linux-kernel - Re: [PATCH v2] alpha/elf: Fix misc/setarch test of util-linux by removing 32bit support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <Z5eJ2p5IeNzPDuVH@minute>
Date: Mon, 27 Jan 2025 14:27:54 +0100
From: Ivan Kokshaysky <ink@...een.parts>
To: John Paul Adrian Glaubitz <glaubitz@...sik.fu-berlin.de>
Cc: "Eric W. Biederman" <ebiederm@...ssion.com>,
	"Maciej W. Rozycki" <macro@...am.me.uk>,
	Arnd Bergmann <arnd@...db.de>,
	Richard Henderson <richard.henderson@...aro.org>,
	Matt Turner <mattst88@...il.com>, Kees Cook <kees@...nel.org>,
	"Paul E. McKenney" <paulmck@...nel.org>,
	linux-alpha@...r.kernel.org, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org, Michael Cree <mcree@...on.net.nz>,
	Sam James <sam@...too.org>,
	Geert Uytterhoeven <geert@...ux-m68k.org>,
	Michael Karcher <kernel@...rcher.dialup.fu-berlin.de>,
	Chris Hofstaedtler <zeha@...ian.org>, util-linux@...r.kernel.org,
	linux-mips@...r.kernel.org, loongarch@...ts.linux.dev
Subject: Re: [PATCH v2] alpha/elf: Fix misc/setarch test of util-linux by
 removing 32bit support

On Sun, Jan 26, 2025 at 06:15:43PM +0100, John Paul Adrian Glaubitz wrote:
> Hi Eric,
> 
> On Sat, 2025-01-18 at 11:35 +0100, Ivan Kokshaysky wrote:
> > On Sun, Jan 12, 2025 at 11:39:01PM -0600, Eric W. Biederman wrote:
> > ...
> > > --- a/arch/alpha/include/asm/pgtable.h
> > > +++ b/arch/alpha/include/asm/pgtable.h
> > > @@ -360,7 +360,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
> > >  
> > >  extern void paging_init(void);
> > >  
> > > -/* We have our own get_unmapped_area to cope with ADDR_LIMIT_32BIT.  */
> > > +/* We have our own get_unmapped_area */
> > >  #define HAVE_ARCH_UNMAPPED_AREA
> > 
> > Just remove the definition. As the comment suggests, the only reason
> > it exists is ADDR_LIMIT_32BIT, which is gone.
> > 
> > > --- a/arch/alpha/kernel/osf_sys.c
> > > +++ b/arch/alpha/kernel/osf_sys.c
> > > @@ -1210,8 +1210,7 @@ SYSCALL_DEFINE1(old_adjtimex, struct timex32 __user *, txc_p)
> > >  	return ret;
> > >  }
> > >  
> > > -/* Get an address range which is currently unmapped.  Similar to the
> > > -   generic version except that we know how to honor ADDR_LIMIT_32BIT.  */
> > > +/* Get an address range which is currently unmapped. */
> > >  
> > >  static unsigned long
> > >  arch_get_unmapped_area_1(unsigned long addr, unsigned long len,
> > > @@ -1230,13 +1229,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
> > >  		       unsigned long len, unsigned long pgoff,
> > >  		       unsigned long flags, vm_flags_t vm_flags)
> > >  {
> > > -	unsigned long limit;
> > > -
> > > -	/* "32 bit" actually means 31 bit, since pointers sign extend.  */
> > > -	if (current->personality & ADDR_LIMIT_32BIT)
> > > -		limit = 0x80000000;
> > > -	else
> > > -		limit = TASK_SIZE;
> > > +	unsigned long limit = TASK_SIZE;
> > >  
> > >  	if (len > limit)
> > >  		return -ENOMEM;
> > 
> > Likewise, just remove these functions. The generic_get_unmapped_area()
> > works fine, tested on up1500.
> 
> Can you send a follow-up integrating those changes? It would be good if
> SET_PERSONALITY() could be fixed on alpha for v6.14.

Oh, the changes I proposed are mere cleanup suggestions.
The original patch would do just fine.

Ivan.