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* Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds2019-07-201-3/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core fixes from Thomas Gleixner: - A collection of objtool fixes which address recent fallout partially exposed by newer toolchains, clang, BPF and general code changes. - Force USER_DS for user stack traces [ Note: the "objtool fixes" are not all to objtool itself, but for kernel code that triggers objtool warnings. Things like missing function size annotations, or code that confuses the unwinder etc. - Linus] * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) objtool: Support conditional retpolines objtool: Convert insn type to enum objtool: Fix seg fault on bad switch table entry objtool: Support repeated uses of the same C jump table objtool: Refactor jump table code objtool: Refactor sibling call detection logic objtool: Do frame pointer check before dead end check objtool: Change dead_end_function() to return boolean objtool: Warn on zero-length functions objtool: Refactor function alias logic objtool: Track original function across branches objtool: Add mcsafe_handle_tail() to the uaccess safe list bpf: Disable GCC -fgcse optimization for ___bpf_prog_run() x86/uaccess: Remove redundant CLACs in getuser/putuser error paths x86/uaccess: Don't leak AC flag into fentry from mcsafe_handle_tail() x86/uaccess: Remove ELF function annotation from copy_user_handle_tail() x86/head/64: Annotate start_cpu0() as non-callable x86/entry: Fix thunk function ELF sizes x86/kvm: Don't call kvm_spurious_fault() from .fixup x86/kvm: Replace vmx_vmenter()'s call to kvm_spurious_fault() with UD2 ...
| * bpf: Disable GCC -fgcse optimization for ___bpf_prog_run()Josh Poimboeuf2019-07-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On x86-64, with CONFIG_RETPOLINE=n, GCC's "global common subexpression elimination" optimization results in ___bpf_prog_run()'s jumptable code changing from this: select_insn: jmp *jumptable(, %rax, 8) ... ALU64_ADD_X: ... jmp *jumptable(, %rax, 8) ALU_ADD_X: ... jmp *jumptable(, %rax, 8) to this: select_insn: mov jumptable, %r12 jmp *(%r12, %rax, 8) ... ALU64_ADD_X: ... jmp *(%r12, %rax, 8) ALU_ADD_X: ... jmp *(%r12, %rax, 8) The jumptable address is placed in a register once, at the beginning of the function. The function execution can then go through multiple indirect jumps which rely on that same register value. This has a few issues: 1) Objtool isn't smart enough to be able to track such a register value across multiple recursive indirect jumps through the jump table. 2) With CONFIG_RETPOLINE enabled, this optimization actually results in a small slowdown. I measured a ~4.7% slowdown in the test_bpf "tcpdump port 22" selftest. This slowdown is actually predicted by the GCC manual: Note: When compiling a program using computed gotos, a GCC extension, you may get better run-time performance if you disable the global common subexpression elimination pass by adding -fno-gcse to the command line. So just disable the optimization for this function. Fixes: e55a73251da3 ("bpf: Fix ORC unwinding in non-JIT BPF code") Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/30c3ca29ba037afcbd860a8672eef0021addf9fe.1563413318.git.jpoimboe@redhat.com
| * Merge branch 'x86/debug' into core/urgentThomas Gleixner2019-07-181-2/+1
| |\ | | | | | | | | | | | | Pick up the two pending objtool patches as the next round of objtool fixes depend on them.
| | * bpf: Fix ORC unwinding in non-JIT BPF codeJosh Poimboeuf2019-07-091-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Objtool previously ignored ___bpf_prog_run() because it didn't understand the jump table. This resulted in the ORC unwinder not being able to unwind through non-JIT BPF code. Now that objtool knows how to read jump tables, remove the whitelist and annotate the jump table so objtool can recognize it. Also add an additional "const" to the jump table definition to clarify that the text pointers are constant. Otherwise GCC sets the section writable flag and the assembler spits out warnings. Fixes: d15d356887e7 ("perf/x86: Make perf callchains work without CONFIG_FRAME_POINTER") Reported-by: Song Liu <songliubraving@fb.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kairui Song <kasong@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Daniel Borkmann <daniel@iogearbox.net> Link: https://lkml.kernel.org/r/881939122b88f32be4c374d248c09d7527a87e35.1561685471.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | bpf: fix BTF verifier size resolution logicAndrii Nakryiko2019-07-151-7/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BTF verifier has a size resolution bug which in some circumstances leads to invalid size resolution for, e.g., TYPEDEF modifier. This happens if we have [1] PTR -> [2] TYPEDEF -> [3] ARRAY, in which case due to being in pointer context ARRAY size won't be resolved (because for pointer it doesn't matter, so it's a sink in pointer context), but it will be permanently remembered as zero for TYPEDEF and TYPEDEF will be marked as RESOLVED. Eventually ARRAY size will be resolved correctly, but TYPEDEF resolved_size won't be updated anymore. This, subsequently, will lead to erroneous map creation failure, if that TYPEDEF is specified as either key or value, as key_size/value_size won't correspond to resolved size of TYPEDEF (kernel will believe it's zero). Note, that if BTF was ordered as [1] ARRAY <- [2] TYPEDEF <- [3] PTR, this won't be a problem, as by the time we get to TYPEDEF, ARRAY's size is already calculated and stored. This bug manifests itself in rejecting BTF-defined maps that use array typedef as a value type: typedef int array_t[16]; struct { __uint(type, BPF_MAP_TYPE_ARRAY); __type(value, array_t); /* i.e., array_t *value; */ } test_map SEC(".maps"); The fix consists on not relying on modifier's resolved_size and instead using modifier's resolved_id (type ID for "concrete" type to which modifier eventually resolves) and doing size determination for that resolved type. This allow to preserve existing "early DFS termination" logic for PTR or STRUCT_OR_ARRAY contexts, but still do correct size determination for modifier types. Fixes: eb3f595dab40 ("bpf: btf: Validate type reference") Cc: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
* | | bpf: verifier: avoid fall-through warningsGustavo A. R. Silva2019-07-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In preparation to enabling -Wimplicit-fallthrough, this patch silences the following warning: kernel/bpf/verifier.c: In function ‘check_return_code’: kernel/bpf/verifier.c:6106:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (env->prog->expected_attach_type == BPF_CGROUP_UDP4_RECVMSG || ^ kernel/bpf/verifier.c:6109:2: note: here case BPF_PROG_TYPE_CGROUP_SKB: ^~~~ Warning level 3 was used: -Wimplicit-fallthrough=3 Notice that is much clearer to explicitly add breaks in each case statement (that actually contains some code), rather than letting the code to fall through. This patch is part of the ongoing efforts to enable -Wimplicit-fallthrough. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
* | | bpf: fix precision bit propagation for BPF_ST instructionsAndrii Nakryiko2019-07-121-7/+4
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When backtracking instructions to propagate precision bit for registers and stack slots, one class of instructions (BPF_ST) weren't handled causing extra stack slots to be propagated into parent state. Parent state might not have that much stack allocated, though, which causes warning on invalid stack slot usage. This patch adds handling of BPF_ST instructions: BPF_MEM | <size> | BPF_ST: *(size *) (dst_reg + off) = imm32 Reported-by: syzbot+4da3ff23081bafe74fc2@syzkaller.appspotmail.com Fixes: b5dc0163d8fd ("bpf: precise scalar_value tracking") Cc: Alexei Starovoitov <ast@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2019-07-1116-413/+1887
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking updates from David Miller: "Some highlights from this development cycle: 1) Big refactoring of ipv6 route and neigh handling to support nexthop objects configurable as units from userspace. From David Ahern. 2) Convert explored_states in BPF verifier into a hash table, significantly decreased state held for programs with bpf2bpf calls, from Alexei Starovoitov. 3) Implement bpf_send_signal() helper, from Yonghong Song. 4) Various classifier enhancements to mvpp2 driver, from Maxime Chevallier. 5) Add aRFS support to hns3 driver, from Jian Shen. 6) Fix use after free in inet frags by allocating fqdirs dynamically and reworking how rhashtable dismantle occurs, from Eric Dumazet. 7) Add act_ctinfo packet classifier action, from Kevin Darbyshire-Bryant. 8) Add TFO key backup infrastructure, from Jason Baron. 9) Remove several old and unused ISDN drivers, from Arnd Bergmann. 10) Add devlink notifications for flash update status to mlxsw driver, from Jiri Pirko. 11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski. 12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes. 13) Various enhancements to ipv6 flow label handling, from Eric Dumazet and Willem de Bruijn. 14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van der Merwe, and others. 15) Various improvements to axienet driver including converting it to phylink, from Robert Hancock. 16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean. 17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana Radulescu. 18) Add devlink health reporting to mlx5, from Moshe Shemesh. 19) Convert stmmac over to phylink, from Jose Abreu. 20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from Shalom Toledo. 21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera. 22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel. 23) Track spill/fill of constants in BPF verifier, from Alexei Starovoitov. 24) Support bounded loops in BPF, from Alexei Starovoitov. 25) Various page_pool API fixes and improvements, from Jesper Dangaard Brouer. 26) Just like ipv4, support ref-countless ipv6 route handling. From Wei Wang. 27) Support VLAN offloading in aquantia driver, from Igor Russkikh. 28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy. 29) Add flower GRE encap/decap support to nfp driver, from Pieter Jansen van Vuuren. 30) Protect against stack overflow when using act_mirred, from John Hurley. 31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen. 32) Use page_pool API in netsec driver, Ilias Apalodimas. 33) Add Google gve network driver, from Catherine Sullivan. 34) More indirect call avoidance, from Paolo Abeni. 35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan. 36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek. 37) Add MPLS manipulation actions to TC, from John Hurley. 38) Add sending a packet to connection tracking from TC actions, and then allow flower classifier matching on conntrack state. From Paul Blakey. 39) Netfilter hw offload support, from Pablo Neira Ayuso" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits) net/mlx5e: Return in default case statement in tx_post_resync_params mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync(). net: dsa: add support for BRIDGE_MROUTER attribute pkt_sched: Include const.h net: netsec: remove static declaration for netsec_set_tx_de() net: netsec: remove superfluous if statement netfilter: nf_tables: add hardware offload support net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload net: flow_offload: add flow_block_cb_is_busy() and use it net: sched: remove tcf block API drivers: net: use flow block API net: sched: use flow block API net: flow_offload: add flow_block_cb_{priv, incref, decref}() net: flow_offload: add list handling functions net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free() net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_* net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND net: flow_offload: add flow_block_cb_setup_simple() net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC ...
| * Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2019-07-082-8/+8
| |\ | | | | | | | | | | | | | | | Two cases of overlapping changes, nothing fancy. Signed-off-by: David S. Miller <davem@davemloft.net>
| | * Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller2019-07-032-8/+8
| | |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Daniel Borkmann says: ==================== pull-request: bpf 2019-07-03 The following pull-request contains BPF updates for your *net* tree. The main changes are: 1) Fix the interpreter to properly handle BPF_ALU32 | BPF_ARSH on BE architectures, from Jiong. 2) Fix several bugs in the x32 BPF JIT for handling shifts by 0, from Luke and Xi. 3) Fix NULL pointer deref in btf_type_is_resolve_source_only(), from Stanislav. 4) Properly handle the check that forwarding is enabled on the device in bpf_ipv6_fib_lookup() helper code, from Anton. 5) Fix UAPI bpf_prog_info fields alignment for archs that have 16 bit alignment such as m68k, from Baruch. 6) Fix kernel hanging in unregister_netdevice loop while unregistering device bound to XDP socket, from Ilya. 7) Properly terminate tail update in xskq_produce_flush_desc(), from Nathan. 8) Fix broken always_inline handling in test_lwt_seg6local, from Jiri. 9) Fix bpftool to use correct argument in cgroup errors, from Jakub. 10) Fix detaching dummy prog in XDP redirect sample code, from Prashant. 11) Add Jonathan to AF_XDP reviewers, from Björn. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| | | * bpf: fix BPF_ALU32 | BPF_ARSH on BE archesJiong Wang2019-06-261-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Yauheni reported the following code do not work correctly on BE arches: ALU_ARSH_X: DST = (u64) (u32) ((*(s32 *) &DST) >> SRC); CONT; ALU_ARSH_K: DST = (u64) (u32) ((*(s32 *) &DST) >> IMM); CONT; and are causing failure of test_verifier test 'arsh32 on imm 2' on BE arches. The code is taking address and interpreting memory directly, so is not endianness neutral. We should instead perform standard C type casting on the variable. A u64 to s32 conversion will drop the high 32-bit and reserve the low 32-bit as signed integer, this is all we want. Fixes: 2dc6b100f928 ("bpf: interpreter support BPF_ALU | BPF_ARSH") Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| | | * bpf: fix NULL deref in btf_type_is_resolve_source_onlyStanislav Fomichev2019-06-241-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 1dc92851849c ("bpf: kernel side support for BTF Var and DataSec") added invocations of btf_type_is_resolve_source_only before btf_type_nosize_or_null which checks for the NULL pointer. Swap the order of btf_type_nosize_or_null and btf_type_is_resolve_source_only to make sure the do the NULL pointer check first. Fixes: 1dc92851849c ("bpf: kernel side support for BTF Var and DataSec") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | bpf: cgroup: Fix build error without CONFIG_NETYueHaibing2019-07-081-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If CONFIG_NET is not set and CONFIG_CGROUP_BPF=y, gcc building fails: kernel/bpf/cgroup.o: In function `cg_sockopt_func_proto': cgroup.c:(.text+0x237e): undefined reference to `bpf_sk_storage_get_proto' cgroup.c:(.text+0x2394): undefined reference to `bpf_sk_storage_delete_proto' kernel/bpf/cgroup.o: In function `__cgroup_bpf_run_filter_getsockopt': (.text+0x2a1f): undefined reference to `lock_sock_nested' (.text+0x2ca2): undefined reference to `release_sock' kernel/bpf/cgroup.o: In function `__cgroup_bpf_run_filter_setsockopt': (.text+0x3006): undefined reference to `lock_sock_nested' (.text+0x32bb): undefined reference to `release_sock' Reported-by: Hulk Robot <hulkci@huawei.com> Suggested-by: Stanislav Fomichev <sdf@fomichev.me> Fixes: 0d01da6afc54 ("bpf: implement getsockopt and setsockopt hooks") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | bpf: fix precision trackingAlexei Starovoitov2019-07-031-14/+107
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When equivalent state is found the current state needs to propagate precision marks. Otherwise the verifier will prune the search incorrectly. There is a price for correctness: before before broken fixed cnst spill precise precise bpf_lb-DLB_L3.o 1923 8128 1863 1898 bpf_lb-DLB_L4.o 3077 6707 2468 2666 bpf_lb-DUNKNOWN.o 1062 1062 544 544 bpf_lxc-DDROP_ALL.o 166729 380712 22629 36823 bpf_lxc-DUNKNOWN.o 174607 440652 28805 45325 bpf_netdev.o 8407 31904 6801 7002 bpf_overlay.o 5420 23569 4754 4858 bpf_lxc_jit.o 39389 359445 50925 69631 Overall precision tracking is still very effective. Fixes: b5dc0163d8fd ("bpf: precise scalar_value tracking") Reported-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Tested-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | devmap: Allow map lookups from eBPFToke Høiland-Jørgensen2019-06-292-5/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We don't currently allow lookups into a devmap from eBPF, because the map lookup returns a pointer directly to the dev->ifindex, which shouldn't be modifiable from eBPF. However, being able to do lookups in devmaps is useful to know (e.g.) whether forwarding to a specific interface is enabled. Currently, programs work around this by keeping a shadow map of another type which indicates whether a map index is valid. Since we now have a flag to make maps read-only from the eBPF side, we can simply lift the lookup restriction if we make sure this flag is always set. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | devmap/cpumap: Use flush list instead of bitmapToke Høiland-Jørgensen2019-06-292-117/+95
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The socket map uses a linked list instead of a bitmap to keep track of which entries to flush. Do the same for devmap and cpumap, as this means we don't have to care about the map index when enqueueing things into the map (and so we can cache the map lookup). Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | xskmap: Move non-standard list manipulation to helperToke Høiland-Jørgensen2019-06-291-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a helper in list.h for the non-standard way of clearing a list that is used in xskmap. This makes it easier to reuse it in the other map types, and also makes sure this usage is not forgotten in any list refactorings in the future. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | bpf: implement getsockopt and setsockopt hooksStanislav Fomichev2019-06-274-0/+369
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement new BPF_PROG_TYPE_CGROUP_SOCKOPT program type and BPF_CGROUP_{G,S}ETSOCKOPT cgroup hooks. BPF_CGROUP_SETSOCKOPT can modify user setsockopt arguments before passing them down to the kernel or bypass kernel completely. BPF_CGROUP_GETSOCKOPT can can inspect/modify getsockopt arguments that kernel returns. Both hooks reuse existing PTR_TO_PACKET{,_END} infrastructure. The buffer memory is pre-allocated (because I don't think there is a precedent for working with __user memory from bpf). This might be slow to do for each {s,g}etsockopt call, that's why I've added __cgroup_bpf_prog_array_is_empty that exits early if there is nothing attached to a cgroup. Note, however, that there is a race between __cgroup_bpf_prog_array_is_empty and BPF_PROG_RUN_ARRAY where cgroup program layout might have changed; this should not be a problem because in general there is a race between multiple calls to {s,g}etsocktop and user adding/removing bpf progs from a cgroup. The return code of the BPF program is handled as follows: * 0: EPERM * 1: success, continue with next BPF program in the cgroup chain v9: * allow overwriting setsockopt arguments (Alexei Starovoitov): * use set_fs (same as kernel_setsockopt) * buffer is always kzalloc'd (no small on-stack buffer) v8: * use s32 for optlen (Andrii Nakryiko) v7: * return only 0 or 1 (Alexei Starovoitov) * always run all progs (Alexei Starovoitov) * use optval=0 as kernel bypass in setsockopt (Alexei Starovoitov) (decided to use optval=-1 instead, optval=0 might be a valid input) * call getsockopt hook after kernel handlers (Alexei Starovoitov) v6: * rework cgroup chaining; stop as soon as bpf program returns 0 or 2; see patch with the documentation for the details * drop Andrii's and Martin's Acked-by (not sure they are comfortable with the new state of things) v5: * skip copy_to_user() and put_user() when ret == 0 (Martin Lau) v4: * don't export bpf_sk_fullsock helper (Martin Lau) * size != sizeof(__u64) for uapi pointers (Martin Lau) * offsetof instead of bpf_ctx_range when checking ctx access (Martin Lau) v3: * typos in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY comments (Andrii Nakryiko) * reverse christmas tree in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY (Andrii Nakryiko) * use __bpf_md_ptr instead of __u32 for optval{,_end} (Martin Lau) * use BPF_FIELD_SIZEOF() for consistency (Martin Lau) * new CG_SOCKOPT_ACCESS macro to wrap repeated parts v2: * moved bpf_sockopt_kern fields around to remove a hole (Martin Lau) * aligned bpf_sockopt_kern->buf to 8 bytes (Martin Lau) * bpf_prog_array_is_empty instead of bpf_prog_array_length (Martin Lau) * added [0,2] return code check to verifier (Martin Lau) * dropped unused buf[64] from the stack (Martin Lau) * use PTR_TO_SOCKET for bpf_sockopt->sk (Martin Lau) * dropped bpf_target_off from ctx rewrites (Martin Lau) * use return code for kernel bypass (Martin Lau & Andrii Nakryiko) Cc: Andrii Nakryiko <andriin@fb.com> Cc: Martin Lau <kafai@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | bpf: fix cgroup bpf release synchronizationRoman Gushchin2019-06-271-1/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 4bfc0bb2c60e ("bpf: decouple the lifetime of cgroup_bpf from cgroup itself"), cgroup_bpf release occurs asynchronously (from a worker context), and before the release of the cgroup itself. This introduced a previously non-existing race between the release and update paths. E.g. if a leaf's cgroup_bpf is released and a new bpf program is attached to the one of ancestor cgroups at the same time. The race may result in double-free and other memory corruptions. To fix the problem, let's protect the body of cgroup_bpf_release() with cgroup_mutex, as it was effectively previously, when all this code was called from the cgroup release path with cgroup mutex held. Also let's skip cgroups, which have no chances to invoke a bpf program, on the update path. If the cgroup bpf refcnt reached 0, it means that the cgroup is offline (no attached processes), and there are no associated sockets left. It means there is no point in updating effective progs array! And it can lead to a leak, if it happens after the release. So, let's skip such cgroups. Big thanks for Tejun Heo for discovering and debugging of this problem! Fixes: 4bfc0bb2c60e ("bpf: decouple the lifetime of cgroup_bpf from cgroup itself") Reported-by: Tejun Heo <tj@kernel.org> Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | xdp: Add tracepoint for bulk XDP_TXToshiaki Makita2019-06-251-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is introduced for admins to check what is happening on XDP_TX when bulk XDP_TX is in use, which will be first introduced in veth in next commit. v3: - Add act field to be in line with other XDP tracepoints. Signed-off-by: Toshiaki Makita <toshiaki.makita1@gmail.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2019-06-223-12/+3
| |\| | | | | | | | | | | | | | | | | | | | | | Minor SPDX change conflict. Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller2019-06-204-71/+734
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Alexei Starovoitov says: ==================== pull-request: bpf-next 2019-06-19 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) new SO_REUSEPORT_DETACH_BPF setsocktopt, from Martin. 2) BTF based map definition, from Andrii. 3) support bpf_map_lookup_elem for xskmap, from Jonathan. 4) bounded loops and scalar precision logic in the verifier, from Alexei. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| | * | | bpf: precise scalar_value trackingAlexei Starovoitov2019-06-191-11/+480
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce precision tracking logic that helps cilium programs the most: old clang old clang new clang new clang with all patches with all patches bpf_lb-DLB_L3.o 1838 2283 1923 1863 bpf_lb-DLB_L4.o 3218 2657 3077 2468 bpf_lb-DUNKNOWN.o 1064 545 1062 544 bpf_lxc-DDROP_ALL.o 26935 23045 166729 22629 bpf_lxc-DUNKNOWN.o 34439 35240 174607 28805 bpf_netdev.o 9721 8753 8407 6801 bpf_overlay.o 6184 7901 5420 4754 bpf_lxc_jit.o 39389 50925 39389 50925 Consider code: 654: (85) call bpf_get_hash_recalc#34 655: (bf) r7 = r0 656: (15) if r8 == 0x0 goto pc+29 657: (bf) r2 = r10 658: (07) r2 += -48 659: (18) r1 = 0xffff8881e41e1b00 661: (85) call bpf_map_lookup_elem#1 662: (15) if r0 == 0x0 goto pc+23 663: (69) r1 = *(u16 *)(r0 +0) 664: (15) if r1 == 0x0 goto pc+21 665: (bf) r8 = r7 666: (57) r8 &= 65535 667: (bf) r2 = r8 668: (3f) r2 /= r1 669: (2f) r2 *= r1 670: (bf) r1 = r8 671: (1f) r1 -= r2 672: (57) r1 &= 255 673: (25) if r1 > 0x1e goto pc+12 R0=map_value(id=0,off=0,ks=20,vs=64,imm=0) R1_w=inv(id=0,umax_value=30,var_off=(0x0; 0x1f)) 674: (67) r1 <<= 1 675: (0f) r0 += r1 At this point the verifier will notice that scalar R1 is used in map pointer adjustment. R1 has to be precise for later operations on R0 to be validated properly. The verifier will backtrack the above code in the following way: last_idx 675 first_idx 664 regs=2 stack=0 before 675: (0f) r0 += r1 // started backtracking R1 regs=2 is a bitmask regs=2 stack=0 before 674: (67) r1 <<= 1 regs=2 stack=0 before 673: (25) if r1 > 0x1e goto pc+12 regs=2 stack=0 before 672: (57) r1 &= 255 regs=2 stack=0 before 671: (1f) r1 -= r2 // now both R1 and R2 has to be precise -> regs=6 mask regs=6 stack=0 before 670: (bf) r1 = r8 // after this insn R8 and R2 has to be precise regs=104 stack=0 before 669: (2f) r2 *= r1 // after this one R8, R2, and R1 regs=106 stack=0 before 668: (3f) r2 /= r1 regs=106 stack=0 before 667: (bf) r2 = r8 regs=102 stack=0 before 666: (57) r8 &= 65535 regs=102 stack=0 before 665: (bf) r8 = r7 regs=82 stack=0 before 664: (15) if r1 == 0x0 goto pc+21 // this is the end of verifier state. The following regs will be marked precised: R1_rw=invP(id=0,umax_value=65535,var_off=(0x0; 0xffff)) R7_rw=invP(id=0) parent didn't have regs=82 stack=0 marks // so backtracking continues into parent state last_idx 663 first_idx 655 regs=82 stack=0 before 663: (69) r1 = *(u16 *)(r0 +0) // R1 was assigned no need to track it further regs=80 stack=0 before 662: (15) if r0 == 0x0 goto pc+23 // keep tracking R7 regs=80 stack=0 before 661: (85) call bpf_map_lookup_elem#1 // keep tracking R7 regs=80 stack=0 before 659: (18) r1 = 0xffff8881e41e1b00 regs=80 stack=0 before 658: (07) r2 += -48 regs=80 stack=0 before 657: (bf) r2 = r10 regs=80 stack=0 before 656: (15) if r8 == 0x0 goto pc+29 regs=80 stack=0 before 655: (bf) r7 = r0 // here the assignment into R7 // mark R0 to be precise: R0_rw=invP(id=0) parent didn't have regs=1 stack=0 marks // regs=1 -> tracking R0 last_idx 654 first_idx 644 regs=1 stack=0 before 654: (85) call bpf_get_hash_recalc#34 // and in the parent frame it was a return value // nothing further to backtrack Two scalar registers not marked precise are equivalent from state pruning point of view. More details in the patch comments. It doesn't support bpf2bpf calls yet and enabled for root only. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| | * | | bpf: fix callees pruning callersAlexei Starovoitov2019-06-191-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The commit 7640ead93924 partially resolved the issue of callees incorrectly pruning the callers. With introduction of bounded loops and jmps_processed heuristic single verifier state may contain multiple branches and calls. It's possible that new verifier state (for future pruning) will be allocated inside callee. Then callee will exit (still within the same verifier state). It will go back to the caller and there R6-R9 registers will be read and will trigger mark_reg_read. But the reg->live for all frames but the top frame is not set to LIVE_NONE. Hence mark_reg_read will fail to propagate liveness into parent and future walking will incorrectly conclude that the states are equivalent because LIVE_READ is not set. In other words the rule for parent/live should be: whenever register parentage chain is set the reg->live should be set to LIVE_NONE. is_state_visited logic already follows this rule for spilled registers. Fixes: 7640ead93924 ("bpf: verifier: make sure callees don't prune with caller differences") Fixes: f4d7e40a5b71 ("bpf: introduce function calls (verification)") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| | * | | bpf: introduce bounded loopsAlexei Starovoitov2019-06-191-12/+131
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow the verifier to validate the loops by simulating their execution. Exisiting programs have used '#pragma unroll' to unroll the loops by the compiler. Instead let the verifier simulate all iterations of the loop. In order to do that introduce parentage chain of bpf_verifier_state and 'branches' counter for the number of branches left to explore. See more detailed algorithm description in bpf_verifier.h This algorithm borrows the key idea from Edward Cree approach: https://patchwork.ozlabs.org/patch/877222/ Additional state pruning heuristics make such brute force loop walk practical even for large loops. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| | * | | bpf: extend is_branch_taken to registersAlexei Starovoitov2019-06-191-15/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch extends is_branch_taken() logic from JMP+K instructions to JMP+X instructions. Conditional branches are often done when src and dst registers contain known scalars. In such case the verifier can follow the branch that is going to be taken when program executes. That speeds up the verification and is essential feature to support bounded loops. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| | * | | bpf: track spill/fill of constantsAlexei Starovoitov2019-06-191-25/+65
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Compilers often spill induction variables into the stack, hence it is necessary for the verifier to track scalar values of the registers through stack slots. Also few bpf programs were incorrectly rejected in the past, since the verifier was not able to track such constants while they were used to compute offsets into packet headers. Tracking constants through the stack significantly decreases the chances of state pruning, since two different constants are considered to be different by state equivalency. End result that cilium tests suffer serious degradation in the number of states processed and corresponding verification time increase. before after bpf_lb-DLB_L3.o 1838 6441 bpf_lb-DLB_L4.o 3218 5908 bpf_lb-DUNKNOWN.o 1064 1064 bpf_lxc-DDROP_ALL.o 26935 93790 bpf_lxc-DUNKNOWN.o 34439 123886 bpf_netdev.o 9721 31413 bpf_overlay.o 6184 18561 bpf_lxc_jit.o 39389 359445 After further debugging turned out that cillium progs are getting hurt by clang due to the same constant tracking issue. Newer clang generates better code by spilling less to the stack. Instead it keeps more constants in the registers which hurts state pruning since the verifier already tracks constants in the registers: old clang new clang (no spill/fill tracking introduced by this patch) bpf_lb-DLB_L3.o 1838 1923 bpf_lb-DLB_L4.o 3218 3077 bpf_lb-DUNKNOWN.o 1064 1062 bpf_lxc-DDROP_ALL.o 26935 166729 bpf_lxc-DUNKNOWN.o 34439 174607 bpf_netdev.o 9721 8407 bpf_overlay.o 6184 5420 bpf_lcx_jit.o 39389 39389 The final table is depressing: old clang old clang new clang new clang const spill/fill const spill/fill bpf_lb-DLB_L3.o 1838 6441 1923 8128 bpf_lb-DLB_L4.o 3218 5908 3077 6707 bpf_lb-DUNKNOWN.o 1064 1064 1062 1062 bpf_lxc-DDROP_ALL.o 26935 93790 166729 380712 bpf_lxc-DUNKNOWN.o 34439 123886 174607 440652 bpf_netdev.o 9721 31413 8407 31904 bpf_overlay.o 6184 18561 5420 23569 bpf_lxc_jit.o 39389 359445 39389 359445 Tracking constants in the registers hurts state pruning already. Adding tracking of constants through stack hurts pruning even more. The later patch address this general constant tracking issue with coarse/precise logic. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| | * | | bpf: silence warning messages in coreValdis Klētnieks2019-06-121-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Compiling kernel/bpf/core.c with W=1 causes a flood of warnings: kernel/bpf/core.c:1198:65: warning: initialized field overwritten [-Woverride-init] 1198 | #define BPF_INSN_3_TBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = true | ^~~~ kernel/bpf/core.c:1087:2: note: in expansion of macro 'BPF_INSN_3_TBL' 1087 | INSN_3(ALU, ADD, X), \ | ^~~~~~ kernel/bpf/core.c:1202:3: note: in expansion of macro 'BPF_INSN_MAP' 1202 | BPF_INSN_MAP(BPF_INSN_2_TBL, BPF_INSN_3_TBL), | ^~~~~~~~~~~~ kernel/bpf/core.c:1198:65: note: (near initialization for 'public_insntable[12]') 1198 | #define BPF_INSN_3_TBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = true | ^~~~ kernel/bpf/core.c:1087:2: note: in expansion of macro 'BPF_INSN_3_TBL' 1087 | INSN_3(ALU, ADD, X), \ | ^~~~~~ kernel/bpf/core.c:1202:3: note: in expansion of macro 'BPF_INSN_MAP' 1202 | BPF_INSN_MAP(BPF_INSN_2_TBL, BPF_INSN_3_TBL), | ^~~~~~~~~~~~ 98 copies of the above. The attached patch silences the warnings, because we *know* we're overwriting the default initializer. That leaves bpf/core.c with only 6 other warnings, which become more visible in comparison. Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| | * | | bpf: Allow bpf_map_lookup_elem() on an xskmapJonathan Lemon2019-06-102-2/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the AF_XDP code uses a separate map in order to determine if an xsk is bound to a queue. Instead of doing this, have bpf_map_lookup_elem() return a xdp_sock. Rearrange some xdp_sock members to eliminate structure holes. Remove selftest - will be added back in later patch. Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| | * | | bpf: remove redundant assignment to errColin Ian King2019-06-042-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The variable err is assigned with the value -EINVAL that is never read and it is re-assigned a new value later on. The assignment is redundant and can be removed. Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | | xdp: page_pool related fix to cpumapJesper Dangaard Brouer2019-06-191-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When converting an xdp_frame into an SKB, and sending this into the network stack, then the underlying XDP memory model need to release associated resources, because the network stack don't have callbacks for XDP memory models. The only memory model that needs this is page_pool, when a driver use the DMA-mapping feature. Introduce page_pool_release_page(), which basically does the same as page_pool_unmap_page(). Add xdp_release_frame() as the XDP memory model interface for calling it, if the memory model match MEM_TYPE_PAGE_POOL, to save the function call overhead for others. Have cpumap call xdp_release_frame() before xdp_scrub_frame(). Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2019-06-1711-80/+36
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Honestly all the conflicts were simple overlapping changes, nothing really interesting to report. Signed-off-by: David S. Miller <davem@davemloft.net>
| * \ \ \ \ Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2019-06-078-33/+8
| |\ \ \ \ \ | | |_|/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | Some ISDN files that got removed in net-next had some changes done in mainline, take the removals. Signed-off-by: David S. Miller <davem@davemloft.net>
| * | | | | bpf: move memory size checks to bpf_map_charge_init()Roman Gushchin2019-05-3111-56/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Most bpf map types doing similar checks and bytes to pages conversion during memory allocation and charging. Let's unify these checks by moving them into bpf_map_charge_init(). Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: rework memlock-based memory accounting for mapsRoman Gushchin2019-05-3111-82/+100
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to unify the existing memlock charging code with the memcg-based memory accounting, which will be added later, let's rework the current scheme. Currently the following design is used: 1) .alloc() callback optionally checks if the allocation will likely succeed using bpf_map_precharge_memlock() 2) .alloc() performs actual allocations 3) .alloc() callback calculates map cost and sets map.memory.pages 4) map_create() calls bpf_map_init_memlock() which sets map.memory.user and performs actual charging; in case of failure the map is destroyed <map is in use> 1) bpf_map_free_deferred() calls bpf_map_release_memlock(), which performs uncharge and releases the user 2) .map_free() callback releases the memory The scheme can be simplified and made more robust: 1) .alloc() calculates map cost and calls bpf_map_charge_init() 2) bpf_map_charge_init() sets map.memory.user and performs actual charge 3) .alloc() performs actual allocations <map is in use> 1) .map_free() callback releases the memory 2) bpf_map_charge_finish() performs uncharge and releases the user The new scheme also allows to reuse bpf_map_charge_init()/finish() functions for memcg-based accounting. Because charges are performed before actual allocations and uncharges after freeing the memory, no bogus memory pressure can be created. In cases when the map structure is not available (e.g. it's not created yet, or is already destroyed), on-stack bpf_map_memory structure is used. The charge can be transferred with the bpf_map_charge_move() function. Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: group memory related fields in struct bpf_map_memoryRoman Gushchin2019-05-3111-25/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Group "user" and "pages" fields of bpf_map into the bpf_map_memory structure. Later it can be extended with "memcg" and other related information. The main reason for a such change (beside cosmetics) is to pass bpf_map_memory structure to charging functions before the actual allocation of bpf_map. Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: add memlock precharge check for cgroup_local_storageRoman Gushchin2019-05-311-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Cgroup local storage maps lack the memlock precharge check, which is performed before the memory allocation for most other bpf map types. Let's add it in order to unify all map types. Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: Update __cgroup_bpf_run_filter_skb with cnbrakmo2019-05-311-5/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For egress packets, __cgroup_bpf_fun_filter_skb() will now call BPF_PROG_CGROUP_INET_EGRESS_RUN_ARRAY() instead of PROG_CGROUP_RUN_ARRAY() in order to propagate congestion notifications (cn) requests to TCP callers. For egress packets, this function can return: NET_XMIT_SUCCESS (0) - continue with packet output NET_XMIT_DROP (1) - drop packet and notify TCP to call cwr NET_XMIT_CN (2) - continue with packet output and notify TCP to call cwr -EPERM - drop packet For ingress packets, this function will return -EPERM if any attached program was found and if it returned != 1 during execution. Otherwise 0 is returned. Signed-off-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: cgroup inet skb programs can return 0 to 3brakmo2019-05-312-3/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allows cgroup inet skb programs to return values in the range [0, 3]. The second bit is used to deterine if congestion occurred and higher level protocol should decrease rate. E.g. TCP would call tcp_enter_cwr() The bpf_prog must set expected_attach_type to BPF_CGROUP_INET_EGRESS at load time if it uses the new return values (i.e. 2 or 3). The expected_attach_type is currently not enforced for BPF_PROG_TYPE_CGROUP_SKB. e.g Meaning the current bpf_prog with expected_attach_type setting to BPF_CGROUP_INET_EGRESS can attach to BPF_CGROUP_INET_INGRESS. Blindly enforcing expected_attach_type will break backward compatibility. This patch adds a enforce_expected_attach_type bit to only enforce the expected_attach_type when it uses the new return value. Signed-off-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: cgroup: properly use bpf_prog_array apiStanislav Fomichev2019-05-291-11/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we don't have __rcu markers on the bpf_prog_array helpers, let's use proper rcu_dereference_protected to obtain array pointer under mutex. We also don't need __rcu annotations on cgroup_bpf.inactive since it's not read/updated concurrently. v4: * drop cgroup_rcu_xyz wrappers and use rcu APIs directly; presumably should be more clear to understand which mutex/refcount protects each particular place v3: * amend cgroup_rcu_dereference to include percpu_ref_is_dying; cgroup_bpf is now reference counted and we don't hold cgroup_mutex anymore in cgroup_bpf_release v2: * replace xchg with rcu_swap_protected Cc: Roman Gushchin <guro@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Acked-by: Roman Gushchin <guro@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | | | bpf: remove __rcu annotations from bpf_prog_arrayStanislav Fomichev2019-05-291-24/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Drop __rcu annotations and rcu read sections from bpf_prog_array helper functions. They are not needed since all existing callers call those helpers from the rcu update side while holding a mutex. This guarantees that use-after-free could not happen. In the next patches I'll fix the callers with missing rcu_dereference_protected to make sparse/lockdep happy, the proper way to use these helpers is: struct bpf_prog_array __rcu *progs = ...; struct bpf_prog_array *p; mutex_lock(&mtx); p = rcu_dereference_protected(progs, lockdep_is_held(&mtx)); bpf_prog_array_length(p); bpf_prog_array_copy_to_user(p, ...); bpf_prog_array_delete_safe(p, ...); bpf_prog_array_copy_info(p, ...); bpf_prog_array_copy(p, ...); bpf_prog_array_free(p); mutex_unlock(&mtx); No functional changes! rcu_dereference_protected with lockdep_is_held should catch any cases where we update prog array without a mutex (I've looked at existing call sites and I think we hold a mutex everywhere). Motivation is to fix sparse warnings: kernel/bpf/core.c:1803:9: warning: incorrect type in argument 1 (different address spaces) kernel/bpf/core.c:1803:9: expected struct callback_head *head kernel/bpf/core.c:1803:9: got struct callback_head [noderef] <asn:4> * kernel/bpf/core.c:1877:44: warning: incorrect type in initializer (different address spaces) kernel/bpf/core.c:1877:44: expected struct bpf_prog_array_item *item kernel/bpf/core.c:1877:44: got struct bpf_prog_array_item [noderef] <asn:4> * kernel/bpf/core.c:1901:26: warning: incorrect type in assignment (different address spaces) kernel/bpf/core.c:1901:26: expected struct bpf_prog_array_item *existing kernel/bpf/core.c:1901:26: got struct bpf_prog_array_item [noderef] <asn:4> * kernel/bpf/core.c:1935:26: warning: incorrect type in assignment (different address spaces) kernel/bpf/core.c:1935:26: expected struct bpf_prog_array_item *[assigned] existing kernel/bpf/core.c:1935:26: got struct bpf_prog_array_item [noderef] <asn:4> * v2: * remove comment about potential race; that can't happen because all callers are in rcu-update section Cc: Roman Gushchin <guro@fb.com> Acked-by: Roman Gushchin <guro@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | | | bpf: decouple the lifetime of cgroup_bpf from cgroup itselfRoman Gushchin2019-05-281-4/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the lifetime of bpf programs attached to a cgroup is bound to the lifetime of the cgroup itself. It means that if a user forgets (or intentionally avoids) to detach a bpf program before removing the cgroup, it will stay attached up to the release of the cgroup. Since the cgroup can stay in the dying state (the state between being rmdir()'ed and being released) for a very long time, it leads to a waste of memory. Also, it blocks a possibility to implement the memcg-based memory accounting for bpf objects, because a circular reference dependency will occur. Charged memory pages are pinning the corresponding memory cgroup, and if the memory cgroup is pinning the attached bpf program, nothing will be ever released. A dying cgroup can not contain any processes, so the only chance for an attached bpf program to be executed is a live socket associated with the cgroup. So in order to release all bpf data early, let's count associated sockets using a new percpu refcounter. On cgroup removal the counter is transitioned to the atomic mode, and as soon as it reaches 0, all bpf programs are detached. Because cgroup_bpf_release() can block, it can't be called from the percpu ref counter callback directly, so instead an asynchronous work is scheduled. The reference counter is not socket specific, and can be used for any other types of programs, which can be executed from a cgroup-bpf hook outside of the process context, had such a need arise in the future. Signed-off-by: Roman Gushchin <guro@fb.com> Cc: jolsa@redhat.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: verifier: randomize high 32-bit when BPF_F_TEST_RND_HI32 is setJiong Wang2019-05-241-11/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch randomizes high 32-bit of a definition when BPF_F_TEST_RND_HI32 is set. Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: introduce new bpf prog load flags "BPF_F_TEST_RND_HI32"Jiong Wang2019-05-241-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | x86_64 and AArch64 perhaps are two arches that running bpf testsuite frequently, however the zero extension insertion pass is not enabled for them because of their hardware support. It is critical to guarantee the pass correction as it is supposed to be enabled at default for a couple of other arches, for example PowerPC, SPARC, arm, NFP etc. Therefore, it would be very useful if there is a way to test this pass on for example x86_64. The test methodology employed by this set is "poisoning" useless bits. High 32-bit of a definition is randomized if it is identified as not used by any later insn. Such randomization is only enabled under testing mode which is gated by the new bpf prog load flags "BPF_F_TEST_RND_HI32". Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: verifier: insert zero extension according to analysis resultJiong Wang2019-05-242-0/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After previous patches, verifier will mark a insn if it really needs zero extension on dst_reg. It is then for back-ends to decide how to use such information to eliminate unnecessary zero extension code-gen during JIT compilation. One approach is verifier insert explicit zero extension for those insns that need zero extension in a generic way, JIT back-ends then do not generate zero extension for sub-register write at default. However, only those back-ends which do not have hardware zero extension want this optimization. Back-ends like x86_64 and AArch64 have hardware zero extension support that the insertion should be disabled. This patch introduces new target hook "bpf_jit_needs_zext" which returns false at default, meaning verifier zero extension insertion is disabled at default. A back-end could override this hook to return true if it doesn't have hardware support and want verifier insert zero extension explicitly. Offload targets do not use this native target hook, instead, they could get the optimization results using bpf_prog_offload_ops.finalize. NOTE: arches could have diversified features, it is possible for one arch to have hardware zero extension support for some sub-register write insns but not for all. For example, PowerPC, SPARC have zero extended loads, but not for alu32. So when verifier zero extension insertion enabled, these JIT back-ends need to peephole insns to remove those zero extension inserted for insn that actually has hardware zero extension support. The peephole could be as simple as looking the next insn, if it is a special zero extension insn then it is safe to eliminate it if the current insn has hardware zero extension support. Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: verifier: mark patched-insn with sub-register zext flagJiong Wang2019-05-241-4/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patched insns do not go through generic verification, therefore doesn't has zero extension information collected during insn walking. We don't bother analyze them at the moment, for any sub-register def comes from them, just conservatively mark it as needing zero extension. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: verifier: mark verified-insn with sub-register zext flagJiong Wang2019-05-241-13/+160
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | eBPF ISA specification requires high 32-bit cleared when low 32-bit sub-register is written. This applies to destination register of ALU32 etc. JIT back-ends must guarantee this semantic when doing code-gen. x86_64 and AArch64 ISA has the same semantics, so the corresponding JIT back-end doesn't need to do extra work. However, 32-bit arches (arm, x86, nfp etc.) and some other 64-bit arches (PowerPC, SPARC etc) need to do explicit zero extension to meet this requirement, otherwise code like the following will fail. u64_value = (u64) u32_value ... other uses of u64_value This is because compiler could exploit the semantic described above and save those zero extensions for extending u32_value to u64_value, these JIT back-ends are expected to guarantee this through inserting extra zero extensions which however could be a significant increase on the code size. Some benchmarks show there could be ~40% sub-register writes out of total insns, meaning at least ~40% extra code-gen. One observation is these extra zero extensions are not always necessary. Take above code snippet for example, it is possible u32_value will never be casted into a u64, the value of high 32-bit of u32_value then could be ignored and extra zero extension could be eliminated. This patch implements this idea, insns defining sub-registers will be marked when the high 32-bit of the defined sub-register matters. For those unmarked insns, it is safe to eliminate high 32-bit clearnace for them. Algo: - Split read flags into READ32 and READ64. - Record index of insn that does sub-register write. Keep the index inside reg state and update it during verifier insn walking. - A full register read on a sub-register marks its definition insn as needing zero extension on dst register. A new sub-register write overrides the old one. - When propagating read64 during path pruning, also mark any insn defining a sub-register that is read in the pruned path as full-register. Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * | | | | bpf: convert explored_states to hash tableAlexei Starovoitov2019-05-241-5/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All prune points inside a callee bpf function most likely will have different callsites. For example, if function foo() is called from two callsites the half of explored states in all prune points in foo() will be useless for subsequent walking of one of those callsites. Fortunately explored_states pruning heuristics keeps the number of states per prune point small, but walking these states is still a waste of cpu time when the callsite of the current state is different from the callsite of the explored state. To improve pruning logic convert explored_states into hash table and use simple insn_idx ^ callsite hash to select hash bucket. This optimization has no effect on programs without bpf2bpf calls and drastically improves programs with calls. In the later case it reduces total memory consumption in 1M scale tests by almost 3 times (peak_states drops from 5752 to 2016). Care should be taken when comparing the states for equivalency. Since the same hash bucket can now contain states with different indices the insn_idx has to be part of verifier_state and compared. Different hash table sizes and different hash functions were explored, but the results were not significantly better vs this patch. They can be improved in the future. Hit/miss heuristic is not counting index miscompare as a miss. Otherwise verifier stats become unstable when experimenting with different hash functions. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | | | bpf: split explored_statesAlexei Starovoitov2019-05-241-18/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | split explored_states into prune_point boolean mark and link list of explored states. This removes STATE_LIST_MARK hack and allows marks to be separate from states. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * | | | | bpf: cleanup explored_statesAlexei Starovoitov2019-05-241-9/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | clean up explored_states to prep for introduction of hashtable No functional changes. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>