Eliminate the prefix parameter to linux_emul_find(), which was always

linux_emul_path anyway.  Linux_emul_find() has interesting bugs in its
prefix handling (which luckily are not currently exploitable); this
commit is preliminary to an attempt at cleaning it up.

Approved by:	marcel

2 files changed, 5 insertions, 7 deletions

diff --git a/sys/compat/linux/linux_util.c b/sys/compat/linux/linux_util.c
index 45c85b6..c30d0f4 100644
--- a/sys/compat/linux/linux_util.c
+++ b/sys/compat/linux/linux_util.c
@@ -50,10 +50,9 @@ const char      linux_emul_path[] = "/compat/linux";
  * be in exists.
  */
 int
-linux_emul_find(td, sgp, prefix, path, pbuf, cflag)
+linux_emul_find(td, sgp, path, pbuf, cflag)
 	struct thread	 *td;
 	caddr_t		 *sgp;		/* Pointer to stackgap memory */
-	const char	 *prefix;
 	char		 *path;
 	char		**pbuf;
 	int		  cflag;
@@ -63,15 +62,16 @@ linux_emul_find(td, sgp, prefix, path, pbuf, cflag)
 	struct vattr		 vat;
 	struct vattr		 vatroot;
 	int			 error;
+	const char		*prefix;
 	char			*ptr, *buf, *cp;
 	size_t			 sz, len;
 
 	buf = (char *) malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
 	*pbuf = path;
 
+	prefix = linux_emul_path;
 	for (ptr = buf; (*ptr = *prefix) != '\0'; ptr++, prefix++)
 		continue;
-
 	sz = MAXPATHLEN - (ptr - buf);
 
 	/* 
diff --git a/sys/compat/linux/linux_util.h b/sys/compat/linux/linux_util.h
index 43aed1f..e01f260 100644
--- a/sys/compat/linux/linux_util.h
+++ b/sys/compat/linux/linux_util.h
@@ -76,15 +76,13 @@ stackgap_alloc(sgp, sz)
 
 extern const char linux_emul_path[];
 
-int linux_emul_find __P((struct thread *, caddr_t *, const char *, char *,
-			char **, int));
+int linux_emul_find __P((struct thread *, caddr_t *, char *, char **, int));
 
 #define CHECKALT(p, sgp, path, i) 					\
 	do {								\
 		int _error;						\
 									\
-		_error = linux_emul_find(p, sgp, linux_emul_path, path,	\
-		    &path, i);						\
+		_error = linux_emul_find(p, sgp, path, &path, i);	\
 		if (_error == EFAULT)					\
 			return (_error);				\
 	} while (0)