summaryrefslogtreecommitdiff
path: root/lib/decompress_unlzo.c
diff options
context:
space:
mode:
authorMel Gorman <mel@csn.ul.ie>2010-04-23 13:17:56 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2010-04-24 11:31:25 -0700
commit23be7468e8802a2ac1de6ee3eecb3ec7f14dc703 (patch)
tree2c01e547594b8d7f32ddda47b6bea284d8f19761 /lib/decompress_unlzo.c
parent9a6a1ecd9e9b5d046a236da2f7eb6b6812f04229 (diff)
hugetlb: fix infinite loop in get_futex_key() when backed by huge pages
If a futex key happens to be located within a huge page mapped MAP_PRIVATE, get_futex_key() can go into an infinite loop waiting for a page->mapping that will never exist. See https://bugzilla.redhat.com/show_bug.cgi?id=552257 for more details about the problem. This patch makes page->mapping a poisoned value that includes PAGE_MAPPING_ANON mapped MAP_PRIVATE. This is enough for futex to continue but because of PAGE_MAPPING_ANON, the poisoned value is not dereferenced or used by futex. No other part of the VM should be dereferencing the page->mapping of a hugetlbfs page as its page cache is not on the LRU. This patch fixes the problem with the test case described in the bugzilla. [akpm@linux-foundation.org: mel cant spel] Signed-off-by: Mel Gorman <mel@csn.ul.ie> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Darren Hart <darren@dvhart.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/decompress_unlzo.c')
0 files changed, 0 insertions, 0 deletions