| 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
| ||
|
Message-Id: <1461591350-28700-3-git-send-email-vbabka@suse.cz> Date: Mon, 25 Apr 2016 15:35:49 +0200 From: Vlastimil Babka <vbabka@...e.cz> To: Andrew Morton <akpm@...ux-foundation.org> Cc: linux-kernel@...r.kernel.org, linux-mm@...ck.org, Michal Hocko <mhocko@...e.com>, Joonsoo Kim <iamjoonsoo.kim@....com>, Hugh Dickins <hughd@...gle.com>, Rik van Riel <riel@...hat.com>, Vlastimil Babka <vbabka@...e.cz> Subject: [PATCH mmotm 2/3] mm, compaction: fix crash in get_pfnblock_flags_mask() from isolate_freepages(): In isolate_freepages(), low_pfn was mistakenly initialized to pageblock_start_pfn() instead of pageblock_end_pfn(), creating a possible underflow, as described by Hugh: There's a case when that "block_start_pfn -= pageblock_nr_pages" loop can pass through 0 and end up trying to access a pageblock before the start of the mem_map[]. Fixes: mmotm mm-compaction-wrap-calculating-first-and-last-pfn-of-pageblock.patch Reported-by: Hugh Dickins <hughd@...gle.com> Signed-off-by: Vlastimil Babka <vbabka@...e.cz> --- mm/compaction.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/compaction.c b/mm/compaction.c index 759c3ac73ced..6a49d1b35515 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -999,7 +999,7 @@ static void isolate_freepages(struct compact_control *cc) block_start_pfn = pageblock_start_pfn(cc->free_pfn); block_end_pfn = min(block_start_pfn + pageblock_nr_pages, zone_end_pfn(zone)); - low_pfn = pageblock_start_pfn(cc->migrate_pfn); + low_pfn = pageblock_end_pfn(cc->migrate_pfn); /* * Isolate free pages until enough are available to migrate the -- 2.8.1
Powered by blists - more mailing lists