On Thu, May 11, 2023 at 9:33 AM Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx> wrote: > > On Thu, May 11, 2023 at 03:25:06PM +0200, Alexander Mikhalitsyn wrote: > > Implement ->bpf_bypass_getsockopt proto callback and filter out > > SCTP_SOCKOPT_PEELOFF, SCTP_SOCKOPT_PEELOFF_FLAGS and SCTP_SOCKOPT_CONNECTX3 > > socket options from running eBPF hook on them. > > > > SCTP_SOCKOPT_PEELOFF and SCTP_SOCKOPT_PEELOFF_FLAGS options do fd_install(), > > and if BPF_CGROUP_RUN_PROG_GETSOCKOPT hook returns an error after success of > > the original handler sctp_getsockopt(...), userspace will receive an error > > from getsockopt syscall and will be not aware that fd was successfully > > installed into a fdtable. > > > > As pointed by Marcelo Ricardo Leitner it seems reasonable to skip > > bpf getsockopt hook for SCTP_SOCKOPT_CONNECTX3 sockopt too. > > Because internaly, it triggers connect() and if error is masked > > then userspace will be confused. > > > > This patch was born as a result of discussion around a new SCM_PIDFD interface: > > https://lore.kernel.org/all/20230413133355.350571-3-aleksandr.mikhalitsyn@xxxxxxxxxxxxx/ > > > > Fixes: 0d01da6afc54 ("bpf: implement getsockopt and setsockopt hooks") > > Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx> > > Cc: Christian Brauner <brauner@xxxxxxxxxx> > > Cc: Stanislav Fomichev <sdf@xxxxxxxxxx> > > Cc: Neil Horman <nhorman@xxxxxxxxxxxxx> > > Cc: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx> > > Cc: Xin Long <lucien.xin@xxxxxxxxx> > > Cc: linux-sctp@xxxxxxxxxxxxxxx > > Cc: linux-kernel@xxxxxxxxxxxxxxx > > Cc: netdev@xxxxxxxxxxxxxxx > > Suggested-by: Stanislav Fomichev <sdf@xxxxxxxxxx> > > Acked-by: Stanislav Fomichev <sdf@xxxxxxxxxx> > > Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@xxxxxxxxxxxxx> > > Thx! > > Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx> Acked-by: Xin Long <lucien.xin@xxxxxxxxx>
