Avoid CoverityScan warning SIGN_EXTENSION CID 184096 by changing the type of parameter size of set_cluster().
Avoid leaking stack content when writing an incomplete last sector.
Reported-by: Tom Rini trini@konsulko.com Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de --- fs/fat/fat_write.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-)
diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c index fc211e74bc..5e3aec2d90 100644 --- a/fs/fat/fat_write.c +++ b/fs/fat/fat_write.c @@ -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; }