firmware: use 'kernel_read()' to read firmware into kernel buffer
Fengguang correctly points out that the firmware reading should not use
vfs_read(), since the buffer is in kernel space.
The vfs_read() just happened to work for kernel threads, but sparse
warns about the incorrect address spaces, and it's definitely incorrect
and could fail for other users of the firmware loading.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index e85763d..8154145 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -58,7 +58,6 @@
static bool fw_read_file_contents(struct file *file, struct firmware *fw)
{
- loff_t pos;
long size;
char *buf;
@@ -68,8 +67,7 @@
buf = vmalloc(size);
if (!buf)
return false;
- pos = 0;
- if (vfs_read(file, buf, size, &pos) != size) {
+ if (kernel_read(file, 0, buf, size) != size) {
vfree(buf);
return false;
}
