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* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2018-10-191-8/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | net/sched/cls_api.c has overlapping changes to a call to nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL to the 5th argument, and another (from 'net-next') added cb->extack instead of NULL to the 6th argument. net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to code which moved (to mr_table_dump)) in 'net-next'. Thanks to David Ahern for the heads up. Signed-off-by: David S. Miller <davem@davemloft.net>
| * xsk: do not call synchronize_net() under RCU read lockBjörn Töpel2018-10-111-8/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The XSKMAP update and delete functions called synchronize_net(), which can sleep. It is not allowed to sleep during an RCU read section. Instead we need to make sure that the sock sk_destruct (xsk_destruct) function is asynchronously called after an RCU grace period. Setting the SOCK_RCU_FREE flag for XDP sockets takes care of this. Fixes: fbfc504a24f5 ("bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP") Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
* | bpf: return EOPNOTSUPP when map lookup isn't supportedPrashant Bhole2018-10-101-1/+1
|/ | | | | | | | | | | | | | Return ERR_PTR(-EOPNOTSUPP) from map_lookup_elem() methods of below map types: - BPF_MAP_TYPE_PROG_ARRAY - BPF_MAP_TYPE_STACK_TRACE - BPF_MAP_TYPE_XSKMAP - BPF_MAP_TYPE_SOCKMAP/BPF_MAP_TYPE_SOCKHASH Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* bpf: fix redirect to map under tail callsDaniel Borkmann2018-08-181-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commits 109980b894e9 ("bpf: don't select potentially stale ri->map from buggy xdp progs") and 7c3001313396 ("bpf: fix ri->map_owner pointer on bpf_prog_realloc") tried to mitigate that buggy programs using bpf_redirect_map() helper call do not leave stale maps behind. Idea was to add a map_owner cookie into the per CPU struct redirect_info which was set to prog->aux by the prog making the helper call as a proof that the map is not stale since the prog is implicitly holding a reference to it. This owner cookie could later on get compared with the program calling into BPF whether they match and therefore the redirect could proceed with processing the map safely. In (obvious) hindsight, this approach breaks down when tail calls are involved since the original caller's prog->aux pointer does not have to match the one from one of the progs out of the tail call chain, and therefore the xdp buffer will be dropped instead of redirected. A way around that would be to fix the issue differently (which also allows to remove related work in fast path at the same time): once the life-time of a redirect map has come to its end we use it's map free callback where we need to wait on synchronize_rcu() for current outstanding xdp buffers and remove such a map pointer from the redirect info if found to be present. At that time no program is using this map anymore so we simply invalidate the map pointers to NULL iff they previously pointed to that instance while making sure that the redirect path only reads out the map once. Fixes: 97f91a7cf04f ("bpf: add bpf_redirect_map helper routine") Fixes: 109980b894e9 ("bpf: don't select potentially stale ri->map from buggy xdp progs") Reported-by: Sebastiano Miano <sebastiano.miano@polito.it> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* bpf: decouple btf from seq bpf fs dump and enable more mapsDaniel Borkmann2018-08-131-2/+1
| | | | | | | | | | | | | | | | | | | | | | Commit a26ca7c982cb ("bpf: btf: Add pretty print support to the basic arraymap") and 699c86d6ec21 ("bpf: btf: add pretty print for hash/lru_hash maps") enabled support for BTF and dumping via BPF fs for array and hash/lru map. However, both can be decoupled from each other such that regular BPF maps can be supported for attaching BTF key/value information, while not all maps necessarily need to dump via map_seq_show_elem() callback. The basic sanity check which is a prerequisite for all maps is that key/value size has to match in any case, and some maps can have extra checks via map_check_btf() callback, e.g. probing certain types or indicating no support in general. With that we can also enable retrieving BTF info for per-cpu map types and lpm. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com>
* xsk: clean up SPDX headersBjörn Töpel2018-05-181-9/+0
| | | | | | | Clean up SPDX-License-Identifier and removing licensing leftovers. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
* bpf, xskmap: fix crash in xsk_map_alloc error path handlingDaniel Borkmann2018-05-041-0/+2
| | | | | | | | | | | | | | | | | If bpf_map_precharge_memlock() did not fail, then we set err to zero. However, any subsequent failure from either alloc_percpu() or the bpf_map_area_alloc() will return ERR_PTR(0) which in find_and_alloc_map() will cause NULL pointer deref. In devmap we have the convention that we return -EINVAL on page count overflow, so keep the same logic here and just set err to -ENOMEM after successful bpf_map_precharge_memlock(). Fixes: fbfc504a24f5 ("bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Björn Töpel <bjorn.topel@intel.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAPBjörn Töpel2018-05-041-0/+239
The xskmap is yet another BPF map, very much inspired by dev/cpu/sockmap, and is a holder of AF_XDP sockets. A user application adds AF_XDP sockets into the map, and by using the bpf_redirect_map helper, an XDP program can redirect XDP frames to an AF_XDP socket. Note that a socket that is bound to certain ifindex/queue index will *only* accept XDP frames from that netdev/queue index. If an XDP program tries to redirect from a netdev/queue index other than what the socket is bound to, the frame will not be received on the socket. A socket can reside in multiple maps. v3: Fixed race and simplified code. v2: Removed one indirection in map lookup. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>