Re: [Qemu-devel] [PATCH] linux-user: syscall: Add SO_LINGER for setsockopt

[Laurent Vivier]

Le 08/01/2016 03:03, address@hidden a écrit :
> From: Chen Gang <address@hidden>
> 
> Just implement it according to the other features implementations.
> 
> Signed-off-by: Chen Gang <address@hidden>
> ---
>  linux-user/syscall.c      | 16 +++++++++++++++-
>  linux-user/syscall_defs.h |  5 +++++
>  2 files changed, 20 insertions(+), 1 deletion(-)
> 
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index f27148a..9f2c871 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -1409,6 +1409,9 @@ static abi_long do_setsockopt(int sockfd, int level, 
> int optname,
>      int val;
>      struct ip_mreqn *ip_mreq;
>      struct ip_mreq_source *ip_mreq_source;
> +    struct linger lg;
> +    struct target_linger *tlg;
> +
>  
>      switch(level) {
>      case SOL_TCP:
> @@ -1659,7 +1662,19 @@ set_timeout:
>          case TARGET_SO_RCVLOWAT:
>               optname = SO_RCVLOWAT;
>               break;
> -            break;
> +        case TARGET_SO_LINGER:
> +            optname = SO_LINGER;
> +            if (optlen != sizeof(struct target_linger)) {
> +                return -TARGET_EINVAL;
> +            }

OK, this time you're right, there is this check in the kernel too...
and optlen is really the length for setsockopt(), not a pointer.

> +            if (!lock_user_struct(VERIFY_READ, tlg, optval_addr, 1)) {
> +                return -TARGET_EFAULT;
> +            }
> +            __get_user(lg.l_onoff, &tlg->l_onoff);
> +            __get_user(lg.l_linger, &tlg->l_linger);
> +            unlock_user_struct(tlg, optval_addr, 0);

You can't unlock the structure you're going to use.

> +            return get_errno(setsockopt(sockfd, SOL_SOCKET, optname,
> +                             &lg, sizeof(lg)));

Why do you use "SOL_SOCKET" instead of "level" ?

>          default:
>              goto unimplemented;
>          }
> diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
> index 9d3c537..5a4d565 100644
> --- a/linux-user/syscall_defs.h
> +++ b/linux-user/syscall_defs.h
> @@ -165,6 +165,11 @@ struct target_ip_mreq_source {
>      uint32_t imr_sourceaddr;
>  };
>  
> +struct target_linger {
> +    int l_onoff;        /* Linger active                */
> +    int l_linger;       /* How long to linger for       */
> +};
> +

Must be "abi_int" to force good alignment for the target.

>  struct target_timeval {
>      abi_long tv_sec;
>      abi_long tv_usec;
>