[syzbot] kernel BUG in process_one_work

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4fafd96910ad Add linux-next specific files for 20230203
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=17e5d623480000
kernel config: https://syzkaller.appspot.com/x/.config?x=1d2fba7d42502ca4
dashboard link: https://syzkaller.appspot.com/bug?extid=c0998868487c1f7e05e5
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=148901bb480000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14911ba5480000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/348cc2da441a/disk-4fafd969.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e2dedc500f12/vmlinux-4fafd969.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fae710d9ebd8/bzImage-4fafd969.xz

The issue was bisected to:

commit 920756a3306a35f1c08f25207d375885bef98975
Author: David Howells <dhow...@redhat.com>
Date: Sat Jan 21 12:51:18 2023 +0000

block: Convert bio_iov_iter_get_pages to use iov_iter_extract_pages

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=13d93dd9480000
final oops: https://syzkaller.appspot.com/x/report.txt?x=10393dd9480000
console output: https://syzkaller.appspot.com/x/log.txt?x=17d93dd9480000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c09988...@syzkaller.appspotmail.com
Fixes: 920756a3306a ("block: Convert bio_iov_iter_get_pages to use iov_iter_extract_pages")

skbuff: skb_over_panic: text:ffffffff8615b76f len:20 put:20 head:0000000000000000 data:0000000000000000 tail:0x14 end:0x0 dev:<NULL>
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:122!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 26 Comm: kworker/1:1 Not tainted 6.2.0-rc6-next-20230203-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:skb_panic+0x152/0x1d0 net/core/skbuff.c:122
Code: 0f b6 04 01 84 c0 74 04 3c 03 7e 20 8b 4b 70 41 56 45 89 e8 48 c7 c7 40 11 5c 8b 41 57 56 48 89 ee 52 4c 89 e2 e8 de 43 5e f9 <0f> 0b 4c 89 4c 24 10 48 89 54 24 08 48 89 34 24 e8 a9 66 c9 f9 4c
RSP: 0018:ffffc90000a1fbc0 EFLAGS: 00010286
RAX: 0000000000000084 RBX: ffff88802b3e6500 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8168dfbc RDI: 0000000000000005
RBP: ffffffff8b5c1f80 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000001 R11: 0000000000000000 R12: ffffffff8615b76f
R13: 0000000000000014 R14: ffffffff8b5c1100 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdf942b0150 CR3: 000000007a8e3000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
skb_over_panic net/core/skbuff.c:127 [inline]
skb_put+0x16f/0x1a0 net/core/skbuff.c:2261
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:764 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:808 [inline]
nsim_dev_trap_report_work+0x4df/0xc80 drivers/net/netdevsim/dev.c:853
process_one_work+0x9bf/0x1820 kernel/workqueue.c:2390
worker_thread+0x669/0x1090 kernel/workqueue.c:2537
kthread+0x2e8/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:skb_panic+0x152/0x1d0 net/core/skbuff.c:122
Code: 0f b6 04 01 84 c0 74 04 3c 03 7e 20 8b 4b 70 41 56 45 89 e8 48 c7 c7 40 11 5c 8b 41 57 56 48 89 ee 52 4c 89 e2 e8 de 43 5e f9 <0f> 0b 4c 89 4c 24 10 48 89 54 24 08 48 89 34 24 e8 a9 66 c9 f9 4c
RSP: 0018:ffffc90000a1fbc0 EFLAGS: 00010286
RAX: 0000000000000084 RBX: ffff88802b3e6500 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8168dfbc RDI: 0000000000000005
RBP: ffffffff8b5c1f80 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000080000001 R11: 0000000000000000 R12: ffffffff8615b76f
R13: 0000000000000014 R14: ffffffff8b5c1100 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdf942b0150 CR3: 000000007a8e3000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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 syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches

[Hillf Danton]

On Mon, 06 Feb 2023 01:23:40 -0800

> syzbot found the following issue on:
>
> HEAD commit: 4fafd96910ad Add linux-next specific files for 20230203
> git tree: linux-next

> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14911ba5480000

See if it is due to ref leak.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 4fafd96910ad

--- x/block/bio.c
+++ y/block/bio.c
@@ -1208,11 +1208,8 @@ static int bio_iov_add_page(struct bio *

if (!__bio_try_merge_page(bio, page, len, offset, &same_page)) {
__bio_add_page(bio, page, len, offset);
- return 0;
}

- if (same_page)
- bio_release_page(bio, page);
return 0;
}

@@ -1225,8 +1222,6 @@ static int bio_iov_add_zone_append_page(
if (bio_add_hw_page(q, bio, page, len, offset,
queue_max_zone_append_sectors(q), &same_page) != len)
return -EINVAL;
- if (same_page)
- bio_release_page(bio, page);
return 0;
}

--

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
kernel BUG in __tlb_remove_page_size

exit_mmap+0x205/0x7d0 mm/mmap.c:3047
__mmput+0x128/0x4c0 kernel/fork.c:1209
mmput+0x60/0x70 kernel/fork.c:1231
exit_mm kernel/exit.c:563 [inline]
do_exit+0x9d7/0x2b60 kernel/exit.c:856
do_group_exit+0xd4/0x2a0 kernel/exit.c:1019
__do_sys_exit_group kernel/exit.c:1030 [inline]
__se_sys_exit_group kernel/exit.c:1028 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1028
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
------------[ cut here ]------------
kernel BUG at mm/mmu_gather.c:139!

invalid opcode: 0000 [#1] PREEMPT SMP KASAN

CPU: 0 PID: 5610 Comm: dhcpcd-run-hook Not tainted 6.2.0-rc6-next-20230203-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023

RIP: 0010:__tlb_remove_page_size+0x24c/0x480 mm/mmu_gather.c:139
Code: 01 00 00 8b 6d 0c e9 e1 fe ff ff e8 ae 63 c1 ff 0f 0b e8 a7 63 c1 ff 4c 89 f7 48 c7 c6 c0 77 58 8a 48 83 e7 fc e8 64 0b fa ff <0f> 0b e8 8d 63 c1 ff 4c 8d 6b 24 48 b8 00 00 00 00 00 fc ff df 4c
RSP: 0018:ffffc9000556f700 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffc9000556f9d0 RCX: 0000000000000000
RDX: ffff88802c0a57c0 RSI: ffffffff81c3070c RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff8e751757
R10: fffffbfff1cea2ea R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000001 R14: ffffea00009b4f40 R15: ffffc9000556f9f8
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 000055b779edb950 CR3: 000000002c188000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>

tlb_remove_page_size include/asm-generic/tlb.h:466 [inline]
tlb_remove_page+0x12/0x30 include/asm-generic/tlb.h:481
paravirt_tlb_remove_table arch/x86/include/asm/paravirt.h:92 [inline]
___pte_free_tlb+0x123/0x1a0 arch/x86/mm/pgtable.c:57
__pte_free_tlb arch/x86/include/asm/pgalloc.h:61 [inline]
free_pte_range mm/memory.c:179 [inline]
free_pmd_range mm/memory.c:197 [inline]
free_pud_range mm/memory.c:231 [inline]
free_p4d_range mm/memory.c:265 [inline]
free_pgd_range+0x497/0xbf0 mm/memory.c:345
free_pgtables+0x2d6/0x420 mm/memory.c:386
exit_mmap+0x1f3/0x7d0 mm/mmap.c:3045
__mmput+0x128/0x4c0 kernel/fork.c:1209
mmput+0x60/0x70 kernel/fork.c:1231
exec_mmap fs/exec.c:1034 [inline]
begin_new_exec+0xf69/0x2e60 fs/exec.c:1293
load_elf_binary+0x801/0x4ff0 fs/binfmt_elf.c:1001
search_binary_handler fs/exec.c:1736 [inline]
exec_binprm fs/exec.c:1778 [inline]
bprm_execve fs/exec.c:1853 [inline]
bprm_execve+0x7fd/0x1b00 fs/exec.c:1809
do_execveat_common+0x72c/0x8e0 fs/exec.c:1961
do_execve fs/exec.c:2035 [inline]
__do_sys_execve fs/exec.c:2111 [inline]
__se_sys_execve fs/exec.c:2106 [inline]
__x64_sys_execve+0x93/0xc0 fs/exec.c:2106
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f634f470337
Code: Unable to access opcode bytes at 0x7f634f47030d.
RSP: 002b:00007ffd71eedd08 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 000055b779eecd88 RCX: 00007f634f470337
RDX: 000055b779eecde8 RSI: 000055b779eecd88 RDI: 000055b779eece70
RBP: 000055b779eece70 R08: 000055b779eece75 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 000055b779eecde8
R13: 00007f634f615ff4 R14: 000055b779eecde8 R15: 0000000000000000

</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---

RIP: 0010:__tlb_remove_page_size+0x24c/0x480 mm/mmu_gather.c:139
Code: 01 00 00 8b 6d 0c e9 e1 fe ff ff e8 ae 63 c1 ff 0f 0b e8 a7 63 c1 ff 4c 89 f7 48 c7 c6 c0 77 58 8a 48 83 e7 fc e8 64 0b fa ff <0f> 0b e8 8d 63 c1 ff 4c 8d 6b 24 48 b8 00 00 00 00 00 fc ff df 4c
RSP: 0018:ffffc9000556f700 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffc9000556f9d0 RCX: 0000000000000000
RDX: ffff88802c0a57c0 RSI: ffffffff81c3070c RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff8e751757
R10: fffffbfff1cea2ea R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000001 R14: ffffea00009b4f40 R15: ffffc9000556f9f8
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f634f47030d CR3: 000000002c188000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Tested on:

commit: 4fafd969 Add linux-next specific files for 20230203
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
console output: https://syzkaller.appspot.com/x/log.txt?x=1107ca0f480000

kernel config: https://syzkaller.appspot.com/x/.config?x=1d2fba7d42502ca4
dashboard link: https://syzkaller.appspot.com/bug?extid=c0998868487c1f7e05e5
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=13d29897480000

[Hillf Danton]

On Mon, 06 Feb 2023 01:23:40 -0800

> syzbot found the following issue on:
>
> HEAD commit: 4fafd96910ad Add linux-next specific files for 20230203
> git tree: linux-next

> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14911ba5480000

See if it is due to ref leak.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 4fafd96910ad

--- x/block/bio.c
+++ y/block/bio.c
@@ -1208,11 +1208,8 @@ static int bio_iov_add_page(struct bio *

if (!__bio_try_merge_page(bio, page, len, offset, &same_page)) {
__bio_add_page(bio, page, len, offset);
- return 0;
}

- if (same_page)
- bio_release_page(bio, page);
return 0;
}

@@ -1225,8 +1222,6 @@ static int bio_iov_add_zone_append_page(
if (bio_add_hw_page(q, bio, page, len, offset,
queue_max_zone_append_sectors(q), &same_page) != len)
return -EINVAL;
- if (same_page)
- bio_release_page(bio, page);
return 0;
}

--- x/mm/mmu_gather.c
+++ y/mm/mmu_gather.c
@@ -26,7 +26,11 @@ static bool tlb_next_batch(struct mmu_ga
batch = tlb->active;
if (batch->next) {
tlb->active = batch->next;
- return true;
+ batch = tlb->active;
+ if (batch->nr < batch->max)
+ return true;
+ else
+ return false;
}

if (tlb->batch_count == MAX_GATHER_BATCH_COUNT)
--

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
kernel BUG in __tlb_remove_page_size

pipe_buf_release include/linux/pipe_fs_i.h:183 [inline]
iov_iter_revert.part.0+0x402/0x730 lib/iov_iter.c:935
iov_iter_revert+0x4c/0x60 lib/iov_iter.c:919
__iomap_dio_rw+0x16cb/0x1d80 fs/iomap/direct-io.c:610
iomap_dio_rw+0x40/0xa0 fs/iomap/direct-io.c:682
ext4_dio_read_iter fs/ext4/file.c:94 [inline]
ext4_file_read_iter+0x4be/0x690 fs/ext4/file.c:145
call_read_iter include/linux/fs.h:1845 [inline]
generic_file_splice_read+0x182/0x4b0 fs/splice.c:309
do_splice_to+0x1b9/0x240 fs/splice.c:793
splice_direct_to_actor+0x2ab/0x8a0 fs/splice.c:865
do_splice_direct+0x1ab/0x280 fs/splice.c:974
do_sendfile+0xb19/0x12c0 fs/read_write.c:1255
__do_sys_sendfile64 fs/read_write.c:1323 [inline]
__se_sys_sendfile64 fs/read_write.c:1309 [inline]
__x64_sys_sendfile64+0x1d0/0x210 fs/read_write.c:1309

do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80

------------[ cut here ]------------
kernel BUG at mm/mmu_gather.c:143!

invalid opcode: 0000 [#1] PREEMPT SMP KASAN

CPU: 0 PID: 5736 Comm: dhcpcd-run-hook Not tainted 6.2.0-rc6-next-20230203-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023

RIP: 0010:__tlb_remove_page_size+0x25b/0x480 mm/mmu_gather.c:143
Code: 0f 82 d6 fe ff ff e9 4e ff ff ff e8 9f 63 c1 ff 0f 0b e8 98 63 c1 ff 4c 89 f7 48 c7 c6 c0 77 58 8a 48 83 e7 fc e8 55 0b fa ff <0f> 0b e8 8e 66 10 00 e9 94 fe ff ff e8 84 66 10 00 e9 2b fe ff ff
RSP: 0018:ffffc90005207700 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffc900052079d0 RCX: 0000000000000000
RDX: ffff888020ac3a80 RSI: ffffffff81c3071b RDI: 0000000000000000

RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff8e751757

R10: fffffbfff1cea2ea R11: 0000000000000001 R12: 0000000000000001
R13: 0000000000000000 R14: ffffea0000ab5f80 R15: ffffc900052079f8

FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007fb7e7115829 CR3: 0000000070a22000 CR4: 00000000003506f0

RIP: 0033:0x7f9716b02337
Code: Unable to access opcode bytes at 0x7f9716b0230d.
RSP: 002b:00007ffd26cedb58 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 0000558ec09bde40 RCX: 00007f9716b02337
RDX: 0000558ec09bde68 RSI: 0000558ec09bde40 RDI: 0000558ec09bdef8
RBP: 0000558ec09bdef8 R08: 0000558ec09bdefd R09: 00007f9716cf4000
R10: 00007f9716998800 R11: 0000000000000246 R12: 0000558ec09bde68
R13: 00007f9716ca7ff4 R14: 0000558ec09bde68 R15: 0000000000000000

</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---

RIP: 0010:__tlb_remove_page_size+0x25b/0x480 mm/mmu_gather.c:143
Code: 0f 82 d6 fe ff ff e9 4e ff ff ff e8 9f 63 c1 ff 0f 0b e8 98 63 c1 ff 4c 89 f7 48 c7 c6 c0 77 58 8a 48 83 e7 fc e8 55 0b fa ff <0f> 0b e8 8e 66 10 00 e9 94 fe ff ff e8 84 66 10 00 e9 2b fe ff ff
RSP: 0018:ffffc90005207700 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffc900052079d0 RCX: 0000000000000000
RDX: ffff888020ac3a80 RSI: ffffffff81c3071b RDI: 0000000000000000

RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff8e751757

R10: fffffbfff1cea2ea R11: 0000000000000001 R12: 0000000000000001
R13: 0000000000000000 R14: ffffea0000ab5f80 R15: ffffc900052079f8
FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007fb7e7115829 CR3: 0000000070a22000 CR4: 00000000003506e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


Tested on:

commit: 4fafd969 Add linux-next specific files for 20230203
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

console output: https://syzkaller.appspot.com/x/log.txt?x=14a4295d480000

kernel config: https://syzkaller.appspot.com/x/.config?x=1d2fba7d42502ca4
dashboard link: https://syzkaller.appspot.com/bug?extid=c0998868487c1f7e05e5
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=11e01439480000

[Hillf Danton]

On Mon, 06 Feb 2023 01:23:40 -0800

> syzbot found the following issue on:
>
> HEAD commit: 4fafd96910ad Add linux-next specific files for 20230203
> git tree: linux-next

> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14911ba5480000

See if it is due to ref leak.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 4fafd96910ad

--- x/fs/splice.c
+++ y/fs/splice.c
@@ -91,7 +91,6 @@ out_unlock:
static void page_cache_pipe_buf_release(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
- put_page(buf->page);
buf->flags &= ~PIPE_BUF_FLAG_LRU;
}

--

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
kernel BUG in __tlb_remove_page_size

page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1453 [inline]
free_pcp_prepare+0x4d0/0x910 mm/page_alloc.c:1503
free_unref_page_prepare mm/page_alloc.c:3390 [inline]
free_unref_page+0x1d/0x490 mm/page_alloc.c:3485
free_reserved_page include/linux/mm.h:2796 [inline]
free_reserved_area+0x15d/0x200 mm/page_alloc.c:8538
free_init_pages+0x94/0xc0 arch/x86/mm/init.c:915
kernel_init+0x32/0x2c0 init/main.c:1531
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
------------[ cut here ]------------
kernel BUG at mm/mmu_gather.c:139!

invalid opcode: 0000 [#1] PREEMPT SMP KASAN

CPU: 1 PID: 5672 Comm: dhcpcd-run-hook Not tainted 6.2.0-rc6-next-20230203-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023

RIP: 0010:__tlb_remove_page_size+0x24c/0x480 mm/mmu_gather.c:139
Code: 01 00 00 8b 6d 0c e9 e1 fe ff ff e8 ae 63 c1 ff 0f 0b e8 a7 63 c1 ff 4c 89 f7 48 c7 c6 c0 77 58 8a 48 83 e7 fc e8 64 0b fa ff <0f> 0b e8 8d 63 c1 ff 4c 8d 6b 24 48 b8 00 00 00 00 00 fc ff df 4c

RSP: 0018:ffffc90005a6f5d0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffc90005a6f9d0 RCX: 0000000000000000
RDX: ffff88801ed80000 RSI: ffffffff81c3070c RDI: 0000000000000000

RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff8e751757

R10: fffffbfff1cea2ea R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000001 R14: ffffea00003fde40 R15: ffffc90005a6f9f8

FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f6eb4c40900 CR3: 0000000071157000 CR4: 00000000003506e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Call Trace:
<TASK>
__tlb_remove_page include/asm-generic/tlb.h:472 [inline]
zap_pte_range mm/memory.c:1416 [inline]
zap_pmd_range mm/memory.c:1536 [inline]
zap_pud_range mm/memory.c:1565 [inline]
zap_p4d_range mm/memory.c:1586 [inline]
unmap_page_range+0x1226/0x3ce0 mm/memory.c:1607
unmap_single_vma+0x194/0x2a0 mm/memory.c:1653
unmap_vmas+0x234/0x380 mm/memory.c:1692
exit_mmap+0x190/0x7d0 mm/mmap.c:3036

__mmput+0x128/0x4c0 kernel/fork.c:1209
mmput+0x60/0x70 kernel/fork.c:1231
exec_mmap fs/exec.c:1034 [inline]
begin_new_exec+0xf69/0x2e60 fs/exec.c:1293
load_elf_binary+0x801/0x4ff0 fs/binfmt_elf.c:1001
search_binary_handler fs/exec.c:1736 [inline]
exec_binprm fs/exec.c:1778 [inline]
bprm_execve fs/exec.c:1853 [inline]
bprm_execve+0x7fd/0x1b00 fs/exec.c:1809
do_execveat_common+0x72c/0x8e0 fs/exec.c:1961
do_execve fs/exec.c:2035 [inline]
__do_sys_execve fs/exec.c:2111 [inline]
__se_sys_execve fs/exec.c:2106 [inline]
__x64_sys_execve+0x93/0xc0 fs/exec.c:2106
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

RIP: 0033:0x7f6eb4bb0337
Code: Unable to access opcode bytes at 0x7f6eb4bb030d.
RSP: 002b:00007ffe1aff9aa8 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 000055f08f0f5e40 RCX: 00007f6eb4bb0337
RDX: 000055f08f0f5e68 RSI: 000055f08f0f5e40 RDI: 000055f08f0f5ef8
RBP: 000055f08f0f5ef8 R08: 000055f08f0f5efd R09: 00007f6eb4da2000
R10: 00007f6eb4a46800 R11: 0000000000000246 R12: 000055f08f0f5e68
R13: 00007f6eb4d55ff4 R14: 000055f08f0f5e68 R15: 0000000000000000

</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---

RIP: 0010:__tlb_remove_page_size+0x24c/0x480 mm/mmu_gather.c:139
Code: 01 00 00 8b 6d 0c e9 e1 fe ff ff e8 ae 63 c1 ff 0f 0b e8 a7 63 c1 ff 4c 89 f7 48 c7 c6 c0 77 58 8a 48 83 e7 fc e8 64 0b fa ff <0f> 0b e8 8d 63 c1 ff 4c 8d 6b 24 48 b8 00 00 00 00 00 fc ff df 4c

RSP: 0018:ffffc90005a6f5d0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffc90005a6f9d0 RCX: 0000000000000000
RDX: ffff88801ed80000 RSI: ffffffff81c3070c RDI: 0000000000000000

RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff8e751757

R10: fffffbfff1cea2ea R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000001 R14: ffffea00003fde40 R15: ffffc90005a6f9f8

FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f6eb4bb030d CR3: 0000000071157000 CR4: 00000000003506e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


Tested on:

commit: 4fafd969 Add linux-next specific files for 20230203
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

console output: https://syzkaller.appspot.com/x/log.txt?x=13b20813480000

kernel config: https://syzkaller.appspot.com/x/.config?x=1d2fba7d42502ca4
dashboard link: https://syzkaller.appspot.com/bug?extid=c0998868487c1f7e05e5
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=163a5987480000

[Hillf Danton]

On Mon, 06 Feb 2023 01:23:40 -0800

> syzbot found the following issue on:
>
> HEAD commit: 4fafd96910ad Add linux-next specific files for 20230203
> git tree: linux-next

> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14911ba5480000

See if it is due to ref leak.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 4fafd96910ad

--- x/mm/mmu_gather.c
+++ y/mm/mmu_gather.c
@@ -26,7 +26,11 @@ static bool tlb_next_batch(struct mmu_ga
batch = tlb->active;
if (batch->next) {
tlb->active = batch->next;
- return true;
+ batch = tlb->active;
+ if (batch->nr < batch->max)
+ return true;
+ else
+ return false;
}

if (tlb->batch_count == MAX_GATHER_BATCH_COUNT)

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:

BUG: Bad rss-counter state

BUG: Bad rss-counter state mm:ffff88807dca8900 type:MM_ANONPAGES val:1
BUG: non-zero pgtables_bytes on freeing mm: 8192

Tested on:

commit: 4fafd969 Add linux-next specific files for 20230203
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

console output: https://syzkaller.appspot.com/x/log.txt?x=1242a20f480000

kernel config: https://syzkaller.appspot.com/x/.config?x=1d2fba7d42502ca4
dashboard link: https://syzkaller.appspot.com/bug?extid=c0998868487c1f7e05e5
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=1754166b480000

[Hillf Danton]

On Mon, 06 Feb 2023 01:23:40 -0800

> syzbot found the following issue on:
>
> HEAD commit: 4fafd96910ad Add linux-next specific files for 20230203
> git tree: linux-next

> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14911ba5480000

See if it is due to ref leak.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 4fafd96910ad

--- x/mm/mmu_gather.c
+++ y/mm/mmu_gather.c
@@ -26,7 +26,11 @@ static bool tlb_next_batch(struct mmu_ga
batch = tlb->active;
if (batch->next) {
tlb->active = batch->next;
- return true;
+ batch = tlb->active;
+ if (batch->nr < batch->max)
+ return true;
+ else
+ return false;
}

if (tlb->batch_count == MAX_GATHER_BATCH_COUNT)
--- x/fs/splice.c
+++ y/fs/splice.c
@@ -91,7 +91,6 @@ out_unlock:
static void page_cache_pipe_buf_release(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
- put_page(buf->page);
buf->flags &= ~PIPE_BUF_FLAG_LRU;
}

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
BUG: Bad rss-counter state

BUG: Bad rss-counter state mm:ffff88807ac59200 type:MM_ANONPAGES val:1
BUG: non-zero pgtables_bytes on freeing mm: 12288

Tested on:

commit: 4fafd969 Add linux-next specific files for 20230203
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

console output: https://syzkaller.appspot.com/x/log.txt?x=130232a3480000

kernel config: https://syzkaller.appspot.com/x/.config?x=1d2fba7d42502ca4
dashboard link: https://syzkaller.appspot.com/bug?extid=c0998868487c1f7e05e5
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=10602ee3480000

[Hillf Danton]

On Mon, 06 Feb 2023 01:23:40 -0800

> syzbot found the following issue on:
>
> HEAD commit: 4fafd96910ad Add linux-next specific files for 20230203
> git tree: linux-next

> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14911ba5480000

See if it is due to ref leak.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 4fafd96910ad

--- x/mm/mmu_gather.c
+++ y/mm/mmu_gather.c
@@ -26,7 +26,11 @@ static bool tlb_next_batch(struct mmu_ga
batch = tlb->active;
if (batch->next) {
tlb->active = batch->next;
- return true;
+ batch = tlb->active;
+ if (batch->nr < batch->max)
+ return true;
+ else
+ return false;
}

if (tlb->batch_count == MAX_GATHER_BATCH_COUNT)

--- x/block/bio.c
+++ y/block/bio.c
@@ -1342,8 +1342,7 @@ int bio_iov_iter_get_pages(struct bio *b
return 0;
}

- if (iov_iter_extract_will_pin(iter))
- bio_set_flag(bio, BIO_PAGE_PINNED);
+ bio_set_flag(bio, BIO_PAGE_REFFED);
do {
ret = __bio_iov_iter_get_pages(bio, iter);
} while (!ret && iov_iter_count(iter) && !bio_full(bio, 0));
--

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:

kernel BUG in __bio_release_pages

do_splice_direct+0x1ab/0x280 fs/splice.c:974
do_sendfile+0xb19/0x12c0 fs/read_write.c:1255
__do_sys_sendfile64 fs/read_write.c:1323 [inline]
__se_sys_sendfile64 fs/read_write.c:1309 [inline]
__x64_sys_sendfile64+0x1d0/0x210 fs/read_write.c:1309

do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80

------------[ cut here ]------------
kernel BUG at include/linux/mm.h:868!

invalid opcode: 0000 [#1] PREEMPT SMP KASAN

CPU: 1 PID: 1760 Comm: kworker/1:2 Not tainted 6.2.0-rc6-next-20230203-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023

Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:put_page_testzero include/linux/mm.h:868 [inline]
RIP: 0010:folio_put_testzero include/linux/mm.h:874 [inline]
RIP: 0010:folio_put include/linux/mm.h:1303 [inline]
RIP: 0010:put_page include/linux/mm.h:1373 [inline]
RIP: 0010:bio_release_page block/blk.h:437 [inline]
RIP: 0010:__bio_release_pages+0x546/0x610 block/bio.c:1179
Code: 04 24 48 83 e8 01 48 89 04 24 48 89 44 24 30 e9 0c fe ff ff e8 4b 6f 8b fd 48 8b 7c 24 30 48 c7 c6 40 72 a4 8a e8 0a 17 c4 fd <0f> 0b 48 8b 7c 24 08 e8 1e 72 da fd e9 f2 fa ff ff 48 8b 7c 24 08
RSP: 0018:ffffc900001e0ca0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffea0001f32000 RCX: 0000000000000100
RDX: ffff888021ff9d40 RSI: ffffffff83f8fb66 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8e751757
R10: fffffbfff1cea2ea R11: 0000000000000001 R12: 0000000000000000
R13: ffff88802af8ba00 R14: ffffea0001f32034 R15: 0000000000000002

FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 000055ba0a633950 CR3: 0000000075f9d000 CR4: 00000000003506e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:

<IRQ>
bio_release_pages include/linux/bio.h:493 [inline]
iomap_dio_bio_end_io+0x373/0x5e0 fs/iomap/direct-io.c:185
bio_endio+0x62d/0x7f0 block/bio.c:1615
req_bio_endio block/blk-mq.c:794 [inline]
blk_update_request+0x3a5/0x1430 block/blk-mq.c:926
scsi_end_request+0x7a/0xa20 drivers/scsi/scsi_lib.c:537
scsi_io_completion+0x177/0x1f80 drivers/scsi/scsi_lib.c:975
scsi_complete+0x126/0x3b0 drivers/scsi/scsi_lib.c:1439
blk_complete_reqs+0xad/0xe0 block/blk-mq.c:1131
__do_softirq+0x2e3/0xae3 kernel/softirq.c:571
do_softirq.part.0+0xde/0x130 kernel/softirq.c:472
</IRQ>
<TASK>
do_softirq kernel/softirq.c:464 [inline]
__local_bh_enable_ip+0x106/0x130 kernel/softirq.c:396
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:843 [inline]
ip6_finish_output2+0x5be/0x1590 net/ipv6/ip6_output.c:135
__ip6_finish_output net/ipv6/ip6_output.c:195 [inline]
ip6_finish_output+0x694/0x1170 net/ipv6/ip6_output.c:206
NF_HOOK_COND include/linux/netfilter.h:291 [inline]
ip6_output+0x1f1/0x540 net/ipv6/ip6_output.c:227
dst_output include/net/dst.h:444 [inline]
NF_HOOK include/linux/netfilter.h:302 [inline]
ndisc_send_skb+0xa63/0x1850 net/ipv6/ndisc.c:508
ndisc_send_ns+0xaa/0x130 net/ipv6/ndisc.c:666
addrconf_dad_work+0xbf4/0x1390 net/ipv6/addrconf.c:4176

process_one_work+0x9bf/0x1820 kernel/workqueue.c:2390
worker_thread+0x669/0x1090 kernel/workqueue.c:2537
kthread+0x2e8/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---

RIP: 0010:put_page_testzero include/linux/mm.h:868 [inline]
RIP: 0010:folio_put_testzero include/linux/mm.h:874 [inline]
RIP: 0010:folio_put include/linux/mm.h:1303 [inline]
RIP: 0010:put_page include/linux/mm.h:1373 [inline]
RIP: 0010:bio_release_page block/blk.h:437 [inline]
RIP: 0010:__bio_release_pages+0x546/0x610 block/bio.c:1179
Code: 04 24 48 83 e8 01 48 89 04 24 48 89 44 24 30 e9 0c fe ff ff e8 4b 6f 8b fd 48 8b 7c 24 30 48 c7 c6 40 72 a4 8a e8 0a 17 c4 fd <0f> 0b 48 8b 7c 24 08 e8 1e 72 da fd e9 f2 fa ff ff 48 8b 7c 24 08
RSP: 0018:ffffc900001e0ca0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffea0001f32000 RCX: 0000000000000100
RDX: ffff888021ff9d40 RSI: ffffffff83f8fb66 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8e751757
R10: fffffbfff1cea2ea R11: 0000000000000001 R12: 0000000000000000
R13: ffff88802af8ba00 R14: ffffea0001f32034 R15: 0000000000000002

FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 000055ba0a633950 CR3: 0000000075f9d000 CR4: 00000000003506e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


Tested on:

commit: 4fafd969 Add linux-next specific files for 20230203
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

console output: https://syzkaller.appspot.com/x/log.txt?x=1218216d480000

kernel config: https://syzkaller.appspot.com/x/.config?x=1d2fba7d42502ca4
dashboard link: https://syzkaller.appspot.com/bug?extid=c0998868487c1f7e05e5
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=153c325b480000

[Hillf Danton]

On Mon, 06 Feb 2023 01:23:40 -0800

> syzbot found the following issue on:
>
> HEAD commit: 4fafd96910ad Add linux-next specific files for 20230203
> git tree: linux-next

> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14911ba5480000

See if it is due to ref leak.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 4fafd96910ad

--- x/mm/mmu_gather.c
+++ y/mm/mmu_gather.c
@@ -26,7 +26,11 @@ static bool tlb_next_batch(struct mmu_ga
batch = tlb->active;
if (batch->next) {
tlb->active = batch->next;
- return true;
+ batch = tlb->active;
+ if (batch->nr < batch->max)
+ return true;
+ else
+ return false;
}

if (tlb->batch_count == MAX_GATHER_BATCH_COUNT)
--- x/block/bio.c
+++ y/block/bio.c

@@ -1253,6 +1253,7 @@ static int __bio_iov_iter_get_pages(stru
unsigned len, i = 0;
size_t offset, trim;
int ret = 0;
+ int setref = 0;

/*
* Move page array up in the allocated memory for the bio vecs as far as
@@ -1302,13 +1303,16 @@ static int __bio_iov_iter_get_pages(stru
bio_iov_add_page(bio, page, len, offset);

offset = 0;
+ get_page(page);
}
+ setref = i;

- iov_iter_revert(iter, left);
out:
while (i < nr_pages)
bio_release_page(bio, pages[i++]);

+ if (setref)
+ bio_set_flag(bio, BIO_PAGE_REFFED);
return ret;
}

@@ -1342,8 +1346,6 @@ int bio_iov_iter_get_pages(struct bio *b

return 0;
}

- if (iov_iter_extract_will_pin(iter))
- bio_set_flag(bio, BIO_PAGE_PINNED);

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+c09988...@syzkaller.appspotmail.com

Tested on:

commit: 4fafd969 Add linux-next specific files for 20230203
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

console output: https://syzkaller.appspot.com/x/log.txt?x=1753218d480000

kernel config: https://syzkaller.appspot.com/x/.config?x=1d2fba7d42502ca4
dashboard link: https://syzkaller.appspot.com/bug?extid=c0998868487c1f7e05e5
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

patch: https://syzkaller.appspot.com/x/patch.diff?x=15a33033480000

Note: testing is done by a robot and is best-effort only.

[David Howells]

#syz test: https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/ iov-fixes

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+c09988...@syzkaller.appspotmail.com

Tested on:

commit: fab9eebf iov_iter: Kill ITER_PIPE
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/ iov-fixes
console output: https://syzkaller.appspot.com/x/log.txt?x=1529647b480000
kernel config: https://syzkaller.appspot.com/x/.config?x=facc234423e66dc6

dashboard link: https://syzkaller.appspot.com/bug?extid=c0998868487c1f7e05e5
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

Note: no patches were applied.

[David Howells]

#syz dup: [syzbot] general protection fault in skb_dequeue (3)