readdir: Replace one-element arrays with flexible-array members
One-element arrays are deprecated, and we are replacing them with flexible
array members instead. So, replace one-element arrays with flexible-array
members in multiple structures.
Address the following -Wstringop-overflow warnings seen when built
m68k architecture with m5307c3_defconfig configuration:
In function '__put_user_fn',
inlined from 'fillonedir' at fs/readdir.c:170:2:
include/asm-generic/uaccess.h:49:35: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
49 | *(u8 __force *)to = *(u8 *)from;
| ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~
fs/readdir.c: In function 'fillonedir':
fs/readdir.c:134:25: note: at offset 1 into destination object 'd_name' of size 1
134 | char d_name[1];
| ^~~~~~
In function '__put_user_fn',
inlined from 'filldir' at fs/readdir.c:257:2:
include/asm-generic/uaccess.h:49:35: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
49 | *(u8 __force *)to = *(u8 *)from;
| ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~
fs/readdir.c: In function 'filldir':
fs/readdir.c:211:25: note: at offset 1 into destination object 'd_name' of size 1
211 | char d_name[1];
| ^~~~~~
This helps with the ongoing efforts to globally enable
-Wstringop-overflow.
This results in no differences in binary output.
Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/312
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Message-Id: <ZJHiPJkNKwxkKz1c@work>
Signed-off-by: Christian Brauner <brauner@kernel.org>