On 12/04/2019 14:16, Daniel P. Berrangé wrote:
> In file included from /usr/include/string.h:494,
> from include/qemu/osdep.h:101,
> from linux-user/uname.c:20:
> In function ‘strncpy’,
> inlined from ‘sys_uname’ at linux-user/uname.c:94:3:
> /usr/include/bits/string_fortified.h:106:10: warning: ‘__builtin_strncpy’
> output may be truncated copying 64 bytes from a string of length 64
> [-Wstringop-truncation]
> 106 | return __builtin___strncpy_chk (__dest, __src, __len, __bos
> (__dest));
> |
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> We don't care where the NUL terminator in the original uname
> field was. It suffices to copy the entire original field and
> simply force a NUL terminator at the end of the new field.
>
> Signed-off-by: Daniel P. Berrangé <berra...@redhat.com>
> ---
> linux-user/uname.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/linux-user/uname.c b/linux-user/uname.c
> index 313b79dbad..3dff33effe 100644
> --- a/linux-user/uname.c
> +++ b/linux-user/uname.c
> @@ -73,7 +73,7 @@ const char *cpu_to_uname_machine(void *cpu_env)
> #define COPY_UTSNAME_FIELD(dest, src) \
> do { \
> /* __NEW_UTS_LEN doesn't include terminating null */ \
> - (void) strncpy((dest), (src), __NEW_UTS_LEN); \
> + memcpy((dest), (src), MIN(sizeof(src), __NEW_UTS_LEN)); \
If we use sizeof(), I think we should use it for both:
MIN(sizeof(dest), sizeof(src))
Thanks,
Laurent
