Re: [PATCH v2] kernel/fork: stop playing lockless games for exe_file replacement

From: Oleg Nesterov
Date: Mon Aug 14 2023 - 14:13:39 EST


On 08/14, Mateusz Guzik wrote:
>
> However, fe69d560b5bd ("kernel/fork: always deny write access to current
> MM exe_file") added a semaphore up/down cycle to synchronize the state
> of exe_file against fork, defeating the point of the original change.

Agreed,

> Signed-off-by: Mateusz Guzik <mjguzik@xxxxxxxxx>
> ---
> fs/exec.c | 4 ++--
> kernel/fork.c | 22 +++++++++-------------
> 2 files changed, 11 insertions(+), 15 deletions(-)

Acked-by: Oleg Nesterov <oleg@xxxxxxxxxx>