On Thu, Jan 14, 2021 at 10:02 AM Petr Lautrbach <plautrba@xxxxxxxxxx> wrote:
>
> According to mmap(2) after the mmap() call has returned, the file
> descriptor, fd, can be closed immediately without invalidating the
> mapping.
>
> Signed-off-by: Petr Lautrbach <plautrba@xxxxxxxxxx>
> ---
>
> Changes against v1:
> - selinux_status_fd is completely droped as it's actually unused
>
> libselinux/src/sestatus.c | 7 +------
> 1 file changed, 1 insertion(+), 6 deletions(-)
>
> diff --git a/libselinux/src/sestatus.c b/libselinux/src/sestatus.c
> index 9ff2785d876a..12b015e088ea 100644
> --- a/libselinux/src/sestatus.c
> +++ b/libselinux/src/sestatus.c
> @@ -37,7 +37,6 @@ struct selinux_status_t
> * Valid Pointer : opened and mapped correctly
> */
> static struct selinux_status_t *selinux_status = NULL;
> -static int selinux_status_fd;
> static uint32_t last_seqno;
> static uint32_t last_policyload;
>
> @@ -298,11 +297,10 @@ int selinux_status_open(int fallback)
> goto error;
>
> selinux_status = mmap(NULL, pagesize, PROT_READ, MAP_SHARED, fd, 0);
> + close(fd);
> if (selinux_status == MAP_FAILED) {
> - close(fd);
> goto error;
> }
> - selinux_status_fd = fd;
> last_seqno = (uint32_t)(-1);
>
> /* sequence must not be changed during references */
> @@ -336,7 +334,6 @@ error:
>
> /* mark as fallback mode */
> selinux_status = MAP_FAILED;
> - selinux_status_fd = avc_netlink_acquire_fd();
> last_seqno = (uint32_t)(-1);
>
> if (avc_using_threads)
> @@ -388,7 +385,5 @@ void selinux_status_close(void)
> munmap(selinux_status, pagesize);
> selinux_status = NULL;
>
> - close(selinux_status_fd);
> - selinux_status_fd = -1;
> last_seqno = (uint32_t)(-1);
> }
> --
> 2.30.0
>
ack and staged. I love a negative diffstat. Thanks Petr.
https://github.com/SELinuxProject/selinux/pull/279
