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Date:   Sun, 17 Sep 2023 21:41:08 -0700
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Subject: [syzbot] [fs?] [mm?] WARNING in page_copy_sane
From:   syzbot <syzbot+c225dea486da4d5592bd@syzkaller.appspotmail.com>
To:     akpm@linux-foundation.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        llvm@lists.linux.dev, mike.kravetz@oracle.com,
        muchun.song@linux.dev, nathan@kernel.org, ndesaulniers@google.com,
        sidhartha.kumar@oracle.com, syzkaller-bugs@googlegroups.com,
        trix@redhat.com, willy@infradead.org
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Hello,

syzbot found the following issue on:

HEAD commit:    98897dc735cf Add linux-next specific files for 20230914
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1548728c680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=1502c503717ada5c
dashboard link: https://syzkaller.appspot.com/bug?extid=c225dea486da4d5592bd
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=171fffd8680000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17bbbf1c680000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/00e4c0af5a8a/disk-98897dc7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7b54a00eee56/vmlinux-98897dc7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/100094353b8e/bzImage-98897dc7.xz

The issue was bisected to:

commit 591a2520fbfd6565d9a5c732afa53f62228798e6
Author: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Date:   Mon Sep 11 21:53:19 2023 +0000

    mm/filemap: remove hugetlb special casing in filemap.c

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=15e15464680000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=17e15464680000
console output: https://syzkaller.appspot.com/x/log.txt?x=13e15464680000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c225dea486da4d5592bd@syzkaller.appspotmail.com
Fixes: 591a2520fbfd ("mm/filemap: remove hugetlb special casing in filemap.c")

------------[ cut here ]------------
WARNING: CPU: 1 PID: 5040 at lib/iov_iter.c:463 page_copy_sane+0xc2/0x2c0 lib/iov_iter.c:463
Modules linked in:
CPU: 1 PID: 5040 Comm: syz-executor204 Not tainted 6.6.0-rc1-next-20230914-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
RIP: 0010:page_copy_sane+0xc2/0x2c0 lib/iov_iter.c:463
Code: e8 73 db 63 fd 66 90 e8 6c db 63 fd e8 67 db 63 fd 4c 89 ee 48 89 ef e8 6c d6 63 fd 49 39 ed 0f 83 eb 00 00 00 e8 4e db 63 fd <0f> 0b 31 db e8 45 db 63 fd 89 d8 5b 5d 41 5c 41 5d 41 5e 41 5f c3
RSP: 0018:ffffc90003eefa58 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88807a01d940 RSI: ffffffff84241482 RDI: 0000000000000006
RBP: 0000000000200000 R08: 0000000000000006 R09: 0000000000201000
R10: 0000000000200000 R11: 0000000000000000 R12: 0000000000000009
R13: 0000000000201000 R14: 0000000000000001 R15: ffffea0001fe0000
FS:  0000555556937380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200001c0 CR3: 000000002911d000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 copy_page_to_iter+0x35/0x180 lib/iov_iter.c:472
 hugetlbfs_read_iter+0x3d7/0xa60 fs/hugetlbfs/inode.c:385
 call_read_iter include/linux/fs.h:1980 [inline]
 do_iter_readv_writev+0x2f2/0x3c0 fs/read_write.c:733
 do_iter_read+0x315/0x870 fs/read_write.c:795
 vfs_readv+0x12d/0x1a0 fs/read_write.c:915
 do_preadv fs/read_write.c:1007 [inline]
 __do_sys_preadv fs/read_write.c:1057 [inline]
 __se_sys_preadv fs/read_write.c:1052 [inline]
 __x64_sys_preadv+0x228/0x300 fs/read_write.c:1052
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f85cc7932e9
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffda50bbbd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00007ffda50bbdb8 RCX: 00007f85cc7932e9
RDX: 0000000000000002 RSI: 0000000020000180 RDI: 0000000000000003
RBP: 00007f85cc806610 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffda50bbda8 R14: 0000000000000001 R15: 0000000000000001
 </TASK>


---
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