wifi: mt76: fix clang-specific fortify warnings
authorDmitry Antipov <dmantipov@yandex.ru>
Tue, 29 Aug 2023 09:43:49 +0000 (12:43 +0300)
committerFelix Fietkau <nbd@nbd.name>
Sat, 30 Sep 2023 18:03:04 +0000 (20:03 +0200)
commit03f0e11da7fb26db4f27e6b83a223512db9f7ca5
treeb934dd9e7513bff0f8731360f9baa6288b8a77b3
parentfce9c967820a72f600abbf061d7077861685a14d
wifi: mt76: fix clang-specific fortify warnings

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>
drivers/net/wireless/mediatek/mt76/mt7915/main.c
drivers/net/wireless/mediatek/mt76/mt792x_core.c
drivers/net/wireless/mediatek/mt76/mt7996/main.c