All of lore.kernel.org
 help / color / mirror / Atom feed
From: Eric Dumazet <edumazet@google.com>
To: Jan Kara <jack@suse.com>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
	Eric Dumazet <edumazet@google.com>,
	Eric Dumazet <eric.dumazet@gmail.com>
Subject: [PATCH] quota: clear padding in v2r1_mem2diskdqb()
Date: Thu, 24 Sep 2020 11:36:19 -0700	[thread overview]
Message-ID: <20200924183619.4176790-1-edumazet@google.com> (raw)

Freshly allocated memory contains garbage, better make sure
to init all struct v2r1_disk_dqblk fields to avoid KMSAN report:

BUG: KMSAN: uninit-value in qtree_entry_unused+0x137/0x1b0 fs/quota/quota_tree.c:218
CPU: 0 PID: 23373 Comm: syz-executor.1 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:219
 qtree_entry_unused+0x137/0x1b0 fs/quota/quota_tree.c:218
 v2r1_mem2diskdqb+0x43d/0x710 fs/quota/quota_v2.c:285
 qtree_write_dquot+0x226/0x870 fs/quota/quota_tree.c:394
 v2_write_dquot+0x1ad/0x280 fs/quota/quota_v2.c:333
 dquot_commit+0x4af/0x600 fs/quota/dquot.c:482
 ext4_write_dquot fs/ext4/super.c:5934 [inline]
 ext4_mark_dquot_dirty+0x4d8/0x6a0 fs/ext4/super.c:5985
 mark_dquot_dirty fs/quota/dquot.c:347 [inline]
 mark_all_dquot_dirty fs/quota/dquot.c:385 [inline]
 dquot_alloc_inode+0xc05/0x12b0 fs/quota/dquot.c:1755
 __ext4_new_inode+0x8204/0x9d70 fs/ext4/ialloc.c:1155
 ext4_tmpfile+0x41a/0x850 fs/ext4/namei.c:2686
 vfs_tmpfile+0x2a2/0x570 fs/namei.c:3283
 do_tmpfile fs/namei.c:3316 [inline]
 path_openat+0x4035/0x6a90 fs/namei.c:3359
 do_filp_open+0x2b8/0x710 fs/namei.c:3395
 do_sys_openat2+0xa88/0x1140 fs/open.c:1168
 do_sys_open fs/open.c:1184 [inline]
 __do_compat_sys_openat fs/open.c:1242 [inline]
 __se_compat_sys_openat+0x2a4/0x310 fs/open.c:1240
 __ia32_compat_sys_openat+0x56/0x70 fs/open.c:1240
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7ff4549
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f55cd0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 0000000020000000
RDX: 0000000000410481 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:143 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:126
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2907 [inline]
 slab_alloc mm/slub.c:2916 [inline]
 __kmalloc+0x2bb/0x4b0 mm/slub.c:3982
 kmalloc include/linux/slab.h:559 [inline]
 getdqbuf+0x56/0x150 fs/quota/quota_tree.c:52
 qtree_write_dquot+0xf2/0x870 fs/quota/quota_tree.c:378
 v2_write_dquot+0x1ad/0x280 fs/quota/quota_v2.c:333
 dquot_commit+0x4af/0x600 fs/quota/dquot.c:482
 ext4_write_dquot fs/ext4/super.c:5934 [inline]
 ext4_mark_dquot_dirty+0x4d8/0x6a0 fs/ext4/super.c:5985
 mark_dquot_dirty fs/quota/dquot.c:347 [inline]
 mark_all_dquot_dirty fs/quota/dquot.c:385 [inline]
 dquot_alloc_inode+0xc05/0x12b0 fs/quota/dquot.c:1755
 __ext4_new_inode+0x8204/0x9d70 fs/ext4/ialloc.c:1155
 ext4_tmpfile+0x41a/0x850 fs/ext4/namei.c:2686
 vfs_tmpfile+0x2a2/0x570 fs/namei.c:3283
 do_tmpfile fs/namei.c:3316 [inline]
 path_openat+0x4035/0x6a90 fs/namei.c:3359
 do_filp_open+0x2b8/0x710 fs/namei.c:3395
 do_sys_openat2+0xa88/0x1140 fs/open.c:1168
 do_sys_open fs/open.c:1184 [inline]
 __do_compat_sys_openat fs/open.c:1242 [inline]
 __se_compat_sys_openat+0x2a4/0x310 fs/open.c:1240
 __ia32_compat_sys_openat+0x56/0x70 fs/open.c:1240
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Fixes: 498c60153ebb ("quota: Implement quota format with 64-bit space and inode limits")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jan Kara <jack@suse.com>
---
 fs/quota/quota_v2.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/quota/quota_v2.c b/fs/quota/quota_v2.c
index 58fc2a7c7fd19f0be265e8189e476782571cbcfe..e69a2bfdd81c050c1ff2653528f803bd402fb399 100644
--- a/fs/quota/quota_v2.c
+++ b/fs/quota/quota_v2.c
@@ -282,6 +282,7 @@ static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot)
 	d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
 	d->dqb_btime = cpu_to_le64(m->dqb_btime);
 	d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
+	d->dqb_pad = 0;
 	if (qtree_entry_unused(info, dp))
 		d->dqb_itime = cpu_to_le64(1);
 }
-- 
2.28.0.681.g6f77f65b4e-goog


             reply	other threads:[~2020-09-24 18:36 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-24 18:36 Eric Dumazet [this message]
2020-09-25  9:16 ` [PATCH] quota: clear padding in v2r1_mem2diskdqb() Jan Kara

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200924183619.4176790-1-edumazet@google.com \
    --to=edumazet@google.com \
    --cc=eric.dumazet@gmail.com \
    --cc=jack@suse.com \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.