From: Ye Guojin <[email protected]>
This was found by coccicheck:
./drivers/net/wireless/intel/iwlwifi/fw/rs.c, 147, 10-21, WARNING
Unsigned expression compared with zero legacy_rate < 0
Reported-by: Zeal Robot <[email protected]>
Signed-off-by: Ye Guojin <[email protected]>
---
drivers/net/wireless/intel/iwlwifi/fw/api/rs.h | 2 +-
drivers/net/wireless/intel/iwlwifi/fw/rs.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/net/wireless/intel/iwlwifi/fw/api/rs.h b/drivers/net/wireless/intel/iwlwifi/fw/api/rs.h
index a09081d7ed45..7794cd6d289d 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/api/rs.h
+++ b/drivers/net/wireless/intel/iwlwifi/fw/api/rs.h
@@ -710,7 +710,7 @@ struct iwl_lq_cmd {
u8 iwl_fw_rate_idx_to_plcp(int idx);
u32 iwl_new_rate_from_v1(u32 rate_v1);
-u32 iwl_legacy_rate_to_fw_idx(u32 rate_n_flags);
+int iwl_legacy_rate_to_fw_idx(u32 rate_n_flags);
const struct iwl_rate_mcs_info *iwl_rate_mcs(int idx);
const char *iwl_rs_pretty_ant(u8 ant);
const char *iwl_rs_pretty_bw(int bw);
diff --git a/drivers/net/wireless/intel/iwlwifi/fw/rs.c b/drivers/net/wireless/intel/iwlwifi/fw/rs.c
index a21c3befd93b..3850881210e6 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/rs.c
+++ b/drivers/net/wireless/intel/iwlwifi/fw/rs.c
@@ -142,7 +142,7 @@ u32 iwl_new_rate_from_v1(u32 rate_v1)
}
/* if legacy format */
} else {
- u32 legacy_rate = iwl_legacy_rate_to_fw_idx(rate_v1);
+ int legacy_rate = iwl_legacy_rate_to_fw_idx(rate_v1);
WARN_ON(legacy_rate < 0);
rate_v2 |= legacy_rate;
@@ -172,7 +172,7 @@ u32 iwl_new_rate_from_v1(u32 rate_v1)
}
IWL_EXPORT_SYMBOL(iwl_new_rate_from_v1);
-u32 iwl_legacy_rate_to_fw_idx(u32 rate_n_flags)
+int iwl_legacy_rate_to_fw_idx(u32 rate_n_flags)
{
int rate = rate_n_flags & RATE_LEGACY_RATE_MSK_V1;
int idx;
--
2.25.1
On Wed, 2021-11-17 at 06:36 +0000, [email protected] wrote:
> From: Ye Guojin <[email protected]>
>
> This was found by coccicheck:
> ./drivers/net/wireless/intel/iwlwifi/fw/rs.c, 147, 10-21, WARNING
> Unsigned expression compared with zero legacy_rate < 0
[]
> diff --git a/drivers/net/wireless/intel/iwlwifi/fw/rs.c b/drivers/net/wireless/intel/iwlwifi/fw/rs.c
[]
> @@ -142,7 +142,7 @@ u32 iwl_new_rate_from_v1(u32 rate_v1)
> }
> /* if legacy format */
> } else {
> - u32 legacy_rate = iwl_legacy_rate_to_fw_idx(rate_v1);
> + int legacy_rate = iwl_legacy_rate_to_fw_idx(rate_v1);
>
> WARN_ON(legacy_rate < 0);
Why not just remove the WARN_ON instead?
On Tue, 2021-11-16 at 22:41 -0800, Joe Perches wrote:
> On Wed, 2021-11-17 at 06:36 +0000, [email protected] wrote:
> > From: Ye Guojin <[email protected]>
> >
> > This was found by coccicheck:
> > ./drivers/net/wireless/intel/iwlwifi/fw/rs.c, 147, 10-21, WARNING
> > Unsigned expression compared with zero legacy_rate < 0
> []
> > diff --git a/drivers/net/wireless/intel/iwlwifi/fw/rs.c b/drivers/net/wireless/intel/iwlwifi/fw/rs.c
> []
> > @@ -142,7 +142,7 @@ u32 iwl_new_rate_from_v1(u32 rate_v1)
> > }
> > /* if legacy format */
> > } else {
> > - u32 legacy_rate = iwl_legacy_rate_to_fw_idx(rate_v1);
> > + int legacy_rate = iwl_legacy_rate_to_fw_idx(rate_v1);
> >
> > WARN_ON(legacy_rate < 0);
>
> Why not just remove the WARN_ON instead?
>
Well, iwl_legacy_rate_to_fw_idx() _tries_ to return -1 if we can't find
the index.
But there are a few more wrong things in this implementation:
1. the iwl_legacy_rate_to_fw_idx() function is only called inside the
fw/rs.c file, so it should be static;
2. if we don't find the idx and return -1, we WARN but still use the
value, which will cause the rate_v2 to be set to 0xffffffff, which I'm
pretty sure is not the intention.
So, this should be fixed properly, rather than just changing the
function to return int.
--
Cheers,
Luca.