From ef8db3679746792403589fb54fa0bbb9e13245dd Mon Sep 17 00:00:00 2001 From: John Lo Date: Wed, 4 Jul 2018 16:27:59 -0400 Subject: [PATCH] Fix clib_bitmap_next_clear() function when no clear bits left If the bitmap has no bit clear after the input bit position i, the function will return i even if its bit is set. Fix is to return the next bit just beyond the free bitmap. This can cause IP neighbor scan crash in ip_neighbor_scan() with a debug image. With production image, ip_neighbor_scan() may still function, AFAICT, with extra neighbor delete attempts for entries already deleted, until these entries are reused for new neighbors. Change-Id: If6422ef6f63908ea39651de4ccbd8cb0b294bd69 Signed-off-by: John Lo --- src/vppinfra/bitmap.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/src/vppinfra/bitmap.h b/src/vppinfra/bitmap.h index d6dfe86da0b..0e94d028ee3 100644 --- a/src/vppinfra/bitmap.h +++ b/src/vppinfra/bitmap.h @@ -728,6 +728,9 @@ clib_bitmap_next_clear (uword * ai, uword i) if (t) return log2_first_set (t) + i0 * BITS (ai[0]); } + + /* no clear bit left in bitmap, return bit just beyond bitmap */ + return (i0 + 1) * BITS (ai[0]); } return i; } -- 2.16.6