On Thu, Dec 12, 2019 at 05:25:13PM +0100, Daniel Borkmann wrote:
On Tue, Dec 10, 2019 at 01:28:34PM -0800, Jakub Kicinski wrote:On Tue, 10 Dec 2019 16:07:11 -0500, Sasha Levin wrote: > From: Andrii Nakryiko <andriin@xxxxxx> > > [ Upstream commit 1e0bd5a091e5d9e0f1d5b0e6329b87bb1792f784 ] > > 92117d8443bc ("bpf: fix refcnt overflow") turned refcounting of bpf_map into > potentially failing operation, when refcount reaches BPF_MAX_REFCNT limit > (32k). Due to using 32-bit counter, it's possible in practice to overflow > refcounter and make it wrap around to 0, causing erroneous map free, while > there are still references to it, causing use-after-free problems. I don't think this is a bug fix, the second sentence here is written in a quite confusing way, but there is no bug. Could you drop? I don't think it's worth the backporting pain since it changes bpf_map_inc().Agree, this is not a bug fix and should not go to stable. (Also agree that the changelog is super confusing here and should have been done differently to avoid exactly where we are here. I think I pointed that out in the original patch, but seems this slipped through the cracks :/)
Sure, dropped, thanks! -- Thanks, Sasha
