wifi: mt76: fix clang-specific fortify warnings

[ Upstream commit 03f0e11da7fb26db4f27e6b83a223512db9f7ca5 ]

When compiling with clang 16.0.6 and CONFIG_FORTIFY_SOURCE=y, I've
noticed the following (somewhat confusing due to absence of an actual
source code location):

In file included from drivers/net/wireless/mediatek/mt76/mt792x_core.c:4:
In file included from ./include/linux/module.h:13:
In file included from ./include/linux/stat.h:19:
In file included from ./include/linux/time.h:60:
In file included from ./include/linux/time32.h:13:
In file included from ./include/linux/timex.h:67:
In file included from ./arch/x86/include/asm/timex.h:5:
In file included from ./arch/x86/include/asm/processor.h:23:
In file included from ./arch/x86/include/asm/msr.h:11:
In file included from ./arch/x86/include/asm/cpumask.h:5:
In file included from ./include/linux/cpumask.h:12:
In file included from ./include/linux/bitmap.h:11:
In file included from ./include/linux/string.h:254:
./include/linux/fortify-string.h:592:4: warning: call to '__read_overflow2_field'
declared with 'warning' attribute: detected read beyond size of field (2nd
parameter); maybe use struct_group()? [-Wattribute-warning]
                        __read_overflow2_field(q_size_field, size);

In file included from drivers/net/wireless/mediatek/mt76/mt7915/main.c:4:
In file included from ./include/linux/etherdevice.h:20:
In file included from ./include/linux/if_ether.h:19:
In file included from ./include/linux/skbuff.h:15:
In file included from ./include/linux/time.h:60:
In file included from ./include/linux/time32.h:13:
In file included from ./include/linux/timex.h:67:
In file included from ./arch/x86/include/asm/timex.h:5:
In file included from ./arch/x86/include/asm/processor.h:23:
In file included from ./arch/x86/include/asm/msr.h:11:
In file included from ./arch/x86/include/asm/cpumask.h:5:
In file included from ./include/linux/cpumask.h:12:
In file included from ./include/linux/bitmap.h:11:
In file included from ./include/linux/string.h:254:
./include/linux/fortify-string.h:592:4: warning: call to '__read_overflow2_field'
declared with 'warning' attribute: detected read beyond size of field (2nd
parameter); maybe use struct_group()? [-Wattribute-warning]
                        __read_overflow2_field(q_size_field, size);

In file included from drivers/net/wireless/mediatek/mt76/mt7996/main.c:6:
In file included from drivers/net/wireless/mediatek/mt76/mt7996/mt7996.h:9:
In file included from ./include/linux/interrupt.h:8:
In file included from ./include/linux/cpumask.h:12:
In file included from ./include/linux/bitmap.h:11:
In file included from ./include/linux/string.h:254:
./include/linux/fortify-string.h:592:4: warning: call to '__read_overflow2_field'
declared with 'warning' attribute: detected read beyond size of field (2nd
parameter); maybe use struct_group()? [-Wattribute-warning]
                        __read_overflow2_field(q_size_field, size);

The compiler actually complains on 'mt7915_get_et_strings()',
'mt792x_get_et_strings()' and 'mt7996_get_et_strings()' due to the same
reason: fortification logic inteprets call to 'memcpy()' as an attempt
to copy the whole array from its first member and so issues an overread
warning. These warnings may be silenced by passing an address of the whole
array and not the first member to 'memcpy()'.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/main.c b/drivers/net/wireless/mediatek/mt76/mt7915/main.c
index d06c25d..d85105a 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7915/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/main.c
@@ -1388,7 +1388,7 @@ void mt7915_get_et_strings(struct ieee80211_hw *hw,
        if (sset != ETH_SS_STATS)
                return;
 
-       memcpy(data, *mt7915_gstrings_stats, sizeof(mt7915_gstrings_stats));
+       memcpy(data, mt7915_gstrings_stats, sizeof(mt7915_gstrings_stats));
        data += sizeof(mt7915_gstrings_stats);
        page_pool_ethtool_stats_get_strings(data);
 }

diff --git a/drivers/net/wireless/mediatek/mt76/mt792x_core.c b/drivers/net/wireless/mediatek/mt76/mt792x_core.c
index ec98450..f111c47 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt792x_core.c
+++ b/drivers/net/wireless/mediatek/mt76/mt792x_core.c
@@ -358,7 +358,7 @@ void mt792x_get_et_strings(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
        if (sset != ETH_SS_STATS)
                return;
 
-       memcpy(data, *mt792x_gstrings_stats, sizeof(mt792x_gstrings_stats));
+       memcpy(data, mt792x_gstrings_stats, sizeof(mt792x_gstrings_stats));
 
        data += sizeof(mt792x_gstrings_stats);
        page_pool_ethtool_stats_get_strings(data);

diff --git a/drivers/net/wireless/mediatek/mt76/mt7996/main.c b/drivers/net/wireless/mediatek/mt76/mt7996/main.c
index 6e0f0c1..620880e 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7996/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7996/main.c
@@ -1198,7 +1198,7 @@ void mt7996_get_et_strings(struct ieee80211_hw *hw,
                           u32 sset, u8 *data)
 {
        if (sset == ETH_SS_STATS)
-               memcpy(data, *mt7996_gstrings_stats,
+               memcpy(data, mt7996_gstrings_stats,
                       sizeof(mt7996_gstrings_stats));
 }