Commit 0d4d717f authored by Eric W. Biederman's avatar Eric W. Biederman
Browse files

vfs: Verify acls are valid within superblock's s_user_ns. 



Update posix_acl_valid to verify that an acl is within a user namespace.

Update the callers of posix_acl_valid to pass in an appropriate
user namespace.  For posix_acl_xattr_set and v9fs_xattr_set_acl pass in
inode->i_sb->s_user_ns to posix_acl_valid.  For md_unpack_acl pass in
&init_user_ns as no inode or superblock is in sight.

Acked-by: default avatarSeth Forshee <seth.forshee@canonical.com>
Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
parent 37b11804

drivers/staging/lustre/lustre/mdc/mdc_request.c

+1 −1
Original line number Diff line number Diff line
@@ -434,7 +434,7 @@ static int mdc_unpack_acl(struct ptlrpc_request *req, struct lustre_md *md) 
		return rc;

	}



	rc = posix_acl_valid(acl);

	rc = posix_acl_valid(&init_user_ns, acl);

	if (rc) {

		CERROR("validate acl: %d\n", rc);

		posix_acl_release(acl);

fs/9p/acl.c

+1 −1
Original line number Diff line number Diff line
@@ -266,7 +266,7 @@ static int v9fs_xattr_set_acl(const struct xattr_handler *handler, 
		if (IS_ERR(acl))

			return PTR_ERR(acl);

		else if (acl) {

			retval = posix_acl_valid(acl);

			retval = posix_acl_valid(inode->i_sb->s_user_ns, acl);

			if (retval)

				goto err_out;

		}

fs/posix_acl.c

+4 −4
Original line number Diff line number Diff line
@@ -205,7 +205,7 @@ posix_acl_clone(const struct posix_acl *acl, gfp_t flags) 
 * Check if an acl is valid. Returns 0 if it is, or -E... otherwise.

 */

int

posix_acl_valid(const struct posix_acl *acl)

posix_acl_valid(struct user_namespace *user_ns, const struct posix_acl *acl)

{

	const struct posix_acl_entry *pa, *pe;

	int state = ACL_USER_OBJ;
@@ -225,7 +225,7 @@ posix_acl_valid(const struct posix_acl *acl) 
			case ACL_USER:

				if (state != ACL_USER)

					return -EINVAL;

				if (!uid_valid(pa->e_uid))

				if (!kuid_has_mapping(user_ns, pa->e_uid))

					return -EINVAL;

				needs_mask = 1;

				break;
@@ -240,7 +240,7 @@ posix_acl_valid(const struct posix_acl *acl) 
			case ACL_GROUP:

				if (state != ACL_GROUP)

					return -EINVAL;

				if (!gid_valid(pa->e_gid))

				if (!kgid_has_mapping(user_ns, pa->e_gid))

					return -EINVAL;

				needs_mask = 1;

				break;
@@ -845,7 +845,7 @@ posix_acl_xattr_set(const struct xattr_handler *handler, 
			return PTR_ERR(acl);



		if (acl) {

			ret = posix_acl_valid(acl);

			ret = posix_acl_valid(inode->i_sb->s_user_ns, acl);

			if (ret)

				goto out;

		}

include/linux/posix_acl.h

+1 −1
Original line number Diff line number Diff line
@@ -81,7 +81,7 @@ posix_acl_release(struct posix_acl *acl) 


extern void posix_acl_init(struct posix_acl *, int);

extern struct posix_acl *posix_acl_alloc(int, gfp_t);

extern int posix_acl_valid(const struct posix_acl *);

extern int posix_acl_valid(struct user_namespace *, const struct posix_acl *);

extern int posix_acl_permission(struct inode *, const struct posix_acl *, int);

extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t);

extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *);

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