Re: [PATCH] linux-user: make sure brk(0) returns a page-aligned value

[Richard Henderson]

On 7/6/23 12:34, Andreas Schwab wrote:
> Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
> Signed-off-by: Andreas Schwab <schwab@suse.de>
> ---
>   linux-user/syscall.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 08162cc966..e8a17377f5 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -805,7 +805,7 @@ static abi_ulong brk_page;
>   
>   void target_set_brk(abi_ulong new_brk)
>   {
> -    target_brk = new_brk;
> +    target_brk = TARGET_PAGE_ALIGN(new_brk);
>       brk_page = HOST_PAGE_ALIGN(target_brk);
>   }
>   

It make sense, since that's how do_brk aligns things.
I'm curious why this error might have produced host memory clobbering, but I'm not going 
to debug that.

Queuing for tcg/linux-user.


r~