Patch "libfs: Define a minimum directory offset" has been added to the 6.8-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    libfs: Define a minimum directory offset

to the 6.8-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     libfs-define-a-minimum-directory-offset.patch
and it can be found in the queue-6.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 8efb0e5921d1e230ea84fad54a733132a1425b5d
Author: Chuck Lever <chuck.lever@xxxxxxxxxx>
Date:   Sat Feb 17 15:23:47 2024 -0500

    libfs: Define a minimum directory offset
    
    [ Upstream commit 7beea725a8ca412c6190090ce7c3a13b169592a1 ]
    
    This value is used in several places, so make it a symbolic
    constant.
    
    Reviewed-by: Jan Kara <jack@xxxxxxx>
    Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/170820142741.6328.12428356024575347885.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
    Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
    Stable-dep-of: 23cdd0eed3f1 ("libfs: Fix simple_offset_rename_exchange()")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/fs/libfs.c b/fs/libfs.c
index 752e24c669d97..f0045db739df8 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -240,6 +240,11 @@ const struct inode_operations simple_dir_inode_operations = {
 };
 EXPORT_SYMBOL(simple_dir_inode_operations);
 
+/* 0 is '.', 1 is '..', so always start with offset 2 or more */
+enum {
+	DIR_OFFSET_MIN	= 2,
+};
+
 static void offset_set(struct dentry *dentry, u32 offset)
 {
 	dentry->d_fsdata = (void *)((uintptr_t)(offset));
@@ -261,9 +266,7 @@ void simple_offset_init(struct offset_ctx *octx)
 {
 	xa_init_flags(&octx->xa, XA_FLAGS_ALLOC1);
 	lockdep_set_class(&octx->xa.xa_lock, &simple_offset_xa_lock);
-
-	/* 0 is '.', 1 is '..', so always start with offset 2 */
-	octx->next_offset = 2;
+	octx->next_offset = DIR_OFFSET_MIN;
 }
 
 /**
@@ -276,7 +279,7 @@ void simple_offset_init(struct offset_ctx *octx)
  */
 int simple_offset_add(struct offset_ctx *octx, struct dentry *dentry)
 {
-	static const struct xa_limit limit = XA_LIMIT(2, U32_MAX);
+	static const struct xa_limit limit = XA_LIMIT(DIR_OFFSET_MIN, U32_MAX);
 	u32 offset;
 	int ret;
 
@@ -481,7 +484,7 @@ static int offset_readdir(struct file *file, struct dir_context *ctx)
 		return 0;
 
 	/* In this case, ->private_data is protected by f_pos_lock */
-	if (ctx->pos == 2)
+	if (ctx->pos == DIR_OFFSET_MIN)
 		file->private_data = NULL;
 	else if (file->private_data == ERR_PTR(-ENOENT))
 		return 0;