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
| ||
|
Date: Fri, 13 Apr 2007 10:15:24 +1000 From: Nick Piggin <nickpiggin@...oo.com.au> To: Andrew Morton <akpm@...ux-foundation.org> CC: William Lee Irwin III <wli@...omorphy.com>, Matt Mackall <mpm@...enic.com>, linux-kernel@...r.kernel.org Subject: Re: [PATCH 0/13] maps: pagemap, kpagemap, and related cleanups Andrew Morton wrote: > On Thu, 12 Apr 2007 16:10:50 -0700 > William Lee Irwin III <wli@...omorphy.com> wrote: >>+ while (count > 0) { >>+ chunk = min_t(size_t, count, PAGE_SIZE); >>+ i = 0; >>+ >>+ if (pfn == -1) { >>+ page[0] = 0; >>+ page[1] = 0; >>+ ((char *)page)[0] = (ntohl(1) != 1); > > > OK. > > >>+ ((char *)page)[1] = PAGE_SHIFT; > > > OK. Shouldn't we just expose page size and endianness by other means? (another file or syscall). >>+ for (; i < 2 * chunk / KPMSIZE; i += 2, pfn++) { >>+ ppage = pfn_to_page(pfn); >>+ if (!ppage) { >>+ page[i] = 0; >>+ page[i + 1] = 0; >>+ } else { >>+ page[i] = ppage->flags; >>+ page[i + 1] = atomic_read(&ppage->_count); >>+ } >>+ } > > > Not a good idea to expose raw flags in this manner - it changes at the drop > of a hat. We'd need to also expose the kernel's PG_foo-to-bitnumber > mapping to make this viable. I don't think it is viable because that makes the flags part of the userspace ABI. I wonder what they are needed for. -- SUSE Labs, Novell Inc. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists