Commit b04ea3ce authored Jul 14, 2006 by Eric Paris Committed by Linus Torvalds Jul 14, 2006

[PATCH] Fix security check for joint context= and fscontext= mount options



After some discussion on the actual meaning of the filesystem class
security check in try context mount it was determined that the checks for
the context= mount options were not correct if fscontext mount option had
already been used.

When labeling the superblock we should be checking relabel_from and
relabel_to.  But if the superblock has already been labeled (with
fscontext) then context= is actually labeling the inodes, and so we should
be checking relabel_from and associate.  This patch fixes which checks are
called depending on the mount options.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 517e7aa5

security/selinux/hooks.c

+9 −5

Original line number	Diff line number	Diff line
		@@ -523,12 +523,16 @@ static int try_context_mount(struct super_block sb, void data)
		goto out_free;
		}

		if (!fscontext) {
		rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
		if (rc)
		goto out_free;

		if (!fscontext)
		sbsec->sid = sid;
		} else {
		rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
		if (rc)
		goto out_free;
		}
		sbsec->mntpoint_sid = sid;

		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;