From mboxrd@z Thu Jan 1 00:00:00 1970 From: ldv@altlinux.org (Dmitry V. Levin) Date: Thu, 9 Mar 2017 02:41:54 +0300 Subject: Compat 32-bit syscall entry from 64-bit task!? In-Reply-To: References: <201201260032.57937.vda.linux@googlemail.com> <201201260209.54513.vda.linux@googlemail.com> Message-ID: <20170308234154.GA2352@altlinux.org> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org Hi, On Thu, Jan 26, 2012 at 07:03:43PM +0100, Denys Vlasenko wrote: > Hi Linus, > > On Thu, Jan 26, 2012 at 4:47 AM, Linus Torvalds > wrote: > >> Please look at strace source, get_scno() function, where > >> it reads syscall no and parameters. Let's see.... > >> - POWERPC: has 32-bit and 64-bit mode > >> - X86_64: has 32-bit and 64-bit mode > >> - IA64: has i386-compat mode > >> - ARM: has more than one ABI > >> - SPARC: has 32-bit and 64-bit mode > >> > >> Do you want to re-invent a different arch-specific way to report > >> syscall type for each of these arches? > > > > I think an arch-specific one is better than trying to make some > > generic one that is messy. > > > > As you say, many architectures have multiple system call ABIs. > > > > But they tend to be very *different* issues. They can be about > > multiple ABI's, as you mention, and even when they *look* similar > > (32-bit vs 64-bit ABI's) they are actually totally different issues. > > [skip] > > I don't have a particular attachment to my solution, > and I think we already talk about this problem for > far too long. > > Looks like nobody is _strongly_ opposed to your patch > which uses a few bits in eflags to report bitness > of the x86 syscall. > > Lets just do that already. If you commit it to kernel git, > I will immediately change strace accordingly. Is there any progress with this (or any alternative) solution? I see the kernel side has changed a bit, and the strace part is in a better shape than 5 years ago (although I'm biased of course), but I don't see any kernel interface that would allow strace to reliably recognize this 0x80 case. -- ldv -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 801 bytes Desc: not available URL: