On Tue 09-01-18 16:58:39, Xiongfeng Wang wrote:
> From: Xiongfeng Wang <xiongfeng.wang@xxxxxxxxxx>
>
> gcc-8 reports
>
> fs/ext4/super.c: In function '__save_error_info.isra.6':
> ./include/linux/string.h:245:9: warning: '__builtin_strncpy' specified
> bound 32 equals destination size [-Wstringop-truncation]
>
> We need to use strlcpy() to make sure the dest string is nul-terminated.
>
> Signed-off-by: Xiongfeng Wang <xiongfeng.wang@xxxxxxxxxx>
Please have a look how s_last_error_func is used. If you do that, you'll
notice that we do take care to print only sizeof(s_last_error_func)
characters from the string or NUL-terminate it (in e2fsprogs). So your
patch just wastes one character for useless NUL-termination...
Honza
> ---
> fs/ext4/super.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 7c46693..051b988 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -323,11 +323,11 @@ static void __save_error_info(struct super_block *sb, const char *func,
> return;
> es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
> es->s_last_error_time = cpu_to_le32(get_seconds());
> - strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
> + strlcpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
> es->s_last_error_line = cpu_to_le32(line);
> if (!es->s_first_error_time) {
> es->s_first_error_time = es->s_last_error_time;
> - strncpy(es->s_first_error_func, func,
> + strlcpy(es->s_first_error_func, func,
> sizeof(es->s_first_error_func));
> es->s_first_error_line = cpu_to_le32(line);
> es->s_first_error_ino = es->s_last_error_ino;
> --
> 1.8.3.1
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
