From: Juan Zea Date: Fri, 15 Dec 2017 09:21:20 +0000 (+0100) Subject: usbip: fix usbip bind writing random string after command in match_busid X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=10a272f0242add15497e485c8d8bf31debd5ab20;p=pandora-kernel.git usbip: fix usbip bind writing random string after command in match_busid commit 544c4605acc5ae4afe7dd5914147947db182f2fb upstream. usbip bind writes commands followed by random string when writing to match_busid attribute in sysfs, caused by using full variable size instead of string length. Signed-off-by: Juan Zea Acked-by: Shuah Khan Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- diff --git a/drivers/staging/usbip/userspace/src/utils.c b/drivers/staging/usbip/userspace/src/utils.c index 2d4966e6289c..a52189fa1609 100644 --- a/drivers/staging/usbip/userspace/src/utils.c +++ b/drivers/staging/usbip/userspace/src/utils.c @@ -34,6 +34,7 @@ int modify_match_busid(char *busid, int add) char match_busid_attr_path[SYSFS_PATH_MAX]; struct sysfs_attribute *match_busid_attr; int rc, ret = 0; + int cmd_size; if (strnlen(busid, SYSFS_BUS_ID_SIZE) > SYSFS_BUS_ID_SIZE - 1) { dbg("busid is too long"); @@ -58,13 +59,15 @@ int modify_match_busid(char *busid, int add) } if (add) - snprintf(buff, SYSFS_BUS_ID_SIZE + 4, "add %s", busid); + cmd_size = snprintf(buff, SYSFS_BUS_ID_SIZE + 4, "add %s", + busid); else - snprintf(buff, SYSFS_BUS_ID_SIZE + 4, "del %s", busid); + cmd_size = snprintf(buff, SYSFS_BUS_ID_SIZE + 4, "del %s", + busid); dbg("write \"%s\" to %s", buff, match_busid_attr->path); - rc = sysfs_write_attribute(match_busid_attr, buff, sizeof(buff)); + rc = sysfs_write_attribute(match_busid_attr, buff, cmd_size); if (rc < 0) { dbg("failed to write match_busid: %s", strerror(errno)); ret = -1;