From: Joey Hess <joey@kitenet.net>
Date: Sun, 23 Sep 2012 01:53:33 +0000 (-0400)
Subject: zgz: Don't hardcode /lib, avoid segfaulting on > 128 character paths
X-Git-Tag: 1.27~3
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d5f53a19a691551767c47aaabfaa264654fb81e9;p=tools%2Fpristine-tar.git

zgz: Don't hardcode /lib, avoid segfaulting on > 128 character paths

There were a number of issues with zgz:

* It had a fixed 128 (!) size limit on paths, and if we happened
  to be installed into one longer than that, the program would
  likely segfault.
* Calling exit(system()) is inefficient; we might as well just
  execve() and avoid having a process just blocked in waitpid()
  on another.
* We should honor LIBDIR, in order to support lib64-style "multilib"
  as well as full Debian-style "multiarch".

Based on a patch from Colin Walters <walters@verbum.org>
---

diff --git a/Makefile.PL b/Makefile.PL
index baef72a..60a5103 100755
--- a/Makefile.PL
+++ b/Makefile.PL
@@ -49,7 +49,8 @@ $(EXE_FILES): %:
 PHONY+=$(EXE_FILES)
 endif
 
-ZGZ_LIB=$(PREFIX)/lib/zgz
+LIBDIR ?= $(PREFIX)/lib
+PKGLIBDIR ?= $(LIBDIR)/pristine-tar
 
 extra_build: zgz/zgz pristine-tar.spec
 	pod2man -c pristine-tar pristine-tar > pristine-tar.1
@@ -61,16 +62,15 @@ extra_build: zgz/zgz pristine-tar.spec
 
 ZGZ_SOURCES = zgz/zgz.c zgz/gzip/*.c zgz/old-bzip2/*.c
 zgz/zgz: $(ZGZ_SOURCES)
-	gcc -Wall -O2 -o $@ $(ZGZ_SOURCES) -lz -DZGZ_LIB=\"$(ZGZ_LIB)\"
+	gcc -Wall -O2 -o $@ $(ZGZ_SOURCES) -lz -DPKGLIBDIR=\"$(PKGLIBDIR)\"
 
 extra_install:
 	install -d $(DESTDIR)$(PREFIX)/bin
 	install zgz/zgz $(DESTDIR)$(PREFIX)/bin
 	install -d $(DESTDIR)$(PREFIX)/share/man/man1
 	install -m 0644 *.1 $(DESTDIR)$(PREFIX)/share/man/man1
-	install -d $(DESTDIR)$(ZGZ_LIB)/suse-bzip2
-	install pit/suse-bzip2/bzip2 $(DESTDIR)$(ZGZ_LIB)/suse-bzip2
-	install pit/suse-bzip2/libbz2* $(DESTDIR)$(ZGZ_LIB)/suse-bzip2
+	install -d $(DESTDIR)$(PKGLIBDIR)/suse-bzip2
+	install pit/suse-bzip2/bzip2 pit/suse-bzip2/libbz2* $(DESTDIR)$(PKGLIBDIR)/suse-bzip2
 
 extra_clean:
 	$(MAKE) clean -C pit/suse-bzip2 PREFIX=$(PREFIX)
diff --git a/pristine-tar.spec b/pristine-tar.spec
index 2de867a..81d7c29 100644
--- a/pristine-tar.spec
+++ b/pristine-tar.spec
@@ -1,5 +1,5 @@
 Name: pristine-tar
-Version: 1.26
+Version: 1.27
 Release: 2%{?dist}
 Summary: regenerate pristine tarballs
 
diff --git a/zgz/zgz.c b/zgz/zgz.c
index 377b073..28ba166 100644
--- a/zgz/zgz.c
+++ b/zgz/zgz.c
@@ -131,8 +131,8 @@ static	void	gz_compress(int, int, const char *, uint32_t, int, int, int, int, in
 static	void	usage(void);
 static	void	display_version(void);
 static	void	display_license(void);
-static	void	shamble(char *, int, char *);
-static	void    rebrain(char *, char *, int, char *);
+static	void	shamble(char *, int);
+static	void    rebrain(char *, char *, int);
 
 int main(int, char **p);
 
@@ -341,9 +341,9 @@ main(int argc, char **argv)
 		}
 		old_bzip2(level);
 	} else if (bzsuse) {
-		shamble("suse-bzip2/bzip2", level, "");
+		shamble("suse-bzip2/bzip2", level);
 	} else if (pbzsuse) {
-		rebrain("suse-bzip2", "pbzip2", level, "");
+		rebrain("suse-bzip2", "pbzip2", level);
 	} else {
 		if (rsync || new_rsync) {
 			fprintf(stderr, "%s: --rsyncable not supported with --zlib\n", progname);
@@ -516,18 +516,34 @@ gz_compress(int in, int out, const char *origname, uint32_t mtime, int level, in
 
 /* runs an external, reanimated compressor program */
 static	void
-shamble(char *zombie, int level, char *opts)
+shamble(char *zombie, int level)
 {
-	char buf[128];
-	sprintf(buf, "%s/%s -%i %s", ZGZ_LIB, zombie, level, opts);
-	exit(system(buf));
+	char exec_buf[PATH_MAX];
+	char level_buf[3];
+	char *argv[3];
+	int i;
+
+	snprintf(exec_buf, sizeof(exec_buf), "%s/%s", PKGLIBDIR, zombie);
+	snprintf(level_buf, sizeof(level_buf), "-%i", level);
+
+	i = 0;
+	argv[i++] = exec_buf;
+	argv[i++] = level_buf;
+	argv[i++] = NULL;
+
+	execvp(exec_buf, argv);
+	perror("Failed to run external program");
+	exit(1);
 }
 
 /* swaps in a different library and runs a system program */
 static	void
-rebrain(char *zombie, char *program, int level, char *opts)
+rebrain(char *zombie, char *program, int level)
 {
-	char buf[128];
+	char path_buf[PATH_MAX];
+	char level_buf[3];
+	char *argv[3];
+	int i;
 
 #if defined(__APPLE__) && defined(__MACH__)
 #	define LD_PATH_VAR "DYLD_LIBRARY_PATH" 
@@ -535,9 +551,20 @@ rebrain(char *zombie, char *program, int level, char *opts)
 #	define LD_PATH_VAR "LD_LIBRARY_PATH"
 #endif
 
-	sprintf(buf, LD_PATH_VAR "=%s/%s %s -%i %s",
-			ZGZ_LIB, zombie, program, level, opts);
-	exit(system(buf));
+	snprintf(path_buf, sizeof(path_buf), "%s/%s", PKGLIBDIR, zombie);
+	/* FIXME - should append, not overwrite */
+	setenv(LD_PATH_VAR, path_buf, 1);
+
+	snprintf(level_buf, sizeof(level_buf), "-%i", level);
+
+	i = 0;
+	argv[i++] = program;
+	argv[i++] = level_buf;
+	argv[i++] = NULL;
+
+	execvp(program, argv);
+	perror("Failed to run external program");
+	exit(1);
 }
 
 /* display usage */