On Tue, Jun 23, 2020 at 02:33:56PM +0200, Daniel Gröber wrote:
> Currently the BUFFER_SIZE macro doesn't take negative 'ret' values into
> account. A negative return should just be passed through to the caller,
> snprintf will already have set 'errno' properly.
>
> Signed-off-by: Daniel Gröber <dxld@xxxxxxxxxxxxx>
> ---
> include/internal/internal.h | 2 ++
> src/conntrack/api.c | 6 +++---
> src/conntrack/snprintf.c | 3 +++
> src/expect/snprintf.c | 3 +++
> 4 files changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/include/internal/internal.h b/include/internal/internal.h
> index bb44e12..859724b 100644
> --- a/include/internal/internal.h
> +++ b/include/internal/internal.h
> @@ -41,6 +41,8 @@
> #endif
>
> #define BUFFER_SIZE(ret, size, len, offset) \
> + if(ret < 0) \
if (ret < 0)
^
missing space
> + return -1; \
> size += ret; \
> if (ret > len) \
> ret = len; \
> diff --git a/src/conntrack/api.c b/src/conntrack/api.c
> index ffa5216..78d7d61 100644
> --- a/src/conntrack/api.c
> +++ b/src/conntrack/api.c
> @@ -1099,9 +1099,9 @@ int nfct_catch(struct nfct_handle *h)
> * print the message just after you receive the destroy event. If you want
> * more accurate timestamping, use NFCT_OF_TIMESTAMP.
> *
> - * This function returns the size of the information that _would_ have been
> - * written to the buffer, even if there was no room for it. Thus, the
> - * behaviour is similar to snprintf.
> + * On error, -1 is returned and errno is set appropiately. Otherwise the
> + * size of what _would_ be written is returned, even if the size of the
> + * buffer is insufficient. This behaviour is similar to snprintf.
> */
> int nfct_snprintf(char *buf,
> unsigned int size,
> diff --git a/src/conntrack/snprintf.c b/src/conntrack/snprintf.c
> index 17ad885..a87c0c9 100644
> --- a/src/conntrack/snprintf.c
> +++ b/src/conntrack/snprintf.c
> @@ -85,6 +85,9 @@ int __snprintf_conntrack(char *buf,
> return -1;
> }
>
> + if(size < 0)
^^^^^^^^
I can see spaces here as indentations.
> + return size;
> +
> /* NULL terminated string */
> buf[size+1 > len ? len-1 : size] = '\0';
>
> diff --git a/src/expect/snprintf.c b/src/expect/snprintf.c
> index 3a104b5..b28ac62 100644
> --- a/src/expect/snprintf.c
> +++ b/src/expect/snprintf.c
> @@ -30,6 +30,9 @@ int __snprintf_expect(char *buf,
> return -1;
> }
>
> + if(size < 0)
> + return size;
> +
> /* NULL terminated string */
> buf[size+1 > len ? len-1 : size] = '\0';
>
> --
> 2.20.1
>
