From d03d1021da6fe7f46efe9f2a7335564e7c9db5ab Mon Sep 17 00:00:00 2001

From: Atul Gopinathan <atulgopinathan@gmail.com>

Date: Mon, 3 May 2021 13:56:54 +0200

Subject: [PATCH] cdrom: gdrom: deallocate struct gdrom_unit fields in remove_gdrom

Git-commit: d03d1021da6fe7f46efe9f2a7335564e7c9db5ab

Patch-mainline: v5.13-rc3

References: git-fixes

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@kernel.dk>

Cc: Peter Rosin <peda@axentia.se>

Cc: stable <stable@vger.kernel.org>

Signed-off-by: Atul Gopinathan <atulgopinathan@gmail.com>

Link: https://lore.kernel.org/r/20210503115736.2104747-28-gregkh@linuxfoundation.org

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Acked-by: Takashi Iwai <tiwai@suse.de>

---

 drivers/cdrom/gdrom.c | 3 ++-

 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/cdrom/gdrom.c b/drivers/cdrom/gdrom.c

index 7f681320c7d3..6c4f6139f853 100644

--- a/drivers/cdrom/gdrom.c

+++ b/drivers/cdrom/gdrom.c

@@ -830,6 +830,8 @@ static int remove_gdrom(struct platform_device *devptr)

 	if (gdrom_major)

 		unregister_blkdev(gdrom_major, GDROM_DEV_NAME);

 	unregister_cdrom(gd.cd_info);

+	kfree(gd.cd_info);

+	kfree(gd.toc);

 	return 0;

 }

@@ -861,7 +863,6 @@ static void __exit exit_gdrom(void)

 {

 	platform_device_unregister(pd);

 	platform_driver_unregister(&gdrom_driver);

-	kfree(gd.toc);

 }

 module_init(init_gdrom);

-- 

2.26.2