[PATCH] LSM: add missing hook to do_compat_readv_writev()
This patch addresses a flaw in LSM, where there is no mediation of readv()
and writev() in for 32-bit compatible apps using a 64-bit kernel.
This bug was discovered and fixed initially in the native readv/writev
code [1], but was not fixed in the compat code. Thanks to Al for spotting
this one.
[1] http://lwn.net/Articles/154282/
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/compat.c b/fs/compat.c
index 7f8e26e..2e32bd3 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -1217,6 +1217,10 @@
if (ret < 0)
goto out;
+ ret = security_file_permission(file, type == READ ? MAY_READ:MAY_WRITE);
+ if (ret)
+ goto out;
+
fnv = NULL;
if (type == READ) {
fn = file->f_op->read;