public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: "Theodore Ts'o" <tytso@mit.edu>
To: Ye Bin <yebin@huaweicloud.com>
Cc: adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org,
	linux-kernel@vger.kernel.org, jack@suse.cz,
	Ye Bin <yebin10@huawei.com>,
	syzbot+4d99a966fd74bdeeec36@syzkaller.appspotmail.com
Subject: Re: [PATCH v2] ext4: fix WARNING in ext4_expand_extra_isize_ea
Date: Thu, 1 Dec 2022 11:00:58 -0500	[thread overview]
Message-ID: <Y4jPuoJsW5+t9UUn@mit.edu> (raw)
In-Reply-To: <20221201145923.73028-1-yebin@huaweicloud.com>

On Thu, Dec 01, 2022 at 10:59:23PM +0800, Ye Bin wrote:
> 
> Reason is allocate 16M memory by kmalloc, but MAX_ORDER is 11, kmalloc
> can allocate maxium size memory is 4M.
> XATTR_SIZE_MAX is currently 64k, but EXT4_XATTR_SIZE_MAX is '(1 << 24)',
> so 'ext4_xattr_check_entries()' regards this length as legal. Then trigger
> warning in 'ext4_xattr_move_to_block()'.
> To solve above issue, according to Jan Kara's suggestion use kvmalloc()
> to allocate memory in ext4_xattr_move_to_block().

See my comment to the v1 version of the patch.  I suspect the real
problem is that the e_value_size is completely bogus, and we should
have checked it much earlier in the stack call trace, via a call to
xattr_check_inode().

Cheers,

					- Ted

  parent reply	other threads:[~2022-12-01 16:01 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-01 14:59 [PATCH v2] ext4: fix WARNING in ext4_expand_extra_isize_ea Ye Bin
2022-12-01 15:33 ` Jan Kara
2022-12-01 16:00 ` Theodore Ts'o [this message]
2022-12-01 16:12   ` yebin (H)

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=Y4jPuoJsW5+t9UUn@mit.edu \
    --to=tytso@mit.edu \
    --cc=adilger.kernel@dilger.ca \
    --cc=jack@suse.cz \
    --cc=linux-ext4@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=syzbot+4d99a966fd74bdeeec36@syzkaller.appspotmail.com \
    --cc=yebin10@huawei.com \
    --cc=yebin@huaweicloud.com \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox