Commit 1ba4de17 authored May 12, 2015 by Luis R. Rodriguez Committed by Greg Kroah-Hartman May 24, 2015

firmware: check for file truncation on direct firmware loading



When direct firmware loading is used we iterate over a list
of possible firmware paths and concatenate the desired firmware
name with each path and look for the file there. Should the
passed firmware name be too long we end up truncating the
file we want to look for, the search however is still done.
Add a check for truncation instead of looking for a
truncated firmware filename.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@kernel.org>
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent f5727b05

drivers/base/firmware_class.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -320,7 +320,7 @@ static int fw_read_file_contents(struct file file, struct firmware_buf fw_buf)
		static int fw_get_filesystem_firmware(struct device *device,
		struct firmware_buf *buf)
		{
		int i;
		int i, len;
		int rc = -ENOENT;
		char *path;

		@@ -335,7 +335,12 @@ static int fw_get_filesystem_firmware(struct device *device,
		if (!fw_path[i][0])
		continue;

		snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
		len = snprintf(path, PATH_MAX, "%s/%s",
		fw_path[i], buf->fw_id);
		if (len >= PATH_MAX) {
		rc = -ENAMETOOLONG;
		break;
		}

		file = filp_open(path, O_RDONLY, 0);
		if (IS_ERR(file))