From a1a7ea6bd6d55b6620c9c0a43bf684d6c427172a Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Sun, 30 Apr 2017 16:21:15 -0700 Subject: [PATCH] tools: hv: properly handle long paths Paths can be up to PATH_MAX long and PATH_MAX is usually greater than 256. While on it, simplify path reconstruction to a simple snprintf(), define and reuse KVP_NET_DIR. Suggested-by: Tomas Hozza Signed-off-by: Vitaly Kuznetsov Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman --- tools/hv/hv_kvp_daemon.c | 44 ++++++++++++++++------------------------ 1 file changed, 18 insertions(+), 26 deletions(-) diff --git a/tools/hv/hv_kvp_daemon.c b/tools/hv/hv_kvp_daemon.c index f1758fcbc37d..88b20e007c05 100644 --- a/tools/hv/hv_kvp_daemon.c +++ b/tools/hv/hv_kvp_daemon.c @@ -39,6 +39,7 @@ #include #include #include +#include #include /* @@ -97,6 +98,8 @@ static struct utsname uts_buf; #define KVP_SCRIPTS_PATH "/usr/libexec/hypervkvpd/" #endif +#define KVP_NET_DIR "/sys/class/net/" + #define MAX_FILE_NAME 100 #define ENTRIES_PER_BLOCK 50 @@ -596,26 +599,21 @@ static char *kvp_get_if_name(char *guid) DIR *dir; struct dirent *entry; FILE *file; - char *p, *q, *x; + char *p, *x; char *if_name = NULL; char buf[256]; - char *kvp_net_dir = "/sys/class/net/"; - char dev_id[256]; + char dev_id[PATH_MAX]; - dir = opendir(kvp_net_dir); + dir = opendir(KVP_NET_DIR); if (dir == NULL) return NULL; - snprintf(dev_id, sizeof(dev_id), "%s", kvp_net_dir); - q = dev_id + strlen(kvp_net_dir); - while ((entry = readdir(dir)) != NULL) { /* * Set the state for the next pass. */ - *q = '\0'; - strcat(dev_id, entry->d_name); - strcat(dev_id, "/device/device_id"); + snprintf(dev_id, sizeof(dev_id), "%s%s/device/device_id", + KVP_NET_DIR, entry->d_name); file = fopen(dev_id, "r"); if (file == NULL) @@ -653,12 +651,12 @@ static char *kvp_if_name_to_mac(char *if_name) FILE *file; char *p, *x; char buf[256]; - char addr_file[256]; + char addr_file[PATH_MAX]; unsigned int i; char *mac_addr = NULL; - snprintf(addr_file, sizeof(addr_file), "%s%s%s", "/sys/class/net/", - if_name, "/address"); + snprintf(addr_file, sizeof(addr_file), "%s%s%s", KVP_NET_DIR, + if_name, "/address"); file = fopen(addr_file, "r"); if (file == NULL) @@ -688,28 +686,22 @@ static char *kvp_mac_to_if_name(char *mac) DIR *dir; struct dirent *entry; FILE *file; - char *p, *q, *x; + char *p, *x; char *if_name = NULL; char buf[256]; - char *kvp_net_dir = "/sys/class/net/"; - char dev_id[256]; + char dev_id[PATH_MAX]; unsigned int i; - dir = opendir(kvp_net_dir); + dir = opendir(KVP_NET_DIR); if (dir == NULL) return NULL; - snprintf(dev_id, sizeof(dev_id), "%s", kvp_net_dir); - q = dev_id + strlen(kvp_net_dir); - while ((entry = readdir(dir)) != NULL) { /* * Set the state for the next pass. */ - *q = '\0'; - - strcat(dev_id, entry->d_name); - strcat(dev_id, "/address"); + snprintf(dev_id, sizeof(dev_id), "%s%s/address", KVP_NET_DIR, + entry->d_name); file = fopen(dev_id, "r"); if (file == NULL) @@ -1218,9 +1210,9 @@ static int process_ip_string(FILE *f, char *ip_string, int type) static int kvp_set_ip_info(char *if_name, struct hv_kvp_ipaddr_value *new_val) { int error = 0; - char if_file[128]; + char if_file[PATH_MAX]; FILE *file; - char cmd[512]; + char cmd[PATH_MAX]; char *mac_addr; /* -- 2.20.1