[DTrace-devel] [PATCH v2 2/7] cmd, libdtrace: fix potentially unsafe printf-like calls

[Eugene Loh]

How does v2 differ from the earlier patch?

On 12/6/22 17:17, Kris Van Hees via DTrace-devel wrote:
> GCC 12 flagged some calls to printf-style functions for using a dynamic
> string as format without arguments.  If the dymanic string somehow can
> be made to contain a substitution sequence (%<something>) this would be
> unsafe.
>
> Signed-off-by: Kris Van Hees<kris.van.hees at oracle.com>
> ---
>   cmd/dtrace.c          | 4 ++--
>   libdtrace/dt_printf.c | 2 +-
>   2 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/cmd/dtrace.c b/cmd/dtrace.c
> index 732150df..58325921 100644
> --- a/cmd/dtrace.c
> +++ b/cmd/dtrace.c
> @@ -521,7 +521,7 @@ prochandler(pid_t pid, const char *msg, void *arg)
>   static int
>   errhandler(const dtrace_errdata_t *data, void *arg)
>   {
> -	error(data->dteda_msg);
> +	error("%s", data->dteda_msg);
>   	return DTRACE_HANDLE_OK;
>   }
>   
> @@ -529,7 +529,7 @@ errhandler(const dtrace_errdata_t *data, void *arg)
>   static int
>   drophandler(const dtrace_dropdata_t *data, void *arg)
>   {
> -	error(data->dtdda_msg);
> +	error("%s", data->dtdda_msg);
>   	return DTRACE_HANDLE_OK;
>   }
>   
> diff --git a/libdtrace/dt_printf.c b/libdtrace/dt_printf.c
> index d060670a..6ee317e6 100644
> --- a/libdtrace/dt_printf.c
> +++ b/libdtrace/dt_printf.c
> @@ -1305,7 +1305,7 @@ dt_printf_format(dtrace_hdl_t *dtp, FILE *fp, const dt_pfargv_t *pfv,
>   			memcpy(tmp, pfd->pfd_prefix, pfd->pfd_preflen);
>   			tmp[pfd->pfd_preflen] = '\0';
>   
> -			if ((rval = dt_printf(dtp, fp, tmp)) < 0)
> +			if ((rval = dt_printf(dtp, fp, "%s", tmp)) < 0)
>   				return rval;
>   
>   			if (pfv->pfv_flags & DT_PRINTF_AGGREGATION) {
> -- 2.37.2 _______________________________________________ DTrace-devel 
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