From 1ba4de17e0cb9cc3e03ce5b1fafebdd01c48c1f2 Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Tue, 12 May 2015 14:49:41 -0700 Subject: [PATCH] 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 Cc: Ming Lei Cc: Rusty Russell Cc: David Howells Cc: Kyle McMartin Signed-off-by: Luis R. Rodriguez Signed-off-by: Greg Kroah-Hartman --- drivers/base/firmware_class.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index 49139a1ee25e..9ffa70762473 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -320,7 +320,7 @@ fail: 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))