aboutsummaryrefslogtreecommitdiffstats
path: root/security/selinux/hooks.c
diff options
context:
space:
mode:
Diffstat (limited to 'security/selinux/hooks.c')
-rw-r--r--security/selinux/hooks.c116
1 files changed, 99 insertions, 17 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 5c6f2cd2d095..c956390a9136 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -81,6 +81,7 @@
#include <linux/syslog.h>
#include <linux/user_namespace.h>
#include <linux/export.h>
+#include <linux/security.h>
#include <linux/msg.h>
#include <linux/shm.h>
@@ -284,13 +285,14 @@ static void superblock_free_security(struct super_block *sb)
/* The file system's label must be initialized prior to use. */
-static const char *labeling_behaviors[6] = {
+static const char *labeling_behaviors[7] = {
"uses xattr",
"uses transition SIDs",
"uses task SIDs",
"uses genfs_contexts",
"not configured for labeling",
"uses mountpoint labeling",
+ "uses native labeling",
};
static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
@@ -552,7 +554,9 @@ static int bad_option(struct superblock_security_struct *sbsec, char flag,
* labeling information.
*/
static int selinux_set_mnt_opts(struct super_block *sb,
- struct security_mnt_opts *opts)
+ struct security_mnt_opts *opts,
+ unsigned long kern_flags,
+ unsigned long *set_kern_flags)
{
const struct cred *cred = current_cred();
int rc = 0, i;
@@ -580,6 +584,12 @@ static int selinux_set_mnt_opts(struct super_block *sb,
"before the security server is initialized\n");
goto out;
}
+ if (kern_flags && !set_kern_flags) {
+ /* Specifying internal flags without providing a place to
+ * place the results is not allowed */
+ rc = -EINVAL;
+ goto out;
+ }
/*
* Binary mount data FS will come through this function twice. Once
@@ -670,14 +680,21 @@ static int selinux_set_mnt_opts(struct super_block *sb,
if (strcmp(sb->s_type->name, "proc") == 0)
sbsec->flags |= SE_SBPROC;
- /* Determine the labeling behavior to use for this filesystem type. */
- rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
- if (rc) {
- printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
- __func__, sb->s_type->name, rc);
- goto out;
+ if (!sbsec->behavior) {
+ /*
+ * Determine the labeling behavior to use for this
+ * filesystem type.
+ */
+ rc = security_fs_use((sbsec->flags & SE_SBPROC) ?
+ "proc" : sb->s_type->name,
+ &sbsec->behavior, &sbsec->sid);
+ if (rc) {
+ printk(KERN_WARNING
+ "%s: security_fs_use(%s) returned %d\n",
+ __func__, sb->s_type->name, rc);
+ goto out;
+ }
}
-
/* sets the context of the superblock for the fs being mounted. */
if (fscontext_sid) {
rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
@@ -692,6 +709,11 @@ static int selinux_set_mnt_opts(struct super_block *sb,
* sets the label used on all file below the mountpoint, and will set
* the superblock context if not already set.
*/
+ if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
+ sbsec->behavior = SECURITY_FS_USE_NATIVE;
+ *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
+ }
+
if (context_sid) {
if (!fscontext_sid) {
rc = may_context_mount_sb_relabel(context_sid, sbsec,
@@ -723,7 +745,8 @@ static int selinux_set_mnt_opts(struct super_block *sb,
}
if (defcontext_sid) {
- if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
+ if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
+ sbsec->behavior != SECURITY_FS_USE_NATIVE) {
rc = -EINVAL;
printk(KERN_WARNING "SELinux: defcontext option is "
"invalid for this filesystem type\n");
@@ -980,7 +1003,7 @@ static int superblock_doinit(struct super_block *sb, void *data)
goto out_err;
out:
- rc = selinux_set_mnt_opts(sb, &opts);
+ rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
out_err:
security_free_mnt_opts(&opts);
@@ -1222,6 +1245,8 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
}
switch (sbsec->behavior) {
+ case SECURITY_FS_USE_NATIVE:
+ break;
case SECURITY_FS_USE_XATTR:
if (!inode->i_op->getxattr) {
isec->sid = sbsec->def_sid;
@@ -1547,6 +1572,18 @@ static inline int path_has_perm(const struct cred *cred,
return inode_has_perm(cred, inode, av, &ad, 0);
}
+/* Same as path_has_perm, but uses the inode from the file struct. */
+static inline int file_path_has_perm(const struct cred *cred,
+ struct file *file,
+ u32 av)
+{
+ struct common_audit_data ad;
+
+ ad.type = LSM_AUDIT_DATA_PATH;
+ ad.u.path = file->f_path;
+ return inode_has_perm(cred, file_inode(file), av, &ad, 0);
+}
+
/* Check whether a task can use an open file descriptor to
access an inode in a given way. Check access to the
descriptor itself, and then use dentry_has_perm to
@@ -2141,14 +2178,14 @@ static inline void flush_unauthorized_files(const struct cred *cred,
struct tty_file_private *file_priv;
/* Revalidate access to controlling tty.
- Use path_has_perm on the tty path directly rather
- than using file_has_perm, as this particular open
- file may belong to another process and we are only
- interested in the inode-based check here. */
+ Use file_path_has_perm on the tty path directly
+ rather than using file_has_perm, as this particular
+ open file may belong to another process and we are
+ only interested in the inode-based check here. */
file_priv = list_first_entry(&tty->tty_files,
struct tty_file_private, list);
file = file_priv->file;
- if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE))
+ if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
drop_tty = 1;
}
spin_unlock(&tty_files_lock);
@@ -2515,6 +2552,40 @@ static void selinux_inode_free_security(struct inode *inode)
inode_free_security(inode);
}
+static int selinux_dentry_init_security(struct dentry *dentry, int mode,
+ struct qstr *name, void **ctx,
+ u32 *ctxlen)
+{
+ const struct cred *cred = current_cred();
+ struct task_security_struct *tsec;
+ struct inode_security_struct *dsec;
+ struct superblock_security_struct *sbsec;
+ struct inode *dir = dentry->d_parent->d_inode;
+ u32 newsid;
+ int rc;
+
+ tsec = cred->security;
+ dsec = dir->i_security;
+ sbsec = dir->i_sb->s_security;
+
+ if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
+ newsid = tsec->create_sid;
+ } else {
+ rc = security_transition_sid(tsec->sid, dsec->sid,
+ inode_mode_to_security_class(mode),
+ name,
+ &newsid);
+ if (rc) {
+ printk(KERN_WARNING
+ "%s: security_transition_sid failed, rc=%d\n",
+ __func__, -rc);
+ return rc;
+ }
+ }
+
+ return security_sid_to_context(newsid, (char **)ctx, ctxlen);
+}
+
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
const struct qstr *qstr, char **name,
void **value, size_t *len)
@@ -2849,7 +2920,10 @@ static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
return;
}
+ isec->sclass = inode_mode_to_security_class(inode->i_mode);
isec->sid = newsid;
+ isec->initialized = 1;
+
return;
}
@@ -2937,6 +3011,7 @@ static int selinux_inode_setsecurity(struct inode *inode, const char *name,
if (rc)
return rc;
+ isec->sclass = inode_mode_to_security_class(inode->i_mode);
isec->sid = newsid;
isec->initialized = 1;
return 0;
@@ -3259,7 +3334,7 @@ static int selinux_file_open(struct file *file, const struct cred *cred)
* new inode label or new policy.
* This check is not redundant - do not remove.
*/
- return path_has_perm(cred, &file->f_path, open_file_to_av(file));
+ return file_path_has_perm(cred, file, open_file_to_av(file));
}
/* task security operations */
@@ -5420,6 +5495,11 @@ abort_change:
return error;
}
+static int selinux_ismaclabel(const char *name)
+{
+ return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
+}
+
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
return security_sid_to_context(secid, secdata, seclen);
@@ -5562,6 +5642,7 @@ static struct security_operations selinux_ops = {
.sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
.sb_parse_opts_str = selinux_parse_opts_str,
+ .dentry_init_security = selinux_dentry_init_security,
.inode_alloc_security = selinux_inode_alloc_security,
.inode_free_security = selinux_inode_free_security,
@@ -5657,6 +5738,7 @@ static struct security_operations selinux_ops = {
.getprocattr = selinux_getprocattr,
.setprocattr = selinux_setprocattr,
+ .ismaclabel = selinux_ismaclabel,
.secid_to_secctx = selinux_secid_to_secctx,
.secctx_to_secid = selinux_secctx_to_secid,
.release_secctx = selinux_release_secctx,
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.