Linux-mtd Archive on lore.kernel.org
 help / color / Atom feed
* [RESEND PATCH] mtd: phram: fix a double free issue in error path
@ 2020-03-18 15:31 Wen Yang
  2020-03-24 22:05 ` Miquel Raynal
  0 siblings, 1 reply; 2+ messages in thread
From: Wen Yang @ 2020-03-18 15:31 UTC (permalink / raw)
  To: Joern Engel, Miquel Raynal, Richard Weinberger, Vignesh Raghavendra
  Cc: linux-mtd, Wen Yang, linux-kernel

The variable 'name' is released multiple times in the error path,
which may cause double free issues.
This problem is avoided by adding a goto label to release the mem
uniformly. And this change also makes the code a bit more cleaner.

Fixes: 4f678a58d335 ("mtd: fix memory leaks in phram_setup")
Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
Cc: Joern Engel <joern@lazybastard.org>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: linux-mtd@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/mtd/devices/phram.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/mtd/devices/phram.c b/drivers/mtd/devices/phram.c
index 931e5c2481b5..b50ec7ecd10c 100644
--- a/drivers/mtd/devices/phram.c
+++ b/drivers/mtd/devices/phram.c
@@ -243,22 +243,25 @@ static int phram_setup(const char *val)
 
 	ret = parse_num64(&start, token[1]);
 	if (ret) {
-		kfree(name);
 		parse_err("illegal start address\n");
+		goto error;
 	}
 
 	ret = parse_num64(&len, token[2]);
 	if (ret) {
-		kfree(name);
 		parse_err("illegal device length\n");
+		goto error;
 	}
 
 	ret = register_device(name, start, len);
-	if (!ret)
-		pr_info("%s device: %#llx at %#llx\n", name, len, start);
-	else
-		kfree(name);
+	if (ret)
+		goto error;
+
+	pr_info("%s device: %#llx at %#llx\n", name, len, start);
+	return 0;
 
+error:
+	kfree(name);
 	return ret;
 }
 
-- 
2.23.0


______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [RESEND PATCH] mtd: phram: fix a double free issue in error path
  2020-03-18 15:31 [RESEND PATCH] mtd: phram: fix a double free issue in error path Wen Yang
@ 2020-03-24 22:05 ` Miquel Raynal
  0 siblings, 0 replies; 2+ messages in thread
From: Miquel Raynal @ 2020-03-24 22:05 UTC (permalink / raw)
  To: Wen Yang, Joern Engel, Miquel Raynal, Richard Weinberger,
	Vignesh Raghavendra
  Cc: linux-mtd, linux-kernel

On Wed, 2020-03-18 at 15:31:56 UTC, Wen Yang wrote:
> The variable 'name' is released multiple times in the error path,
> which may cause double free issues.
> This problem is avoided by adding a goto label to release the mem
> uniformly. And this change also makes the code a bit more cleaner.
> 
> Fixes: 4f678a58d335 ("mtd: fix memory leaks in phram_setup")
> Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
> Cc: Joern Engel <joern@lazybastard.org>
> Cc: Miquel Raynal <miquel.raynal@bootlin.com>
> Cc: Richard Weinberger <richard@nod.at>
> Cc: Vignesh Raghavendra <vigneshr@ti.com>
> Cc: linux-mtd@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git mtd/next, thanks.

Miquel

______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, back to index

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-03-18 15:31 [RESEND PATCH] mtd: phram: fix a double free issue in error path Wen Yang
2020-03-24 22:05 ` Miquel Raynal

Linux-mtd Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-mtd/0 linux-mtd/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-mtd linux-mtd/ https://lore.kernel.org/linux-mtd \
		linux-mtd@lists.infradead.org
	public-inbox-index linux-mtd

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.infradead.lists.linux-mtd


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git