Re: [PATCH] 9pfs: local: Do not follow symlink in _nofollow

[Christian Schoenebeck <qemu_oss@crudebyte.com>]

On Mittwoch, 27. April 2022 04:45:45 CEST Akihiko Odaki wrote:
> Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
> ---
>  hw/9pfs/9p-local.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c
> index d42ce6d8b82..def8afdb4d6 100644
> --- a/hw/9pfs/9p-local.c
> +++ b/hw/9pfs/9p-local.c
> @@ -365,7 +365,7 @@ static int fchmodat_nofollow(int dirfd, const char
> *name, mode_t mode) if (fd == -1) {
>          /* In case the file is writable-only and isn't a directory. */
>          if (errno == EACCES) {
> -            fd = openat_file(dirfd, name, O_WRONLY, 0);
> +            fd = openat_file(dirfd, name, O_WRONLY | O_NOFOLLOW, 0);

O_NOFOLLOW flag is always added inside openat_file() implementation:

https://github.com/qemu/qemu/blob/master/hw/9pfs/9p-util.h#L60

So this change is not necessary AFAICS.

>          }
>          if (fd == -1 && errno == EISDIR) {
>              errno = EACCES;