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d3162773d

Denys Vlasenko

2018-02-11

SUCCESS Duration: 146s

Subject

arping: move packet buffer, sigset and struct ifreq to malloced "globals"

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

networking/arping.c +34 -41

networking/arping.c+34 -41

@@ -79,8 +79,11 @@ struct globals {
	unsigned received;
	unsigned brd_recv;
	unsigned req_recv;
+
+	struct ifreq ifr;
+	sigset_t sset;
+	unsigned char packet[4096];
	} FIX_ALIASING;
-	#define G ((struct globals)bb_common_bufsiz1)
	#define src (G.src )
	#define dst (G.dst )
	#define me (G.me )
@@ -95,8 +98,11 @@ struct globals {
	#define received (G.received )
	#define brd_recv (G.brd_recv )
	#define req_recv (G.req_recv )
+	//#define G ((struct globals)bb_common_bufsiz1)
+	#define G (*ptr_to_globals)
	#define INIT_G() do { \
-	setup_common_bufsiz(); \
+	/setup_common_bufsiz();/ \
+	SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
	count = -1; \
	} while (0)

@@ -183,15 +189,10 @@ static void recv_pack(unsigned char buf, int len, struct sockaddr_ll FROM)
	struct arphdr ah = (struct arphdr ) buf;
	unsigned char p = (unsigned char ) (ah + 1);
	struct in_addr src_ip, dst_ip;
+
	/* moves below assume in_addr is 4 bytes big, ensure that */
-	struct BUG_in_addr_must_be_4 {
-	char BUG_in_addr_must_be_4[
-	sizeof(struct in_addr) == 4 ? 1 : -1
-	];
-	char BUG_s_addr_must_be_4[
-	sizeof(src_ip.s_addr) == 4 ? 1 : -1
-	];
-	};
+	BUILD_BUG_ON(sizeof(struct in_addr) != 4);
+	BUILD_BUG_ON(sizeof(src_ip.s_addr) != 4);

	/* Filter out wild packets */
	if (FROM->sll_pkttype != PACKET_HOST
@@ -212,8 +213,10 @@ static void recv_pack(unsigned char buf, int len, struct sockaddr_ll FROM)
	if (ah->ar_pro != htons(ETH_P_IP)
	\|\| (ah->ar_pln != 4)
	\|\| (ah->ar_hln != me.sll_halen)
-	\|\| (len < (int)(sizeof(ah) + 2 (4 + ah->ar_hln))))
+	\|\| (len < (int)(sizeof(ah) + 2 (4 + ah->ar_hln)))
+	) {
	return;
+	}

	move_from_unaligned32(src_ip.s_addr, p + ah->ar_hln);
	move_from_unaligned32(dst_ip.s_addr, p + ah->ar_hln + 4 + ah->ar_hln);
@@ -292,7 +295,6 @@ int arping_main(int argc UNUSED_PARAM, char **argv)
	const char *device = "eth0";
	char *source = NULL;
	char *target;
-	unsigned char *packet;
	char *err_str;

	INIT_G();
@@ -316,27 +318,21 @@ int arping_main(int argc UNUSED_PARAM, char **argv)
	err_str = xasprintf("interface %s %%s", device);
	xfunc_error_retval = 2;

-	{
-	struct ifreq ifr;
-
-	memset(&ifr, 0, sizeof(ifr));
-	strncpy_IFNAMSIZ(ifr.ifr_name, device);
-	/* We use ifr.ifr_name in error msg so that problem
-	* with truncated name will be visible */
-	ioctl_or_perror_and_die(sock_fd, SIOCGIFINDEX, &ifr, err_str, "not found");
-	me.sll_ifindex = ifr.ifr_ifindex;
+	/memset(&G.ifr, 0, sizeof(G.ifr)); - zeroed by INIT_G /
+	strncpy_IFNAMSIZ(G.ifr.ifr_name, device);
+	ioctl_or_perror_and_die(sock_fd, SIOCGIFINDEX, &G.ifr, err_str, "not found");
+	me.sll_ifindex = G.ifr.ifr_ifindex;

-	xioctl(sock_fd, SIOCGIFFLAGS, (char *) &ifr);
+	xioctl(sock_fd, SIOCGIFFLAGS, (char *) &G.ifr);

-	if (!(ifr.ifr_flags & IFF_UP)) {
-	bb_error_msg_and_die(err_str, "is down");
-	}
-	if (ifr.ifr_flags & (IFF_NOARP \| IFF_LOOPBACK)) {
-	bb_error_msg(err_str, "is not ARPable");
-	BUILD_BUG_ON(DAD != 2);
-	/* exit 0 if DAD, else exit 2 */
-	return (~option_mask32 & DAD);
-	}
+	if (!(G.ifr.ifr_flags & IFF_UP)) {
+	bb_error_msg_and_die(err_str, "is down");
+	}
+	if (G.ifr.ifr_flags & (IFF_NOARP \| IFF_LOOPBACK)) {
+	bb_error_msg(err_str, "is not ARPable");
+	BUILD_BUG_ON(DAD != 2);
+	/* exit 0 if DAD, else exit 2 */
+	return (~option_mask32 & DAD);
	}

	/* if (!inet_aton(target, &dst)) - not needed */ {
@@ -413,8 +409,9 @@ int arping_main(int argc UNUSED_PARAM, char **argv)
	printf(" from %s %s\n", inet_ntoa(src), device);
	}

-	packet = xmalloc(4096);
-
+	/sigemptyset(&G.sset); - zeroed by INIT_G /
+	sigaddset(&G.sset, SIGALRM);
+	sigaddset(&G.sset, SIGINT);
	signal_SA_RESTART_empty_mask(SIGINT, (void (*)(int))finish);
	signal_SA_RESTART_empty_mask(SIGALRM, (void (*)(int))catcher);

@@ -422,28 +419,24 @@ int arping_main(int argc UNUSED_PARAM, char **argv)
	catcher();

	while (1) {
-	sigset_t sset;
	struct sockaddr_ll from;
	socklen_t alen = sizeof(from);
	int cc;

-	sigemptyset(&sset);
-	sigaddset(&sset, SIGALRM);
-	sigaddset(&sset, SIGINT);
	/* Unblock SIGALRM so that the previously called alarm()
	* can prevent recvfrom from blocking forever in case the
	* inherited procmask is blocking SIGALRM.
	*/
-	sigprocmask(SIG_UNBLOCK, &sset, NULL);
+	sigprocmask(SIG_UNBLOCK, &G.sset, NULL);

-	cc = recvfrom(sock_fd, packet, 4096, 0, (struct sockaddr *) &from, &alen);
+	cc = recvfrom(sock_fd, G.packet, sizeof(G.packet), 0, (struct sockaddr *) &from, &alen);

	/* Don't allow SIGALRMs while we process the reply */
-	sigprocmask(SIG_BLOCK, &sset, NULL);
+	sigprocmask(SIG_BLOCK, &G.sset, NULL);
	if (cc < 0) {
	bb_perror_msg("recvfrom");
	continue;
	}
-	recv_pack(packet, cc, &from);
+	recv_pack(G.packet, cc, &from);
	}
	}