One common problem with 32 bit system call and ioctl emulation is the
different alignment rules between i386 and 64 bit machines. A number of
drivers work around this by marking the compat structures as
'attribute((packed))', which is not the right solution because it breaks
all the non-x86 architectures that want to use the same compat code.
Hopefully, this patch improves the situation, it introduces two new types,
compat_u64 and compat_s64. These are defined on all architectures to have
the same size and alignment as the 32 bit version of u64 and s64.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Vasily Tarasov <vtaras@openvz.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Otherwise we get a ton of unaligned exceptions, for cases such
as compat_sys_msgrcv() which go:
p = compat_alloc_user_space(second + sizeof(struct msgbuf));
and here 'second' can for example be an arbitrary odd value.
Based upon a bug report from Jurij Smakov.
Signed-off-by: David S. Miller <davem@davemloft.net>
When I first wrote the compat layer patches, I was somewhat cavalier about
the definition of compat_uid_t and compat_gid_t (or maybe I just
misunderstood :-)). This patch makes the compat types much more consistent
with the types we are being compatible with and hopefully will fix a few
bugs along the way.
compat type type in compat arch
__compat_[ug]id_t __kernel_[ug]id_t
__compat_[ug]id32_t __kernel_[ug]id32_t
compat_[ug]id_t [ug]id_t
The difference is that compat_uid_t is always 32 bits (for the archs we
care about) but __compat_uid_t may be 16 bits on some.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch is based on work by Carlos O'Donell and Matthew Wilcox. It
introduces/updates the compat_time_t type and uses it for compat siginfo
structures. I have built this on ppc64 and x86_64.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Like Alpha, sparc64's struct stat was defined before we had the
nanosecond et al. fields added. So like Alpha I have to cons up a
struct stat64 to get this stuff. I'll work on the glibc bits soon.
Also, we were forgetting to fill in the nanosecond fields in the sparc
compat stat64 syscalls.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
