← Commit list

bc28f7a1e

Robert Griebl

2002-06-04

FAILED Duration: 131s

Subject

Cleaned up Erik's fgets -> read patch and fixed a buffer overflow

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 →

modutils/modprobe.c +38 -36

modutils/modprobe.c+38 -36

@@ -44,9 +44,38 @@ static struct dep_t *depend;
	static int autoclean, show_only, quiet, do_syslog, verbose;


+	/* Jump through hoops to simulate how fgets() grabs just one line at a
+	* time... Don't use any stdio since modprobe gets called from a kernel
+	* thread and stdio junk can overflow the limited stack...
+	*/
+	static char reads ( int fd, char buffer, size_t len )
+	{
+	int n = read ( fd, buffer, len );
+
+	if ( n > 0 ) {
+	char *p;
+
+	buffer [len-1] = 0;
+	p = strchr ( buffer, '\n' );
+
+	if ( p ) {
+	off_t offset;
+
+	offset = lseek ( fd, 0L, SEEK_CUR ); // Get the current file descriptor offset
+	lseek ( fd, offset-n + (p-buffer) + 1, SEEK_SET ); // Set the file descriptor offset to right after the \n
+
+	p[1] = 0;
+	}
+	return buffer;
+	}
+
+	else
+	return 0;
+	}
+
	static struct dep_t *build_dep ( void )
	{
-	int fd, n;
+	int fd;
	struct utsname un;
	struct dep_t *first = 0;
	struct dep_t *current = 0;
@@ -66,27 +95,13 @@ static struct dep_t *build_dep ( void )
	strcat ( filename, un.release );
	strcat ( filename, "/modules.dep" );

-	if ((fd = open ( filename, O_RDONLY )) < 0)
+	if (( fd = open ( filename, O_RDONLY )) < 0 )
	return 0;

-	while ( (n = read(fd, buffer, 255)) > 0) {
-	int l;
+	while ( reads ( fd, buffer, sizeof( buffer ))) {
+	int l = xstrlen ( buffer );
	char *p = 0;
-
-	/* Jump through hoops to simulate how fgets() grabs just one line at a
-	* time... Don't use any stdio since modprobe gets called from a kernel
-	* thread and stdio junk can overflow the limited stack... */
-	p = strchr ( buffer, '\n' );
-	if (p) {
-	off_t offset;
-	/* Get the current file descriptor offset */
-	offset = lseek(fd, 0L, SEEK_CUR);
-	/* Set the file descriptor offset to right after the \n */
-	lseek(fd, offset-n+p-buffer+1, SEEK_SET);
-	*(p+1)='\0';
-	}
-
-	l = xstrlen ( buffer );
+
	while ( isspace ( buffer [l-1] )) {
	buffer [l-1] = 0;
	l--;
@@ -182,29 +197,16 @@ static struct dep_t *build_dep ( void )

	// alias parsing is not 100% correct (no correct handling of continuation lines within an alias) !

-	if ((fd = open ( "/etc/modules.conf", O_RDONLY )) < 0)
-	if ((fd = open ( "/etc/conf.modules", O_RDONLY )) < 0)
+	if (( fd = open ( "/etc/modules.conf", O_RDONLY )) < 0 )
+	if (( fd = open ( "/etc/conf.modules", O_RDONLY )) < 0 )
	return first;

	continuation_line = 0;
-	while ( read(fd, buffer, 255) > 0) {
+	while ( reads ( fd, buffer, sizeof( buffer ))) {
	int l;
	char *p;

-	/* Jump through hoops to simulate how fgets() grabs just one line at a
-	* time... Don't use any stdio since modprobe gets called from a kernel
-	* thread and stdio junk can overflow the limited stack... */
-	p = strchr ( buffer, '\n' );
-	if (p) {
-	off_t offset;
-	/* Get the current file descriptor offset */
-	offset = lseek(fd, 0L, SEEK_CUR);
-	/* Set the file descriptor offset to right after the \n */
-	lseek(fd, offset-n+p-buffer+1, SEEK_SET);
-	*(p+1)='\0';
-	}
-
-	p = strchr ( buffer, '#' );
+	p = strchr ( buffer, '#' );
	if ( p )
	*p = 0;