linux-kernel - [PATCH 4.9 22/36] cdrom: gdrom: deallocate struct gdrom_unit fields in remove

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 24 May 2021 17:25:07 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Jens Axboe <axboe@...nel.dk>,
        Peter Rosin <peda@...ntia.se>,
        Atul Gopinathan <atulgopinathan@...il.com>
Subject: [PATCH 4.9 22/36] cdrom: gdrom: deallocate struct gdrom_unit fields in remove_gdrom

From: Atul Gopinathan <atulgopinathan@...il.com>

commit d03d1021da6fe7f46efe9f2a7335564e7c9db5ab upstream.

The fields, "toc" and "cd_info", of "struct gdrom_unit gd" are allocated
in "probe_gdrom()". Prevent a memory leak by making sure "gd.cd_info" is
deallocated in the "remove_gdrom()" function.

Also prevent double free of the field "gd.toc" by moving it from the
module's exit function to "remove_gdrom()". This is because, in
"probe_gdrom()", the function makes sure to deallocate "gd.toc" in case
of any errors, so the exit function invoked later would again free
"gd.toc".

The patch also maintains consistency by deallocating the above mentioned
fields in "remove_gdrom()" along with another memory allocated field
"gd.disk".

Suggested-by: Jens Axboe <axboe@...nel.dk>
Cc: Peter Rosin <peda@...ntia.se>
Cc: stable <stable@...r.kernel.org>
Signed-off-by: Atul Gopinathan <atulgopinathan@...il.com>
Link: https://lore.kernel.org/r/20210503115736.2104747-28-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/cdrom/gdrom.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/cdrom/gdrom.c
+++ b/drivers/cdrom/gdrom.c
@@ -850,6 +850,8 @@ static int remove_gdrom(struct platform_
 	if (gdrom_major)
 		unregister_blkdev(gdrom_major, GDROM_DEV_NAME);
 	unregister_cdrom(gd.cd_info);
+	kfree(gd.cd_info);
+	kfree(gd.toc);

 	return 0;
 }
@@ -881,7 +883,6 @@ static void __exit exit_gdrom(void)
 {
 	platform_device_unregister(pd);
 	platform_driver_unregister(&gdrom_driver);
-	kfree(gd.toc);
 }

 module_init(init_gdrom);