| From fbd932a6124b49cb6d8fc4554f883d3b0af04760 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Fri, 23 Jul 2021 11:21:24 +1000 |
| Subject: cifs: fix fallocate when trying to allocate a hole. |
| |
| From: Ronnie Sahlberg <lsahlber@redhat.com> |
| |
| [ Upstream commit 488968a8945c119859d91bb6a8dc13bf50002f15 ] |
| |
| 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 <lsahlber@redhat.com> |
| Signed-off-by: Steve French <stfrench@microsoft.com> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| 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 cc253bbff696..64cad843ce72 100644 |
| --- a/fs/cifs/smb2ops.c |
| +++ b/fs/cifs/smb2ops.c |
| @@ -3663,11 +3663,6 @@ 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) { |
| @@ -3790,6 +3785,24 @@ 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 |
| -- |
| 2.30.2 |
| |