Commit 9de4ee40 authored Apr 18, 2018 by Dan Carpenter Committed by Jens Axboe Apr 18, 2018

cdrom: information leak in cdrom_ioctl_media_changed()



This cast is wrong.  "cdi->capacity" is an int and "arg" is an unsigned
long.  The way the check is written now, if one of the high 32 bits is
set then we could read outside the info->slots[] array.

This bug is pretty old and it predates git.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent 72961c4e

drivers/cdrom/cdrom.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -2371,7 +2371,7 @@ static int cdrom_ioctl_media_changed(struct cdrom_device_info *cdi,
		if (!CDROM_CAN(CDC_SELECT_DISC) \|\| arg == CDSL_CURRENT)
		return media_changed(cdi, 1);

		if ((unsigned int)arg >= cdi->capacity)
		if (arg >= cdi->capacity)
		return -EINVAL;

		info = kmalloc(sizeof(*info), GFP_KERNEL);

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