[PATCH v2 2/2] mmc: cqhci: Fix a tiny potential memory leak on error condition

From: Alamy Liu
Date: Mon Feb 25 2019 - 14:22:22 EST


Free up the allocated memory in the case of error return

--- code study ---
The value of mmc_host->cqe_enabled stays 'false'.
Thus, cqhci_disable (mmc_cqe_ops->cqe_disable) won't be called to
free the memory.
Also, cqhci_disable() seems to be designed to disable and free
all resources, not suitable to handle this corner case.

Fixes: a4080225f51d ("mmc: cqhci: support for command queue enabled host")
Signed-off-by: Alamy Liu <alamy.liu@xxxxxxxxx>
---
drivers/mmc/host/cqhci.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/cqhci.c b/drivers/mmc/host/cqhci.c
index 974997b6cb..795893ba47 100644
--- a/drivers/mmc/host/cqhci.c
+++ b/drivers/mmc/host/cqhci.c
@@ -218,12 +218,21 @@ static int cqhci_host_alloc_tdl(struct cqhci_host *cq_host)
cq_host->desc_size,
&cq_host->desc_dma_base,
GFP_KERNEL);
+ if (!cq_host->desc_base)
+ return -ENOMEM;
+
cq_host->trans_desc_base = dmam_alloc_coherent(mmc_dev(cq_host->mmc),
cq_host->data_size,
&cq_host->trans_desc_dma_base,
GFP_KERNEL);
- if (!cq_host->desc_base || !cq_host->trans_desc_base)
+ if (!cq_host->trans_desc_base) {
+ dmam_free_coherent(mmc_dev(cq_host->mmc), cq_host->desc_size,
+ cq_host->desc_base,
+ cq_host->desc_dma_base);
+ cq_host->desc_base = NULL;
+ cq_host->desc_dma_base = 0;
return -ENOMEM;
+ }

pr_debug("%s: cqhci: desc-base: 0x%p trans-base: 0x%p\n desc_dma 0x%llx trans_dma: 0x%llx\n",
mmc_hostname(cq_host->mmc), cq_host->desc_base, cq_host->trans_desc_base,
--
2.17.1