From 40fe714ca4245a9716264fcb3ee8df42c3650cf6 Mon Sep 17 00:00:00 2001 From: Bertrand Marquis Date: Wed, 7 Oct 2020 14:57:01 +0100 Subject: [PATCH] tools/libs/stat: use memcpy instead of strncpy in getBridge Use memcpy in getBridge to prevent gcc warnings about truncated strings. We know that we might truncate it, so the gcc warning here is wrong. Revert previous change changing buffer sizes as bigger buffers are not needed. Signed-off-by: Bertrand Marquis Acked-by: Wei Liu --- tools/libs/stat/xenstat_linux.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/tools/libs/stat/xenstat_linux.c b/tools/libs/stat/xenstat_linux.c index d2ee6fda64..e0d242e1bc 100644 --- a/tools/libs/stat/xenstat_linux.c +++ b/tools/libs/stat/xenstat_linux.c @@ -29,6 +29,7 @@ #include #include #include +#include #include "xenstat_priv.h" @@ -78,8 +79,14 @@ static void getBridge(char *excludeName, char *result, size_t resultLen) sprintf(tmp, "/sys/class/net/%s/bridge", de->d_name); if (access(tmp, F_OK) == 0) { - strncpy(result, de->d_name, resultLen); - result[resultLen - 1] = 0; + /* + * Do not use strncpy to prevent compiler warning with + * gcc >= 10.0 + * If de->d_name is longer then resultLen we truncate it + */ + memset(result, 0, resultLen); + memcpy(result, de->d_name, MIN(strnlen(de->d_name, + NAME_MAX),resultLen - 1)); } } } @@ -264,7 +271,7 @@ int xenstat_collect_networks(xenstat_node * node) { /* Helper variables for parseNetDevLine() function defined above */ int i; - char line[512] = { 0 }, iface[16] = { 0 }, devBridge[256] = { 0 }, devNoBridge[257] = { 0 }; + char line[512] = { 0 }, iface[16] = { 0 }, devBridge[16] = { 0 }, devNoBridge[17] = { 0 }; unsigned long long rxBytes, rxPackets, rxErrs, rxDrops, txBytes, txPackets, txErrs, txDrops; struct priv_data *priv = get_priv_data(node->handle); -- 2.30.2