> On Feb 25, 2020, at 4:40 PM, Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > In xfs_da3_path_shift() blk can be assigned to state->path.blk[-1] if > state->path.active is 1 (which is a valid state) when it tries to add an > entry > to a single dir leaf block and then to shift forward to see if > there's a sibling block that would be a better place to put the new > entry. This causes a KASAN warning given s/KASAN/UBSAN/ > negative array indices are > undefined behavior in C. In practice the warning is entirely harmless > given that blk is never dereference in this case, but it is still better > to fix up the warning and slightly improve the code. Agree. This is better. Darrick, do you need me to send a v3 for it or you could squash this in?
