +5071,7 @@ static void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct
set_huge_pte_at(mm, address, ptep,
make_pte_marker(PTE_MARKER_UFFD_WP));
else
+#endif
huge_pte_clear(mm, address, ptep, sz);
spin_unlock(ptl);
continue;
@@ -5098,11 +5100,13 @@ static void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct
tlb_remove_huge_tlb_entry(h, tlb, ptep, address);
if (huge_pte_dirty(pte))
set_page_dirty(page);
+#ifdef CONFIG_PTE_MARKER_UFFD_WP
/* Leave a uffd-wp pte marker if needed */
if (huge_pte_uffd_wp(pte) &&
!(zap_flags & ZAP_FLAG_DROP_MARKER))
set_huge_pte_at(mm, address, ptep,
make_pte_marker(PTE_MARKER_UFFD_WP));
+#endif
hugetlb_count_sub(pages_per_huge_page(h), mm);
page_remove_rmap(page, vma, true);
diff --git a/mm/memory.c b/mm/memory.c
index a78814413ac0..de0dbe09b013 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1393,10 +1393,12 @@ zap_install_uffd_wp_if_needed(struct vm_area_struct *vma,
unsigned long addr, pte_t *pte,
struct zap_details *details, pte_t pteval)
{
+#ifdef CONFIG_PTE_MARKER_UFFD_WP
if (zap_drop_file_uffd_wp(details))
return;
pte_install_uffd_wp_if_needed(vma, addr, pte, pteval);
+#endif
}
static unsigned long zap_pte_range(struct mmu_gather *tlb,
diff --git a/mm/mprotect.c b/mm/mprotect.c
index bc6bddd156ca..51e7dbd26b6a 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -260,6 +260,7 @@ static unsigned long change_pte_range(struct mmu_gather *tlb,
} else {
/* It must be an none page, or what else?.. */
WARN_ON_ONCE(!pte_none(oldpte));
+#ifdef CONFIG_PTE_MARKER_UFFD_WP
if (unlikely(uffd_wp && !vma_is_anonymous(vma))) {
/*
* For file-backed mem, we need to be able to
@@ -271,6 +272,7 @@ static unsigned long change_pte_range(struct mmu_gather *tlb,
make_pte_marker(PTE_MARKER_UFFD_WP));
pages++;
}
+#endif
}
} while (pte++, addr += PAGE_SIZE, addr != end);
arch_leave_lazy_mmu_mode();
--
2.37.3
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [syzbot] WARNING in change_protection
2022-10-01 1:03 ` Peter Xu
@ 2022-10-01 1:14 ` Andrew Morton
2022-10-01 1:23 ` Peter Xu
0 siblings, 1 reply; 5+ messages in thread
From: Andrew Morton @ 2022-10-01 1:14 UTC (permalink / raw)
To: Peter Xu
Cc: syzbot, linux-kernel, linux-mm, syzkaller-bugs, Edward Liaw,
Axel Rasmussen, Liu Shixin, Brian Geffon, Mike Kravetz
On Fri, 30 Sep 2022 21:03:53 -0400 Peter Xu <peterx@redhat.com> wrote:
> When PTE_MARKER_UFFD_WP not configured, it's still possible to reach pte
> marker code and trigger an warning. Add a few CONFIG_PTE_MARKER_UFFD_WP
> ifdefs to make sure the code won't be reached when not compiled in.
Thanks.
Is 679d10331910180 ("mm: introduce PTE_MARKER swap entry") the
appropriate Fixes: target?
Should we backport to -stable?
The inlined ifdefs are unpleasing. Let's go with this for now, but
some future cleanup would be nice.
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [syzbot] WARNING in change_protection
2022-10-01 1:14 ` Andrew Morton
@ 2022-10-01 1:23 ` Peter Xu
0 siblings, 0 replies; 5+ messages in thread
From: Peter Xu @ 2022-10-01 1:23 UTC (permalink / raw)
To: Andrew Morton
Cc: syzbot, linux-kernel, linux-mm, syzkaller-bugs, Edward Liaw,
Axel Rasmussen, Liu Shixin, Brian Geffon, Mike Kravetz
On Fri, Sep 30, 2022 at 06:14:15PM -0700, Andrew Morton wrote:
> On Fri, 30 Sep 2022 21:03:53 -0400 Peter Xu <peterx@redhat.com> wrote:
>
> > When PTE_MARKER_UFFD_WP not configured, it's still possible to reach pte
> > marker code and trigger an warning. Add a few CONFIG_PTE_MARKER_UFFD_WP
> > ifdefs to make sure the code won't be reached when not compiled in.
>
> Thanks.
>
> Is 679d10331910180 ("mm: introduce PTE_MARKER swap entry") the
> appropriate Fixes: target?
I forgot the stable notations, sorry. Probably better use the one that
enables the whole thing, because the diff will touch a few patches later
than 679d10331910180 too, which means the suitable tag could be:
Fixes: b1f9e876862d ("mm/uffd: enable write protection for shmem & hugetlbfs")
>
> Should we backport to -stable?
Yes, 5.19 may need it too (if it'll still squeeze into 6.0; or 6.0 too).
--
Peter Xu
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2022-10-01 1:26 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-09-30 5:56 [syzbot] WARNING in change_protection syzbot
2022-09-30 23:42 ` Andrew Morton
2022-10-01 1:03 ` Peter Xu
2022-10-01 1:14 ` Andrew Morton
2022-10-01 1:23 ` Peter Xu
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