On Tue, Jul 01, 2025 at 11:50:43PM -0400, Theodore Ts'o wrote:
> Commit 9f69dfc4e275 ("fuse2fs: implement O_APPEND correctly") defined
> a new flag, A_OK, to add support for testing whether the file is valid
> for append operations. This is relevant for the check_iflags_access()
> function, but when are later testing operations mask against the inode
> permissions, this new flag gets in the way and causes non-root users
> attempting to create new inodes in a directory to fail. Fix this by
> masking off A_OK before doing these tests.
>
> Fixes: 9f69dfc4e275 ("fuse2fs: implement O_APPEND correctly")
> Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Looks correct to me,
Reviewed-by: "Darrick J. Wong" <djwong@xxxxxxxxxx>
--D
> ---
> misc/fuse2fs.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/misc/fuse2fs.c b/misc/fuse2fs.c
> index bb75d9421..d209bc790 100644
> --- a/misc/fuse2fs.c
> +++ b/misc/fuse2fs.c
> @@ -687,6 +687,9 @@ static int check_inum_access(struct fuse2fs *ff, ext2_ino_t ino, int mask)
> return -EACCES;
> }
>
> + /* Remove the O_APPEND flag before testing permissions */
> + mask &= ~A_OK;
> +
> /* allow owner, if perms match */
> if (inode_uid(inode) == ctxt->uid) {
> if ((mask & (perms >> 6)) == mask)
> --
> 2.47.2
>
>
