Merge branch 'linux-linaro-lsk' into linux-linaro-lsk-android

12 files changed, 171 insertions, 146 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 0f81d67cdc8..8dedf401967 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -3299,6 +3299,9 @@ static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
 
 	switch (p->cmd) {
 	case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
+		if (root->fs_info->sb->s_flags & MS_RDONLY)
+			return -EROFS;
+
 		if (atomic_xchg(
 			&root->fs_info->mutually_exclusive_operation_running,
 			1)) {
diff --git a/fs/ceph/ioctl.c b/fs/ceph/ioctl.c
index e0b4ef31d3c..a5ce62eb780 100644
--- a/fs/ceph/ioctl.c
+++ b/fs/ceph/ioctl.c
@@ -196,8 +196,10 @@ static long ceph_ioctl_get_dataloc(struct file *file, void __user *arg)
 	r = ceph_calc_file_object_mapping(&ci->i_layout, dl.file_offset, len,
 					  &dl.object_no, &dl.object_offset,
 					  &olen);
-	if (r < 0)
+	if (r < 0) {
+		up_read(&osdc->map_sem);
 		return -EIO;
+	}
 	dl.file_offset -= dl.object_offset;
 	dl.object_size = ceph_file_layout_object_size(ci->i_layout);
 	dl.block_size = ceph_file_layout_su(ci->i_layout);
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index d6a5c5ac737..d05a3007202 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -377,6 +377,7 @@ cifs_reconnect(struct TCP_Server_Info *server)
 		try_to_freeze();
 
 		/* we should try only the port we connected to before */
+		mutex_lock(&server->srv_mutex);
 		rc = generic_ip_connect(server);
 		if (rc) {
 			cifs_dbg(FYI, "reconnect error %d\n", rc);
@@ -388,6 +389,7 @@ cifs_reconnect(struct TCP_Server_Info *server)
 				server->tcpStatus = CifsNeedNegotiate;
 			spin_unlock(&GlobalMid_Lock);
 		}
+		mutex_unlock(&server->srv_mutex);
 	} while (server->tcpStatus == CifsNeedReconnect);
 
 	return rc;
diff --git a/fs/cifs/smb2misc.c b/fs/cifs/smb2misc.c
index 10383d8c015..4f791e0e98d 100644
--- a/fs/cifs/smb2misc.c
+++ b/fs/cifs/smb2misc.c
@@ -413,96 +413,108 @@ cifs_ses_oplock_break(struct work_struct *work)
 }
 
 static bool
-smb2_is_valid_lease_break(char *buffer, struct TCP_Server_Info *server)
+smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp,
+		    struct smb2_lease_break_work *lw)
 {
-	struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
-	struct list_head *tmp, *tmp1, *tmp2;
-	struct cifs_ses *ses;
-	struct cifs_tcon *tcon;
-	struct cifsInodeInfo *cinode;
+	bool found;
+	__u8 lease_state;
+	struct list_head *tmp;
 	struct cifsFileInfo *cfile;
 	struct cifs_pending_open *open;
-	struct smb2_lease_break_work *lw;
-	bool found;
+	struct cifsInodeInfo *cinode;
 	int ack_req = le32_to_cpu(rsp->Flags &
 				  SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 
-	lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
-	if (!lw)
-		return false;
+	lease_state = smb2_map_lease_to_oplock(rsp->NewLeaseState);
 
-	INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
-	lw->lease_state = rsp->NewLeaseState;
+	list_for_each(tmp, &tcon->openFileList) {
+		cfile = list_entry(tmp, struct cifsFileInfo, tlist);
+		cinode = CIFS_I(cfile->dentry->d_inode);
 
-	cifs_dbg(FYI, "Checking for lease break\n");
+		if (memcmp(cinode->lease_key, rsp->LeaseKey,
+							SMB2_LEASE_KEY_SIZE))
+			continue;
 
-	/* look up tcon based on tid & uid */
-	spin_lock(&cifs_tcp_ses_lock);
-	list_for_each(tmp, &server->smb_ses_list) {
-		ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
+		cifs_dbg(FYI, "found in the open list\n");
+		cifs_dbg(FYI, "lease key match, lease break 0x%d\n",
+			 le32_to_cpu(rsp->NewLeaseState));
 
-		spin_lock(&cifs_file_list_lock);
-		list_for_each(tmp1, &ses->tcon_list) {
-			tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
+		smb2_set_oplock_level(cinode, lease_state);
 
-			cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);
-			list_for_each(tmp2, &tcon->openFileList) {
-				cfile = list_entry(tmp2, struct cifsFileInfo,
-						   tlist);
-				cinode = CIFS_I(cfile->dentry->d_inode);
+		if (ack_req)
+			cfile->oplock_break_cancelled = false;
+		else
+			cfile->oplock_break_cancelled = true;
 
-				if (memcmp(cinode->lease_key, rsp->LeaseKey,
-					   SMB2_LEASE_KEY_SIZE))
-					continue;
+		queue_work(cifsiod_wq, &cfile->oplock_break);
+		kfree(lw);
+		return true;
+	}
 
-				cifs_dbg(FYI, "found in the open list\n");
-				cifs_dbg(FYI, "lease key match, lease break 0x%d\n",
-					 le32_to_cpu(rsp->NewLeaseState));
+	found = false;
+	list_for_each_entry(open, &tcon->pending_opens, olist) {
+		if (memcmp(open->lease_key, rsp->LeaseKey,
+			   SMB2_LEASE_KEY_SIZE))
+			continue;
+
+		if (!found && ack_req) {
+			found = true;
+			memcpy(lw->lease_key, open->lease_key,
+			       SMB2_LEASE_KEY_SIZE);
+			lw->tlink = cifs_get_tlink(open->tlink);
+			queue_work(cifsiod_wq, &lw->lease_break);
+		}
 
-				smb2_set_oplock_level(cinode,
-				  smb2_map_lease_to_oplock(rsp->NewLeaseState));
+		cifs_dbg(FYI, "found in the pending open list\n");
+		cifs_dbg(FYI, "lease key match, lease break 0x%d\n",
+			 le32_to_cpu(rsp->NewLeaseState));
 
-				if (ack_req)
-					cfile->oplock_break_cancelled = false;
-				else
-					cfile->oplock_break_cancelled = true;
+		open->oplock = lease_state;
+	}
+	return found;
+}
 
-				queue_work(cifsiod_wq, &cfile->oplock_break);
+static bool
+smb2_is_valid_lease_break(char *buffer)
+{
+	struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
+	struct list_head *tmp, *tmp1, *tmp2;
+	struct TCP_Server_Info *server;
+	struct cifs_ses *ses;
+	struct cifs_tcon *tcon;
+	struct smb2_lease_break_work *lw;
 
-				spin_unlock(&cifs_file_list_lock);
-				spin_unlock(&cifs_tcp_ses_lock);
-				return true;
-			}
+	lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
+	if (!lw)
+		return false;
 
-			found = false;
-			list_for_each_entry(open, &tcon->pending_opens, olist) {
-				if (memcmp(open->lease_key, rsp->LeaseKey,
-					   SMB2_LEASE_KEY_SIZE))
-					continue;
+	INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
+	lw->lease_state = rsp->NewLeaseState;
 
-				if (!found && ack_req) {
-					found = true;
-					memcpy(lw->lease_key, open->lease_key,
-					       SMB2_LEASE_KEY_SIZE);
-					lw->tlink = cifs_get_tlink(open->tlink);
-					queue_work(cifsiod_wq,
-						   &lw->lease_break);
-				}
+	cifs_dbg(FYI, "Checking for lease break\n");
+
+	/* look up tcon based on tid & uid */
+	spin_lock(&cifs_tcp_ses_lock);
+	list_for_each(tmp, &cifs_tcp_ses_list) {
+		server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
 
-				cifs_dbg(FYI, "found in the pending open list\n");
-				cifs_dbg(FYI, "lease key match, lease break 0x%d\n",
-					 le32_to_cpu(rsp->NewLeaseState));
+		list_for_each(tmp1, &server->smb_ses_list) {
+			ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
 
-				open->oplock =
-				  smb2_map_lease_to_oplock(rsp->NewLeaseState);
-			}
-			if (found) {
-				spin_unlock(&cifs_file_list_lock);
-				spin_unlock(&cifs_tcp_ses_lock);
-				return true;
+			spin_lock(&cifs_file_list_lock);
+			list_for_each(tmp2, &ses->tcon_list) {
+				tcon = list_entry(tmp2, struct cifs_tcon,
+						  tcon_list);
+				cifs_stats_inc(
+				    &tcon->stats.cifs_stats.num_oplock_brks);
+				if (smb2_tcon_has_lease(tcon, rsp, lw)) {
+					spin_unlock(&cifs_file_list_lock);
+					spin_unlock(&cifs_tcp_ses_lock);
+					return true;
+				}
 			}
+			spin_unlock(&cifs_file_list_lock);
 		}
-		spin_unlock(&cifs_file_list_lock);
 	}
 	spin_unlock(&cifs_tcp_ses_lock);
 	kfree(lw);
@@ -528,7 +540,7 @@ smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 	if (rsp->StructureSize !=
 				smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
 		if (le16_to_cpu(rsp->StructureSize) == 44)
-			return smb2_is_valid_lease_break(buffer, server);
+			return smb2_is_valid_lease_break(buffer);
 		else
 			return false;
 	}
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index ccbfbbb12dc..904ca1a21dc 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4706,7 +4706,9 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 		ext4_journal_stop(handle);
 	}
 
-	if (attr->ia_valid & ATTR_SIZE) {
+	if (attr->ia_valid & ATTR_SIZE && attr->ia_size != inode->i_size) {
+		handle_t *handle;
+		loff_t oldsize = inode->i_size;
 
 		if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
 			struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
@@ -4714,73 +4716,60 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 			if (attr->ia_size > sbi->s_bitmap_maxbytes)
 				return -EFBIG;
 		}
-	}
-
-	if (S_ISREG(inode->i_mode) &&
-	    attr->ia_valid & ATTR_SIZE &&
-	    (attr->ia_size < inode->i_size)) {
-		handle_t *handle;
-
-		handle = ext4_journal_start(inode, EXT4_HT_INODE, 3);
-		if (IS_ERR(handle)) {
-			error = PTR_ERR(handle);
-			goto err_out;
-		}
-		if (ext4_handle_valid(handle)) {
-			error = ext4_orphan_add(handle, inode);
-			orphan = 1;
-		}
-		EXT4_I(inode)->i_disksize = attr->ia_size;
-		rc = ext4_mark_inode_dirty(handle, inode);
-		if (!error)
-			error = rc;
-		ext4_journal_stop(handle);
-
-		if (ext4_should_order_data(inode)) {
-			error = ext4_begin_ordered_truncate(inode,
+		if (S_ISREG(inode->i_mode) &&
+		    (attr->ia_size < inode->i_size)) {
+			if (ext4_should_order_data(inode)) {
+				error = ext4_begin_ordered_truncate(inode,
 							    attr->ia_size);
-			if (error) {
-				/* Do as much error cleanup as possible */
-				handle = ext4_journal_start(inode,
-							    EXT4_HT_INODE, 3);
-				if (IS_ERR(handle)) {
-					ext4_orphan_del(NULL, inode);
+				if (error)
 					goto err_out;
-				}
-				ext4_orphan_del(handle, inode);
-				orphan = 0;
-				ext4_journal_stop(handle);
+			}
+			handle = ext4_journal_start(inode, EXT4_HT_INODE, 3);
+			if (IS_ERR(handle)) {
+				error = PTR_ERR(handle);
+				goto err_out;
+			}
+			if (ext4_handle_valid(handle)) {
+				error = ext4_orphan_add(handle, inode);
+				orphan = 1;
+			}
+			EXT4_I(inode)->i_disksize = attr->ia_size;
+			rc = ext4_mark_inode_dirty(handle, inode);
+			if (!error)
+				error = rc;
+			ext4_journal_stop(handle);
+			if (error) {
+				ext4_orphan_del(NULL, inode);
 				goto err_out;
 			}
 		}
-	}
-
-	if (attr->ia_valid & ATTR_SIZE) {
-		if (attr->ia_size != inode->i_size) {
-			loff_t oldsize = inode->i_size;
 
-			i_size_write(inode, attr->ia_size);
-			/*
-			 * Blocks are going to be removed from the inode. Wait
-			 * for dio in flight.  Temporarily disable
-			 * dioread_nolock to prevent livelock.
-			 */
-			if (orphan) {
-				if (!ext4_should_journal_data(inode)) {
-					ext4_inode_block_unlocked_dio(inode);
-					inode_dio_wait(inode);
-					ext4_inode_resume_unlocked_dio(inode);
-				} else
-					ext4_wait_for_tail_page_commit(inode);
-			}
-			/*
-			 * Truncate pagecache after we've waited for commit
-			 * in data=journal mode to make pages freeable.
-			 */
-			truncate_pagecache(inode, oldsize, inode->i_size);
+		i_size_write(inode, attr->ia_size);
+		/*
+		 * Blocks are going to be removed from the inode. Wait
+		 * for dio in flight.  Temporarily disable
+		 * dioread_nolock to prevent livelock.
+		 */
+		if (orphan) {
+			if (!ext4_should_journal_data(inode)) {
+				ext4_inode_block_unlocked_dio(inode);
+				inode_dio_wait(inode);
+				ext4_inode_resume_unlocked_dio(inode);
+			} else
+				ext4_wait_for_tail_page_commit(inode);
 		}
-		ext4_truncate(inode);
+		/*
+		 * Truncate pagecache after we've waited for commit
+		 * in data=journal mode to make pages freeable.
+		 */
+		truncate_pagecache(inode, oldsize, inode->i_size);
 	}
+	/*
+	 * We want to call ext4_truncate() even if attr->ia_size ==
+	 * inode->i_size for cases like truncation of fallocated space
+	 */
+	if (attr->ia_valid & ATTR_SIZE)
+		ext4_truncate(inode);
 
 	if (!rc) {
 		setattr_copy(inode, attr);
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 5b1274699b0..e67b13de2eb 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -1175,6 +1175,8 @@ static int parse_dirfile(char *buf, size_t nbytes, struct file *file,
 			return -EIO;
 		if (reclen > nbytes)
 			break;
+		if (memchr(dirent->name, '/', dirent->namelen) != NULL)
+			return -EIO;
 
 		over = filldir(dstbuf, dirent->name, dirent->namelen,
 			       file->f_pos, dirent->ino, dirent->type);
@@ -1323,6 +1325,8 @@ static int parse_dirplusfile(char *buf, size_t nbytes, struct file *file,
 			return -EIO;
 		if (reclen > nbytes)
 			break;
+		if (memchr(dirent->name, '/', dirent->namelen) != NULL)
+			return -EIO;
 
 		if (!over) {
 			/* We fill entries into dstbuf only as much as
@@ -1594,6 +1598,7 @@ int fuse_do_setattr(struct inode *inode, struct iattr *attr,
 		    struct file *file)
 {
 	struct fuse_conn *fc = get_fuse_conn(inode);
+	struct fuse_inode *fi = get_fuse_inode(inode);
 	struct fuse_req *req;
 	struct fuse_setattr_in inarg;
 	struct fuse_attr_out outarg;
@@ -1621,8 +1626,10 @@ int fuse_do_setattr(struct inode *inode, struct iattr *attr,
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
-	if (is_truncate)
+	if (is_truncate) {
 		fuse_set_nowrite(inode);
+		set_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
+	}
 
 	memset(&inarg, 0, sizeof(inarg));
 	memset(&outarg, 0, sizeof(outarg));
@@ -1684,12 +1691,14 @@ int fuse_do_setattr(struct inode *inode, struct iattr *attr,
 		invalidate_inode_pages2(inode->i_mapping);
 	}
 
+	clear_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
 	return 0;
 
 error:
 	if (is_truncate)
 		fuse_release_nowrite(inode);
 
+	clear_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
 	return err;
 }
 
@@ -1753,6 +1762,8 @@ static int fuse_setxattr(struct dentry *entry, const char *name,
 		fc->no_setxattr = 1;
 		err = -EOPNOTSUPP;
 	}
+	if (!err)
+		fuse_invalidate_attr(inode);
 	return err;
 }
 
@@ -1882,6 +1893,8 @@ static int fuse_removexattr(struct dentry *entry, const char *name)
 		fc->no_removexattr = 1;
 		err = -EOPNOTSUPP;
 	}
+	if (!err)
+		fuse_invalidate_attr(inode);
 	return err;
 }
 
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 35f28103314..473e8453a7d 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -630,7 +630,8 @@ static void fuse_read_update_size(struct inode *inode, loff_t size,
 	struct fuse_inode *fi = get_fuse_inode(inode);
 
 	spin_lock(&fc->lock);
-	if (attr_ver == fi->attr_version && size < inode->i_size) {
+	if (attr_ver == fi->attr_version && size < inode->i_size &&
+	    !test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) {
 		fi->attr_version = ++fc->attr_version;
 		i_size_write(inode, size);
 	}
@@ -1033,12 +1034,16 @@ static ssize_t fuse_perform_write(struct file *file,
 {
 	struct inode *inode = mapping->host;
 	struct fuse_conn *fc = get_fuse_conn(inode);
+	struct fuse_inode *fi = get_fuse_inode(inode);
 	int err = 0;
 	ssize_t res = 0;
 
 	if (is_bad_inode(inode))
 		return -EIO;
 
+	if (inode->i_size < pos + iov_iter_count(ii))
+		set_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
+
 	do {
 		struct fuse_req *req;
 		ssize_t count;
@@ -1074,6 +1079,7 @@ static ssize_t fuse_perform_write(struct file *file,
 	if (res > 0)
 		fuse_write_update_size(inode, pos);
 
+	clear_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
 	fuse_invalidate_attr(inode);
 
 	return res > 0 ? res : err;
@@ -1530,7 +1536,6 @@ static int fuse_writepage_locked(struct page *page)
 
 	inc_bdi_stat(mapping->backing_dev_info, BDI_WRITEBACK);
 	inc_zone_page_state(tmp_page, NR_WRITEBACK_TEMP);
-	end_page_writeback(page);
 
 	spin_lock(&fc->lock);
 	list_add(&req->writepages_entry, &fi->writepages);
@@ -1538,6 +1543,8 @@ static int fuse_writepage_locked(struct page *page)
 	fuse_flush_writepages(inode);
 	spin_unlock(&fc->lock);
 
+	end_page_writeback(page);
+
 	return 0;
 
 err_free:
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index fde7249a3a9..5ced199b50b 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -115,6 +115,8 @@ struct fuse_inode {
 enum {
 	/** Advise readdirplus  */
 	FUSE_I_ADVISE_RDPLUS,
+	/** An operation changing file size is in progress  */
+	FUSE_I_SIZE_UNSTABLE,
 };
 
 struct fuse_conn;
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 9a0cdde14a0..b5718516825 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -201,7 +201,8 @@ void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
 	struct timespec old_mtime;
 
 	spin_lock(&fc->lock);
-	if (attr_version != 0 && fi->attr_version > attr_version) {
+	if ((attr_version != 0 && fi->attr_version > attr_version) ||
+	    test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) {
 		spin_unlock(&fc->lock);
 		return;
 	}
diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index d9b8aebdeb2..d3705490ff9 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -125,8 +125,8 @@ static void destroy_inodecache(void)
 
 static int isofs_remount(struct super_block *sb, int *flags, char *data)
 {
-	/* we probably want a lot more here */
-	*flags |= MS_RDONLY;
+	if (!(*flags & MS_RDONLY))
+		return -EROFS;
 	return 0;
 }
 
@@ -779,15 +779,6 @@ root_found:
 	 */
 	s->s_maxbytes = 0x80000000000LL;
 
-	/*
-	 * The CDROM is read-only, has no nodes (devices) on it, and since
-	 * all of the files appear to be owned by root, we really do not want
-	 * to allow suid.  (suid or devices will not show up unless we have
-	 * Rock Ridge extensions)
-	 */
-
-	s->s_flags |= MS_RDONLY /* | MS_NODEV | MS_NOSUID */;
-
 	/* Set this for reference. Its not currently used except on write
 	   which we don't have .. */
 
@@ -1546,6 +1537,9 @@ struct inode *isofs_iget(struct super_block *sb,
 static struct dentry *isofs_mount(struct file_system_type *fs_type,
 	int flags, const char *dev_name, void *data)
 {
+	/* We don't support read-write mounts */
+	if (!(flags & MS_RDONLY))
+		return ERR_PTR(-EACCES);
 	return mount_bdev(fs_type, flags, dev_name, data, isofs_fill_super);
 }
 
diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c
index 2487116d0d3..84606472668 100644
--- a/fs/ocfs2/extent_map.c
+++ b/fs/ocfs2/extent_map.c
@@ -781,7 +781,6 @@ int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 	cpos = map_start >> osb->s_clustersize_bits;
 	mapping_end = ocfs2_clusters_for_bytes(inode->i_sb,
 					       map_start + map_len);
-	mapping_end -= cpos;
 	is_last = 0;
 	while (cpos < mapping_end && !is_last) {
 		u32 fe_flags;
diff --git a/fs/proc/root.c b/fs/proc/root.c
index 41a6ea93f48..04ec276c7ba 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -110,7 +110,8 @@ static struct dentry *proc_mount(struct file_system_type *fs_type,
 		ns = task_active_pid_ns(current);
 		options = data;
 
-		if (!current_user_ns()->may_mount_proc)
+		if (!current_user_ns()->may_mount_proc ||
+		    !ns_capable(ns->user_ns, CAP_SYS_ADMIN))
 			return ERR_PTR(-EPERM);
 	}