Le 06/01/2022 à 23:00, Patrick Venture a écrit :
> From: Shu-Chun Weng <scw@google.com>
>
> Linux kernel does it this way (checks read permission before validating `how`)
> and the latest version of ABSL's `AddressIsReadable()` depends on this
> behavior.
>
> c.f. https://github.com/torvalds/linux/blob/9539ba4308ad5bdca6cb41c7b73cbb9f796dcdd7/kernel/signal.c#L3147
> Reviewed-by: Patrick Venture <venture@google.com>
> Signed-off-by: Shu-Chun Weng <scw@google.com>
> ---
> linux-user/syscall.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index ce9d64896c..3070d31f34 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -9491,6 +9491,11 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
> }
>
> if (arg2) {
> + if (!(p = lock_user(VERIFY_READ, arg2, sizeof(target_sigset_t), 1)))
> + return -TARGET_EFAULT;
> + target_to_host_sigset(&set, p);
> + unlock_user(p, arg2, 0);
> + set_ptr = &set;
> switch(how) {
> case TARGET_SIG_BLOCK:
> how = SIG_BLOCK;
> @@ -9504,11 +9509,6 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
> default:
> return -TARGET_EINVAL;
> }
> - if (!(p = lock_user(VERIFY_READ, arg2, sizeof(target_sigset_t), 1)))
> - return -TARGET_EFAULT;
> - target_to_host_sigset(&set, p);
> - unlock_user(p, arg2, 0);
> - set_ptr = &set;
> } else {
> how = 0;
> set_ptr = NULL;
I know it's only code move but generally we also update the style to pass scripts/checkpatch.pl
successfully.
That is a reasonable request, however, can I just send a follow-on patch? I didn't write this one and I honestly don't know much about it, but I don't mind doing the cleanup
Could you also update TARGET_NR_sigprocmask in the same way as it seems the kernel behaves like this
too in this case?
I can take a look. I would prefer then to also prefetch the style fixup in a preceding patch. I don't recall seeing whether qemu supports clang-format.
Thanks,
Laurent
Patrick