This series fixes following bugs:

When lseek() a file secondly opened with O_ACCMODE|O_DIRECT flags,
nfs4_valid_open_stateid() will dereference NULL nfs4_state.

open() with O_ACCMODE|O_DIRECT flags secondly will fail.

ChenXiaoSong (2):
  Revert "NFSv4: Handle the special Linux file open access mode"
  NFSv4: fix open failure with O_ACCMODE flag

 fs/nfs/dir.c      | 10 ----------
 fs/nfs/inode.c    |  1 -
 fs/nfs/internal.h | 10 ++++++++++
 fs/nfs/nfs4file.c |  6 ++++--
 4 files changed, 14 insertions(+), 13 deletions(-)

-- 
2.31.1

在 2022/3/29 19:32, ChenXiaoSong 写道:
> This series fixes following bugs:
> 
> When lseek() a file secondly opened with O_ACCMODE|O_DIRECT flags,
> nfs4_valid_open_stateid() will dereference NULL nfs4_state.
> 
> open() with O_ACCMODE|O_DIRECT flags secondly will fail.
> 
> ChenXiaoSong (2):
>    Revert "NFSv4: Handle the special Linux file open access mode"
>    NFSv4: fix open failure with O_ACCMODE flag
> 
>   fs/nfs/dir.c      | 10 ----------
>   fs/nfs/inode.c    |  1 -
>   fs/nfs/internal.h | 10 ++++++++++
>   fs/nfs/nfs4file.c |  6 ++++--
>   4 files changed, 14 insertions(+), 13 deletions(-)
> 

I wonder if these bugs related to 
[CVE-2022-24448](https://nvd.nist.gov/vuln/detail/CVE-2022-24448) ?

[Question about 
CVE-2022-24448](https://lore.kernel.org/all/1bb42908-8f58-bf56-c2da-42739ee48d16@huawei.com/T/)

Is there POC of patch ac795161c936 ("NFSv4: Handle case where the lookup 
of a directory fails") ?

CVE-2022-24448 Description:
An issue was discovered in fs/nfs/dir.c in the Linux kernel before 
5.16.5. If an application sets the O_DIRECTORY flag, and tries to open a 
regular file, nfs_atomic_open() performs a regular lookup. If a regular 
file is found, ENOTDIR should occur, but the server instead returns 
uninitialized data in the file descriptor.