Re: [nfs-utils PATCH] fsidd: replace assertions with explicit malformed-input handling

[Steve Dickson <steved@redhat.com>]

On 9/3/26 1:48 PM, Scott Mayhew wrote:
> fsidd relies on assert() to ensure that an argument is present after the
> command prefix while parsing commands received over the local socket.
> Malformed input can cause fsidd to abort.  Replace the assertions with
> explicit malformed-input handling and return an error to the client.
> 
> Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Committed... (tag: nfs-utils-2-9-3-rc4)

steved.
> ---
>   support/reexport/fsidd.c | 19 +++++++++++++++----
>   1 file changed, 15 insertions(+), 4 deletions(-)
> 
> diff --git a/support/reexport/fsidd.c b/support/reexport/fsidd.c
> index 51750ea3..f5c397aa 100644
> --- a/support/reexport/fsidd.c
> +++ b/support/reexport/fsidd.c
> @@ -48,7 +48,11 @@ static void client_cb(evutil_socket_t cl, short ev, void *d)
>   		char *answer = NULL;
>   		bool found;
>   
> -		assert(req_path < buf + n );
> +		if (req_path >= buf + n) {
> +			char answer[] = "- Command failed: Bad input";
> +			(void)send(cl, answer, strlen(answer), 0);
> +			return;
> +		}
>   
>   		printf("client asks for %s\n", req_path);
>   
> @@ -70,8 +74,11 @@ static void client_cb(evutil_socket_t cl, short ev, void *d)
>   		char *answer = NULL;
>   		bool found;
>   
> -		assert(req_path < buf + n );
> -
> +		if (req_path >= buf + n) {
> +			char answer[] = "- Command failed: Bad input";
> +			(void)send(cl, answer, strlen(answer), 0);
> +			return;
> +		}
>   
>   		if (dbbackend->fsidnum_by_path(req_path, &fsidnum, true, &found)) {
>   			if (found) {
> @@ -94,7 +101,11 @@ static void client_cb(evutil_socket_t cl, short ev, void *d)
>   		uint32_t fsidnum;
>   		bool found;
>   
> -		assert(req_fsidnum < buf + n );
> +		if (req_fsidnum >= buf + n) {
> +			char answer[] = "- Command failed: Bad input";
> +			(void)send(cl, answer, strlen(answer), 0);
> +			return;
> +		}
>   
>   		errno = 0;
>   		fsidnum = strtoul(req_fsidnum, &endp, 10);