From 029b85fe417c36b5689093dd4861c7980299a50f Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Sun, 13 Aug 2023 19:34:02 -0400 Subject: [PATCH] bcachefs: Fix bkey format calculation For extents, we increase the number of bits of the size field to allow extents to get bigger due to merging - but this code didn't check for overflow. Signed-off-by: Kent Overstreet --- fs/bcachefs/bkey.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/bcachefs/bkey.c b/fs/bcachefs/bkey.c index d6960e259c80..0a5bfe6e9a2d 100644 --- a/fs/bcachefs/bkey.c +++ b/fs/bcachefs/bkey.c @@ -591,8 +591,10 @@ struct bkey_format bch2_bkey_format_done(struct bkey_format_state *s) /* allow for extent merging: */ if (ret.bits_per_field[BKEY_FIELD_SIZE]) { - ret.bits_per_field[BKEY_FIELD_SIZE] += 4; - bits += 4; + unsigned b = min(4U, 32U - ret.bits_per_field[BKEY_FIELD_SIZE]); + + ret.bits_per_field[BKEY_FIELD_SIZE] += b; + bits += b; } ret.key_u64s = DIV_ROUND_UP(bits, 64);