[PATCH] cxl: Release irqs if memory allocation fails

[PATCH] cxl: Release irqs if memory allocation fails

[Vaibhav Jain]

This minor patch plugs a potential irq leak in case of a memory
allocation failure inside function the afu_allocate_irqs. Presently the
irqs allocated to the context gets leaked if allocation of either
one of context irq_bitmap or irq_names fails.

Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
---
 drivers/misc/cxl/irq.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/misc/cxl/irq.c b/drivers/misc/cxl/irq.c
index c8f1f9d..e8b887e 100644
--- a/drivers/misc/cxl/irq.c
+++ b/drivers/misc/cxl/irq.c
@@ -421,6 +421,9 @@ int afu_allocate_irqs(struct cxl_context *ctx, u32 count)
 	int rc, r, i, j = 1;
 	struct cxl_irq_name *irq_name;
 
+	/* Initialize the list head to hold irq names */
+	INIT_LIST_HEAD(&ctx->irq_names);
+
 	if ((rc = cxl_alloc_irq_ranges(&ctx->irqs, ctx->afu->adapter, count)))
 		return rc;
 
@@ -432,13 +435,12 @@ int afu_allocate_irqs(struct cxl_context *ctx, u32 count)
 	ctx->irq_bitmap = kcalloc(BITS_TO_LONGS(count),
 				  sizeof(*ctx->irq_bitmap), GFP_KERNEL);
 	if (!ctx->irq_bitmap)
-		return -ENOMEM;
+		goto out;
 
 	/*
 	 * Allocate names first.  If any fail, bail out before allocating
 	 * actual hardware IRQs.
 	 */
-	INIT_LIST_HEAD(&ctx->irq_names);
 	for (r = 1; r < CXL_IRQ_RANGES; r++) {
 		for (i = 0; i < ctx->irqs.range[r]; i++) {
 			irq_name = kmalloc(sizeof(struct cxl_irq_name),
@@ -460,6 +462,7 @@ int afu_allocate_irqs(struct cxl_context *ctx, u32 count)
 	return 0;
 
 out:
+	cxl_release_irq_ranges(&ctx->irqs, ctx->afu->adapter);
 	afu_irq_name_free(ctx);
 	return -ENOMEM;
 }
-- 
2.2.1

Re: [PATCH] cxl: Release irqs if memory allocation fails

[Ian Munsie]

Acked-by: Ian Munsie <imunsie@au1.ibm.com>

Re: cxl: Release irqs if memory allocation fails

[Michael Ellerman]

On Tue, 2015-25-08 at 05:34:48 UTC, Vaibhav Jain wrote:
> This minor patch plugs a potential irq leak in case of a memory
> allocation failure inside function the afu_allocate_irqs. Presently the
> irqs allocated to the context gets leaked if allocation of either
> one of context irq_bitmap or irq_names fails.
> 
> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
> Acked-by: Ian Munsie <imunsie@au1.ibm.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/a6897f39660cc07fa78b4459

cheers