Messages in this thread Patch in this message | | | From | (Eric W. Biederman) | Subject | [PATCH 4/5] selinux: Enhance selinux to always ignore private inodes. | Date | Thu, 08 Feb 2007 16:02:58 -0700 |
| |
From: Stephen Smalley <sds@tycho.nsa.gov>
Hmmm...turns out to not be quite enough, as the /proc/sys inodes aren't truly private to the fs, so we can run into them in a variety of security hooks beyond just the inode hooks, such as security_file_permission (when reading and writing them via the vfs helpers), security_sb_mount (when mounting other filesystems on directories in proc like binfmt_misc), and deeper within the security module itself (as in flush_unauthorized_files upon inheritance across execve). So I think we have to add an IS_PRIVATE() guard within SELinux, as below. Note however that the use of the private flag here could be confusing, as these inodes are _not_ private to the fs, are exposed to userspace, and security modules must implement the sysctl hook to get any access control over them.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
--- security/selinux/hooks.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index de16b9f..ff9fccc 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1077,6 +1077,9 @@ static int inode_has_perm(struct task_struct *tsk, struct inode_security_struct *isec; struct avc_audit_data ad; + if (unlikely (IS_PRIVATE (inode))) + return 0; + tsec = tsk->security; isec = inode->i_security; -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |