[PATCH v2 5.2] rsi: Properly initialize data in rsi_sdio_ta_reset

From: Nathan Chancellor
Date: Thu May 23 2019 - 11:34:22 EST


When building with -Wuninitialized, Clang warns:

drivers/net/wireless/rsi/rsi_91x_sdio.c:940:43: warning: variable 'data'
is uninitialized when used here [-Wuninitialized]
put_unaligned_le32(TA_HOLD_THREAD_VALUE, data);
^~~~
drivers/net/wireless/rsi/rsi_91x_sdio.c:930:10: note: initialize the
variable 'data' to silence this warning
u8 *data;
^
= NULL
1 warning generated.

Using Clang's suggestion of initializing data to NULL wouldn't work out
because data will be dereferenced by put_unaligned_le32. Use kzalloc to
properly initialize data, which matches a couple of other places in this
driver.

Fixes: e5a1ecc97e5f ("rsi: add firmware loading for 9116 device")
Link: https://github.com/ClangBuiltLinux/linux/issues/464
Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
---

v1 -> v2:

* Use RSI_9116_REG_SIZE instead of sizeof(u32) for kzalloc thanks to
review from Arnd.

drivers/net/wireless/rsi/rsi_91x_sdio.c | 21 ++++++++++++++-------
1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/rsi/rsi_91x_sdio.c b/drivers/net/wireless/rsi/rsi_91x_sdio.c
index f9c67ed473d1..b42cd50b837e 100644
--- a/drivers/net/wireless/rsi/rsi_91x_sdio.c
+++ b/drivers/net/wireless/rsi/rsi_91x_sdio.c
@@ -929,11 +929,15 @@ static int rsi_sdio_ta_reset(struct rsi_hw *adapter)
u32 addr;
u8 *data;

+ data = kzalloc(RSI_9116_REG_SIZE, GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
status = rsi_sdio_master_access_msword(adapter, TA_BASE_ADDR);
if (status < 0) {
rsi_dbg(ERR_ZONE,
"Unable to set ms word to common reg\n");
- return status;
+ goto err;
}

rsi_dbg(INIT_ZONE, "%s: Bring TA out of reset\n", __func__);
@@ -944,7 +948,7 @@ static int rsi_sdio_ta_reset(struct rsi_hw *adapter)
RSI_9116_REG_SIZE);
if (status < 0) {
rsi_dbg(ERR_ZONE, "Unable to hold TA threads\n");
- return status;
+ goto err;
}

put_unaligned_le32(TA_SOFT_RST_CLR, data);
@@ -954,7 +958,7 @@ static int rsi_sdio_ta_reset(struct rsi_hw *adapter)
RSI_9116_REG_SIZE);
if (status < 0) {
rsi_dbg(ERR_ZONE, "Unable to get TA out of reset\n");
- return status;
+ goto err;
}

put_unaligned_le32(TA_PC_ZERO, data);
@@ -964,7 +968,8 @@ static int rsi_sdio_ta_reset(struct rsi_hw *adapter)
RSI_9116_REG_SIZE);
if (status < 0) {
rsi_dbg(ERR_ZONE, "Unable to Reset TA PC value\n");
- return -EINVAL;
+ status = -EINVAL;
+ goto err;
}

put_unaligned_le32(TA_RELEASE_THREAD_VALUE, data);
@@ -974,17 +979,19 @@ static int rsi_sdio_ta_reset(struct rsi_hw *adapter)
RSI_9116_REG_SIZE);
if (status < 0) {
rsi_dbg(ERR_ZONE, "Unable to release TA threads\n");
- return status;
+ goto err;
}

status = rsi_sdio_master_access_msword(adapter, MISC_CFG_BASE_ADDR);
if (status < 0) {
rsi_dbg(ERR_ZONE, "Unable to set ms word to common reg\n");
- return status;
+ goto err;
}
rsi_dbg(INIT_ZONE, "***** TA Reset done *****\n");

- return 0;
+err:
+ kfree(data);
+ return status;
}

static struct rsi_host_intf_ops sdio_host_intf_ops = {
--
2.22.0.rc1