mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Khazhismel Kumykov <khazhy@google.com>
To: axboe@kernel.dk
Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
	Khazhismel Kumykov <khazhy@google.com>
Subject: [PATCH] block/compat_ioctl: fix range check in BLKGETSIZE
Date: Fri,  6 Apr 2018 15:23:50 -0700	[thread overview]
Message-ID: <20180406222350.174104-1-khazhy@google.com> (raw)

[-- Attachment #1: Type: text/plain, Size: 806 bytes --]

kernel ulong and compat_ulong_t may not be same width. Use type directly
to eliminate mismatches.

This would result in truncation rather than EFBIG for 32bit mode for
large disks.

Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
---
 block/compat_ioctl.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c
index 6ca015f92766..3a2c77f07da8 100644
--- a/block/compat_ioctl.c
+++ b/block/compat_ioctl.c
@@ -388,7 +388,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 		return 0;
 	case BLKGETSIZE:
 		size = i_size_read(bdev->bd_inode);
-		if ((size >> 9) > ~0UL)
+		if ((size >> 9) > ~((compat_ulong_t)0UL))
 			return -EFBIG;
 		return compat_put_ulong(arg, size >> 9);
 
-- 
2.17.0.484.g0c8726318c-goog


[-- Attachment #2: S/MIME Cryptographic Signature --]
[-- Type: application/pkcs7-signature, Size: 4843 bytes --]

             reply	other threads:[~2018-04-06 22:25 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-06 22:23 Khazhismel Kumykov [this message]
2018-07-31 18:23 ` Khazhismel Kumykov
2018-08-02 21:31 ` Jens Axboe
2022-04-08 23:47 Khazhismel Kumykov
2022-04-09 21:33 ` Bart Van Assche

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=20180406222350.174104-1-khazhy@google.com \
    --to=khazhy@google.com \
    --cc=axboe@kernel.dk \
    --cc=linux-block@vger.kernel.org \
    --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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome