From cbe1e057713869254ba7f18daf63e6341230e984 Mon Sep 17 00:00:00 2001
From: Brian Gianforcaro <bgianf@serenityos.org>
Date: Fri, 28 May 2021 05:41:31 -0700
Subject: [PATCH] Kernel: Move ProcFS API towards OOM safety

---
 Kernel/FileSystem/ProcFS.cpp | 10 ++++++----
 Kernel/FileSystem/ProcFS.h   |  2 +-
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/Kernel/FileSystem/ProcFS.cpp b/Kernel/FileSystem/ProcFS.cpp
index fc458844aa..434ba03257 100644
--- a/Kernel/FileSystem/ProcFS.cpp
+++ b/Kernel/FileSystem/ProcFS.cpp
@@ -234,9 +234,9 @@ struct ProcFSInodeData : public FileDescriptionData {
     RefPtr<KBufferImpl> buffer;
 };
 
-NonnullRefPtr<ProcFS> ProcFS::create()
+RefPtr<ProcFS> ProcFS::create()
 {
-    return adopt_ref(*new ProcFS);
+    return adopt_ref_if_nonnull(new ProcFS);
 }
 
 ProcFS::~ProcFS()
@@ -1015,10 +1015,12 @@ RefPtr<Inode> ProcFS::get_inode(InodeIdentifier inode_id) const
         // and if that fails we cannot return this instance anymore and just
         // create a new one.
         if (it->value->try_ref())
-            return adopt_ref(*it->value);
+            return adopt_ref_if_nonnull(it->value);
         // We couldn't ref it, so just create a new one and replace the entry
     }
-    auto inode = adopt_ref(*new ProcFSInode(const_cast<ProcFS&>(*this), inode_id.index()));
+    auto inode = adopt_ref_if_nonnull(new ProcFSInode(const_cast<ProcFS&>(*this), inode_id.index()));
+    if (!inode)
+        return {};
     auto result = m_inodes.set(inode_id.index().value(), inode.ptr());
     VERIFY(result == ((it == m_inodes.end()) ? AK::HashSetResult::InsertedNewEntry : AK::HashSetResult::ReplacedExistingEntry));
     return inode;
diff --git a/Kernel/FileSystem/ProcFS.h b/Kernel/FileSystem/ProcFS.h
index b54acbd0f7..4c34709811 100644
--- a/Kernel/FileSystem/ProcFS.h
+++ b/Kernel/FileSystem/ProcFS.h
@@ -24,7 +24,7 @@ class ProcFS final : public FS {
 
 public:
     virtual ~ProcFS() override;
-    static NonnullRefPtr<ProcFS> create();
+    static RefPtr<ProcFS> create();
 
     virtual bool initialize() override;
     virtual const char* class_name() const override;