Gitweb:     
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=b53767719b6cd8789392ea3e7e2eb7b8906898f0
Commit:     b53767719b6cd8789392ea3e7e2eb7b8906898f0
Parent:     57c521ce6125e15e99e56c902cb8da96bee7b36d
Author:     Serge E. Hallyn <[EMAIL PROTECTED]>
AuthorDate: Tue Oct 16 23:31:36 2007 -0700
Committer:  Linus Torvalds <[EMAIL PROTECTED]>
CommitDate: Wed Oct 17 08:43:07 2007 -0700

    Implement file posix capabilities
    
    Implement file posix capabilities.  This allows programs to be given a
    subset of root's powers regardless of who runs them, without having to use
    setuid and giving the binary all of root's powers.
    
    This version works with Kaigai Kohei's userspace tools, found at
    http://www.kaigai.gr.jp/index.php.  For more information on how to use this
    patch, Chris Friedhoff has posted a nice page at
    http://www.friedhoff.org/fscaps.html.
    
    Changelog:
        Nov 27:
        Incorporate fixes from Andrew Morton
        (security-introduce-file-caps-tweaks and
        security-introduce-file-caps-warning-fix)
        Fix Kconfig dependency.
        Fix change signaling behavior when file caps are not compiled in.
    
        Nov 13:
        Integrate comments from Alexey: Remove CONFIG_ ifdef from
        capability.h, and use %zd for printing a size_t.
    
        Nov 13:
        Fix endianness warnings by sparse as suggested by Alexey
        Dobriyan.
    
        Nov 09:
        Address warnings of unused variables at cap_bprm_set_security
        when file capabilities are disabled, and simultaneously clean
        up the code a little, by pulling the new code into a helper
        function.
    
        Nov 08:
        For pointers to required userspace tools and how to use
        them, see http://www.friedhoff.org/fscaps.html.
    
        Nov 07:
        Fix the calculation of the highest bit checked in
        check_cap_sanity().
    
        Nov 07:
        Allow file caps to be enabled without CONFIG_SECURITY, since
        capabilities are the default.
        Hook cap_task_setscheduler when !CONFIG_SECURITY.
        Move capable(TASK_KILL) to end of cap_task_kill to reduce
        audit messages.
    
        Nov 05:
        Add secondary calls in selinux/hooks.c to task_setioprio and
        task_setscheduler so that selinux and capabilities with file
        cap support can be stacked.
    
        Sep 05:
        As Seth Arnold points out, uid checks are out of place
        for capability code.
    
        Sep 01:
        Define task_setscheduler, task_setioprio, cap_task_kill, and
        task_setnice to make sure a user cannot affect a process in which
        they called a program with some fscaps.
    
        One remaining question is the note under task_setscheduler: are we
        ok with CAP_SYS_NICE being sufficient to confine a process to a
        cpuset?
    
        It is a semantic change, as without fsccaps, attach_task doesn't
        allow CAP_SYS_NICE to override the uid equivalence check.  But since
        it uses security_task_setscheduler, which elsewhere is used where
        CAP_SYS_NICE can be used to override the uid equivalence check,
        fixing it might be tough.
    
             task_setscheduler
                 note: this also controls cpuset:attach_task.  Are we ok with
                     CAP_SYS_NICE being used to confine to a cpuset?
             task_setioprio
             task_setnice
                 sys_setpriority uses this (through set_one_prio) for another
                 process.  Need same checks as setrlimit
    
        Aug 21:
        Updated secureexec implementation to reflect the fact that
        euid and uid might be the same and nonzero, but the process
        might still have elevated caps.
    
        Aug 15:
        Handle endianness of xattrs.
        Enforce capability version match between kernel and disk.
        Enforce that no bits beyond the known max capability are
        set, else return -EPERM.
        With this extra processing, it may be worth reconsidering
        doing all the work at bprm_set_security rather than
        d_instantiate.
    
        Aug 10:
        Always call getxattr at bprm_set_security, rather than
        caching it at d_instantiate.
    
    [EMAIL PROTECTED]: file-caps clean up for linux/capability.h]
    [EMAIL PROTECTED]: unexport cap_inode_killpriv]
    Signed-off-by: Serge E. Hallyn <[EMAIL PROTECTED]>
    Cc: Stephen Smalley <[EMAIL PROTECTED]>
    Cc: James Morris <[EMAIL PROTECTED]>
    Cc: Chris Wright <[EMAIL PROTECTED]>
    Cc: Andrew Morgan <[EMAIL PROTECTED]>
    Signed-off-by: Andrew Morgan <[EMAIL PROTECTED]>
    Signed-off-by: Adrian Bunk <[EMAIL PROTECTED]>
    Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
    Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]>
---
 fs/attr.c                  |    9 ++
 fs/nfsd/vfs.c              |    4 +-
 fs/open.c                  |    3 +-
 fs/splice.c                |   13 ++-
 include/linux/binfmts.h    |    3 +-
 include/linux/capability.h |   48 ++++++---
 include/linux/fs.h         |    1 +
 include/linux/security.h   |   40 +++++++-
 mm/filemap.c               |   14 ++-
 security/Kconfig           |   10 ++
 security/capability.c      |    6 +
 security/commoncap.c       |  244 +++++++++++++++++++++++++++++++++++++++++---
 security/dummy.c           |   12 ++
 security/security.c        |   10 ++
 security/selinux/hooks.c   |   74 +++++++++-----
 15 files changed, 418 insertions(+), 73 deletions(-)

diff --git a/fs/attr.c b/fs/attr.c
index f8dfc22..ae58bd3 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -116,6 +116,15 @@ int notify_change(struct dentry * dentry, struct iattr * 
attr)
                attr->ia_atime = now;
        if (!(ia_valid & ATTR_MTIME_SET))
                attr->ia_mtime = now;
+       if (ia_valid & ATTR_KILL_PRIV) {
+               attr->ia_valid &= ~ATTR_KILL_PRIV;
+               ia_valid &= ~ATTR_KILL_PRIV;
+               error = security_inode_need_killpriv(dentry);
+               if (error > 0)
+                       error = security_inode_killpriv(dentry);
+               if (error)
+                       return error;
+       }
        if (ia_valid & ATTR_KILL_SUID) {
                attr->ia_valid &= ~ATTR_KILL_SUID;
                if (mode & S_ISUID) {
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 1d72f99..819545d 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -368,7 +368,7 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, 
struct iattr *iap,
 
        /* Revoke setuid/setgid bit on chown/chgrp */
        if ((iap->ia_valid & ATTR_UID) && iap->ia_uid != inode->i_uid)
-               iap->ia_valid |= ATTR_KILL_SUID;
+               iap->ia_valid |= ATTR_KILL_SUID | ATTR_KILL_PRIV;
        if ((iap->ia_valid & ATTR_GID) && iap->ia_gid != inode->i_gid)
                iap->ia_valid |= ATTR_KILL_SGID;
 
@@ -937,7 +937,7 @@ out:
 static void kill_suid(struct dentry *dentry)
 {
        struct iattr    ia;
-       ia.ia_valid = ATTR_KILL_SUID | ATTR_KILL_SGID;
+       ia.ia_valid = ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV;
 
        mutex_lock(&dentry->d_inode->i_mutex);
        notify_change(dentry, &ia);
diff --git a/fs/open.c b/fs/open.c
index cdbb94a..7538514 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -658,7 +658,8 @@ static int chown_common(struct dentry * dentry, uid_t user, 
gid_t group)
                newattrs.ia_gid = group;
        }
        if (!S_ISDIR(inode->i_mode))
-               newattrs.ia_valid |= ATTR_KILL_SUID|ATTR_KILL_SGID;
+               newattrs.ia_valid |=
+                       ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV;
        mutex_lock(&inode->i_mutex);
        error = notify_change(dentry, &newattrs);
        mutex_unlock(&inode->i_mutex);
diff --git a/fs/splice.c b/fs/splice.c
index 59a941d..6bdcb61 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -824,13 +824,18 @@ generic_file_splice_write(struct pipe_inode_info *pipe, 
struct file *out,
 {
        struct address_space *mapping = out->f_mapping;
        struct inode *inode = mapping->host;
+       int killsuid, killpriv;
        ssize_t ret;
-       int err;
+       int err = 0;
 
-       err = should_remove_suid(out->f_path.dentry);
-       if (unlikely(err)) {
+       killpriv = security_inode_need_killpriv(out->f_path.dentry);
+       killsuid = should_remove_suid(out->f_path.dentry);
+       if (unlikely(killsuid || killpriv)) {
                mutex_lock(&inode->i_mutex);
-               err = __remove_suid(out->f_path.dentry, err);
+               if (killpriv)
+                       err = security_inode_killpriv(out->f_path.dentry);
+               if (!err && killsuid)
+                       err = __remove_suid(out->f_path.dentry, killsuid);
                mutex_unlock(&inode->i_mutex);
                if (err)
                        return err;
diff --git a/include/linux/binfmts.h b/include/linux/binfmts.h
index 3a6512f..b7fc55e 100644
--- a/include/linux/binfmts.h
+++ b/include/linux/binfmts.h
@@ -37,7 +37,8 @@ struct linux_binprm{
        int sh_bang;
        struct file * file;
        int e_uid, e_gid;
-       kernel_cap_t cap_inheritable, cap_permitted, cap_effective;
+       kernel_cap_t cap_inheritable, cap_permitted;
+       bool cap_effective;
        void *security;
        int argc, envc;
        char * filename;        /* Name of binary as seen by procps */
diff --git a/include/linux/capability.h b/include/linux/capability.h
index 2dfa585..8961e7f 100644
--- a/include/linux/capability.h
+++ b/include/linux/capability.h
@@ -1,14 +1,14 @@
 /*
  * This is <linux/capability.h>
  *
- * Andrew G. Morgan <[EMAIL PROTECTED]>
+ * Andrew G. Morgan <[EMAIL PROTECTED]>
  * Alexander Kjeldaas <[EMAIL PROTECTED]>
  * with help from Aleph1, Roland Buresund and Andrew Main.
  *
  * See here for the libcap library ("POSIX draft" compliance):
  *
- * ftp://linux.kernel.org/pub/linux/libs/security/linux-privs/kernel-2.2/
- */ 
+ * ftp://linux.kernel.org/pub/linux/libs/security/linux-privs/kernel-2.6/
+ */
 
 #ifndef _LINUX_CAPABILITY_H
 #define _LINUX_CAPABILITY_H
@@ -28,23 +28,41 @@ struct task_struct;
    following structure to such a composite is better handled in a user
    library since the draft standard requires the use of malloc/free
    etc.. */
- 
+
 #define _LINUX_CAPABILITY_VERSION  0x19980330
 
 typedef struct __user_cap_header_struct {
        __u32 version;
        int pid;
 } __user *cap_user_header_t;
- 
+
 typedef struct __user_cap_data_struct {
         __u32 effective;
         __u32 permitted;
         __u32 inheritable;
 } __user *cap_user_data_t;
-  
-#ifdef __KERNEL__
 
-#include <asm/current.h>
+#define XATTR_CAPS_SUFFIX "capability"
+#define XATTR_NAME_CAPS XATTR_SECURITY_PREFIX XATTR_CAPS_SUFFIX
+
+#define XATTR_CAPS_SZ (3*sizeof(__le32))
+#define VFS_CAP_REVISION_MASK  0xFF000000
+#define VFS_CAP_REVISION_1     0x01000000
+
+#define VFS_CAP_REVISION       VFS_CAP_REVISION_1
+
+#define VFS_CAP_FLAGS_MASK     ~VFS_CAP_REVISION_MASK
+#define VFS_CAP_FLAGS_EFFECTIVE        0x000001
+
+struct vfs_cap_data {
+       __u32 magic_etc;  /* Little endian */
+       struct {
+               __u32 permitted;    /* Little endian */
+               __u32 inheritable;  /* Little endian */
+       } data[1];
+};
+
+#ifdef __KERNEL__
 
 /* #define STRICT_CAP_T_TYPECHECKS */
 
@@ -59,7 +77,7 @@ typedef struct kernel_cap_struct {
 typedef __u32 kernel_cap_t;
 
 #endif
-  
+
 #define _USER_CAP_HEADER_SIZE  (2*sizeof(__u32))
 #define _KERNEL_CAP_T_SIZE     (sizeof(kernel_cap_t))
 
@@ -67,7 +85,7 @@ typedef __u32 kernel_cap_t;
 
 
 /**
- ** POSIX-draft defined capabilities. 
+ ** POSIX-draft defined capabilities.
  **/
 
 /* In a system with the [_POSIX_CHOWN_RESTRICTED] option defined, this
@@ -87,7 +105,7 @@ typedef __u32 kernel_cap_t;
    defined. Excluding DAC access covered by CAP_LINUX_IMMUTABLE. */
 
 #define CAP_DAC_READ_SEARCH  2
-    
+
 /* Overrides all restrictions about allowed operations on files, where
    file owner ID must be equal to the user ID, except where CAP_FSETID
    is applicable. It doesn't override MAC and DAC restrictions. */
@@ -257,7 +275,7 @@ typedef __u32 kernel_cap_t;
 /* Override reserved space on ext2 filesystem */
 /* Modify data journaling mode on ext3 filesystem (uses journaling
    resources) */
-/* NOTE: ext2 honors fsuid when checking for resource overrides, so 
+/* NOTE: ext2 honors fsuid when checking for resource overrides, so
    you can override using fsuid too */
 /* Override size restrictions on IPC message queues */
 /* Allow more than 64hz interrupts from the real-time clock */
@@ -289,8 +307,10 @@ typedef __u32 kernel_cap_t;
 
 #define CAP_AUDIT_CONTROL    30
 
+#define CAP_SETFCAP         31
+
 #ifdef __KERNEL__
-/* 
+/*
  * Bounding set
  */
 extern kernel_cap_t cap_bset;
@@ -298,7 +318,7 @@ extern kernel_cap_t cap_bset;
 /*
  * Internal kernel functions only
  */
- 
+
 #ifdef STRICT_CAP_T_TYPECHECKS
 
 #define to_cap_t(x) { x }
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 365586a..e3fc5db 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -329,6 +329,7 @@ typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t 
offset,
 #define ATTR_KILL_SUID 2048
 #define ATTR_KILL_SGID 4096
 #define ATTR_FILE      8192
+#define ATTR_KILL_PRIV 16384
 
 /*
  * This is the Inode Attributes structure, used for notify_change().  It
diff --git a/include/linux/security.h b/include/linux/security.h
index a300a3f..df591d2 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -51,8 +51,14 @@ extern void cap_bprm_apply_creds (struct linux_binprm *bprm, 
int unsafe);
 extern int cap_bprm_secureexec(struct linux_binprm *bprm);
 extern int cap_inode_setxattr(struct dentry *dentry, char *name, void *value, 
size_t size, int flags);
 extern int cap_inode_removexattr(struct dentry *dentry, char *name);
+extern int cap_inode_need_killpriv(struct dentry *dentry);
+extern int cap_inode_killpriv(struct dentry *dentry);
 extern int cap_task_post_setuid (uid_t old_ruid, uid_t old_euid, uid_t 
old_suid, int flags);
 extern void cap_task_reparent_to_init (struct task_struct *p);
+extern int cap_task_kill(struct task_struct *p, struct siginfo *info, int sig, 
u32 secid);
+extern int cap_task_setscheduler (struct task_struct *p, int policy, struct 
sched_param *lp);
+extern int cap_task_setioprio (struct task_struct *p, int ioprio);
+extern int cap_task_setnice (struct task_struct *p, int nice);
 extern int cap_syslog (int type);
 extern int cap_vm_enough_memory(struct mm_struct *mm, long pages);
 
@@ -413,6 +419,18 @@ struct request_sock;
  *     is specified by @buffer_size.  @buffer may be NULL to request
  *     the size of the buffer required.
  *     Returns number of bytes used/required on success.
+ * @inode_need_killpriv:
+ *     Called when an inode has been changed.
+ *     @dentry is the dentry being changed.
+ *     Return <0 on error to abort the inode change operation.
+ *     Return 0 if inode_killpriv does not need to be called.
+ *     Return >0 if inode_killpriv does need to be called.
+ * @inode_killpriv:
+ *     The setuid bit is being removed.  Remove similar security labels.
+ *     Called with the dentry->d_inode->i_mutex held.
+ *     @dentry is the dentry being changed.
+ *     Return 0 on success.  If error is returned, then the operation
+ *     causing setuid bit removal is failed.
  *
  * Security hooks for file operations
  *
@@ -1239,6 +1257,8 @@ struct security_operations {
        int (*inode_getxattr) (struct dentry *dentry, char *name);
        int (*inode_listxattr) (struct dentry *dentry);
        int (*inode_removexattr) (struct dentry *dentry, char *name);
+       int (*inode_need_killpriv) (struct dentry *dentry);
+       int (*inode_killpriv) (struct dentry *dentry);
        const char *(*inode_xattr_getsuffix) (void);
        int (*inode_getsecurity)(const struct inode *inode, const char *name, 
void *buffer, size_t size, int err);
        int (*inode_setsecurity)(struct inode *inode, const char *name, const 
void *value, size_t size, int flags);
@@ -1496,6 +1516,8 @@ void security_inode_post_setxattr(struct dentry *dentry, 
char *name,
 int security_inode_getxattr(struct dentry *dentry, char *name);
 int security_inode_listxattr(struct dentry *dentry);
 int security_inode_removexattr(struct dentry *dentry, char *name);
+int security_inode_need_killpriv(struct dentry *dentry);
+int security_inode_killpriv(struct dentry *dentry);
 const char *security_inode_xattr_getsuffix(void);
 int security_inode_getsecurity(const struct inode *inode, const char *name, 
void *buffer, size_t size, int err);
 int security_inode_setsecurity(struct inode *inode, const char *name, const 
void *value, size_t size, int flags);
@@ -1891,6 +1913,16 @@ static inline int security_inode_removexattr (struct 
dentry *dentry, char *name)
        return cap_inode_removexattr(dentry, name);
 }
 
+static inline int security_inode_need_killpriv(struct dentry *dentry)
+{
+       return cap_inode_need_killpriv(dentry);
+}
+
+static inline int security_inode_killpriv(struct dentry *dentry)
+{
+       return cap_inode_killpriv(dentry);
+}
+
 static inline const char *security_inode_xattr_getsuffix (void)
 {
        return NULL ;
@@ -2035,12 +2067,12 @@ static inline int security_task_setgroups (struct 
group_info *group_info)
 
 static inline int security_task_setnice (struct task_struct *p, int nice)
 {
-       return 0;
+       return cap_task_setnice(p, nice);
 }
 
 static inline int security_task_setioprio (struct task_struct *p, int ioprio)
 {
-       return 0;
+       return cap_task_setioprio(p, ioprio);
 }
 
 static inline int security_task_getioprio (struct task_struct *p)
@@ -2058,7 +2090,7 @@ static inline int security_task_setscheduler (struct 
task_struct *p,
                                              int policy,
                                              struct sched_param *lp)
 {
-       return 0;
+       return cap_task_setscheduler(p, policy, lp);
 }
 
 static inline int security_task_getscheduler (struct task_struct *p)
@@ -2075,7 +2107,7 @@ static inline int security_task_kill (struct task_struct 
*p,
                                      struct siginfo *info, int sig,
                                      u32 secid)
 {
-       return 0;
+       return cap_task_kill(p, info, sig, secid);
 }
 
 static inline int security_task_wait (struct task_struct *p)
diff --git a/mm/filemap.c b/mm/filemap.c
index 4fb1546..79f24a9 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1627,12 +1627,18 @@ int __remove_suid(struct dentry *dentry, int kill)
 
 int remove_suid(struct dentry *dentry)
 {
-       int kill = should_remove_suid(dentry);
+       int killsuid = should_remove_suid(dentry);
+       int killpriv = security_inode_need_killpriv(dentry);
+       int error = 0;
 
-       if (unlikely(kill))
-               return __remove_suid(dentry, kill);
+       if (killpriv < 0)
+               return killpriv;
+       if (killpriv)
+               error = security_inode_killpriv(dentry);
+       if (!error && killsuid)
+               error = __remove_suid(dentry, killsuid);
 
-       return 0;
+       return error;
 }
 EXPORT_SYMBOL(remove_suid);
 
diff --git a/security/Kconfig b/security/Kconfig
index a94ee94..8086e61 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -80,6 +80,16 @@ config SECURITY_CAPABILITIES
          This enables the "default" Linux capabilities functionality.
          If you are unsure how to answer this question, answer Y.
 
+config SECURITY_FILE_CAPABILITIES
+       bool "File POSIX Capabilities (EXPERIMENTAL)"
+       depends on (SECURITY=n || SECURITY_CAPABILITIES!=n) && EXPERIMENTAL
+       default n
+       help
+         This enables filesystem capabilities, allowing you to give
+         binaries a subset of root's powers without using setuid 0.
+
+         If in doubt, answer N.
+
 config SECURITY_ROOTPLUG
        bool "Root Plug Support"
        depends on USB=y && SECURITY
diff --git a/security/capability.c b/security/capability.c
index fda6a14..9e99f36 100644
--- a/security/capability.c
+++ b/security/capability.c
@@ -37,7 +37,13 @@ static struct security_operations capability_ops = {
 
        .inode_setxattr =               cap_inode_setxattr,
        .inode_removexattr =            cap_inode_removexattr,
+       .inode_need_killpriv =          cap_inode_need_killpriv,
+       .inode_killpriv =               cap_inode_killpriv,
 
+       .task_kill =                    cap_task_kill,
+       .task_setscheduler =            cap_task_setscheduler,
+       .task_setioprio =               cap_task_setioprio,
+       .task_setnice =                 cap_task_setnice,
        .task_post_setuid =             cap_task_post_setuid,
        .task_reparent_to_init =        cap_task_reparent_to_init,
 
diff --git a/security/commoncap.c b/security/commoncap.c
index 0f8a2ce..afca6dd 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -22,6 +22,7 @@
 #include <linux/ptrace.h>
 #include <linux/xattr.h>
 #include <linux/hugetlb.h>
+#include <linux/mount.h>
 
 int cap_netlink_send(struct sock *sk, struct sk_buff *skb)
 {
@@ -108,14 +109,130 @@ void cap_capset_set (struct task_struct *target, 
kernel_cap_t *effective,
        target->cap_permitted = *permitted;
 }
 
+static inline void bprm_clear_caps(struct linux_binprm *bprm)
+{
+       cap_clear(bprm->cap_inheritable);
+       cap_clear(bprm->cap_permitted);
+       bprm->cap_effective = false;
+}
+
+#ifdef CONFIG_SECURITY_FILE_CAPABILITIES
+
+int cap_inode_need_killpriv(struct dentry *dentry)
+{
+       struct inode *inode = dentry->d_inode;
+       int error;
+
+       if (!inode->i_op || !inode->i_op->getxattr)
+              return 0;
+
+       error = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, NULL, 0);
+       if (error <= 0)
+               return 0;
+       return 1;
+}
+
+int cap_inode_killpriv(struct dentry *dentry)
+{
+       struct inode *inode = dentry->d_inode;
+
+       if (!inode->i_op || !inode->i_op->removexattr)
+              return 0;
+
+       return inode->i_op->removexattr(dentry, XATTR_NAME_CAPS);
+}
+
+static inline int cap_from_disk(__le32 *caps, struct linux_binprm *bprm,
+                               int size)
+{
+       __u32 magic_etc;
+
+       if (size != XATTR_CAPS_SZ)
+               return -EINVAL;
+
+       magic_etc = le32_to_cpu(caps[0]);
+
+       switch ((magic_etc & VFS_CAP_REVISION_MASK)) {
+       case VFS_CAP_REVISION:
+               if (magic_etc & VFS_CAP_FLAGS_EFFECTIVE)
+                       bprm->cap_effective = true;
+               else
+                       bprm->cap_effective = false;
+               bprm->cap_permitted = to_cap_t( le32_to_cpu(caps[1]) );
+               bprm->cap_inheritable = to_cap_t( le32_to_cpu(caps[2]) );
+               return 0;
+       default:
+               return -EINVAL;
+       }
+}
+
+/* Locate any VFS capabilities: */
+static int get_file_caps(struct linux_binprm *bprm)
+{
+       struct dentry *dentry;
+       int rc = 0;
+       __le32 v1caps[XATTR_CAPS_SZ];
+       struct inode *inode;
+
+       if (bprm->file->f_vfsmnt->mnt_flags & MNT_NOSUID) {
+               bprm_clear_caps(bprm);
+               return 0;
+       }
+
+       dentry = dget(bprm->file->f_dentry);
+       inode = dentry->d_inode;
+       if (!inode->i_op || !inode->i_op->getxattr)
+               goto out;
+
+       rc = inode->i_op->getxattr(dentry, XATTR_NAME_CAPS, &v1caps,
+                                                       XATTR_CAPS_SZ);
+       if (rc == -ENODATA || rc == -EOPNOTSUPP) {
+               /* no data, that's ok */
+               rc = 0;
+               goto out;
+       }
+       if (rc < 0)
+               goto out;
+
+       rc = cap_from_disk(v1caps, bprm, rc);
+       if (rc)
+               printk(KERN_NOTICE "%s: cap_from_disk returned %d for %s\n",
+                       __FUNCTION__, rc, bprm->filename);
+
+out:
+       dput(dentry);
+       if (rc)
+               bprm_clear_caps(bprm);
+
+       return rc;
+}
+
+#else
+int cap_inode_need_killpriv(struct dentry *dentry)
+{
+       return 0;
+}
+
+int cap_inode_killpriv(struct dentry *dentry)
+{
+       return 0;
+}
+
+static inline int get_file_caps(struct linux_binprm *bprm)
+{
+       bprm_clear_caps(bprm);
+       return 0;
+}
+#endif
+
 int cap_bprm_set_security (struct linux_binprm *bprm)
 {
-       /* Copied from fs/exec.c:prepare_binprm. */
+       int ret;
 
-       /* We don't have VFS support for capabilities yet */
-       cap_clear (bprm->cap_inheritable);
-       cap_clear (bprm->cap_permitted);
-       cap_clear (bprm->cap_effective);
+       ret = get_file_caps(bprm);
+       if (ret)
+               printk(KERN_NOTICE "%s: get_file_caps returned %d for %s\n",
+                       __FUNCTION__, ret, bprm->filename);
 
        /*  To support inheritance of root-permissions and suid-root
         *  executables under compatibility mode, we raise all three
@@ -131,9 +248,10 @@ int cap_bprm_set_security (struct linux_binprm *bprm)
                        cap_set_full (bprm->cap_permitted);
                }
                if (bprm->e_uid == 0)
-                       cap_set_full (bprm->cap_effective);
+                       bprm->cap_effective = true;
        }
-       return 0;
+
+       return ret;
 }
 
 void cap_bprm_apply_creds (struct linux_binprm *bprm, int unsafe)
@@ -149,6 +267,7 @@ void cap_bprm_apply_creds (struct linux_binprm *bprm, int 
unsafe)
        if (bprm->e_uid != current->uid || bprm->e_gid != current->gid ||
            !cap_issubset (new_permitted, current->cap_permitted)) {
                set_dumpable(current->mm, suid_dumpable);
+               current->pdeath_signal = 0;
 
                if (unsafe & ~LSM_UNSAFE_PTRACE_CAP) {
                        if (!capable(CAP_SETUID)) {
@@ -170,8 +289,8 @@ void cap_bprm_apply_creds (struct linux_binprm *bprm, int 
unsafe)
         * capability rules */
        if (!is_init(current)) {
                current->cap_permitted = new_permitted;
-               current->cap_effective =
-                   cap_intersect (new_permitted, bprm->cap_effective);
+               current->cap_effective = bprm->cap_effective ?
+                               new_permitted : 0;
        }
 
        /* AUD: Audit candidate if current->cap_effective is set */
@@ -181,11 +300,15 @@ void cap_bprm_apply_creds (struct linux_binprm *bprm, int 
unsafe)
 
 int cap_bprm_secureexec (struct linux_binprm *bprm)
 {
-       /* If/when this module is enhanced to incorporate capability
-          bits on files, the test below should be extended to also perform a 
-          test between the old and new capability sets.  For now,
-          it simply preserves the legacy decision algorithm used by
-          the old userland. */
+       if (current->uid != 0) {
+               if (bprm->cap_effective)
+                       return 1;
+               if (!cap_isclear(bprm->cap_permitted))
+                       return 1;
+               if (!cap_isclear(bprm->cap_inheritable))
+                       return 1;
+       }
+
        return (current->euid != current->uid ||
                current->egid != current->gid);
 }
@@ -193,7 +316,11 @@ int cap_bprm_secureexec (struct linux_binprm *bprm)
 int cap_inode_setxattr(struct dentry *dentry, char *name, void *value,
                       size_t size, int flags)
 {
-       if (!strncmp(name, XATTR_SECURITY_PREFIX,
+       if (!strcmp(name, XATTR_NAME_CAPS)) {
+               if (!capable(CAP_SETFCAP))
+                       return -EPERM;
+               return 0;
+       } else if (!strncmp(name, XATTR_SECURITY_PREFIX,
                     sizeof(XATTR_SECURITY_PREFIX) - 1)  &&
            !capable(CAP_SYS_ADMIN))
                return -EPERM;
@@ -202,7 +329,11 @@ int cap_inode_setxattr(struct dentry *dentry, char *name, 
void *value,
 
 int cap_inode_removexattr(struct dentry *dentry, char *name)
 {
-       if (!strncmp(name, XATTR_SECURITY_PREFIX,
+       if (!strcmp(name, XATTR_NAME_CAPS)) {
+               if (!capable(CAP_SETFCAP))
+                       return -EPERM;
+               return 0;
+       } else if (!strncmp(name, XATTR_SECURITY_PREFIX,
                     sizeof(XATTR_SECURITY_PREFIX) - 1)  &&
            !capable(CAP_SYS_ADMIN))
                return -EPERM;
@@ -299,6 +430,83 @@ int cap_task_post_setuid (uid_t old_ruid, uid_t old_euid, 
uid_t old_suid,
        return 0;
 }
 
+#ifdef CONFIG_SECURITY_FILE_CAPABILITIES
+/*
+ * Rationale: code calling task_setscheduler, task_setioprio, and
+ * task_setnice, assumes that
+ *   . if capable(cap_sys_nice), then those actions should be allowed
+ *   . if not capable(cap_sys_nice), but acting on your own processes,
+ *     then those actions should be allowed
+ * This is insufficient now since you can call code without suid, but
+ * yet with increased caps.
+ * So we check for increased caps on the target process.
+ */
+static inline int cap_safe_nice(struct task_struct *p)
+{
+       if (!cap_issubset(p->cap_permitted, current->cap_permitted) &&
+           !__capable(current, CAP_SYS_NICE))
+               return -EPERM;
+       return 0;
+}
+
+int cap_task_setscheduler (struct task_struct *p, int policy,
+                          struct sched_param *lp)
+{
+       return cap_safe_nice(p);
+}
+
+int cap_task_setioprio (struct task_struct *p, int ioprio)
+{
+       return cap_safe_nice(p);
+}
+
+int cap_task_setnice (struct task_struct *p, int nice)
+{
+       return cap_safe_nice(p);
+}
+
+int cap_task_kill(struct task_struct *p, struct siginfo *info,
+                               int sig, u32 secid)
+{
+       if (info != SEND_SIG_NOINFO && (is_si_special(info) || 
SI_FROMKERNEL(info)))
+               return 0;
+
+       if (secid)
+               /*
+                * Signal sent as a particular user.
+                * Capabilities are ignored.  May be wrong, but it's the
+                * only thing we can do at the moment.
+                * Used only by usb drivers?
+                */
+               return 0;
+       if (cap_issubset(p->cap_permitted, current->cap_permitted))
+               return 0;
+       if (capable(CAP_KILL))
+               return 0;
+
+       return -EPERM;
+}
+#else
+int cap_task_setscheduler (struct task_struct *p, int policy,
+                          struct sched_param *lp)
+{
+       return 0;
+}
+int cap_task_setioprio (struct task_struct *p, int ioprio)
+{
+       return 0;
+}
+int cap_task_setnice (struct task_struct *p, int nice)
+{
+       return 0;
+}
+int cap_task_kill(struct task_struct *p, struct siginfo *info,
+                               int sig, u32 secid)
+{
+       return 0;
+}
+#endif
+
 void cap_task_reparent_to_init (struct task_struct *p)
 {
        p->cap_effective = CAP_INIT_EFF_SET;
@@ -336,6 +544,10 @@ EXPORT_SYMBOL(cap_bprm_secureexec);
 EXPORT_SYMBOL(cap_inode_setxattr);
 EXPORT_SYMBOL(cap_inode_removexattr);
 EXPORT_SYMBOL(cap_task_post_setuid);
+EXPORT_SYMBOL(cap_task_kill);
+EXPORT_SYMBOL(cap_task_setscheduler);
+EXPORT_SYMBOL(cap_task_setioprio);
+EXPORT_SYMBOL(cap_task_setnice);
 EXPORT_SYMBOL(cap_task_reparent_to_init);
 EXPORT_SYMBOL(cap_syslog);
 EXPORT_SYMBOL(cap_vm_enough_memory);
diff --git a/security/dummy.c b/security/dummy.c
index 4129dcf..c77dec8 100644
--- a/security/dummy.c
+++ b/security/dummy.c
@@ -376,6 +376,16 @@ static int dummy_inode_removexattr (struct dentry *dentry, 
char *name)
        return 0;
 }
 
+static int dummy_inode_need_killpriv(struct dentry *dentry)
+{
+       return 0;
+}
+
+static int dummy_inode_killpriv(struct dentry *dentry)
+{
+       return 0;
+}
+
 static int dummy_inode_getsecurity(const struct inode *inode, const char 
*name, void *buffer, size_t size, int err)
 {
        return -EOPNOTSUPP;
@@ -1022,6 +1032,8 @@ void security_fixup_ops (struct security_operations *ops)
        set_to_dummy_if_null(ops, inode_getxattr);
        set_to_dummy_if_null(ops, inode_listxattr);
        set_to_dummy_if_null(ops, inode_removexattr);
+       set_to_dummy_if_null(ops, inode_need_killpriv);
+       set_to_dummy_if_null(ops, inode_killpriv);
        set_to_dummy_if_null(ops, inode_xattr_getsuffix);
        set_to_dummy_if_null(ops, inode_getsecurity);
        set_to_dummy_if_null(ops, inode_setsecurity);
diff --git a/security/security.c b/security/security.c
index 5b1c034..2e1b35d 100644
--- a/security/security.c
+++ b/security/security.c
@@ -518,6 +518,16 @@ int security_inode_removexattr(struct dentry *dentry, char 
*name)
        return security_ops->inode_removexattr(dentry, name);
 }
 
+int security_inode_need_killpriv(struct dentry *dentry)
+{
+       return security_ops->inode_need_killpriv(dentry);
+}
+
+int security_inode_killpriv(struct dentry *dentry)
+{
+       return security_ops->inode_killpriv(dentry);
+}
+
 const char *security_inode_xattr_getsuffix(void)
 {
        return security_ops->inode_xattr_getsuffix();
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 83a535b..221def6 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2297,6 +2297,25 @@ static int selinux_inode_getattr(struct vfsmount *mnt, 
struct dentry *dentry)
        return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);
 }
 
+static int selinux_inode_setotherxattr(struct dentry *dentry, char *name)
+{
+       if (!strncmp(name, XATTR_SECURITY_PREFIX,
+                    sizeof XATTR_SECURITY_PREFIX - 1)) {
+               if (!strcmp(name, XATTR_NAME_CAPS)) {
+                       if (!capable(CAP_SETFCAP))
+                               return -EPERM;
+               } else if (!capable(CAP_SYS_ADMIN)) {
+                       /* A different attribute in the security namespace.
+                          Restrict to administrator. */
+                       return -EPERM;
+               }
+       }
+
+       /* Not an attribute we recognize, so just check the
+          ordinary setattr permission. */
+       return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
+}
+
 static int selinux_inode_setxattr(struct dentry *dentry, char *name, void 
*value, size_t size, int flags)
 {
        struct task_security_struct *tsec = current->security;
@@ -2307,19 +2326,8 @@ static int selinux_inode_setxattr(struct dentry *dentry, 
char *name, void *value
        u32 newsid;
        int rc = 0;
 
-       if (strcmp(name, XATTR_NAME_SELINUX)) {
-               if (!strncmp(name, XATTR_SECURITY_PREFIX,
-                            sizeof XATTR_SECURITY_PREFIX - 1) &&
-                   !capable(CAP_SYS_ADMIN)) {
-                       /* A different attribute in the security namespace.
-                          Restrict to administrator. */
-                       return -EPERM;
-               }
-
-               /* Not an attribute we recognize, so just check the
-                  ordinary setattr permission. */
-               return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
-       }
+       if (strcmp(name, XATTR_NAME_SELINUX))
+               return selinux_inode_setotherxattr(dentry, name);
 
        sbsec = inode->i_sb->s_security;
        if (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)
@@ -2393,20 +2401,8 @@ static int selinux_inode_listxattr (struct dentry 
*dentry)
 
 static int selinux_inode_removexattr (struct dentry *dentry, char *name)
 {
-       if (strcmp(name, XATTR_NAME_SELINUX)) {
-               if (!strncmp(name, XATTR_SECURITY_PREFIX,
-                            sizeof XATTR_SECURITY_PREFIX - 1) &&
-                   !capable(CAP_SYS_ADMIN)) {
-                       /* A different attribute in the security namespace.
-                          Restrict to administrator. */
-                       return -EPERM;
-               }
-
-               /* Not an attribute we recognize, so just check the
-                  ordinary setattr permission. Might want a separate
-                  permission for removexattr. */
-               return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);
-       }
+       if (strcmp(name, XATTR_NAME_SELINUX))
+               return selinux_inode_setotherxattr(dentry, name);
 
        /* No one is allowed to remove a SELinux security label.
           You can change the label, but all data must be labeled. */
@@ -2464,6 +2460,16 @@ static int selinux_inode_listsecurity(struct inode 
*inode, char *buffer, size_t
        return len;
 }
 
+static int selinux_inode_need_killpriv(struct dentry *dentry)
+{
+       return secondary_ops->inode_need_killpriv(dentry);
+}
+
+static int selinux_inode_killpriv(struct dentry *dentry)
+{
+       return secondary_ops->inode_killpriv(dentry);
+}
+
 /* file security operations */
 
 static int selinux_revalidate_file_permission(struct file *file, int mask)
@@ -2882,6 +2888,12 @@ static int selinux_task_setnice(struct task_struct *p, 
int nice)
 
 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
 {
+       int rc;
+
+       rc = secondary_ops->task_setioprio(p, ioprio);
+       if (rc)
+               return rc;
+
        return task_has_perm(current, p, PROCESS__SETSCHED);
 }
 
@@ -2911,6 +2923,12 @@ static int selinux_task_setrlimit(unsigned int resource, 
struct rlimit *new_rlim
 
 static int selinux_task_setscheduler(struct task_struct *p, int policy, struct 
sched_param *lp)
 {
+       int rc;
+
+       rc = secondary_ops->task_setscheduler(p, policy, lp);
+       if (rc)
+               return rc;
+
        return task_has_perm(current, p, PROCESS__SETSCHED);
 }
 
@@ -4830,6 +4848,8 @@ static struct security_operations selinux_ops = {
        .inode_getsecurity =            selinux_inode_getsecurity,
        .inode_setsecurity =            selinux_inode_setsecurity,
        .inode_listsecurity =           selinux_inode_listsecurity,
+       .inode_need_killpriv =          selinux_inode_need_killpriv,
+       .inode_killpriv =               selinux_inode_killpriv,
 
        .file_permission =              selinux_file_permission,
        .file_alloc_security =          selinux_file_alloc_security,
-
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to