Re: stat64 wrong on sparc64 user

[Richard Henderson]

On 3/28/23 04:48, Luca Bonissi wrote:
> On qemu-sparc64 (userspace) the struct "target_stat64" is not correctly padded, so the 
> field st_rdev is not correctly aligned and will report wrong major/minor (e.g. for 
> /dev/zero it reports 0,0x10500000 instead of 1,5).
>
> Here patch to solve the issue (it also fixes incorrect size on some fields):
>
> --- qemu-20230327/linux-user/syscall_defs.h    2023-03-27 15:41:42.000000000 
> +0200
> +++ qemu-20230327/linux-user/syscall_defs.h.new    2023-03-27 
> 21:43:25.615115126 +0200
> @@ -1450,7 +1450,7 @@ struct target_stat {
>       unsigned int    st_dev;
>       abi_ulong    st_ino;
>       unsigned int    st_mode;
> -    unsigned int    st_nlink;
> +    short int    st_nlink;
>       unsigned int    st_uid;
>       unsigned int    st_gid;
>       unsigned int    st_rdev;
> @@ -1465,8 +1465,7 @@ struct target_stat {
>
>   #define TARGET_HAS_STRUCT_STAT64
>   struct target_stat64 {
> -    unsigned char    __pad0[6];
> -    unsigned short    st_dev;
> +    uint64_t    st_dev;

All use of the normal C types is wrong for target structs.
You must use abi_{short,int,long} etc.

Otherwise, you may not get the alignment you're expecting.


r~