svn commit: r234186 - head/sys/kern

[John Baldwin]

Author: jhb
Date: Thu Apr 12 14:49:25 2012
New Revision: 234186
URL: http://svn.freebsd.org/changeset/base/234186

Log:
  If a linker file contains at least one module, but all of the modules
  fail to load (the MOD_LOAD event fails) during a kldload(2), unload the
  linker file and fail the kldload(2) with ENOEXEC.
  
  Reported by:	gcooper
  MFC after:	1 week

Modified:
  head/sys/kern/kern_linker.c

Modified: head/sys/kern/kern_linker.c
==============================================================================
--- head/sys/kern/kern_linker.c	Thu Apr 12 14:06:05 2012	(r234185)
+++ head/sys/kern/kern_linker.c	Thu Apr 12 14:49:25 2012	(r234186)
@@ -380,7 +380,7 @@ linker_load_file(const char *filename, l
 {
 	linker_class_t lc;
 	linker_file_t lf;
-	int foundfile, error;
+	int foundfile, error, modules;
 
 	/* Refuse to load modules if securelevel raised */
 	if (prison0.pr_securelevel > 0)
@@ -419,11 +419,22 @@ linker_load_file(const char *filename, l
 				linker_file_unload(lf, LINKER_UNLOAD_FORCE);
 				return (error);
 			}
+			modules = !TAILQ_EMPTY(&lf->modules);
 			KLD_UNLOCK();
 			linker_file_register_sysctls(lf);
 			linker_file_sysinit(lf);
 			KLD_LOCK();
 			lf->flags |= LINKER_FILE_LINKED;
+
+			/*
+			 * If all of the modules in this file failed
+			 * to load, unload the file and return an
+			 * error of ENOEXEC.
+			 */
+			if (modules && TAILQ_EMPTY(&lf->modules)) {
+				linker_file_unload(lf, LINKER_UNLOAD_FORCE);
+				return (ENOEXEC);
+			}
 			*result = lf;
 			return (0);
 		}
@@ -627,7 +638,7 @@ linker_file_unload(linker_file_t file, i
 
 	/*
 	 * Inform any modules associated with this file that they are
-	 * being be unloaded.
+	 * being unloaded.
 	 */
 	MOD_XLOCK;
 	for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) {