From 7e3ae33efad1490d01040f552ef50e58ed6376ca Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Fri, 23 May 2014 20:15:16 +0100 Subject: [PATCH] Btrfs: send, use the right limits for xattr names and values We were limiting the sum of the xattr name and value lengths to PATH_MAX, which is not correct, specially on filesystems created with btrfs-progs v3.12 or higher, where the default leaf size is max(16384, PAGE_SIZE), or systems with page sizes larger than 4096 bytes. Xattrs have their own specific maximum name and value lengths, which depend on the leaf size, therefore use these limits to be able to send xattrs with sizes larger than PATH_MAX. A test case for xfstests follows. Signed-off-by: Filipe David Borba Manana Signed-off-by: Chris Mason --- fs/btrfs/send.c | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index 15cdc67ce9ad..6528aa662181 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -975,7 +975,7 @@ static int iterate_dir_item(struct btrfs_root *root, struct btrfs_path *path, struct btrfs_dir_item *di; struct btrfs_key di_key; char *buf = NULL; - const int buf_len = PATH_MAX; + int buf_len; u32 name_len; u32 data_len; u32 cur; @@ -985,6 +985,11 @@ static int iterate_dir_item(struct btrfs_root *root, struct btrfs_path *path, int num; u8 type; + if (found_key->type == BTRFS_XATTR_ITEM_KEY) + buf_len = BTRFS_MAX_XATTR_SIZE(root); + else + buf_len = PATH_MAX; + buf = kmalloc(buf_len, GFP_NOFS); if (!buf) { ret = -ENOMEM; @@ -1006,12 +1011,23 @@ static int iterate_dir_item(struct btrfs_root *root, struct btrfs_path *path, type = btrfs_dir_type(eb, di); btrfs_dir_item_key_to_cpu(eb, di, &di_key); - /* - * Path too long - */ - if (name_len + data_len > buf_len) { - ret = -ENAMETOOLONG; - goto out; + if (type == BTRFS_FT_XATTR) { + if (name_len > XATTR_NAME_MAX) { + ret = -ENAMETOOLONG; + goto out; + } + if (name_len + data_len > buf_len) { + ret = -E2BIG; + goto out; + } + } else { + /* + * Path too long + */ + if (name_len + data_len > buf_len) { + ret = -ENAMETOOLONG; + goto out; + } } read_extent_buffer(eb, buf, (unsigned long)(di + 1), -- 2.34.1