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 for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <15f5dff8217b1a2e16697d40e48dee6dd1f9b2f3.camel@intel.com>
Date:   Fri, 16 Jun 2023 16:16:28 +0000
From:   "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
To:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "rppt@...nel.org" <rppt@...nel.org>
CC:     "tglx@...utronix.de" <tglx@...utronix.de>,
        "mcgrof@...nel.org" <mcgrof@...nel.org>,
        "deller@....de" <deller@....de>,
        "davem@...emloft.net" <davem@...emloft.net>,
        "nadav.amit@...il.com" <nadav.amit@...il.com>,
        "linux@...linux.org.uk" <linux@...linux.org.uk>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "linux-mips@...r.kernel.org" <linux-mips@...r.kernel.org>,
        "linux-riscv@...ts.infradead.org" <linux-riscv@...ts.infradead.org>,
        "hca@...ux.ibm.com" <hca@...ux.ibm.com>,
        "catalin.marinas@....com" <catalin.marinas@....com>,
        "kent.overstreet@...ux.dev" <kent.overstreet@...ux.dev>,
        "puranjay12@...il.com" <puranjay12@...il.com>,
        "linux-s390@...r.kernel.org" <linux-s390@...r.kernel.org>,
        "palmer@...belt.com" <palmer@...belt.com>,
        "chenhuacai@...nel.org" <chenhuacai@...nel.org>,
        "tsbogend@...ha.franken.de" <tsbogend@...ha.franken.de>,
        "linux-trace-kernel@...r.kernel.org" 
        <linux-trace-kernel@...r.kernel.org>,
        "linux-parisc@...r.kernel.org" <linux-parisc@...r.kernel.org>,
        "christophe.leroy@...roup.eu" <christophe.leroy@...roup.eu>,
        "x86@...nel.org" <x86@...nel.org>,
        "mpe@...erman.id.au" <mpe@...erman.id.au>,
        "mark.rutland@....com" <mark.rutland@....com>,
        "rostedt@...dmis.org" <rostedt@...dmis.org>,
        "linuxppc-dev@...ts.ozlabs.org" <linuxppc-dev@...ts.ozlabs.org>,
        "will@...nel.org" <will@...nel.org>,
        "dinguyen@...nel.org" <dinguyen@...nel.org>,
        "naveen.n.rao@...ux.ibm.com" <naveen.n.rao@...ux.ibm.com>,
        "sparclinux@...r.kernel.org" <sparclinux@...r.kernel.org>,
        "linux-modules@...r.kernel.org" <linux-modules@...r.kernel.org>,
        "bpf@...r.kernel.org" <bpf@...r.kernel.org>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        "song@...nel.org" <song@...nel.org>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>,
        "loongarch@...ts.linux.dev" <loongarch@...ts.linux.dev>,
        "akpm@...ux-foundation.org" <akpm@...ux-foundation.org>
Subject: Re: [PATCH v2 04/12] mm/execmem, arch: convert remaining overrides of
 module_alloc to execmem

On Fri, 2023-06-16 at 11:50 +0300, Mike Rapoport wrote:
> -void *module_alloc(unsigned long size)
> -{
> -       gfp_t gfp_mask = GFP_KERNEL;
> -       void *p;
> -
> -       if (PAGE_ALIGN(size) > MODULES_LEN)
> -               return NULL;
> +static struct execmem_params execmem_params = {
> +       .modules = {
> +               .flags = EXECMEM_KASAN_SHADOW,
> +               .text = {
> +                       .alignment = MODULE_ALIGN,
> +               },
> +       },
> +};

Did you consider making these execmem_params's ro_after_init? Not that
it is security sensitive, but it's a nice hint to the reader that it is
only modified at init. And I guess basically free sanitizing of buggy
writes to it.

>  
> -       p = __vmalloc_node_range(size, MODULE_ALIGN,
> -                                MODULES_VADDR +
> get_module_load_offset(),
> -                                MODULES_END, gfp_mask, PAGE_KERNEL,
> -                                VM_FLUSH_RESET_PERMS |
> VM_DEFER_KMEMLEAK,
> -                                NUMA_NO_NODE,
> __builtin_return_address(0));
> +struct execmem_params __init *execmem_arch_params(void)
> +{
> +       unsigned long start = MODULES_VADDR +
> get_module_load_offset();

I think we can drop the mutex's in get_module_load_offset() now, since
execmem_arch_params() should only be called once at init.

>  
> -       if (p && (kasan_alloc_module_shadow(p, size, gfp_mask) < 0))
> {
> -               vfree(p);
> -               return NULL;
> -       }
> +       execmem_params.modules.text.start = start;
> +       execmem_params.modules.text.end = MODULES_END;
> +       execmem_params.modules.text.pgprot = PAGE_KERNEL;
>  
> -       return p;
> +       return &execmem_params;
>  }
>  

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ