[Qemu-devel] [PATCH] hw/9pfs/virtio-9p-local.c: use snprintf() instead of sprintf()

[Chen Gang]

We can not assume "'path' + 'ctx->fs_root'" must be less than MAX_PATH,
so need use snprintf() instead of sprintf().

And also recommend to use ARRAY_SIZE instead of hard code macro for an
array size in snprintf().


Signed-off-by: Chen Gang <address@hidden>
---
 hw/9pfs/virtio-9p-local.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/hw/9pfs/virtio-9p-local.c b/hw/9pfs/virtio-9p-local.c
index fc93e9e..44a0380 100644
--- a/hw/9pfs/virtio-9p-local.c
+++ b/hw/9pfs/virtio-9p-local.c
@@ -159,7 +159,7 @@ static int local_create_mapped_attr_dir(FsContext *ctx, 
const char *path)
     char attr_dir[PATH_MAX];
     char *tmp_path = g_strdup(path);
-    snprintf(attr_dir, PATH_MAX, "%s/%s/%s",
+    snprintf(attr_dir, ARRAY_SIZE(attr_dir), "%s/%s/%s",
              ctx->fs_root, dirname(tmp_path), VIRTFS_META_DIR);
      err = mkdir(attr_dir, 0700);
@@ -898,7 +898,8 @@ static int local_remove(FsContext *ctx, const char *path)
          * directory
          */
         if (S_ISDIR(stbuf.st_mode)) {
-            sprintf(buffer, "%s/%s/%s", ctx->fs_root, path, VIRTFS_META_DIR);
+            snprintf(buffer, ARRAY_SIZE(buffer), "%s/%s/%s",
+                     ctx->fs_root, path, VIRTFS_META_DIR);
             err = remove(buffer);
             if (err < 0 && errno != ENOENT) {
                 /*
@@ -1033,8 +1034,8 @@ static int local_unlinkat(FsContext *ctx, V9fsPath *dir,
              * If directory remove .virtfs_metadata contained in the
              * directory
              */
-            sprintf(buffer, "%s/%s/%s", ctx->fs_root,
-                    fullname.data, VIRTFS_META_DIR);
+            snprintf(buffer, ARRAY_SIZE(buffer), "%s/%s/%s", ctx->fs_root,
+                     fullname.data, VIRTFS_META_DIR);
             ret = remove(buffer);
             if (ret < 0 && errno != ENOENT) {
                 /*
-- 
1.7.11.7