[ 05/18] xhci: check for failed dma pool allocation

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

3.0-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Mathias Nyman <mathias.nyman@linux.intel.com>

commit 025f880cb2e4d7218d0422d4b07bea1a68959c38 upstream.

Fail and free the container context in case dma_pool_alloc() can't allocate
the raw context data part of it

This patch should be backported to kernels as old as 2.6.31, that
contain the commit d115b04818e57bdbc7ccde4d0660b15e33013dc8 "USB: xhci:
Support for 64-byte contexts".

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: John Youn <johnyoun@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/host/xhci-mem.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -273,6 +273,10 @@ static struct xhci_container_ctx *xhci_a
 		ctx->size += CTX_SIZE(xhci->hcc_params);
 
 	ctx->bytes = dma_pool_alloc(xhci->device_pool, flags, &ctx->dma);
+	if (!ctx->bytes) {
+		kfree(ctx);
+		return NULL;
+	}
 	memset(ctx->bytes, 0, ctx->size);
 	return ctx;
 }