2021-10-19 19:08:30

by Tim Gardner

[permalink] [raw]
Subject: [PATCH][linux-next] dmaengine: dw-axi-dmac: Fix uninitialized variable in axi_chan_block_xfer_start()

Coverity complains of an uninitialized variable:

5. uninit_use_in_call: Using uninitialized value config.dst_per when calling axi_chan_config_write. [show details]
6. uninit_use_in_call: Using uninitialized value config.hs_sel_src when calling axi_chan_config_write. [show details]
CID 121164 (#1-3 of 3): Uninitialized scalar variable (UNINIT)
7. uninit_use_in_call: Using uninitialized value config.src_per when calling axi_chan_config_write. [show details]
418 axi_chan_config_write(chan, &config);

Fix this by clearing the structure which should at least be benign in axi_chan_config_write(). Also fix
what looks like a cut-n-paste error when initializing config.hs_sel_dst.

Fixes: 824351668a413 ("dmaengine: dw-axi-dmac: support DMAX_NUM_CHANNELS > 8")
Cc: Eugeniy Paltsev <[email protected]>
Cc: Vinod Koul <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Tim Gardner <[email protected]>
---
drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index 79572ec532ef..f47116e77ea1 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -386,12 +386,13 @@ static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,

axi_dma_enable(chan->chip);

+ memset(&config, 0, sizeof(config));
config.dst_multblk_type = DWAXIDMAC_MBLK_TYPE_LL;
config.src_multblk_type = DWAXIDMAC_MBLK_TYPE_LL;
config.tt_fc = DWAXIDMAC_TT_FC_MEM_TO_MEM_DMAC;
config.prior = priority;
config.hs_sel_dst = DWAXIDMAC_HS_SEL_HW;
- config.hs_sel_dst = DWAXIDMAC_HS_SEL_HW;
+ config.hs_sel_src = DWAXIDMAC_HS_SEL_HW;
switch (chan->direction) {
case DMA_MEM_TO_DEV:
dw_axi_dma_set_byte_halfword(chan, true);
--
2.33.1


2021-10-25 05:51:36

by Vinod Koul

[permalink] [raw]
Subject: Re: [PATCH][linux-next] dmaengine: dw-axi-dmac: Fix uninitialized variable in axi_chan_block_xfer_start()

On 19-10-21, 13:07, Tim Gardner wrote:
> Coverity complains of an uninitialized variable:
>
> 5. uninit_use_in_call: Using uninitialized value config.dst_per when calling axi_chan_config_write. [show details]
> 6. uninit_use_in_call: Using uninitialized value config.hs_sel_src when calling axi_chan_config_write. [show details]
> CID 121164 (#1-3 of 3): Uninitialized scalar variable (UNINIT)
> 7. uninit_use_in_call: Using uninitialized value config.src_per when calling axi_chan_config_write. [show details]
> 418 axi_chan_config_write(chan, &config);
>
> Fix this by clearing the structure which should at least be benign in axi_chan_config_write(). Also fix
> what looks like a cut-n-paste error when initializing config.hs_sel_dst.

Eugeniy?

>
> Fixes: 824351668a413 ("dmaengine: dw-axi-dmac: support DMAX_NUM_CHANNELS > 8")
> Cc: Eugeniy Paltsev <[email protected]>
> Cc: Vinod Koul <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Tim Gardner <[email protected]>
> ---
> drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> index 79572ec532ef..f47116e77ea1 100644
> --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
> @@ -386,12 +386,13 @@ static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
>
> axi_dma_enable(chan->chip);
>
> + memset(&config, 0, sizeof(config));

pls init config while defining instead

struct axi_dma_chan_config config = {};

> config.dst_multblk_type = DWAXIDMAC_MBLK_TYPE_LL;
> config.src_multblk_type = DWAXIDMAC_MBLK_TYPE_LL;
> config.tt_fc = DWAXIDMAC_TT_FC_MEM_TO_MEM_DMAC;
> config.prior = priority;
> config.hs_sel_dst = DWAXIDMAC_HS_SEL_HW;
> - config.hs_sel_dst = DWAXIDMAC_HS_SEL_HW;
> + config.hs_sel_src = DWAXIDMAC_HS_SEL_HW;
> switch (chan->direction) {
> case DMA_MEM_TO_DEV:
> dw_axi_dma_set_byte_halfword(chan, true);
> --
> 2.33.1

--
~Vinod

2021-10-25 21:37:56

by Tim Gardner

[permalink] [raw]
Subject: [PATCH v2][linux-next] dmaengine: dw-axi-dmac: Fix uninitialized variable in axi_chan_block_xfer_start()

Coverity complains of an uninitialized variable:

5. uninit_use_in_call: Using uninitialized value config.dst_per when calling axi_chan_config_write. [show details]
6. uninit_use_in_call: Using uninitialized value config.hs_sel_src when calling axi_chan_config_write. [show details]
CID 121164 (#1-3 of 3): Uninitialized scalar variable (UNINIT)
7. uninit_use_in_call: Using uninitialized value config.src_per when calling axi_chan_config_write. [show details]
418 axi_chan_config_write(chan, &config);

Fix this by initializing the structure to 0 which should at least be benign in axi_chan_config_write(). Also fix
what looks like a cut-n-paste error when initializing config.hs_sel_dst.

Fixes: 824351668a413 ("dmaengine: dw-axi-dmac: support DMAX_NUM_CHANNELS > 8")
Cc: Eugeniy Paltsev <[email protected]>
Cc: Vinod Koul <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Tim Gardner <[email protected]>
---

v2 - Use static initializer for 'config'. Drop the memset() call.

---
drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index 79572ec532ef..9a9194da0dcb 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -373,7 +373,7 @@ static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
struct axi_dma_desc *first)
{
u32 priority = chan->chip->dw->hdata->priority[chan->id];
- struct axi_dma_chan_config config;
+ struct axi_dma_chan_config config = {};
u32 irq_mask;
u8 lms = 0; /* Select AXI0 master for LLI fetching */

@@ -391,7 +391,7 @@ static void axi_chan_block_xfer_start(struct axi_dma_chan *chan,
config.tt_fc = DWAXIDMAC_TT_FC_MEM_TO_MEM_DMAC;
config.prior = priority;
config.hs_sel_dst = DWAXIDMAC_HS_SEL_HW;
- config.hs_sel_dst = DWAXIDMAC_HS_SEL_HW;
+ config.hs_sel_src = DWAXIDMAC_HS_SEL_HW;
switch (chan->direction) {
case DMA_MEM_TO_DEV:
dw_axi_dma_set_byte_halfword(chan, true);
--
2.33.1

2021-11-22 05:52:46

by Vinod Koul

[permalink] [raw]
Subject: Re: [PATCH v2][linux-next] dmaengine: dw-axi-dmac: Fix uninitialized variable in axi_chan_block_xfer_start()

On 25-10-21, 12:16, Tim Gardner wrote:
> Coverity complains of an uninitialized variable:
>
> 5. uninit_use_in_call: Using uninitialized value config.dst_per when calling axi_chan_config_write. [show details]
> 6. uninit_use_in_call: Using uninitialized value config.hs_sel_src when calling axi_chan_config_write. [show details]
> CID 121164 (#1-3 of 3): Uninitialized scalar variable (UNINIT)
> 7. uninit_use_in_call: Using uninitialized value config.src_per when calling axi_chan_config_write. [show details]
> 418 axi_chan_config_write(chan, &config);
>
> Fix this by initializing the structure to 0 which should at least be benign in axi_chan_config_write(). Also fix
> what looks like a cut-n-paste error when initializing config.hs_sel_dst.

Applied, thanks

--
~Vinod