From 3fbfa98112fc3962c416452a0baf2214381030e6 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 14 Feb 2007 00:34:14 -0800 Subject: [PATCH] sysctl: remove the proc_dir_entry member for the sysctl tables It isn't needed anymore, all of the users are gone, and all of the ctl_table initializers have been converted to use explicit names of the fields they are initializing. [akpm@osdl.org: NTFS fix] Signed-off-by: Eric W. Biederman Acked-by: Stephen Smalley Cc: James Morris Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/selinux/hooks.c | 39 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 37 insertions(+), 2 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 35eb8de892fc..118ddfb614ee 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1423,6 +1423,41 @@ static int selinux_capable(struct task_struct *tsk, int cap) return task_has_capability(tsk,cap); } +static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) +{ + int buflen, rc; + char *buffer, *path, *end; + + rc = -ENOMEM; + buffer = (char*)__get_free_page(GFP_KERNEL); + if (!buffer) + goto out; + + buflen = PAGE_SIZE; + end = buffer+buflen; + *--end = '\0'; + buflen--; + path = end-1; + *path = '/'; + while (table) { + const char *name = table->procname; + size_t namelen = strlen(name); + buflen -= namelen + 1; + if (buflen < 0) + goto out_free; + end -= namelen; + memcpy(end, name, namelen); + *--end = '/'; + path = end; + table = table->parent; + } + rc = security_genfs_sid("proc", path, tclass, sid); +out_free: + free_page((unsigned long)buffer); +out: + return rc; +} + static int selinux_sysctl(ctl_table *table, int op) { int error = 0; @@ -1437,8 +1472,8 @@ static int selinux_sysctl(ctl_table *table, int op) tsec = current->security; - rc = selinux_proc_get_sid(table->de, (op == 001) ? - SECCLASS_DIR : SECCLASS_FILE, &tsid); + rc = selinux_sysctl_get_sid(table, (op == 0001) ? + SECCLASS_DIR : SECCLASS_FILE, &tsid); if (rc) { /* Default to the well-defined sysctl SID. */ tsid = SECINITSID_SYSCTL; -- cgit v1.2.3 From b599fdfdb4bb4941e9076308efcf3bb89e577db5 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 14 Feb 2007 00:34:15 -0800 Subject: [PATCH] sysctl: fix the selinux_sysctl_get_sid I goofed and when reenabling the fine grained selinux labels for sysctls and forgot to add the "/sys" prefix before consulting the policy database. When computing the same path using proc_dir_entries we got the "/sys" for free as it was part of the tree, but it isn't true for clt_table trees. Signed-off-by: Eric W. Biederman Acked-by: Stephen Smalley Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/selinux/hooks.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 118ddfb614ee..b8ede1c7607b 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1451,6 +1451,12 @@ static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid) path = end; table = table->parent; } + buflen -= 4; + if (buflen < 0) + goto out_free; + end -= 4; + memcpy(end, "/sys", 4); + path = end; rc = security_genfs_sid("proc", path, tclass, sid); out_free: free_page((unsigned long)buffer); -- cgit v1.2.3 From bbaca6c2e7ef0f663bc31be4dad7cf530f6c4962 Mon Sep 17 00:00:00 2001 From: Stephen Smalley Date: Wed, 14 Feb 2007 00:34:16 -0800 Subject: [PATCH] selinux: enhance selinux to always ignore private inodes 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 Signed-off-by: Stephen Smalley Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- security/selinux/hooks.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index b8ede1c7607b..b1ac22d23195 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; -- cgit v1.2.3