ipr: Fix out-of-bounds null overwrite

Return value of snprintf is not bound by size value, 2nd argument.
(https://www.kernel.org/doc/htmldocs/kernel-api/API-snprintf.html).
Return value is number of printed chars, can be larger than 2nd
argument.  Therefore, it can write null byte out of bounds ofbuffer.
Since snprintf puts null, it does not need to put additional null byte.

Signed-off-by: Insu Yun <wuninsu@gmail.com>
Reviewed-by: Shane Seymour <shane.seymour@hpe.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Insu Yun 2016-01-06 12:44:01 -05:00 committed by Martin K. Petersen
parent 9055082fb1
commit d63c7dd5bc

View File

@ -4003,13 +4003,12 @@ static ssize_t ipr_store_update_fw(struct device *dev,
struct ipr_sglist *sglist;
char fname[100];
char *src;
int len, result, dnld_size;
int result, dnld_size;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
len = snprintf(fname, 99, "%s", buf);
fname[len-1] = '\0';
snprintf(fname, sizeof(fname), "%s", buf);
if (request_firmware(&fw_entry, fname, &ioa_cfg->pdev->dev)) {
dev_err(&ioa_cfg->pdev->dev, "Firmware file %s not found\n", fname);