From 61eea521fef11c6878a4157bcc0fca6e981a58b2 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Wed, 13 Nov 2019 10:30:05 +0900 Subject: [PATCH] fsmonitor: do not compare bitmap size with size of split index 3444ec2e ("fsmonitor: don't fill bitmap with entries to be removed", 2019-10-11) added a handful of sanity checks that make sure that a bit position in fsmonitor bitmap does not go beyond the end of the index. As each bit in the bitmap corresponds to a path in the index, this is the right check most of the time. Except for the case when we are in the split-index mode and looking at a delta index that is to be overlayed on the base index but before the base index has actually been merged in, namely in read_ and write_fsmonitor_extension(). In these codepaths, the entries in the split/delta index is typically a small subset of the entire set of paths (otherwise why would we be using split-index?), so the bitmap used by the fsmonitor is almost always larger than the number of entries in the partial index, and the incorrect comparison would trigger the BUG(). Reported-by: Utsav Shah Helped-by: Kevin Willford Helped-by: William Baker Signed-off-by: Junio C Hamano --- fsmonitor.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fsmonitor.c b/fsmonitor.c index 1f4aa1b150..0477500b39 100644 --- a/fsmonitor.c +++ b/fsmonitor.c @@ -55,7 +55,8 @@ int read_fsmonitor_extension(struct index_state *istate, const void *data, } istate->fsmonitor_dirty = fsmonitor_dirty; - if (istate->fsmonitor_dirty->bit_size > istate->cache_nr) + if (!istate->split_index && + istate->fsmonitor_dirty->bit_size > istate->cache_nr) BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)", (uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr); @@ -83,7 +84,8 @@ void write_fsmonitor_extension(struct strbuf *sb, struct index_state *istate) uint32_t ewah_size = 0; int fixup = 0; - if (istate->fsmonitor_dirty->bit_size > istate->cache_nr) + if (!istate->split_index && + istate->fsmonitor_dirty->bit_size > istate->cache_nr) BUG("fsmonitor_dirty has more entries than the index (%"PRIuMAX" > %u)", (uintmax_t)istate->fsmonitor_dirty->bit_size, istate->cache_nr);