From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 883DE8D0039 for ; Fri, 25 Feb 2011 13:00:30 -0500 (EST) Date: Fri, 25 Feb 2011 18:52:02 +0100 From: Oleg Nesterov Subject: [PATCH 0/4 RESEND] exec: unify compat/non-compat code Message-ID: <20110225175202.GA19059@redhat.com> References: <20101130200129.GG11905@redhat.com> <20101201182747.GB6143@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20101201182747.GB6143@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: KOSAKI Motohiro , Linus Torvalds , LKML , linux-mm , pageexec@freemail.hu, Solar Designer , Eugene Teo , Brad Spengler , Roland McGrath , Milton Miller On 12/01, Oleg Nesterov wrote: > > On 12/01, Milton Miller wrote: > > > > > +#ifdef CONFIG_COMPAT > > > +int compat_do_execve(char * filename, > > > + compat_uptr_t __user *argv, > > > + compat_uptr_t __user *envp, > > > + struct pt_regs * regs) > > > +{ > > > + return do_execve_common(filename, > > > + (void __user*)argv, (void __user*)envp, > > > > Shouldn't these be compat_ptr(argv)? (makes a difference on s390) > > I'll recheck, but I don't think so. Please note that compat_ptr() > accepts "compat_uptr_t", not "compat_uptr_t *". > > argv should be correct as a pointer to user-space, otherwise the > current code is buggy. For example, compat_do_execve() passes > argv to compat_count() which does get_user(argv) without any > conversion. So, once again, this should not (and can not) be compat_ptr(argv) afaics. I don't understand the s390 asm, but compat_wrapper.S:sys32_execve_wrapper looks correct. If not, the current code is already buggy and s390 should be fixed. argv/envp are not compat ptrs, they just point to compat_ data, we should not do any conversion. I am resending this series unchanged, plus the trivial 5/5 to document acct_arg_size(). ---------------------------------------------------------------------- execve code in fs/compat.c must die. It is very hard to maintain this copy-and-paste horror. And the only reason for this duplication is that argv/envp point to char* or compat_uptr_t depending on compat. We can add the trivial helper which hides the difference and unify the code. Oleg. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org