fs: fat: fix set_cluster()

Avoid CoverityScan warning SIGN_EXTENSION by changing the type of
parameter size of set_cluster().

Avoid leaking stack content when writing an incomplete last sector.

Reported-by: Coverity (CID: 184096)
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
This commit is contained in:
Heinrich Schuchardt 2018-10-02 09:30:45 +02:00 committed by Tom Rini
parent 0d532e911c
commit f105fe7bc5

View file

@ -387,16 +387,22 @@ static __u32 determine_fatent(fsdata *mydata, __u32 entry)
return next_entry;
}
/*
* Write at most 'size' bytes from 'buffer' into the specified cluster.
* Return 0 on success, -1 otherwise.
/**
* set_cluster() - write data to cluster
*
* Write 'size' bytes from 'buffer' into the specified cluster.
*
* @mydata: data to be written
* @clustnum: cluster to be written to
* @buffer: data to be written
* @size: bytes to be written (but not more than the size of a cluster)
* Return: 0 on success, -1 otherwise
*/
static int
set_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer,
unsigned long size)
set_cluster(fsdata *mydata, u32 clustnum, u8 *buffer, u32 size)
{
__u32 idx = 0;
__u32 startsect;
u32 idx = 0;
u32 startsect;
int ret;
if (clustnum > 0)
@ -438,7 +444,8 @@ set_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer,
if (size) {
ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);
/* Do not leak content of stack */
memset(tmpbuf, 0, mydata->sect_size);
memcpy(tmpbuf, buffer, size);
ret = disk_write(startsect, 1, tmpbuf);
if (ret != 1) {
@ -872,7 +879,7 @@ set_clusters:
/* set remaining bytes */
actsize = filesize;
if (set_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
if (set_cluster(mydata, curclust, buffer, (u32)actsize) != 0) {
debug("error: writing cluster\n");
return -1;
}
@ -889,7 +896,7 @@ set_clusters:
return 0;
getit:
if (set_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
if (set_cluster(mydata, curclust, buffer, (u32)actsize) != 0) {
debug("error: writing cluster\n");
return -1;
}