Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 88e67f3b authored by David Howells's avatar David Howells Committed by James Morris
Browse files

CRED: Make inode_has_perm() and file_has_perm() take a cred pointer 



Make inode_has_perm() and file_has_perm() take a cred pointer rather than a
task pointer.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Acked-by: default avatarJames Morris <jmorris@namei.org>
Acked-by: default avatarSerge Hallyn <serue@us.ibm.com>
Signed-off-by: default avatarJames Morris <jmorris@namei.org>
parent 6cc88bc4

security/selinux/hooks.c

+92 −48
Original line number Diff line number Diff line
@@ -172,17 +172,26 @@ static int cred_alloc_security(struct cred *cred) 
	return 0;

}



/*

 * get the security ID of a set of credentials

 */

static inline u32 cred_sid(const struct cred *cred)

{

	const struct task_security_struct *tsec;



	tsec = cred->security;

	return tsec->sid;

}



/*

 * get the security ID of a task

 */

static inline u32 task_sid(const struct task_struct *task)

{

	const struct task_security_struct *tsec;

	u32 sid;



	rcu_read_lock();

	tsec = __task_cred(task)->security;

	sid = tsec->sid;

	sid = cred_sid(__task_cred(task));

	rcu_read_unlock();

	return sid;

}
@@ -197,6 +206,8 @@ static inline u32 current_sid(void) 
	return tsec->sid;

}



/* Allocate and free functions for each kind of security blob. */



static int inode_alloc_security(struct inode *inode)

{

	struct inode_security_struct *isec;
@@ -1368,7 +1379,7 @@ static inline u32 signal_to_av(int sig) 
}



/*

 * Check permission betweeen a pair of tasks, e.g. signal checks,

 * Check permission between a pair of tasks, e.g. signal checks,

 * fork check, ptrace check, etc.

 * tsk1 is the actor and tsk2 is the target

 */
@@ -1437,7 +1448,7 @@ static int task_has_system(struct task_struct *tsk, 
/* Check whether a task has a particular permission to an inode.

   The 'adp' parameter is optional and allows other audit

   data to be passed (e.g. the dentry). */

static int inode_has_perm(struct task_struct *tsk,

static int inode_has_perm(const struct cred *cred,

			  struct inode *inode,

			  u32 perms,

			  struct avc_audit_data *adp)
@@ -1449,7 +1460,7 @@ static int inode_has_perm(struct task_struct *tsk, 
	if (unlikely(IS_PRIVATE(inode)))

		return 0;



	sid = task_sid(tsk);

	sid = cred_sid(cred);

	isec = inode->i_security;



	if (!adp) {
@@ -1464,17 +1475,18 @@ static int inode_has_perm(struct task_struct *tsk, 
/* Same as inode_has_perm, but pass explicit audit data containing

   the dentry to help the auditing code to more easily generate the

   pathname if needed. */

static inline int dentry_has_perm(struct task_struct *tsk,

static inline int dentry_has_perm(const struct cred *cred,

				  struct vfsmount *mnt,

				  struct dentry *dentry,

				  u32 av)

{

	struct inode *inode = dentry->d_inode;

	struct avc_audit_data ad;



	AVC_AUDIT_DATA_INIT(&ad, FS);

	ad.u.fs.path.mnt = mnt;

	ad.u.fs.path.dentry = dentry;

	return inode_has_perm(tsk, inode, av, &ad);

	return inode_has_perm(cred, inode, av, &ad);

}



/* Check whether a task can use an open file descriptor to
@@ -1485,14 +1497,14 @@ static inline int dentry_has_perm(struct task_struct *tsk, 
   has the same SID as the process.  If av is zero, then

   access to the file is not checked, e.g. for cases

   where only the descriptor is affected like seek. */

static int file_has_perm(struct task_struct *tsk,

static int file_has_perm(const struct cred *cred,

			 struct file *file,

			 u32 av)

{

	struct file_security_struct *fsec = file->f_security;

	struct inode *inode = file->f_path.dentry->d_inode;

	struct avc_audit_data ad;

	u32 sid = task_sid(tsk);

	u32 sid = cred_sid(cred);

	int rc;



	AVC_AUDIT_DATA_INIT(&ad, FS);
@@ -1504,14 +1516,16 @@ static int file_has_perm(struct task_struct *tsk, 
				  FD__USE,

				  &ad);

		if (rc)

			return rc;

			goto out;

	}



	/* av is zero if only checking access to the descriptor. */

	rc = 0;

	if (av)

		return inode_has_perm(tsk, inode, av, &ad);

		rc = inode_has_perm(cred, inode, av, &ad);



	return 0;

out:

	return rc;

}



/* Check whether a task can create a file. */
@@ -1670,13 +1684,13 @@ static inline int may_rename(struct inode *old_dir, 
}



/* Check whether a task can perform a filesystem operation. */

static int superblock_has_perm(struct task_struct *tsk,

static int superblock_has_perm(const struct cred *cred,

			       struct super_block *sb,

			       u32 perms,

			       struct avc_audit_data *ad)

{

	struct superblock_security_struct *sbsec;

	u32 sid = task_sid(tsk);

	u32 sid = cred_sid(cred);



	sbsec = sb->s_security;

	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
@@ -1919,6 +1933,7 @@ static int selinux_sysctl(ctl_table *table, int op) 


static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)

{

	const struct cred *cred = current_cred();

	int rc = 0;



	if (!sb)
@@ -1930,14 +1945,12 @@ static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 
	case Q_QUOTAOFF:

	case Q_SETINFO:

	case Q_SETQUOTA:

		rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAMOD,

					 NULL);

		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);

		break;

	case Q_GETFMT:

	case Q_GETINFO:

	case Q_GETQUOTA:

		rc = superblock_has_perm(current, sb, FILESYSTEM__QUOTAGET,

					 NULL);

		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);

		break;

	default:

		rc = 0;  /* let the kernel handle invalid cmds */
@@ -1948,7 +1961,9 @@ static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb) 


static int selinux_quota_on(struct dentry *dentry)

{

	return dentry_has_perm(current, NULL, dentry, FILE__QUOTAON);

	const struct cred *cred = current_cred();



	return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);

}



static int selinux_syslog(int type)
@@ -2137,6 +2152,7 @@ extern struct dentry *selinux_null; 
/* Derived from fs/exec.c:flush_old_files. */

static inline void flush_unauthorized_files(struct files_struct *files)

{

	const struct cred *cred = current_cred();

	struct avc_audit_data ad;

	struct file *file, *devnull = NULL;

	struct tty_struct *tty;
@@ -2157,7 +2173,7 @@ static inline void flush_unauthorized_files(struct files_struct *files) 
			   interested in the inode-based check here. */

			file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);

			inode = file->f_path.dentry->d_inode;

			if (inode_has_perm(current, inode,

			if (inode_has_perm(cred, inode,

					   FILE__READ | FILE__WRITE, NULL)) {

				drop_tty = 1;

			}
@@ -2192,7 +2208,7 @@ static inline void flush_unauthorized_files(struct files_struct *files) 
				file = fget(i);

				if (!file)

					continue;

				if (file_has_perm(current,

				if (file_has_perm(cred,

						  file,

						  file_to_av(file))) {

					sys_close(i);
@@ -2465,6 +2481,7 @@ static int selinux_sb_copy_data(char *orig, char *copy) 


static int selinux_sb_kern_mount(struct super_block *sb, void *data)

{

	const struct cred *cred = current_cred();

	struct avc_audit_data ad;

	int rc;
@@ -2474,16 +2491,17 @@ static int selinux_sb_kern_mount(struct super_block *sb, void *data) 


	AVC_AUDIT_DATA_INIT(&ad, FS);

	ad.u.fs.path.dentry = sb->s_root;

	return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);

	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);

}



static int selinux_sb_statfs(struct dentry *dentry)

{

	const struct cred *cred = current_cred();

	struct avc_audit_data ad;



	AVC_AUDIT_DATA_INIT(&ad, FS);

	ad.u.fs.path.dentry = dentry->d_sb->s_root;

	return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);

	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);

}



static int selinux_mount(char *dev_name,
@@ -2492,6 +2510,7 @@ static int selinux_mount(char *dev_name, 
			 unsigned long flags,

			 void *data)

{

	const struct cred *cred = current_cred();

	int rc;



	rc = secondary_ops->sb_mount(dev_name, path, type, flags, data);
@@ -2499,22 +2518,23 @@ static int selinux_mount(char *dev_name, 
		return rc;



	if (flags & MS_REMOUNT)

		return superblock_has_perm(current, path->mnt->mnt_sb,

		return superblock_has_perm(cred, path->mnt->mnt_sb,

					   FILESYSTEM__REMOUNT, NULL);

	else

		return dentry_has_perm(current, path->mnt, path->dentry,

		return dentry_has_perm(cred, path->mnt, path->dentry,

				       FILE__MOUNTON);

}



static int selinux_umount(struct vfsmount *mnt, int flags)

{

	const struct cred *cred = current_cred();

	int rc;



	rc = secondary_ops->sb_umount(mnt, flags);

	if (rc)

		return rc;



	return superblock_has_perm(current, mnt->mnt_sb,

	return superblock_has_perm(cred, mnt->mnt_sb,

				   FILESYSTEM__UNMOUNT, NULL);

}
@@ -2652,21 +2672,25 @@ static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dent 


static int selinux_inode_readlink(struct dentry *dentry)

{

	return dentry_has_perm(current, NULL, dentry, FILE__READ);

	const struct cred *cred = current_cred();



	return dentry_has_perm(cred, NULL, dentry, FILE__READ);

}



static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)

{

	const struct cred *cred = current_cred();

	int rc;



	rc = secondary_ops->inode_follow_link(dentry, nameidata);

	if (rc)

		return rc;

	return dentry_has_perm(current, NULL, dentry, FILE__READ);

	return dentry_has_perm(cred, NULL, dentry, FILE__READ);

}



static int selinux_inode_permission(struct inode *inode, int mask)

{

	const struct cred *cred = current_cred();

	int rc;



	rc = secondary_ops->inode_permission(inode, mask);
@@ -2678,12 +2702,13 @@ static int selinux_inode_permission(struct inode *inode, int mask) 
		return 0;

	}



	return inode_has_perm(current, inode,

	return inode_has_perm(cred, inode,

			      file_mask_to_av(inode->i_mode, mask), NULL);

}



static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)

{

	const struct cred *cred = current_cred();

	int rc;



	rc = secondary_ops->inode_setattr(dentry, iattr);
@@ -2695,18 +2720,22 @@ static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr) 


	if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |

			       ATTR_ATIME_SET | ATTR_MTIME_SET))

		return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);

		return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);



	return dentry_has_perm(current, NULL, dentry, FILE__WRITE);

	return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);

}



static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)

{

	return dentry_has_perm(current, mnt, dentry, FILE__GETATTR);

	const struct cred *cred = current_cred();



	return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);

}



static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)

{

	const struct cred *cred = current_cred();



	if (!strncmp(name, XATTR_SECURITY_PREFIX,

		     sizeof XATTR_SECURITY_PREFIX - 1)) {

		if (!strcmp(name, XATTR_NAME_CAPS)) {
@@ -2721,7 +2750,7 @@ static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name) 


	/* Not an attribute we recognize, so just check the

	   ordinary setattr permission. */

	return dentry_has_perm(current, NULL, dentry, FILE__SETATTR);

	return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);

}



static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
@@ -2806,12 +2835,16 @@ static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name, 


static int selinux_inode_getxattr(struct dentry *dentry, const char *name)

{

	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);

	const struct cred *cred = current_cred();



	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);

}



static int selinux_inode_listxattr(struct dentry *dentry)

{

	return dentry_has_perm(current, NULL, dentry, FILE__GETATTR);

	const struct cred *cred = current_cred();



	return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);

}



static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
@@ -2915,6 +2948,7 @@ static void selinux_inode_getsecid(const struct inode *inode, u32 *secid) 


static int selinux_revalidate_file_permission(struct file *file, int mask)

{

	const struct cred *cred = current_cred();

	int rc;

	struct inode *inode = file->f_path.dentry->d_inode;
@@ -2927,7 +2961,7 @@ static int selinux_revalidate_file_permission(struct file *file, int mask) 
	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))

		mask |= MAY_APPEND;



	rc = file_has_perm(current, file,

	rc = file_has_perm(cred, file,

			   file_mask_to_av(inode->i_mode, mask));

	if (rc)

		return rc;
@@ -2967,6 +3001,7 @@ static void selinux_file_free_security(struct file *file) 
static int selinux_file_ioctl(struct file *file, unsigned int cmd,

			      unsigned long arg)

{

	const struct cred *cred = current_cred();

	u32 av = 0;



	if (_IOC_DIR(cmd) & _IOC_WRITE)
@@ -2976,11 +3011,13 @@ static int selinux_file_ioctl(struct file *file, unsigned int cmd, 
	if (!av)

		av = FILE__IOCTL;



	return file_has_perm(current, file, av);

	return file_has_perm(cred, file, av);

}



static int file_map_prot_check(struct file *file, unsigned long prot, int shared)

{

	const struct cred *cred = current_cred();



#ifndef CONFIG_PPC32

	if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {

		/*
@@ -3005,7 +3042,7 @@ static int file_map_prot_check(struct file *file, unsigned long prot, int shared 
		if (prot & PROT_EXEC)

			av |= FILE__EXECUTE;



		return file_has_perm(current, file, av);

		return file_has_perm(cred, file, av);

	}

	return 0;

}
@@ -3034,6 +3071,7 @@ static int selinux_file_mprotect(struct vm_area_struct *vma, 
				 unsigned long reqprot,

				 unsigned long prot)

{

	const struct cred *cred = current_cred();

	int rc;



	rc = secondary_ops->file_mprotect(vma, reqprot, prot);
@@ -3062,7 +3100,7 @@ static int selinux_file_mprotect(struct vm_area_struct *vma, 
			 * modified content.  This typically should only

			 * occur for text relocations.

			 */

			rc = file_has_perm(current, vma->vm_file,

			rc = file_has_perm(cred, vma->vm_file,

					   FILE__EXECMOD);

		}

		if (rc)
@@ -3075,12 +3113,15 @@ static int selinux_file_mprotect(struct vm_area_struct *vma, 


static int selinux_file_lock(struct file *file, unsigned int cmd)

{

	return file_has_perm(current, file, FILE__LOCK);

	const struct cred *cred = current_cred();



	return file_has_perm(cred, file, FILE__LOCK);

}



static int selinux_file_fcntl(struct file *file, unsigned int cmd,

			      unsigned long arg)

{

	const struct cred *cred = current_cred();

	int err = 0;



	switch (cmd) {
@@ -3091,7 +3132,7 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd, 
		}



		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {

			err = file_has_perm(current, file, FILE__WRITE);

			err = file_has_perm(cred, file, FILE__WRITE);

			break;

		}

		/* fall through */
@@ -3101,7 +3142,7 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd, 
	case F_GETOWN:

	case F_GETSIG:

		/* Just check FD__USE permission */

		err = file_has_perm(current, file, 0);

		err = file_has_perm(cred, file, 0);

		break;

	case F_GETLK:

	case F_SETLK:
@@ -3115,7 +3156,7 @@ static int selinux_file_fcntl(struct file *file, unsigned int cmd, 
			err = -EINVAL;

			break;

		}

		err = file_has_perm(current, file, FILE__LOCK);

		err = file_has_perm(cred, file, FILE__LOCK);

		break;

	}
@@ -3156,11 +3197,14 @@ static int selinux_file_send_sigiotask(struct task_struct *tsk, 


static int selinux_file_receive(struct file *file)

{

	return file_has_perm(current, file, file_to_av(file));

	const struct cred *cred = current_cred();



	return file_has_perm(cred, file, file_to_av(file));

}



static int selinux_dentry_open(struct file *file)

{

	const struct cred *cred = current_cred();

	struct file_security_struct *fsec;

	struct inode *inode;

	struct inode_security_struct *isec;
@@ -3184,7 +3228,7 @@ static int selinux_dentry_open(struct file *file) 
	 * new inode label or new policy.

	 * This check is not redundant - do not remove.

	 */

	return inode_has_perm(current, inode, open_file_to_av(file), NULL);

	return inode_has_perm(cred, inode, open_file_to_av(file), NULL);

}



/* task security operations */