Libguestfs - Aug 2018 - [PATCH] btrfs_balance_status: delay allocation of 'ret'

Allocate 'ret' as late as possible, so there is no risk that early
returns will leak it.
---
 daemon/btrfs.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/daemon/btrfs.c b/daemon/btrfs.c
index 26757d4fb..5c4be6cf7 100644
--- a/daemon/btrfs.c
+++ b/daemon/btrfs.c
@@ -1683,12 +1683,6 @@ do_btrfs_balance_status (const char *path)
 
   nlines = guestfs_int_count_strings (lines);
 
-  ret = calloc (1, sizeof *ret);
-  if (ret == NULL) {
-    reply_with_perror ("calloc");
-    return NULL;
-  }
-
   /* Output of `btrfs balance status' is like:
    *
    * running:
@@ -1711,6 +1705,12 @@ do_btrfs_balance_status (const char *path)
     return NULL;
   }
 
+  ret = calloc (1, sizeof *ret);
+  if (ret == NULL) {
+    reply_with_perror ("calloc");
+    return NULL;
+  }
+
   if (strstr (lines[0], "No balance found on")) {
     ret->btrfsbalance_status = strdup ("none");
     if (ret->btrfsbalance_status == NULL) {
-- 
2.17.1

On Mon, Aug 06, 2018 at 04:06:55PM +0200, Pino Toscano
wrote:
> Allocate 'ret' as late as possible, so there is no risk that early
> returns will leak it.
> ---
>  daemon/btrfs.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/daemon/btrfs.c b/daemon/btrfs.c
> index 26757d4fb..5c4be6cf7 100644
> --- a/daemon/btrfs.c
> +++ b/daemon/btrfs.c
> @@ -1683,12 +1683,6 @@ do_btrfs_balance_status (const char *path)
>  
>    nlines = guestfs_int_count_strings (lines);
>  
> -  ret = calloc (1, sizeof *ret);
> -  if (ret == NULL) {
> -    reply_with_perror ("calloc");
> -    return NULL;
> -  }
> -
>    /* Output of `btrfs balance status' is like:
>     *
>     * running:
> @@ -1711,6 +1705,12 @@ do_btrfs_balance_status (const char *path)
>      return NULL;
>    }
>  
> +  ret = calloc (1, sizeof *ret);
> +  if (ret == NULL) {
> +    reply_with_perror ("calloc");
> +    return NULL;
> +  }
> +
>    if (strstr (lines[0], "No balance found on")) {
>      ret->btrfsbalance_status = strdup ("none");
>      if (ret->btrfsbalance_status == NULL) {
> -- 
> 2.17.1
ACK, thanks.

Rich.

-- 
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