Re: [Qemu-devel] [PATCH] Fix getgroups() syscall emulation

[Riku Voipio <riku.voipio@iki.fi>]

On Thu, Sep 18, 2008 at 06:07:00PM +0300, Kirill A. Shutemov wrote:
> According to man page getgroups(2):
> 
> If size is zero, list is not modified, but the total number of
> supplementary group IDs for the process is returned.

Looks ok to me.

> Signed-off-by: Kirill A. Shutemov <kirill@shutemov.name>
> ---
>  linux-user/syscall.c |    4 ++++
>  1 files changed, 4 insertions(+), 0 deletions(-)
> 
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 124d14e..948ea3b 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -5247,6 +5247,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
>  
>              grouplist = alloca(gidsetsize * sizeof(gid_t));
>              ret = get_errno(getgroups(gidsetsize, grouplist));
> +            if (gidsetsize == 0)
> +                break;
>              if (!is_error(ret)) {
>                  target_grouplist = lock_user(VERIFY_WRITE, arg2, gidsetsize * 2, 0);
>                  if (!target_grouplist)
> @@ -5397,6 +5399,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
>  
>              grouplist = alloca(gidsetsize * sizeof(gid_t));
>              ret = get_errno(getgroups(gidsetsize, grouplist));
> +            if (gidsetsize == 0)
> +                break;
>              if (!is_error(ret)) {
>                  target_grouplist = lock_user(VERIFY_WRITE, arg2, gidsetsize * 4, 0);
>                  if (!target_grouplist) {
> -- 
> 1.5.6.5.GIT
> 
> 

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