From 9708b080608f70250ed72121927004a42f549c4a Mon Sep 17 00:00:00 2001
From: Augustin Cavalier <waddlesplash@gmail.com>
Date: Fri, 22 Nov 2024 16:56:15 -0500
Subject: [PATCH] KPath: Use a default buffer size of B_PATH_NAME_LENGTH
 without + 1.

B_PATH_NAME_LENGTH == PATH_MAX, and PATH_MAX is inclusive of the final
NULL terminator, so we don't need a + 1 here.

The original KPath default was to not use + 1, but that was changed in
42e3c6f97874f37701385e7027c77e4366d7c450 due to all the consumers that did.

But all those consumers are wrong, it appears; they should just be
using the default length instead. So now we do that.
---
 headers/private/kernel/fs/KPath.h |  7 ++++---
 src/system/kernel/fs/KPath.cpp    | 10 ++++++----
 src/system/kernel/fs/vfs.cpp      |  2 +-
 3 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/headers/private/kernel/fs/KPath.h b/headers/private/kernel/fs/KPath.h
index 372b02fc2d..726ed810f8 100644
--- a/headers/private/kernel/fs/KPath.h
+++ b/headers/private/kernel/fs/KPath.h
@@ -22,15 +22,16 @@ public:
 		TRAVERSE_LEAF_LINK = 0x02,
 		LAZY_ALLOC = 0x04
 	};
+
 public:
-								KPath(size_t bufferSize = B_PATH_NAME_LENGTH + 1);
+								KPath(size_t bufferSize = B_PATH_NAME_LENGTH);
 								KPath(const char* path, int32 flags = DEFAULT,
-									size_t bufferSize = B_PATH_NAME_LENGTH + 1);
+									size_t bufferSize = B_PATH_NAME_LENGTH);
 								KPath(const KPath& other);
 								~KPath();
 
 			status_t			SetTo(const char* path, int32 flags = DEFAULT,
-									size_t bufferSize = B_PATH_NAME_LENGTH + 1);
+									size_t bufferSize = B_PATH_NAME_LENGTH);
 			void				Adopt(KPath& other);
 
 			status_t			InitCheck() const;
diff --git a/src/system/kernel/fs/KPath.cpp b/src/system/kernel/fs/KPath.cpp
index cfca5be237..32ded8b69d 100644
--- a/src/system/kernel/fs/KPath.cpp
+++ b/src/system/kernel/fs/KPath.cpp
@@ -80,7 +80,7 @@ status_t
 KPath::SetTo(const char* path, int32 flags, size_t bufferSize)
 {
 	if (bufferSize == 0)
-		bufferSize = B_PATH_NAME_LENGTH + 1;
+		bufferSize = B_PATH_NAME_LENGTH;
 
 	// free the previous buffer, if the buffer size differs
 	if (fBuffer != NULL && fBufferSize != bufferSize) {
@@ -249,11 +249,13 @@ KPath::DetachBuffer()
 {
 	char* buffer = fBuffer;
 
-	if (fBufferSize == (B_PATH_NAME_LENGTH + 1)) {
+#ifdef _KERNEL_MODE
+	if (fBufferSize == B_PATH_NAME_LENGTH) {
 		buffer = (char*)malloc(fBufferSize);
 		memcpy(buffer, fBuffer, fBufferSize);
 		_FreeBuffer();
 	}
+#endif
 
 	if (fBuffer != NULL) {
 		fBuffer = NULL;
@@ -427,7 +429,7 @@ KPath::_AllocateBuffer()
 {
 	if (fBuffer == NULL && fBufferSize != 0) {
 #ifdef _KERNEL_MODE
-		if (fBufferSize == (B_PATH_NAME_LENGTH + 1))
+		if (fBufferSize == B_PATH_NAME_LENGTH)
 			fBuffer = (char*)object_cache_alloc(sPathNameCache, 0);
 		else
 #endif
@@ -448,7 +450,7 @@ void
 KPath::_FreeBuffer()
 {
 #ifdef _KERNEL_MODE
-	if (fBufferSize == (B_PATH_NAME_LENGTH + 1))
+	if (fBufferSize == B_PATH_NAME_LENGTH)
 		object_cache_free(sPathNameCache, fBuffer, 0);
 	else
 #endif
diff --git a/src/system/kernel/fs/vfs.cpp b/src/system/kernel/fs/vfs.cpp
index 85e2098512..2a5dbbbccb 100644
--- a/src/system/kernel/fs/vfs.cpp
+++ b/src/system/kernel/fs/vfs.cpp
@@ -5284,7 +5284,7 @@ vfs_init(kernel_args* args)
 		panic("vfs_init: error creating mounts hash table\n");
 
 	sPathNameCache = create_object_cache("vfs path names",
-		B_PATH_NAME_LENGTH + 1, 8, NULL, NULL, NULL);
+		B_PATH_NAME_LENGTH, 8, NULL, NULL, NULL);
 	if (sPathNameCache == NULL)
 		panic("vfs_init: error creating path name object_cache\n");