commit 08a6fac1c63233c87eec129938022f1a9a4d51f6
author Al Viro <viro@zeniv.linux.org.uk> Sat May 10 16:38:25 2008 -0400
committer Al Viro <viro@zeniv.linux.org.uk> Fri May 16 17:23:05 2008 -0400
tree 4fd7a2a906cf5ca0a42b3b8cb30351465f0f6cee
parent 5f719558edf9c84bfbb1f7ad37e84c483282d09f

[PATCH] get rid of leak in compat_execve()

Even though copy_compat_strings() doesn't cache the pages,
copy_strings_kernel() and stuff indirectly called by e.g.
->load_binary() is doing that, so we need to drop the
cache contents in the end.

[found by WANG Cong <wangcong@zeuux.org>]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/compat.c

diff --git a/fs/compat.c b/fs/compat.c
index 332a869..ed43e17 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -1405,7 +1405,7 @@
 		/* execve success */
 		security_bprm_free(bprm);
 		acct_update_integrals(current);
-		kfree(bprm);
+		free_bprm(bprm);
 		return retval;
 	}
 
@@ -1424,7 +1424,7 @@
 	}
 
 out_kfree:
-	kfree(bprm);
+	free_bprm(bprm);
 
 out_ret:
 	return retval;

fs/exec.c

diff --git a/fs/exec.c b/fs/exec.c
index 1f8a24a..3c2ba7c 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1251,6 +1251,12 @@
 
 EXPORT_SYMBOL(search_binary_handler);
 
+void free_bprm(struct linux_binprm *bprm)
+{
+	free_arg_pages(bprm);
+	kfree(bprm);
+}
+
 /*
  * sys_execve() executes a new program.
  */
@@ -1320,17 +1326,15 @@
 	retval = search_binary_handler(bprm,regs);
 	if (retval >= 0) {
 		/* execve success */
-		free_arg_pages(bprm);
 		security_bprm_free(bprm);
 		acct_update_integrals(current);
-		kfree(bprm);
+		free_bprm(bprm);
 		if (displaced)
 			put_files_struct(displaced);
 		return retval;
 	}
 
 out:
-	free_arg_pages(bprm);
 	if (bprm->security)
 		security_bprm_free(bprm);
 
@@ -1344,7 +1348,7 @@
 		fput(bprm->file);
 	}
 out_kfree:
-	kfree(bprm);
+	free_bprm(bprm);
 
 out_files:
 	if (displaced)