From 53f30b41ec252d9973719b349a644477e72e1a09 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Thu, 20 Jan 2011 01:20:36 +0100 Subject: [PATCH 1/3] ifplugd: eliminate aliasing warnings Signed-off-by: Denys Vlasenko --- networking/ifplugd.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/networking/ifplugd.c b/networking/ifplugd.c index 58f56dbf1..3b59a63ff 100644 --- a/networking/ifplugd.c +++ b/networking/ifplugd.c @@ -131,18 +131,20 @@ static int network_ioctl(int request, void* data, const char *errmsg) static smallint detect_link_mii(void) { - struct ifreq ifreq; - struct mii_ioctl_data *mii = (void *)&ifreq.ifr_data; + /* char buffer instead of bona-fide struct avoids aliasing warning */ + char buf[sizeof(struct ifreq)]; + struct ifreq *ifreq = (void *)buf; + struct mii_ioctl_data *mii = (void *)&ifreq->ifr_data; - set_ifreq_to_ifname(&ifreq); + set_ifreq_to_ifname(ifreq); - if (network_ioctl(SIOCGMIIPHY, &ifreq, "SIOCGMIIPHY") < 0) { + if (network_ioctl(SIOCGMIIPHY, ifreq, "SIOCGMIIPHY") < 0) { return IFSTATUS_ERR; } mii->reg_num = 1; - if (network_ioctl(SIOCGMIIREG, &ifreq, "SIOCGMIIREG") < 0) { + if (network_ioctl(SIOCGMIIREG, ifreq, "SIOCGMIIREG") < 0) { return IFSTATUS_ERR; } @@ -151,18 +153,20 @@ static smallint detect_link_mii(void) static smallint detect_link_priv(void) { - struct ifreq ifreq; - struct mii_ioctl_data *mii = (void *)&ifreq.ifr_data; + /* char buffer instead of bona-fide struct avoids aliasing warning */ + char buf[sizeof(struct ifreq)]; + struct ifreq *ifreq = (void *)buf; + struct mii_ioctl_data *mii = (void *)&ifreq->ifr_data; - set_ifreq_to_ifname(&ifreq); + set_ifreq_to_ifname(ifreq); - if (network_ioctl(SIOCDEVPRIVATE, &ifreq, "SIOCDEVPRIVATE") < 0) { + if (network_ioctl(SIOCDEVPRIVATE, ifreq, "SIOCDEVPRIVATE") < 0) { return IFSTATUS_ERR; } mii->reg_num = 1; - if (network_ioctl(SIOCDEVPRIVATE+1, &ifreq, "SIOCDEVPRIVATE+1") < 0) { + if (network_ioctl(SIOCDEVPRIVATE+1, ifreq, "SIOCDEVPRIVATE+1") < 0) { return IFSTATUS_ERR; } From b3b6c8bdf23d30c57d92458f1aac93ce84bf81a7 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Thu, 20 Jan 2011 11:29:00 +0100 Subject: [PATCH 2/3] eliminate aliasing warning in networking/route.c Signed-off-by: Denys Vlasenko --- networking/ifplugd.c | 6 ++-- networking/route.c | 71 +++++++++++++++++++++++--------------------- 2 files changed, 41 insertions(+), 36 deletions(-) diff --git a/networking/ifplugd.c b/networking/ifplugd.c index 3b59a63ff..8dd0a5bd8 100644 --- a/networking/ifplugd.c +++ b/networking/ifplugd.c @@ -133,7 +133,8 @@ static smallint detect_link_mii(void) { /* char buffer instead of bona-fide struct avoids aliasing warning */ char buf[sizeof(struct ifreq)]; - struct ifreq *ifreq = (void *)buf; + struct ifreq *const ifreq = (void *)buf; + struct mii_ioctl_data *mii = (void *)&ifreq->ifr_data; set_ifreq_to_ifname(ifreq); @@ -155,7 +156,8 @@ static smallint detect_link_priv(void) { /* char buffer instead of bona-fide struct avoids aliasing warning */ char buf[sizeof(struct ifreq)]; - struct ifreq *ifreq = (void *)buf; + struct ifreq *const ifreq = (void *)buf; + struct mii_ioctl_data *mii = (void *)&ifreq->ifr_data; set_ifreq_to_ifname(ifreq); diff --git a/networking/route.c b/networking/route.c index 98567aaee..b7d08dd63 100644 --- a/networking/route.c +++ b/networking/route.c @@ -153,7 +153,10 @@ static int kw_lookup(const char *kwtbl, char ***pargs) static NOINLINE void INET_setroute(int action, char **args) { - struct rtentry rt; + /* char buffer instead of bona-fide struct avoids aliasing warning */ + char rt_buf[sizeof(struct rtentry)]; + struct rtentry *const rt = (void *)rt_buf; + const char *netmask = NULL; int skfd, isnet, xflag; @@ -166,7 +169,7 @@ static NOINLINE void INET_setroute(int action, char **args) } /* Clean out the RTREQ structure. */ - memset(&rt, 0, sizeof(rt)); + memset(rt, 0, sizeof(*rt)); { const char *target = *args++; @@ -178,17 +181,17 @@ static NOINLINE void INET_setroute(int action, char **args) int prefix_len; prefix_len = xatoul_range(prefix+1, 0, 32); - mask_in_addr(rt) = htonl( ~(0xffffffffUL >> prefix_len)); + mask_in_addr(*rt) = htonl( ~(0xffffffffUL >> prefix_len)); *prefix = '\0'; #if HAVE_NEW_ADDRT - rt.rt_genmask.sa_family = AF_INET; + rt->rt_genmask.sa_family = AF_INET; #endif } else { /* Default netmask. */ netmask = "default"; } /* Prefer hostname lookup is -host flag (xflag==1) was given. */ - isnet = INET_resolve(target, (struct sockaddr_in *) &rt.rt_dst, + isnet = INET_resolve(target, (struct sockaddr_in *) &rt->rt_dst, (xflag & HOST_FLAG)); if (isnet < 0) { bb_error_msg_and_die("resolving %s", target); @@ -204,20 +207,20 @@ static NOINLINE void INET_setroute(int action, char **args) } /* Fill in the other fields. */ - rt.rt_flags = ((isnet) ? RTF_UP : (RTF_UP | RTF_HOST)); + rt->rt_flags = ((isnet) ? RTF_UP : (RTF_UP | RTF_HOST)); while (*args) { int k = kw_lookup(tbl_ipvx, &args); const char *args_m1 = args[-1]; if (k & KW_IPVx_FLAG_ONLY) { - rt.rt_flags |= flags_ipvx[k & 3]; + rt->rt_flags |= flags_ipvx[k & 3]; continue; } #if HAVE_NEW_ADDRT if (k == KW_IPVx_METRIC) { - rt.rt_metric = xatoul(args_m1) + 1; + rt->rt_metric = xatoul(args_m1) + 1; continue; } #endif @@ -225,7 +228,7 @@ static NOINLINE void INET_setroute(int action, char **args) if (k == KW_IPVx_NETMASK) { struct sockaddr mask; - if (mask_in_addr(rt)) { + if (mask_in_addr(*rt)) { bb_show_usage(); } @@ -234,18 +237,18 @@ static NOINLINE void INET_setroute(int action, char **args) if (isnet < 0) { bb_error_msg_and_die("resolving %s", netmask); } - rt.rt_genmask = full_mask(mask); + rt->rt_genmask = full_mask(mask); continue; } if (k == KW_IPVx_GATEWAY) { - if (rt.rt_flags & RTF_GATEWAY) { + if (rt->rt_flags & RTF_GATEWAY) { bb_show_usage(); } isnet = INET_resolve(args_m1, - (struct sockaddr_in *) &rt.rt_gateway, 1); - rt.rt_flags |= RTF_GATEWAY; + (struct sockaddr_in *) &rt->rt_gateway, 1); + rt->rt_flags |= RTF_GATEWAY; if (isnet) { if (isnet < 0) { @@ -257,24 +260,24 @@ static NOINLINE void INET_setroute(int action, char **args) } if (k == KW_IPVx_MSS) { /* Check valid MSS bounds. */ - rt.rt_flags |= RTF_MSS; - rt.rt_mss = xatoul_range(args_m1, 64, 32768); + rt->rt_flags |= RTF_MSS; + rt->rt_mss = xatoul_range(args_m1, 64, 32768); continue; } if (k == KW_IPVx_WINDOW) { /* Check valid window bounds. */ - rt.rt_flags |= RTF_WINDOW; - rt.rt_window = xatoul_range(args_m1, 128, INT_MAX); + rt->rt_flags |= RTF_WINDOW; + rt->rt_window = xatoul_range(args_m1, 128, INT_MAX); continue; } #ifdef RTF_IRTT if (k == KW_IPVx_IRTT) { - rt.rt_flags |= RTF_IRTT; - rt.rt_irtt = xatoul(args_m1); - rt.rt_irtt *= (sysconf(_SC_CLK_TCK) / 100); /* FIXME */ + rt->rt_flags |= RTF_IRTT; + rt->rt_irtt = xatoul(args_m1); + rt->rt_irtt *= (sysconf(_SC_CLK_TCK) / 100); /* FIXME */ #if 0 /* FIXME: do we need to check anything of this? */ - if (rt.rt_irtt < 1 || rt.rt_irtt > (120 * HZ)) { + if (rt->rt_irtt < 1 || rt->rt_irtt > (120 * HZ)) { bb_error_msg_and_die("bad irtt"); } #endif @@ -284,9 +287,9 @@ static NOINLINE void INET_setroute(int action, char **args) /* Device is special in that it can be the last arg specified * and doesn't requre the dev/device keyword in that case. */ - if (!rt.rt_dev && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) { + if (!rt->rt_dev && ((k == KW_IPVx_DEVICE) || (!k && !*++args))) { /* Don't use args_m1 here since args may have changed! */ - rt.rt_dev = args[-1]; + rt->rt_dev = args[-1]; continue; } @@ -295,41 +298,41 @@ static NOINLINE void INET_setroute(int action, char **args) } #ifdef RTF_REJECT - if ((rt.rt_flags & RTF_REJECT) && !rt.rt_dev) { - rt.rt_dev = (char*)"lo"; + if ((rt->rt_flags & RTF_REJECT) && !rt->rt_dev) { + rt->rt_dev = (char*)"lo"; } #endif /* sanity checks.. */ - if (mask_in_addr(rt)) { - uint32_t mask = mask_in_addr(rt); + if (mask_in_addr(*rt)) { + uint32_t mask = mask_in_addr(*rt); mask = ~ntohl(mask); - if ((rt.rt_flags & RTF_HOST) && mask != 0xffffffff) { + if ((rt->rt_flags & RTF_HOST) && mask != 0xffffffff) { bb_error_msg_and_die("netmask %.8x and host route conflict", (unsigned int) mask); } if (mask & (mask + 1)) { bb_error_msg_and_die("bogus netmask %s", netmask); } - mask = ((struct sockaddr_in *) &rt.rt_dst)->sin_addr.s_addr; - if (mask & ~(uint32_t)mask_in_addr(rt)) { + mask = ((struct sockaddr_in *) &rt->rt_dst)->sin_addr.s_addr; + if (mask & ~(uint32_t)mask_in_addr(*rt)) { bb_error_msg_and_die("netmask and route address conflict"); } } /* Fill out netmask if still unset */ - if ((action == RTACTION_ADD) && (rt.rt_flags & RTF_HOST)) { - mask_in_addr(rt) = 0xffffffff; + if ((action == RTACTION_ADD) && (rt->rt_flags & RTF_HOST)) { + mask_in_addr(*rt) = 0xffffffff; } /* Create a socket to the INET kernel. */ skfd = xsocket(AF_INET, SOCK_DGRAM, 0); if (action == RTACTION_ADD) - xioctl(skfd, SIOCADDRT, &rt); + xioctl(skfd, SIOCADDRT, rt); else - xioctl(skfd, SIOCDELRT, &rt); + xioctl(skfd, SIOCDELRT, rt); if (ENABLE_FEATURE_CLEAN_UP) close(skfd); } From dd169e84683aa7be3604d491f1c34ab657973365 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Thu, 20 Jan 2011 12:13:23 +0100 Subject: [PATCH 3/3] eliminate aliasing warnings in traceroute.c and udhcp/socket.c Signed-off-by: Denys Vlasenko --- networking/traceroute.c | 3 ++- networking/udhcp/socket.c | 25 ++++++++++++++----------- 2 files changed, 16 insertions(+), 12 deletions(-) diff --git a/networking/traceroute.c b/networking/traceroute.c index c18fba8d0..82bb0118c 100644 --- a/networking/traceroute.c +++ b/networking/traceroute.c @@ -751,7 +751,8 @@ print(int read_len, const struct sockaddr *from, const struct sockaddr *to) } else #endif { - read_len -= ((struct ip*)recv_pkt)->ip_hl << 2; + struct ip *ip4packet = (struct ip*)recv_pkt; + read_len -= ip4packet->ip_hl << 2; } printf(" %d bytes to %s", read_len, ina); free(ina); diff --git a/networking/udhcp/socket.c b/networking/udhcp/socket.c index 0ed7ad1c6..39f1cec54 100644 --- a/networking/udhcp/socket.c +++ b/networking/udhcp/socket.c @@ -36,42 +36,45 @@ int FAST_FUNC udhcp_read_interface(const char *interface, int *ifindex, uint32_t *nip, uint8_t *mac) { + /* char buffer instead of bona-fide struct avoids aliasing warning */ + char ifr_buf[sizeof(struct ifreq)]; + struct ifreq *const ifr = (void *)ifr_buf; + int fd; - struct ifreq ifr; struct sockaddr_in *our_ip; - memset(&ifr, 0, sizeof(ifr)); + memset(ifr, 0, sizeof(*ifr)); fd = xsocket(AF_INET, SOCK_RAW, IPPROTO_RAW); - ifr.ifr_addr.sa_family = AF_INET; - strncpy_IFNAMSIZ(ifr.ifr_name, interface); + ifr->ifr_addr.sa_family = AF_INET; + strncpy_IFNAMSIZ(ifr->ifr_name, interface); if (nip) { - if (ioctl_or_perror(fd, SIOCGIFADDR, &ifr, + if (ioctl_or_perror(fd, SIOCGIFADDR, ifr, "is interface %s up and configured?", interface) ) { close(fd); return -1; } - our_ip = (struct sockaddr_in *) &ifr.ifr_addr; + our_ip = (struct sockaddr_in *) &ifr->ifr_addr; *nip = our_ip->sin_addr.s_addr; log1("IP %s", inet_ntoa(our_ip->sin_addr)); } if (ifindex) { - if (ioctl_or_warn(fd, SIOCGIFINDEX, &ifr) != 0) { + if (ioctl_or_warn(fd, SIOCGIFINDEX, ifr) != 0) { close(fd); return -1; } - log1("Adapter index %d", ifr.ifr_ifindex); - *ifindex = ifr.ifr_ifindex; + log1("Adapter index %d", ifr->ifr_ifindex); + *ifindex = ifr->ifr_ifindex; } if (mac) { - if (ioctl_or_warn(fd, SIOCGIFHWADDR, &ifr) != 0) { + if (ioctl_or_warn(fd, SIOCGIFHWADDR, ifr) != 0) { close(fd); return -1; } - memcpy(mac, ifr.ifr_hwaddr.sa_data, 6); + memcpy(mac, ifr->ifr_hwaddr.sa_data, 6); log1("MAC %02x:%02x:%02x:%02x:%02x:%02x", mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]); }