From: Insu Yun Date: Wed, 6 Jan 2016 17:44:01 +0000 (-0500) Subject: ipr: Fix out-of-bounds null overwrite X-Git-Tag: MMI-PSA29.97-13-9~8625^2^2~8 X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d63c7dd5bcb9;p=GitHub%2FMotorolaMobilityLLC%2Fkernel-slsi.git 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 Reviewed-by: Shane Seymour Signed-off-by: Martin K. Petersen --- diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c index 536cd5a80422..1c3759bab80b 100644 --- a/drivers/scsi/ipr.c +++ b/drivers/scsi/ipr.c @@ -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);