summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--fs/attr.c9
-rw-r--r--fs/nfsd/vfs.c4
-rw-r--r--fs/open.c3
-rw-r--r--fs/splice.c13
-rw-r--r--include/linux/binfmts.h3
-rw-r--r--include/linux/capability.h48
-rw-r--r--include/linux/fs.h1
-rw-r--r--include/linux/security.h40
-rw-r--r--mm/filemap.c14
-rw-r--r--security/Kconfig10
-rw-r--r--security/capability.c6
-rw-r--r--security/commoncap.c244
-rw-r--r--security/dummy.c12
-rw-r--r--security/security.c10
-rw-r--r--security/selinux/hooks.c74
15 files changed, 418 insertions, 73 deletions
diff --git a/fs/attr.c b/fs/attr.c
index f8dfc2269d8..ae58bd3f875 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 1d72f993b66..819545d2167 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 cdbb94a9efc..75385144df7 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 59a941d404d..6bdcb6107bc 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 3a6512f8ec9..b7fc55ec8d4 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 2dfa5855593..8961e7fb755 100644
--- a/include/linux/capability.h
+++ b/include/linux/capability.h
@@ -1,14 +1,14 @@
/*
* This is <linux/capability.h>
*
- * Andrew G. Morgan <morgan@transmeta.com>
+ * Andrew G. Morgan <morgan@kernel.org>
* Alexander Kjeldaas <astor@guardian.no>
* 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 365586a4c4d..e3fc5dbb224 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 a300a3f2fe6..df591d289ec 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 4fb1546bbad..79f24a969cb 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 a94ee94cf49..8086e61058e 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 fda6a14cb24..9e99f36a8b5 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 0f8a2ce3f3a..afca6dd4ae6 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 4129dcf3dae..c77dec82238 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 5b1c034815a..2e1b35dd255 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 83a535b7bc6..221def6a0b1 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,
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-16 11:19:32 +0000