drm: bridge: sii8620: fix possible off-by-one

[ Upstream commit 21779cc21c ]

The next call to sii8620_burst_get_tx_buf will result in off-by-one
When ctx->burst.tx_count + size == ARRAY_SIZE(ctx->burst.tx_buf). The same
thing happens in sii8620_burst_get_rx_buf.

This patch also change tx_count and tx_buf to rx_count and rx_buf in
sii8620_burst_get_rx_buf. It is unreasonable to check tx_buf's size and
use rx_buf.

Fixes: e19e9c692f ("drm/bridge/sii8620: add support for burst eMSC transmissions")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220518065856.18936-1-hbh25y@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Hangyu Hua 2022-05-18 14:58:56 +08:00 committed by Greg Kroah-Hartman
parent 966a032cd1
commit 87d8b15bf9

View file

@ -628,7 +628,7 @@ static void *sii8620_burst_get_tx_buf(struct sii8620 *ctx, int len)
u8 *buf = &ctx->burst.tx_buf[ctx->burst.tx_count];
int size = len + 2;
if (ctx->burst.tx_count + size > ARRAY_SIZE(ctx->burst.tx_buf)) {
if (ctx->burst.tx_count + size >= ARRAY_SIZE(ctx->burst.tx_buf)) {
dev_err(ctx->dev, "TX-BLK buffer exhausted\n");
ctx->error = -EINVAL;
return NULL;
@ -645,7 +645,7 @@ static u8 *sii8620_burst_get_rx_buf(struct sii8620 *ctx, int len)
u8 *buf = &ctx->burst.rx_buf[ctx->burst.rx_count];
int size = len + 1;
if (ctx->burst.tx_count + size > ARRAY_SIZE(ctx->burst.tx_buf)) {
if (ctx->burst.rx_count + size >= ARRAY_SIZE(ctx->burst.rx_buf)) {
dev_err(ctx->dev, "RX-BLK buffer exhausted\n");
ctx->error = -EINVAL;
return NULL;