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>
This commit is contained in:
Linus Torvalds 2012-10-04 09:19:02 -07:00
parent e1cc485262
commit ce57e981f2

View File

@ -58,7 +58,6 @@ static noinline long fw_file_size(struct file *file)
static bool fw_read_file_contents(struct file *file, struct firmware *fw)
{
loff_t pos;
long size;
char *buf;
@ -68,8 +67,7 @@ static bool fw_read_file_contents(struct file *file, struct firmware *fw)
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;
}