[PATCH] fio: fix smalloc strdop allocation failure

[PATCH] fio: fix smalloc strdop allocation failure

[Christian Ehrhardt]

From: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>

smalloc_strdup didn't check for allocation success and thereby ran into
segfaults if the single pool went out of memory.
Now with this patch applied it is still failing, but in a more consistent
way than segfaulting.

You still get a bad allocation, but it looks like this now:
  fio: smalloc OOM
  fio: filesetup.c:1495: dup_files: Assertion `0' failed.
  Aborted

In fact the upper layers expected smalloc_strdup to retrun NULL on failure.

Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
---

[diffstat]
 smalloc.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

[diff]
---
 smalloc.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/smalloc.c
+++ b/smalloc.c
@@ -492,9 +492,10 @@ void *scalloc(size_t nmemb, size_t size)
 
 char *smalloc_strdup(const char *str)
 {
-	char *ptr;
+	char *ptr = NULL;
 
 	ptr = smalloc(strlen(str) + 1);
-	strcpy(ptr, str);
+	if (ptr)
+		strcpy(ptr, str);
 	return ptr;
 }

Re: [PATCH] fio: fix smalloc strdop allocation failure

[Jens Axboe]

On 03/03/2015 04:44 AM, Christian Ehrhardt wrote:
> From: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
>
> smalloc_strdup didn't check for allocation success and thereby ran into
> segfaults if the single pool went out of memory.
> Now with this patch applied it is still failing, but in a more consistent
> way than segfaulting.
>
> You still get a bad allocation, but it looks like this now:
>    fio: smalloc OOM
>    fio: filesetup.c:1495: dup_files: Assertion `0' failed.
>    Aborted
>
> In fact the upper layers expected smalloc_strdup to retrun NULL on failure.
>
> Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>

Applied, thanks.

-- 
Jens Axboe