| From | Greg Kroah-Hartman <> | Subject | [PATCH 4.9 70/74] cdrom: information leak in cdrom_ioctl_media_changed() | Date | Fri, 27 Apr 2018 15:59:00 +0200 |
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4.9-stable review patch. If anyone has any objections, please let me know.
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From: Dan Carpenter <dan.carpenter@oracle.com>
commit 9de4ee40547fd315d4a0ed1dd15a2fa3559ad707 upstream.
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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- drivers/cdrom/cdrom.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/cdrom/cdrom.c +++ b/drivers/cdrom/cdrom.c @@ -2368,7 +2368,7 @@ static int cdrom_ioctl_media_changed(str 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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