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| author | Kent Overstreet <kent.overstreet@gmail.com> | 2022-03-28 12:31:22 -0400 |
|---|---|---|
| committer | Kent Overstreet <kent.overstreet@gmail.com> | 2022-04-17 15:44:28 -0400 |
| commit | 6fbdbb2aee90e8c8c5441c4bc3fa63803b91ada4 (patch) | |
| tree | e6b3e2f9f08692f4d2a3e577f8b6aa2cf332c125 | |
| parent | fc91fb4889d7302b2216da3867a0afa2962759a1 (diff) | |
bcachefs: Heap code fix
When deleting an entry from a heap that was at entry h->used - 1, we'd
end up calling heap_sift() on an entry outside the heap - the entry we
just removed - which would end up re-adding it to the heap and deleting
something we didn't want to delete. Oops...
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
| -rw-r--r-- | fs/bcachefs/util.h | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/fs/bcachefs/util.h b/fs/bcachefs/util.h index aa56c94d6bd1..888693703c75 100644 --- a/fs/bcachefs/util.h +++ b/fs/bcachefs/util.h @@ -210,9 +210,11 @@ do { \ \ BUG_ON(_i >= (h)->used); \ (h)->used--; \ - heap_swap(h, _i, (h)->used, set_backpointer); \ - heap_sift_up(h, _i, cmp, set_backpointer); \ - heap_sift_down(h, _i, cmp, set_backpointer); \ + if ((_i) < (h)->used) { \ + heap_swap(h, _i, (h)->used, set_backpointer); \ + heap_sift_up(h, _i, cmp, set_backpointer); \ + heap_sift_down(h, _i, cmp, set_backpointer); \ + } \ } while (0) #define heap_pop(h, d, cmp, set_backpointer) \ |