ocxl: Fix potential memory leak on context creation

If we couldn't fully init a context, we were leaking memory.

Fixes: b9721d275cc2 ("ocxl: Allow external drivers to use OpenCAPI contexts")
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191209105513.8566-1-fbarrat@linux.ibm.com

diff --git a/drivers/misc/ocxl/context.c b/drivers/misc/ocxl/context.c
index 994563a..de8a66b 100644 (file)
--- a/drivers/misc/ocxl/context.c
+++ b/drivers/misc/ocxl/context.c
@@ -10,18 +10,17 @@ int ocxl_context_alloc(struct ocxl_context **context, struct ocxl_afu *afu,
        int pasid;
        struct ocxl_context *ctx;
 
-       *context = kzalloc(sizeof(struct ocxl_context), GFP_KERNEL);
-       if (!*context)
+       ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+       if (!ctx)
                return -ENOMEM;
 
-       ctx = *context;
-
        ctx->afu = afu;
        mutex_lock(&afu->contexts_lock);
        pasid = idr_alloc(&afu->contexts_idr, ctx, afu->pasid_base,
                        afu->pasid_base + afu->pasid_max, GFP_KERNEL);
        if (pasid < 0) {
                mutex_unlock(&afu->contexts_lock);
+               kfree(ctx);
                return pasid;
        }
        afu->pasid_count++;
@@ -43,6 +42,7 @@ int ocxl_context_alloc(struct ocxl_context **context, struct ocxl_afu *afu,
         * duration of the life of the context
         */
        ocxl_afu_get(afu);
+       *context = ctx;
        return 0;
 }
 EXPORT_SYMBOL_GPL(ocxl_context_alloc);