n-dhcp4/packet: avoid compiler warning in n_dhcp4_c_socket_packet_recv()

gcc-10.2.1-1.fc32 with optimizations and LTO enabled can think that "len"
is uninitialized. Let packet_recv_udp() always set the length.

  ../src/n-dhcp4-socket.c: In function ‘n_dhcp4_c_socket_packet_recv.constprop’:
  ../src/n-dhcp4-incoming.c:210:29: error: ‘len’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
    210 |         incoming->n_message = n_raw;
        |                             ^
  ../src/n-dhcp4-socket.c:558:16: note: ‘len’ was declared here
    558 |         size_t len;
        |                ^

142eedcfc3
This commit is contained in:
Thomas Haller 2020-08-14 14:19:44 +02:00
parent d2c58bc64d
commit 08318a0bac
No known key found for this signature in database
GPG key ID: 29C2366E4DFC5728

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@ -293,6 +293,8 @@ int packet_recvfrom_udp(int sockfd,
ssize_t pktlen;
size_t hdrlen;
*n_transmittedp = 0;
/* Peek packet to obtain the real IP header length */
pktlen = recv(sockfd, &ip_hdr.hdr, sizeof(ip_hdr.hdr), MSG_PEEK);
if (pktlen < 0)
@ -304,7 +306,6 @@ int packet_recvfrom_udp(int sockfd,
* discard it.
*/
recv(sockfd, NULL, 0, 0);
*n_transmittedp = 0;
return 0;
}
@ -313,7 +314,6 @@ int packet_recvfrom_udp(int sockfd,
* This is not an IPv4 packet, discard it.
*/
recv(sockfd, NULL, 0, 0);
*n_transmittedp = 0;
return 0;
}
@ -324,7 +324,6 @@ int packet_recvfrom_udp(int sockfd,
* header length, discard the packet.
*/
recv(sockfd, NULL, 0, 0);
*n_transmittedp = 0;
return 0;
}
@ -354,7 +353,6 @@ int packet_recvfrom_udp(int sockfd,
* provided too small a buffer. In both cases, we simply drop
* the packet.
*/
*n_transmittedp = 0;
return 0;
}
@ -366,14 +364,12 @@ int packet_recvfrom_udp(int sockfd,
* The packet is too small to even contain an entire UDP
* header, so discard it entirely.
*/
*n_transmittedp = 0;
return 0;
} else if ((size_t)pktlen < hdrlen + ntohs(udp_hdr.len)) {
/*
* The UDP header specified a longer length than the returned
* packet, so discard it entirely.
*/
*n_transmittedp = 0;
return 0;
}
@ -386,13 +382,10 @@ int packet_recvfrom_udp(int sockfd,
/* IP */
if (ip_hdr.hdr.protocol != IPPROTO_UDP) {
*n_transmittedp = 0;
return 0; /* not a UDP packet, discard it */
} else if (ip_hdr.hdr.frag_off & htons(IP_MF | IP_OFFMASK)) {
*n_transmittedp = 0;
return 0; /* fragmented packet, discard it */
} else if (checksum && packet_internet_checksum(ip_hdr.data, hdrlen)) {
*n_transmittedp = 0;
return 0; /* invalid checksum, discard it */
}
@ -411,7 +404,6 @@ int packet_recvfrom_udp(int sockfd,
buf,
pktlen,
udp_hdr.check)) {
*n_transmittedp = 0;
return 0;
}
}