2018-01-12 17:46:36

by Colin King

Subject: [PATCH][next] bnxt_en: ensure len is ininitialized to zero

From: Colin Ian King <[email protected]>

In the case where cmp_type == CMP_TYPE_RX_L2_TPA_START_CMP the
exit return path is via label next_rx_no_prod and cpr->rx_bytes
is being updated by an uninitialized value from len. Fix this by
initializing len to zero.

Detected by CoverityScan, CID#1463807 ("Uninitialized scalar variable")

Fixes: 6a8788f25625 ("bnxt_en: add support for software dynamic interrupt moderation")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/net/ethernet/broadcom/bnxt/bnxt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index cf6ebf1e324b..5b5c4f266f1b 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -1482,7 +1482,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
u32 tmp_raw_cons = *raw_cons;
u16 cfa_code, cons, prod, cp_cons = RING_CMP(tmp_raw_cons);
struct bnxt_sw_rx_bd *rx_buf;
- unsigned int len;
+ unsigned int len = 0;
u8 *data_ptr, agg_bufs, cmp_type;
dma_addr_t dma_addr;
struct sk_buff *skb;
--
2.15.1

2018-01-12 18:11:20

by Michael Chan

Subject: Re: [PATCH][next] bnxt_en: ensure len is ininitialized to zero

On Fri, Jan 12, 2018 at 9:46 AM, Colin King <[email protected]> wrote:
> From: Colin Ian King <[email protected]>
>
> In the case where cmp_type == CMP_TYPE_RX_L2_TPA_START_CMP the
> exit return path is via label next_rx_no_prod and cpr->rx_bytes
> is being updated by an uninitialized value from len. Fix this by
> initializing len to zero.
>
> Detected by CoverityScan, CID#1463807 ("Uninitialized scalar variable")
>
> Fixes: 6a8788f25625 ("bnxt_en: add support for software dynamic interrupt moderation")
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/net/ethernet/broadcom/bnxt/bnxt.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> index cf6ebf1e324b..5b5c4f266f1b 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> @@ -1482,7 +1482,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
> u32 tmp_raw_cons = *raw_cons;
> u16 cfa_code, cons, prod, cp_cons = RING_CMP(tmp_raw_cons);
> struct bnxt_sw_rx_bd *rx_buf;
> - unsigned int len;
> + unsigned int len = 0;

It might be better to add a new label next_rx_no_prod_no_len and have
the TPA code paths jump there instead.

Andy, what do you think?

> u8 *data_ptr, agg_bufs, cmp_type;
> dma_addr_t dma_addr;
> struct sk_buff *skb;
> --
> 2.15.1
>

2018-01-12 22:39:00

by Andy Gospodarek

Subject: Re: [PATCH][next] bnxt_en: ensure len is ininitialized to zero

On Fri, Jan 12, 2018 at 10:11:17AM -0800, Michael Chan wrote:
> On Fri, Jan 12, 2018 at 9:46 AM, Colin King <[email protected]> wrote:
> > From: Colin Ian King <[email protected]>
> >
> > In the case where cmp_type == CMP_TYPE_RX_L2_TPA_START_CMP the
> > exit return path is via label next_rx_no_prod and cpr->rx_bytes
> > is being updated by an uninitialized value from len. Fix this by
> > initializing len to zero.
> >
> > Detected by CoverityScan, CID#1463807 ("Uninitialized scalar variable")
> >
> > Fixes: 6a8788f25625 ("bnxt_en: add support for software dynamic interrupt moderation")
> > Signed-off-by: Colin Ian King <[email protected]>
> > ---
> > drivers/net/ethernet/broadcom/bnxt/bnxt.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> > index cf6ebf1e324b..5b5c4f266f1b 100644
> > --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> > +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> > @@ -1482,7 +1482,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
> > u32 tmp_raw_cons = *raw_cons;
> > u16 cfa_code, cons, prod, cp_cons = RING_CMP(tmp_raw_cons);
> > struct bnxt_sw_rx_bd *rx_buf;
> > - unsigned int len;
> > + unsigned int len = 0;
>
> It might be better to add a new label next_rx_no_prod_no_len and have
> the TPA code paths jump there instead.
>
> Andy, what do you think?
>

Yes, I think that would be a better fix. Making the TPA vs not-TPA as
explicit and intentional as possible seems like a good idea.

> > u8 *data_ptr, agg_bufs, cmp_type;
> > dma_addr_t dma_addr;
> > struct sk_buff *skb;
> > --
> > 2.15.1
> >

2018-01-16 10:23:23

by Colin King

Subject: Re: [PATCH][next] bnxt_en: ensure len is ininitialized to zero

On 12/01/18 22:38, Andy Gospodarek wrote:
> On Fri, Jan 12, 2018 at 10:11:17AM -0800, Michael Chan wrote:
>> On Fri, Jan 12, 2018 at 9:46 AM, Colin King <[email protected]> wrote:
>>> From: Colin Ian King <[email protected]>
>>>
>>> In the case where cmp_type == CMP_TYPE_RX_L2_TPA_START_CMP the
>>> exit return path is via label next_rx_no_prod and cpr->rx_bytes
>>> is being updated by an uninitialized value from len. Fix this by
>>> initializing len to zero.
>>>
>>> Detected by CoverityScan, CID#1463807 ("Uninitialized scalar variable")
>>>
>>> Fixes: 6a8788f25625 ("bnxt_en: add support for software dynamic interrupt moderation")
>>> Signed-off-by: Colin Ian King <[email protected]>
>>> ---
>>> drivers/net/ethernet/broadcom/bnxt/bnxt.c | 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
>>> index cf6ebf1e324b..5b5c4f266f1b 100644
>>> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
>>> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
>>> @@ -1482,7 +1482,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_napi *bnapi, u32 *raw_cons,
>>> u32 tmp_raw_cons = *raw_cons;
>>> u16 cfa_code, cons, prod, cp_cons = RING_CMP(tmp_raw_cons);
>>> struct bnxt_sw_rx_bd *rx_buf;
>>> - unsigned int len;
>>> + unsigned int len = 0;
>>
>> It might be better to add a new label next_rx_no_prod_no_len and have
>> the TPA code paths jump there instead.
>>
>> Andy, what do you think?
>>
>
> Yes, I think that would be a better fix. Making the TPA vs not-TPA as
> explicit and intentional as possible seems like a good idea.

OK, new patch sent.
>
>>> u8 *data_ptr, agg_bufs, cmp_type;
>>> dma_addr_t dma_addr;
>>> struct sk_buff *skb;
>>> --
>>> 2.15.1
>>>
> --
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