Re: [Qemu-devel] [PATCH v6 4/8] linux-user/syscall: Introduce target_sockaddr_nl

2019-09-12 Thread Laurent Vivier 
Le 11/09/2019 à 21:34, Philippe Mathieu-Daudé a écrit :
> On Mon, Sep 9, 2019 at 4:23 PM Laurent Vivier  wrote:
>> Le 08/09/2019 à 08:15, Philippe Mathieu-Daudé a écrit :
>>> Signed-off-by: Philippe Mathieu-Daudé 
>>> Tested-By: Guido Günther 
>>> ---
>>>  linux-user/syscall.c  | 6 --
>>>  linux-user/syscall_defs.h | 7 +++
>>>  2 files changed, 11 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
>>> index 8b41a03901..5128312db5 100644
>>> --- a/linux-user/syscall.c
>>> +++ b/linux-user/syscall.c
>>> @@ -1494,8 +1494,10 @@ static inline abi_long 
>>> host_to_target_sockaddr(abi_ulong target_addr,
>>>  sizeof(target_saddr->sa_family)) {
>>>  target_saddr->sa_family = tswap16(addr->sa_family);
>>>  }
>>> -if (addr->sa_family == AF_NETLINK && len >= sizeof(struct 
>>> sockaddr_nl)) {
>>> -struct sockaddr_nl *target_nl = (struct sockaddr_nl *)target_saddr;
>>> +if (addr->sa_family == AF_NETLINK &&
>>> +len >= sizeof(struct target_sockaddr_nl)) {
>>> +struct target_sockaddr_nl *target_nl =
>>> +   (struct target_sockaddr_nl *)target_saddr;
>>>  target_nl->nl_pid = tswap32(target_nl->nl_pid);
>>>  target_nl->nl_groups = tswap32(target_nl->nl_groups);
>>>  } else if (addr->sa_family == AF_PACKET) {
>>> diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
>>> index 0662270300..fcedd0d0fb 100644
>>> --- a/linux-user/syscall_defs.h
>>> +++ b/linux-user/syscall_defs.h
>>> @@ -153,6 +153,13 @@ struct target_sockaddr_un {
>>>  uint8_t sun_path[108];
>>>  };
>>>
>>> +struct target_sockaddr_nl {
>>> +uint16_t nl_family; /* AF_NETLINK */
>>> +uint16_t __pad;
>>> +uint32_t nl_pid;
>>> +uint32_t nl_groups;
>>> +};
>>
>> You should use abi_ushort and abi_uint to keep alignments good (for
>> instance m68k aligns on 16bit whereas others on 32bit).
> 
> Are you sure? The other target_sockaddr don't use that...
> Is this because netlink is a host-only structure? (while other are
> serialized over some interface).

I think other target_sockaddr are wrong too. No one takes really care of
alignment, and most of the time structures are by construction well aligned.

Thanks,
Laurent

Re: [Qemu-devel] [PATCH v6 4/8] linux-user/syscall: Introduce target_sockaddr_nl

2019-09-11 Thread Philippe Mathieu-Daudé 
On Mon, Sep 9, 2019 at 4:23 PM Laurent Vivier  wrote:
> Le 08/09/2019 à 08:15, Philippe Mathieu-Daudé a écrit :
> > Signed-off-by: Philippe Mathieu-Daudé 
> > Tested-By: Guido Günther 
> > ---
> >  linux-user/syscall.c  | 6 --
> >  linux-user/syscall_defs.h | 7 +++
> >  2 files changed, 11 insertions(+), 2 deletions(-)
> >
> > diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> > index 8b41a03901..5128312db5 100644
> > --- a/linux-user/syscall.c
> > +++ b/linux-user/syscall.c
> > @@ -1494,8 +1494,10 @@ static inline abi_long 
> > host_to_target_sockaddr(abi_ulong target_addr,
> >  sizeof(target_saddr->sa_family)) {
> >  target_saddr->sa_family = tswap16(addr->sa_family);
> >  }
> > -if (addr->sa_family == AF_NETLINK && len >= sizeof(struct 
> > sockaddr_nl)) {
> > -struct sockaddr_nl *target_nl = (struct sockaddr_nl *)target_saddr;
> > +if (addr->sa_family == AF_NETLINK &&
> > +len >= sizeof(struct target_sockaddr_nl)) {
> > +struct target_sockaddr_nl *target_nl =
> > +   (struct target_sockaddr_nl *)target_saddr;
> >  target_nl->nl_pid = tswap32(target_nl->nl_pid);
> >  target_nl->nl_groups = tswap32(target_nl->nl_groups);
> >  } else if (addr->sa_family == AF_PACKET) {
> > diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
> > index 0662270300..fcedd0d0fb 100644
> > --- a/linux-user/syscall_defs.h
> > +++ b/linux-user/syscall_defs.h
> > @@ -153,6 +153,13 @@ struct target_sockaddr_un {
> >  uint8_t sun_path[108];
> >  };
> >
> > +struct target_sockaddr_nl {
> > +uint16_t nl_family; /* AF_NETLINK */
> > +uint16_t __pad;
> > +uint32_t nl_pid;
> > +uint32_t nl_groups;
> > +};
>
> You should use abi_ushort and abi_uint to keep alignments good (for
> instance m68k aligns on 16bit whereas others on 32bit).

Are you sure? The other target_sockaddr don't use that...
Is this because netlink is a host-only structure? (while other are
serialized over some interface).

Thanks,

Phil.

Re: [Qemu-devel] [PATCH v6 4/8] linux-user/syscall: Introduce target_sockaddr_nl

2019-09-09 Thread Laurent Vivier 
Le 08/09/2019 à 08:15, Philippe Mathieu-Daudé a écrit :
> Signed-off-by: Philippe Mathieu-Daudé 
> Tested-By: Guido Günther 
> ---
>  linux-user/syscall.c  | 6 --
>  linux-user/syscall_defs.h | 7 +++
>  2 files changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 8b41a03901..5128312db5 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -1494,8 +1494,10 @@ static inline abi_long 
> host_to_target_sockaddr(abi_ulong target_addr,
>  sizeof(target_saddr->sa_family)) {
>  target_saddr->sa_family = tswap16(addr->sa_family);
>  }
> -if (addr->sa_family == AF_NETLINK && len >= sizeof(struct sockaddr_nl)) {
> -struct sockaddr_nl *target_nl = (struct sockaddr_nl *)target_saddr;
> +if (addr->sa_family == AF_NETLINK &&
> +len >= sizeof(struct target_sockaddr_nl)) {
> +struct target_sockaddr_nl *target_nl =
> +   (struct target_sockaddr_nl *)target_saddr;
>  target_nl->nl_pid = tswap32(target_nl->nl_pid);
>  target_nl->nl_groups = tswap32(target_nl->nl_groups);
>  } else if (addr->sa_family == AF_PACKET) {
> diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
> index 0662270300..fcedd0d0fb 100644
> --- a/linux-user/syscall_defs.h
> +++ b/linux-user/syscall_defs.h
> @@ -153,6 +153,13 @@ struct target_sockaddr_un {
>  uint8_t sun_path[108];
>  };
>  
> +struct target_sockaddr_nl {
> +uint16_t nl_family; /* AF_NETLINK */
> +uint16_t __pad;
> +uint32_t nl_pid;
> +uint32_t nl_groups;
> +};

You should use abi_ushort and abi_uint to keep alignments good (for
instance m68k aligns on 16bit whereas others on 32bit).

Thanks,
Laurent

[Qemu-devel] [PATCH v6 4/8] linux-user/syscall: Introduce target_sockaddr_nl

2019-09-08 Thread Philippe Mathieu-Daudé 
Signed-off-by: Philippe Mathieu-Daudé 
Tested-By: Guido Günther 
---
 linux-user/syscall.c  | 6 --
 linux-user/syscall_defs.h | 7 +++
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 8b41a03901..5128312db5 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -1494,8 +1494,10 @@ static inline abi_long host_to_target_sockaddr(abi_ulong 
target_addr,
 sizeof(target_saddr->sa_family)) {
 target_saddr->sa_family = tswap16(addr->sa_family);
 }
-if (addr->sa_family == AF_NETLINK && len >= sizeof(struct sockaddr_nl)) {
-struct sockaddr_nl *target_nl = (struct sockaddr_nl *)target_saddr;
+if (addr->sa_family == AF_NETLINK &&
+len >= sizeof(struct target_sockaddr_nl)) {
+struct target_sockaddr_nl *target_nl =
+   (struct target_sockaddr_nl *)target_saddr;
 target_nl->nl_pid = tswap32(target_nl->nl_pid);
 target_nl->nl_groups = tswap32(target_nl->nl_groups);
 } else if (addr->sa_family == AF_PACKET) {
diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
index 0662270300..fcedd0d0fb 100644
--- a/linux-user/syscall_defs.h
+++ b/linux-user/syscall_defs.h
@@ -153,6 +153,13 @@ struct target_sockaddr_un {
 uint8_t sun_path[108];
 };
 
+struct target_sockaddr_nl {
+uint16_t nl_family; /* AF_NETLINK */
+uint16_t __pad;
+uint32_t nl_pid;
+uint32_t nl_groups;
+};
+
 struct target_in_addr {
 uint32_t s_addr; /* big endian */
 };
-- 
2.20.1