Patch "btrfs: use u64 for buffer sizes in the tree search ioctls" has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

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

    btrfs: use u64 for buffer sizes in the tree search ioctls

to the 5.15-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:
     btrfs-use-u64-for-buffer-sizes-in-the-tree-search-io.patch
and it can be found in the queue-5.15 subdirectory.

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



commit fb0c323f01ffa42ffed77825e0acdd557cf02fd8
Author: Filipe Manana <fdmanana@xxxxxxxx>
Date:   Fri Oct 13 10:05:48 2023 +0100

    btrfs: use u64 for buffer sizes in the tree search ioctls
    
    [ Upstream commit dec96fc2dcb59723e041416b8dc53e011b4bfc2e ]
    
    In the tree search v2 ioctl we use the type size_t, which is an unsigned
    long, to track the buffer size in the local variable 'buf_size'. An
    unsigned long is 32 bits wide on a 32 bits architecture. The buffer size
    defined in struct btrfs_ioctl_search_args_v2 is a u64, so when we later
    try to copy the local variable 'buf_size' to the argument struct, when
    the search returns -EOVERFLOW, we copy only 32 bits which will be a
    problem on big endian systems.
    
    Fix this by using a u64 type for the buffer sizes, not only at
    btrfs_ioctl_tree_search_v2(), but also everywhere down the call chain
    so that we can use the u64 at btrfs_ioctl_tree_search_v2().
    
    Fixes: cc68a8a5a433 ("btrfs: new ioctl TREE_SEARCH_V2")
    Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
    Link: https://lore.kernel.org/linux-btrfs/ce6f4bd6-9453-4ffe-ba00-cee35495e10f@moroto.mountain/
    Signed-off-by: Filipe Manana <fdmanana@xxxxxxxx>
    Reviewed-by: David Sterba <dsterba@xxxxxxxx>
    Signed-off-by: David Sterba <dsterba@xxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index dc9f4f80f90b6..f93d15833f9de 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2094,7 +2094,7 @@ static noinline int key_in_sk(struct btrfs_key *key,
 static noinline int copy_to_sk(struct btrfs_path *path,
 			       struct btrfs_key *key,
 			       struct btrfs_ioctl_search_key *sk,
-			       size_t *buf_size,
+			       u64 *buf_size,
 			       char __user *ubuf,
 			       unsigned long *sk_offset,
 			       int *num_found)
@@ -2226,7 +2226,7 @@ static noinline int copy_to_sk(struct btrfs_path *path,
 
 static noinline int search_ioctl(struct inode *inode,
 				 struct btrfs_ioctl_search_key *sk,
-				 size_t *buf_size,
+				 u64 *buf_size,
 				 char __user *ubuf)
 {
 	struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
@@ -2295,7 +2295,7 @@ static noinline int btrfs_ioctl_tree_search(struct file *file,
 	struct btrfs_ioctl_search_key sk;
 	struct inode *inode;
 	int ret;
-	size_t buf_size;
+	u64 buf_size;
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
@@ -2329,8 +2329,8 @@ static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
 	struct btrfs_ioctl_search_args_v2 args;
 	struct inode *inode;
 	int ret;
-	size_t buf_size;
-	const size_t buf_limit = SZ_16M;
+	u64 buf_size;
+	const u64 buf_limit = SZ_16M;
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;