diff mbox series

[ndctl] libcxl: fix a segfault when memdev->pmem is absent

Message ID 20220602154427.462852-1-vishal.l.verma@intel.com (mailing list archive)
State Accepted
Commit 50e7a021314aa0365c9c85a359a31f26313fe93b
Headers show
Series [ndctl] libcxl: fix a segfault when memdev->pmem is absent | expand

Commit Message

Verma, Vishal L June 2, 2022, 3:44 p.m. UTC
A CXL memdev may not have any persistent capacity, and in this case it
is possible that a 'pmem' object never gets instantiated. Such a
scenario would cause free_pmem () to dereference a NULL pointer and
segfault.

Fix this by only proceeding in free_pmem() if 'pmem' was valid.

Fixes: cd1aed6cefe8 ("libcxl: add representation for an nvdimm bridge object")
Reported-by: Steven Garcia <steven.garcia@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
---
 cxl/lib/libcxl.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)


base-commit: 4229f2694e8887a47c636a54130cff0d65f2e995

Comments

Alison Schofield June 15, 2022, 9:46 p.m. UTC | #1
On Thu, Jun 02, 2022 at 09:44:27AM -0600, Vishal Verma wrote:
> A CXL memdev may not have any persistent capacity, and in this case it
> is possible that a 'pmem' object never gets instantiated. Such a
> scenario would cause free_pmem () to dereference a NULL pointer and
> segfault.
> 
> Fix this by only proceeding in free_pmem() if 'pmem' was valid.
> 
> Fixes: cd1aed6cefe8 ("libcxl: add representation for an nvdimm bridge object")
> Reported-by: Steven Garcia <steven.garcia@intel.com>
> Cc: Dan Williams <dan.j.williams@intel.com>
> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
> ---

Reviewed-by: Alison Schofield <alison.schofield@intel.com>

>  cxl/lib/libcxl.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c
> index 1ad4a0b..2578a43 100644
> --- a/cxl/lib/libcxl.c
> +++ b/cxl/lib/libcxl.c
> @@ -50,9 +50,11 @@ struct cxl_ctx {
>  
>  static void free_pmem(struct cxl_pmem *pmem)
>  {
> -	free(pmem->dev_buf);
> -	free(pmem->dev_path);
> -	free(pmem);
> +	if (pmem) {
> +		free(pmem->dev_buf);
> +		free(pmem->dev_path);
> +		free(pmem);
> +	}
>  }
>  
>  static void free_memdev(struct cxl_memdev *memdev, struct list_head *head)
> 
> base-commit: 4229f2694e8887a47c636a54130cff0d65f2e995
> -- 
> 2.36.1
> 
>
diff mbox series

Patch

diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c
index 1ad4a0b..2578a43 100644
--- a/cxl/lib/libcxl.c
+++ b/cxl/lib/libcxl.c
@@ -50,9 +50,11 @@  struct cxl_ctx {
 
 static void free_pmem(struct cxl_pmem *pmem)
 {
-	free(pmem->dev_buf);
-	free(pmem->dev_path);
-	free(pmem);
+	if (pmem) {
+		free(pmem->dev_buf);
+		free(pmem->dev_path);
+		free(pmem);
+	}
 }
 
 static void free_memdev(struct cxl_memdev *memdev, struct list_head *head)