Fix potential device string truncation

While compiling using gcc 7.1.1 I ran into compile errors, eg.

nvme.c: In function ‘scan_dev_filter.part.5’:
nvme.c:797:35: error: ‘%s’ directive output may be truncated writing " \
   "up to 255 bytes into a region of size 251 [-Werror=format-truncation=]
   snprintf(path, sizeof(path), "%s%s", dev, d->d_name);

This is caused because the buffer on the stack is only 256 bytes and the
dirent.d_name is 256 and the constant string is "/dev/", so  256 + 5,
but I've rounded up to nearest 4/8 byte alignment of 264.

Signed-off-by: Tony Asleson <tasleson@redhat.com>

diff --git a/huawei-nvme.c b/huawei-nvme.c
index 91de34ebc51de7fdae751581cdcdd54f984fd2b6..f9415338c7863eab19a63dc74981e8319553d35c 100644 (file)
--- a/huawei-nvme.c
+++ b/huawei-nvme.c
@@ -71,7 +71,7 @@ static const char *dev = "/dev/";
 /* Assume every block device starting with /dev/nvme is an nvme namespace */
 static int huawei_scan_dev_filter(const struct dirent *d)
 {
-       char path[256];
+       char path[264];
        struct stat bd;
        int ctrl, ns, part;
 
@@ -318,7 +318,7 @@ static void huawei_print_list_items(struct huawei_list_item *list_items, unsigne
 static int huawei_list(int argc, char **argv, struct command *command,
                struct plugin *plugin)
 {
-       char path[256];
+       char path[264];
        struct dirent **devices;
        struct huawei_list_item *list_items;
        unsigned int i, n, fd, ret;

diff --git a/nvme.c b/nvme.c
index c2196346965e0cacce2ff8200cd16f4a4930f7da..98f96be8aab14909d4e95d3188cfd34a2fc66928 100644 (file)
--- a/nvme.c
+++ b/nvme.c
@@ -786,7 +786,7 @@ static const char *dev = "/dev/";
 /* Assume every block device starting with /dev/nvme is an nvme namespace */
 static int scan_dev_filter(const struct dirent *d)
 {
-       char path[256];
+       char path[264];
        struct stat bd;
        int ctrl, ns, part;
 
@@ -808,7 +808,7 @@ static int scan_dev_filter(const struct dirent *d)
 
 static int list(int argc, char **argv, struct command *cmd, struct plugin *plugin)
 {
-       char path[256];
+       char path[264];
        struct dirent **devices;
        struct list_item *list_items;
        unsigned int i, n, fd, ret;