From: Mark Hairgrove <mhairgrove@xxxxxxxxxx> Subject: mm/migrate: fix indexing bug (off by one) and avoid out of bound access Index was incremented before last use and thus the second array could dereference to an invalid address (not mentioning the fact that it did not properly clear the entry we intended to clear). Link: http://lkml.kernel.org/r/1506973525-16491-1-git-send-email-jglisse@xxxxxxxxxx Fixes: 8315ada7f095bf ("mm/migrate: allow migrate_vma() to alloc new page on empty entry") Signed-off-by: Mark Hairgrove <mhairgrove@xxxxxxxxxx> Signed-off-by: Jérôme Glisse <jglisse@xxxxxxxxxx> Cc: Reza Arbab <arbab@xxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/migrate.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff -puN mm/migrate.c~mm-migrate-fix-indexing-bug-off-by-one-and-avoid-out-of-bound-access mm/migrate.c --- a/mm/migrate.c~mm-migrate-fix-indexing-bug-off-by-one-and-avoid-out-of-bound-access +++ a/mm/migrate.c @@ -2146,8 +2146,9 @@ static int migrate_vma_collect_hole(unsi unsigned long addr; for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) { - migrate->src[migrate->npages++] = MIGRATE_PFN_MIGRATE; + migrate->src[migrate->npages] = MIGRATE_PFN_MIGRATE; migrate->dst[migrate->npages] = 0; + migrate->npages++; migrate->cpages++; } _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
