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fc9e10803

Denis Vlasenko

2008-05-26

FAILED Duration: 20s

Subject

udhcpc: shrink udhcpc: guard against zero lease time

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 →

include/platform.h +14 -1 networking/udhcp/dhcpc.c +22 -11 networking/udhcp/dhcpc.h +0 -9

include/platform.h+14 -1

@@ -135,7 +135,18 @@
	#define SWAP_LE64(x) (x)
	#endif

+	/* ---- Unaligned access ------------------------------------ */
+
+	/* parameter is supposed to be an uint32_t* ptr */
+	#if defined(i386) \|\| defined(__x86_64__) /* + other arches? */
+	#define get_unaligned_u32p(u32p) (*(u32p))
+	#else
+	/* performs reasonably well (gcc usually inlines memcpy here) */
+	#define get_unaligned_u32p(u32p) ({ uint32_t __t; memcpy(&__t, (u32p), 4); __t; })
+	#endif
+
	/* ---- Networking ------------------------------------------ */
+
	#ifndef __APPLE__
	# include <arpa/inet.h>
	# ifndef __socklen_t_defined
@@ -146,6 +157,7 @@ typedef int socklen_t;
	#endif

	/* ---- Compiler dependent settings ------------------------- */
+
	#if (defined __digital__ && defined __unix__) \|\| defined __APPLE__
	# undef HAVE_MNTENT_H
	# undef HAVE_SYS_STATFS_H
@@ -163,9 +175,10 @@ __extension__ typedef unsigned long long __u64;
	#endif

	/----- Kernel versioning ------------------------------------/
+
	#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))

-	/* ---- miscellaneous --------------------------------------- */
+	/* ---- Miscellaneous --------------------------------------- */

	#if defined(__GNU_LIBRARY__) && __GNU_LIBRARY__ < 5 && \
	!defined(__dietlibc__) && \

networking/udhcp/dhcpc.c+22 -11

@@ -18,9 +18,6 @@
	#include "options.h"


-	static int timeout; /* = 0. Must be signed */
-	static uint32_t requested_ip; /* = 0 */
-	static uint32_t server_addr;
	static int sockfd = -1;

	#define LISTEN_NONE 0
@@ -28,6 +25,14 @@ static int sockfd = -1;
	#define LISTEN_RAW 2
	static smallint listen_mode;

+	#define INIT_SELECTING 0
+	#define REQUESTING 1
+	#define BOUND 2
+	#define RENEWING 3
+	#define REBINDING 4
+	#define INIT_REBOOT 5
+	#define RENEW_REQUESTED 6
+	#define RELEASED 7
	static smallint state;

	/* struct client_config_t client_config is in bb_common_bufsiz1 */
@@ -71,7 +76,7 @@ static void perform_renew(void)


	/* perform a release */
-	static void perform_release(void)
+	static void perform_release(uint32_t requested_ip, uint32_t server_addr)
	{
	char buffer[sizeof("255.255.255.255")];
	struct in_addr temp_addr;
@@ -90,7 +95,6 @@ static void perform_release(void)

	change_listen_mode(LISTEN_NONE);
	state = RELEASED;
-	timeout = INT_MAX;
	}


@@ -140,9 +144,12 @@ int udhcpc_main(int argc ATTRIBUTE_UNUSED, char **argv)
	int tryagain_timeout = 20;
	int discover_timeout = 3;
	int discover_retries = 3;
+	uint32_t server_addr = server_addr; /* for compiler */
+	uint32_t requested_ip = 0;
	uint32_t xid = 0;
	uint32_t lease_seconds = 0; /* can be given as 32-bit quantity */
	int packet_num;
+	int timeout; /* must be signed */
	unsigned already_waited_sec;
	unsigned opt;
	int max_fd;
@@ -332,6 +339,7 @@ int udhcpc_main(int argc ATTRIBUTE_UNUSED, char **argv)
	udhcp_run_script(NULL, "deconfig");
	change_listen_mode(LISTEN_RAW);
	packet_num = 0;
+	timeout = 0;
	already_waited_sec = 0;

	/* Main event loop. select() waits on signal pipe and possibly
@@ -510,8 +518,8 @@ int udhcpc_main(int argc ATTRIBUTE_UNUSED, char **argv)
	continue;
	/* still selecting - this server looks bad */
	}
-	/* can be misaligned, thus memcpy */
-	memcpy(&server_addr, temp, 4);
+	/* it IS unaligned sometimes, don't "optimize" */
+	server_addr = get_unaligned_u32p((uint32_t*)temp);
	xid = packet.xid;
	requested_ip = packet.yiaddr;

@@ -535,7 +543,9 @@ int udhcpc_main(int argc ATTRIBUTE_UNUSED, char **argv)
	/* can be misaligned, thus memcpy */
	memcpy(&lease_seconds, temp, 4);
	lease_seconds = ntohl(lease_seconds);
-	lease_seconds &= 0x0fffffff; /* paranoia: must not be negative */
+	lease_seconds &= 0x0fffffff; /* paranoia: must not be prone to overflows */
+	if (lease_seconds < 10) /* and not too small */
+	lease_seconds = 10;
	}
	#if ENABLE_FEATURE_UDHCPC_ARPING
	if (opt & OPT_a) {
@@ -576,7 +586,7 @@ int udhcpc_main(int argc ATTRIBUTE_UNUSED, char **argv)
	change_listen_mode(LISTEN_NONE);
	if (client_config.quit_after_lease) {
	if (client_config.release_on_quit)
-	perform_release();
+	perform_release(requested_ip, server_addr);
	goto ret0;
	}
	if (!client_config.foreground)
@@ -618,12 +628,13 @@ int udhcpc_main(int argc ATTRIBUTE_UNUSED, char **argv)
	timeout = 0;
	break;
	case SIGUSR2:
-	perform_release();
+	perform_release(requested_ip, server_addr);
+	timeout = INT_MAX;
	break;
	case SIGTERM:
	bb_info_msg("Received SIGTERM");
	if (client_config.release_on_quit)
-	perform_release();
+	perform_release(requested_ip, server_addr);
	goto ret0;
	}
	}

networking/udhcp/dhcpc.h+0 -9

@@ -8,15 +8,6 @@
	# pragma GCC visibility push(hidden)
	#endif

-	#define INIT_SELECTING 0
-	#define REQUESTING 1
-	#define BOUND 2
-	#define RENEWING 3
-	#define REBINDING 4
-	#define INIT_REBOOT 5
-	#define RENEW_REQUESTED 6
-	#define RELEASED 7
-
	struct client_config_t {
	/* TODO: combine flag fields into single "unsigned opt" */
	/* (can be set directly to the result of getopt32) */