MIME-Version: 1.0
Date:   Fri, 07 Jan 2022 07:40:22 -0800
Message-ID: <0000000000000f2f3605d4ffce9e@google.com>
Subject: [syzbot] KMSAN: uninit-value in ext4_inode_journal_mode (2)
From:   syzbot <syzbot+11542230634289d7f1f6@syzkaller.appspotmail.com>
To:     adilger.kernel@dilger.ca, glider@google.com,
        linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org,
        syzkaller-bugs@googlegroups.com, tytso@mit.edu
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Hello,

syzbot found the following issue on:

HEAD commit:    81c325bbf94e kmsan: hooks: do not check memory in kmsan_in..
git tree:       https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=11473f2db00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2d8b9a11641dc9aa
dashboard link: https://syzkaller.appspot.com/bug?extid=11542230634289d7f1f6
compiler:       clang version 14.0.0 (/usr/local/google/src/llvm-git-monorepo 2b554920f11c8b763cd9ed9003f4e19b919b8e1f), GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+11542230634289d7f1f6@syzkaller.appspotmail.com

syz-executor.0 (pid 3634) is setting deprecated v1 encryption policy; recommend upgrading to v2.
=====================================================
BUG: KMSAN: uninit-value in ext4_inode_journal_mode+0x29f/0x510 fs/ext4/ext4_jbd2.c:16
 ext4_inode_journal_mode+0x29f/0x510 fs/ext4/ext4_jbd2.c:16
 ext4_should_journal_data fs/ext4/ext4_jbd2.h:465 [inline]
 ext4_evict_inode+0x1b5/0x2d10 fs/ext4/inode.c:202
 evict+0x4f4/0xdd0 fs/inode.c:590
 iput_final fs/inode.c:1670 [inline]
 iput+0xc53/0x1100 fs/inode.c:1696
 __ext4_new_inode+0xf32/0x8440 fs/ext4/ialloc.c:1362
 ext4_create+0x455/0x940 fs/ext4/namei.c:2746
 lookup_open fs/namei.c:3280 [inline]
 open_last_lookups fs/namei.c:3350 [inline]
 path_openat+0x2e88/0x5ea0 fs/namei.c:3556
 do_filp_open+0x306/0x760 fs/namei.c:3586
 do_sys_openat2+0x263/0x8f0 fs/open.c:1212
 do_sys_open fs/open.c:1228 [inline]
 __do_sys_creat fs/open.c:1304 [inline]
 __se_sys_creat fs/open.c:1298 [inline]
 __ia32_sys_creat+0x122/0x1a0 fs/open.c:1298
 do_syscall_32_irqs_on arch/x86/entry/common.c:114 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:180
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:205
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:248
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was created at:
 __alloc_pages+0xbbf/0x1090 mm/page_alloc.c:5409
 alloc_pages+0x8a5/0xb80
 alloc_slab_page mm/slub.c:1810 [inline]
 allocate_slab+0x287/0x1c10 mm/slub.c:1947
 new_slab mm/slub.c:2010 [inline]
 ___slab_alloc+0xb85/0x1e30 mm/slub.c:3039
 __slab_alloc mm/slub.c:3126 [inline]
 slab_alloc_node mm/slub.c:3217 [inline]
 slab_alloc mm/slub.c:3259 [inline]
 kmem_cache_alloc+0xbb3/0x11c0 mm/slub.c:3264
 ext4_alloc_inode+0x5e/0x870 fs/ext4/super.c:1295
 alloc_inode fs/inode.c:235 [inline]
 new_inode_pseudo+0xa6/0x5a0 fs/inode.c:944
 new_inode+0x5a/0x3c0 fs/inode.c:973
 __ext4_new_inode+0x3cb/0x8440 fs/ext4/ialloc.c:960
 ext4_mkdir+0x623/0x1870 fs/ext4/namei.c:2929
 vfs_mkdir+0x8ca/0xba0 fs/namei.c:3883
 do_mkdirat+0x3f5/0x8e0 fs/namei.c:3909
 __do_sys_mkdirat fs/namei.c:3924 [inline]
 __se_sys_mkdirat fs/namei.c:3922 [inline]
 __x64_sys_mkdirat+0x11a/0x160 fs/namei.c:3922
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

CPU: 0 PID: 3634 Comm: syz-executor.0 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
=====================================================


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