All of lore.kernel.org
 help / color / mirror / Atom feed
From: Bart Van Assche <bvanassche@acm.org>
To: "Martin K . Petersen" <martin.petersen@oracle.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>,
	linux-scsi@vger.kernel.org, Bart Van Assche <bvanassche@acm.org>,
	"James E.J. Bottomley" <jejb@linux.ibm.com>,
	Can Guo <cang@codeaurora.org>,
	Stanley Chu <stanley.chu@mediatek.com>,
	Bean Huo <beanhuo@micron.com>, Avri Altman <avri.altman@wdc.com>,
	Asutosh Das <asutoshd@codeaurora.org>
Subject: [PATCH] scsi: ufs: Fix memory corruption by ufshcd_read_desc_param()
Date: Mon, 19 Jul 2021 16:11:22 -0700	[thread overview]
Message-ID: <20210719231127.869088-1-bvanassche@acm.org> (raw)

If param_offset > buff_len then the memcpy() statement in
ufshcd_read_desc_param() corrupts memory since it copies
256 + buff_len - param_offset bytes into a buffer with size buff_len.
Since param_offset < 256 this results in writing past the bound of the
output buffer.

Fixes: cbe193f6f093 ("scsi: ufs: Fix potential NULL pointer access during memcpy")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
 drivers/scsi/ufs/ufshcd.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 89da2cf2c969..00502ffe9b4a 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3365,7 +3365,9 @@ int ufshcd_read_desc_param(struct ufs_hba *hba,
 
 	if (is_kmalloc) {
 		/* Make sure we don't copy more data than available */
-		if (param_offset + param_size > buff_len)
+		if (buff_len < param_offset)
+			param_size = 0;
+		else if (param_offset + param_size > buff_len)
 			param_size = buff_len - param_offset;
 		memcpy(param_read_buf, &desc_buf[param_offset], param_size);
 	}

             reply	other threads:[~2021-07-19 23:39 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-19 23:11 Bart Van Assche [this message]
2021-07-20  6:45 ` [PATCH] scsi: ufs: Fix memory corruption by ufshcd_read_desc_param() Avri Altman
2021-07-20 16:01   ` Bart Van Assche
2021-07-29  3:37 ` Martin K. Petersen
2021-07-29 14:05   ` Bean Huo
2021-07-30  2:56     ` Martin K. Petersen

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=20210719231127.869088-1-bvanassche@acm.org \
    --to=bvanassche@acm.org \
    --cc=asutoshd@codeaurora.org \
    --cc=avri.altman@wdc.com \
    --cc=beanhuo@micron.com \
    --cc=cang@codeaurora.org \
    --cc=jaegeuk@kernel.org \
    --cc=jejb@linux.ibm.com \
    --cc=linux-scsi@vger.kernel.org \
    --cc=martin.petersen@oracle.com \
    --cc=stanley.chu@mediatek.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 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.