summaryrefslogtreecommitdiff
path: root/tools/hv
diff options
context:
space:
mode:
authorDexuan Cui <decui@microsoft.com>2018-10-18 08:09:32 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-11-11 23:58:27 +0300
commit4fcba7802c3e15a6e56e255871d6c72f829b9dd8 (patch)
treed12b055179213bb74dc40efaadc757943141f49b /tools/hv
parent16d1342bc41ad417812f8a800a1799b5d1c026dc (diff)
downloadlinux-4fcba7802c3e15a6e56e255871d6c72f829b9dd8.tar.xz
Tools: hv: kvp: Fix a warning of buffer overflow with gcc 8.0.1
The patch fixes: hv_kvp_daemon.c: In function 'kvp_set_ip_info': hv_kvp_daemon.c:1305:2: note: 'snprintf' output between 41 and 4136 bytes into a destination of size 4096 The "(unsigned int)str_len" is to avoid: hv_kvp_daemon.c:1309:30: warning: comparison of integer expressions of different signedness: 'int' and 'long unsigned int' [-Wsign-compare] Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'tools/hv')
-rw-r--r--tools/hv/hv_kvp_daemon.c15
1 files changed, 13 insertions, 2 deletions
diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c
index bbb2a8ef367c..d7e06fe0270e 100644
--- a/tools/hv/hv_kvp_daemon.c
+++ b/tools/hv/hv_kvp_daemon.c
@@ -1178,6 +1178,7 @@ static int kvp_set_ip_info(char *if_name, struct hv_kvp_ipaddr_value *new_val)
FILE *file;
char cmd[PATH_MAX];
char *mac_addr;
+ int str_len;
/*
* Set the configuration for the specified interface with
@@ -1301,8 +1302,18 @@ static int kvp_set_ip_info(char *if_name, struct hv_kvp_ipaddr_value *new_val)
* invoke the external script to do its magic.
*/
- snprintf(cmd, sizeof(cmd), KVP_SCRIPTS_PATH "%s %s",
- "hv_set_ifconfig", if_file);
+ str_len = snprintf(cmd, sizeof(cmd), KVP_SCRIPTS_PATH "%s %s",
+ "hv_set_ifconfig", if_file);
+ /*
+ * This is a little overcautious, but it's necessary to suppress some
+ * false warnings from gcc 8.0.1.
+ */
+ if (str_len <= 0 || (unsigned int)str_len >= sizeof(cmd)) {
+ syslog(LOG_ERR, "Cmd '%s' (len=%d) may be too long",
+ cmd, str_len);
+ return HV_E_FAIL;
+ }
+
if (system(cmd)) {
syslog(LOG_ERR, "Failed to execute cmd '%s'; error: %d %s",
cmd, errno, strerror(errno));