From 488968a8945c119859d91bb6a8dc13bf50002f15 Mon Sep 17 00:00:00 2001 From: Ronnie Sahlberg Date: Fri, 23 Jul 2021 11:21:24 +1000 Subject: [PATCH] cifs: fix fallocate when trying to allocate a hole. Remove the conditional checking for out_data_len and skipping the fallocate if it is 0. This is wrong will actually change any legitimate the fallocate where the entire region is unallocated into a no-op. Additionally, before allocating the range, if FALLOC_FL_KEEP_SIZE is set then we need to clamp the length of the fallocate region as to not extend the size of the file. Fixes: 966a3cb7c7db ("cifs: improve fallocate emulation") Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French --- fs/cifs/smb2ops.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 5cefb59..23d6f4d 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -3667,11 +3667,6 @@ static int smb3_simple_fallocate_range(unsigned int xid, (char **)&out_data, &out_data_len); if (rc) goto out; - /* - * It is already all allocated - */ - if (out_data_len == 0) - goto out; buf = kzalloc(1024 * 1024, GFP_KERNEL); if (buf == NULL) { @@ -3794,6 +3789,24 @@ static long smb3_simple_falloc(struct file *file, struct cifs_tcon *tcon, goto out; } + if (keep_size == true) { + /* + * We can not preallocate pages beyond the end of the file + * in SMB2 + */ + if (off >= i_size_read(inode)) { + rc = 0; + goto out; + } + /* + * For fallocates that are partially beyond the end of file, + * clamp len so we only fallocate up to the end of file. + */ + if (off + len > i_size_read(inode)) { + len = i_size_read(inode) - off; + } + } + if ((keep_size == true) || (i_size_read(inode) >= off + len)) { /* * At this point, we are trying to fallocate an internal -- 2.7.4