aboutsummaryrefslogtreecommitdiffstats
path: root/kernel/bpf (follow)
AgeCommit message (Collapse)AuthorFilesLines
2021-11-11Merge tag 'net-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds2-35/+27
Pull networking fixes from Jakub Kicinski: "Including fixes from bpf, can and netfilter. Current release - regressions: - bpf: do not reject when the stack read size is different from the tracked scalar size - net: fix premature exit from NAPI state polling in napi_disable() - riscv, bpf: fix RV32 broken build, and silence RV64 warning Current release - new code bugs: - net: fix possible NULL deref in sock_reserve_memory - amt: fix error return code in amt_init(); fix stopping the workqueue - ax88796c: use the correct ioctl callback Previous releases - always broken: - bpf: stop caching subprog index in the bpf_pseudo_func insn - security: fixups for the security hooks in sctp - nfc: add necessary privilege flags in netlink layer, limit operations to admin only - vsock: prevent unnecessary refcnt inc for non-blocking connect - net/smc: fix sk_refcnt underflow on link down and fallback - nfnetlink_queue: fix OOB when mac header was cleared - can: j1939: ignore invalid messages per standard - bpf, sockmap: - fix race in ingress receive verdict with redirect to self - fix incorrect sk_skb data_end access when src_reg = dst_reg - strparser, and tls are reusing qdisc_skb_cb and colliding - ethtool: fix ethtool msg len calculation for pause stats - vlan: fix a UAF in vlan_dev_real_dev() when ref-holder tries to access an unregistering real_dev - udp6: make encap_rcv() bump the v6 not v4 stats - drv: prestera: add explicit padding to fix m68k build - drv: felix: fix broken VLAN-tagged PTP under VLAN-aware bridge - drv: mvpp2: fix wrong SerDes reconfiguration order Misc & small latecomers: - ipvs: auto-load ipvs on genl access - mctp: sanity check the struct sockaddr_mctp padding fields - libfs: support RENAME_EXCHANGE in simple_rename() - avoid double accounting for pure zerocopy skbs" * tag 'net-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (123 commits) selftests/net: udpgso_bench_rx: fix port argument net: wwan: iosm: fix compilation warning cxgb4: fix eeprom len when diagnostics not implemented net: fix premature exit from NAPI state polling in napi_disable() net/smc: fix sk_refcnt underflow on linkdown and fallback net/mlx5: Lag, fix a potential Oops with mlx5_lag_create_definer() gve: fix unmatched u64_stats_update_end() net: ethernet: lantiq_etop: Fix compilation error selftests: forwarding: Fix packet matching in mirroring selftests vsock: prevent unnecessary refcnt inc for nonblocking connect net: marvell: mvpp2: Fix wrong SerDes reconfiguration order net: ethernet: ti: cpsw_ale: Fix access to un-initialized memory net: stmmac: allow a tc-taprio base-time of zero selftests: net: test_vxlan_under_vrf: fix HV connectivity test net: hns3: allow configure ETS bandwidth of all TCs net: hns3: remove check VF uc mac exist when set by PF net: hns3: fix some mac statistics is always 0 in device version V2 net: hns3: fix kernel crash when unload VF while it is being reset net: hns3: sync rx ring head in echo common pull net: hns3: fix pfc packet number incorrect after querying pfc parameters ...
2021-11-06bpf: Stop caching subprog index in the bpf_pseudo_func insnMartin KaFai Lau2-23/+21
This patch is to fix an out-of-bound access issue when jit-ing the bpf_pseudo_func insn (i.e. ld_imm64 with src_reg == BPF_PSEUDO_FUNC) In jit_subprog(), it currently reuses the subprog index cached in insn[1].imm. This subprog index is an index into a few array related to subprogs. For example, in jit_subprog(), it is an index to the newly allocated 'struct bpf_prog **func' array. The subprog index was cached in insn[1].imm after add_subprog(). However, this could become outdated (and too big in this case) if some subprogs are completely removed during dead code elimination (in adjust_subprog_starts_after_remove). The cached index in insn[1].imm is not updated accordingly and causing out-of-bound issue in the later jit_subprog(). Unlike bpf_pseudo_'func' insn, the current bpf_pseudo_'call' insn is handling the DCE properly by calling find_subprog(insn->imm) to figure out the index instead of caching the subprog index. The existing bpf_adj_branches() will adjust the insn->imm whenever insn is added or removed. Instead of having two ways handling subprog index, this patch is to make bpf_pseudo_func works more like bpf_pseudo_call. First change is to stop caching the subprog index result in insn[1].imm after add_subprog(). The verification process will use find_subprog(insn->imm) to figure out the subprog index. Second change is in bpf_adj_branches() and have it to adjust the insn->imm for the bpf_pseudo_func insn also whenever insn is added or removed. Third change is in jit_subprog(). Like the bpf_pseudo_call handling, bpf_pseudo_func temporarily stores the find_subprog() result in insn->off. It is fine because the prog's insn has been finalized at this point. insn->off will be reset back to 0 later to avoid confusing the userspace prog dump tool. Fixes: 69c087ba6225 ("bpf: Add bpf_for_each_map_elem() helper") Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211106014014.651018-1-kafai@fb.com
2021-11-03bpf: Do not reject when the stack read size is different from the tracked scalar sizeMartin KaFai Lau1-12/+6
Below is a simplified case from a report in bcc [0]: r4 = 20 *(u32 *)(r10 -4) = r4 *(u32 *)(r10 -8) = r4 /* r4 state is tracked */ r4 = *(u64 *)(r10 -8) /* Read more than the tracked 32bit scalar. * verifier rejects as 'corrupted spill memory'. */ After commit 354e8f1970f8 ("bpf: Support <8-byte scalar spill and refill"), the 8-byte aligned 32bit spill is also tracked by the verifier and the register state is stored. However, if 8 bytes are read from the stack instead of the tracked 4 byte scalar, then verifier currently rejects the program as "corrupted spill memory". This patch fixes this case by allowing it to read but marks the register as unknown. Also note that, if the prog is trying to corrupt/leak an earlier spilled pointer by spilling another <8 bytes register on top, this has already been rejected in the check_stack_write_fixed_off(). [0] https://github.com/iovisor/bcc/pull/3683 Fixes: 354e8f1970f8 ("bpf: Support <8-byte scalar spill and refill") Reported-by: Hengqi Chen <hengqi.chen@gmail.com> Reported-by: Yonghong Song <yhs@gmail.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Hengqi Chen <hengqi.chen@gmail.com> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20211102064535.316018-1-kafai@fb.com
2021-11-02Merge branch 'for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroupLinus Torvalds1-9/+45
Pull cgroup updates from Tejun Heo: - The misc controller now reports allocation rejections through misc.events instead of printking - cgroup_mutex usage is reduced to improve scalability of some operations - vhost helper threads are now assigned to the right cgroup on cgroup2 - Bug fixes * 'for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: bpf: Move wrapper for __cgroup_bpf_*() to kernel/bpf/cgroup.c cgroup: Fix rootcg cpu.stat guest double counting cgroup: no need for cgroup_mutex for /proc/cgroups cgroup: remove cgroup_mutex from cgroupstats_build cgroup: reduce dependency on cgroup_mutex cgroup: cgroup-v1: do not exclude cgrp_dfl_root cgroup: Make rebind_subsystems() disable v2 controllers all at once docs/cgroup: add entry for misc.events misc_cgroup: remove error log to avoid log flood misc_cgroup: introduce misc.events to count failures
2021-11-02Merge tag 'net-next-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds16-143/+861
Pull networking updates from Jakub Kicinski: "Core: - Remove socket skb caches - Add a SO_RESERVE_MEM socket op to forward allocate buffer space and avoid memory accounting overhead on each message sent - Introduce managed neighbor entries - added by control plane and resolved by the kernel for use in acceleration paths (BPF / XDP right now, HW offload users will benefit as well) - Make neighbor eviction on link down controllable by userspace to work around WiFi networks with bad roaming implementations - vrf: Rework interaction with netfilter/conntrack - fq_codel: implement L4S style ce_threshold_ect1 marking - sch: Eliminate unnecessary RCU waits in mini_qdisc_pair_swap() BPF: - Add support for new btf kind BTF_KIND_TAG, arbitrary type tagging as implemented in LLVM14 - Introduce bpf_get_branch_snapshot() to capture Last Branch Records - Implement variadic trace_printk helper - Add a new Bloomfilter map type - Track <8-byte scalar spill and refill - Access hw timestamp through BPF's __sk_buff - Disallow unprivileged BPF by default - Document BPF licensing Netfilter: - Introduce egress hook for looking at raw outgoing packets - Allow matching on and modifying inner headers / payload data - Add NFT_META_IFTYPE to match on the interface type either from ingress or egress Protocols: - Multi-Path TCP: - increase default max additional subflows to 2 - rework forward memory allocation - add getsockopts: MPTCP_INFO, MPTCP_TCPINFO, MPTCP_SUBFLOW_ADDRS - MCTP flow support allowing lower layer drivers to configure msg muxing as needed - Automatic Multicast Tunneling (AMT) driver based on RFC7450 - HSR support the redbox supervision frames (IEC-62439-3:2018) - Support for the ip6ip6 encapsulation of IOAM - Netlink interface for CAN-FD's Transmitter Delay Compensation - Support SMC-Rv2 eliminating the current same-subnet restriction, by exploiting the UDP encapsulation feature of RoCE adapters - TLS: add SM4 GCM/CCM crypto support - Bluetooth: initial support for link quality and audio/codec offload Driver APIs: - Add a batched interface for RX buffer allocation in AF_XDP buffer pool - ethtool: Add ability to control transceiver modules' power mode - phy: Introduce supported interfaces bitmap to express MAC capabilities and simplify PHY code - Drop rtnl_lock from DSA .port_fdb_{add,del} callbacks New drivers: - WiFi driver for Realtek 8852AE 802.11ax devices (rtw89) - Ethernet driver for ASIX AX88796C SPI device (x88796c) Drivers: - Broadcom PHYs - support 72165, 7712 16nm PHYs - support IDDQ-SR for additional power savings - PHY support for QCA8081, QCA9561 PHYs - NXP DPAA2: support for IRQ coalescing - NXP Ethernet (enetc): support for software TCP segmentation - Renesas Ethernet (ravb) - support DMAC and EMAC blocks of Gigabit-capable IP found on RZ/G2L SoC - Intel 100G Ethernet - support for eswitch offload of TC/OvS flow API, including offload of GRE, VxLAN, Geneve tunneling - support application device queues - ability to assign Rx and Tx queues to application threads - PTP and PPS (pulse-per-second) extensions - Broadcom Ethernet (bnxt) - devlink health reporting and device reload extensions - Mellanox Ethernet (mlx5) - offload macvlan interfaces - support HW offload of TC rules involving OVS internal ports - support HW-GRO and header/data split - support application device queues - Marvell OcteonTx2: - add XDP support for PF - add PTP support for VF - Qualcomm Ethernet switch (qca8k): support for QCA8328 - Realtek Ethernet DSA switch (rtl8366rb) - support bridge offload - support STP, fast aging, disabling address learning - support for Realtek RTL8365MB-VC, a 4+1 port 10M/100M/1GE switch - Mellanox Ethernet/IB switch (mlxsw) - multi-level qdisc hierarchy offload (e.g. RED, prio and shaping) - offload root TBF qdisc as port shaper - support multiple routing interface MAC address prefixes - support for IP-in-IP with IPv6 underlay - MediaTek WiFi (mt76) - mt7921 - ASPM, 6GHz, SDIO and testmode support - mt7915 - LED and TWT support - Qualcomm WiFi (ath11k) - include channel rx and tx time in survey dump statistics - support for 80P80 and 160 MHz bandwidths - support channel 2 in 6 GHz band - spectral scan support for QCN9074 - support for rx decapsulation offload (data frames in 802.3 format) - Qualcomm phone SoC WiFi (wcn36xx) - enable Idle Mode Power Save (IMPS) to reduce power consumption during idle - Bluetooth driver support for MediaTek MT7922 and MT7921 - Enable support for AOSP Bluetooth extension in Qualcomm WCN399x and Realtek 8822C/8852A - Microsoft vNIC driver (mana) - support hibernation and kexec - Google vNIC driver (gve) - support for jumbo frames - implement Rx page reuse Refactor: - Make all writes to netdev->dev_addr go thru helpers, so that we can add this address to the address rbtree and handle the updates - Various TCP cleanups and optimizations including improvements to CPU cache use - Simplify the gnet_stats, Qdisc stats' handling and remove qdisc->running sequence counter - Driver changes and API updates to address devlink locking deficiencies" * tag 'net-next-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2122 commits) Revert "net: avoid double accounting for pure zerocopy skbs" selftests: net: add arp_ndisc_evict_nocarrier net: ndisc: introduce ndisc_evict_nocarrier sysctl parameter net: arp: introduce arp_evict_nocarrier sysctl parameter libbpf: Deprecate AF_XDP support kbuild: Unify options for BTF generation for vmlinux and modules selftests/bpf: Add a testcase for 64-bit bounds propagation issue. bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit. bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off. net: vmxnet3: remove multiple false checks in vmxnet3_ethtool.c net: avoid double accounting for pure zerocopy skbs tcp: rename sk_wmem_free_skb netdevsim: fix uninit value in nsim_drv_configure_vfs() selftests/bpf: Fix also no-alu32 strobemeta selftest bpf: Add missing map_delete_elem method to bloom filter map selftests/bpf: Add bloom map success test for userspace calls bpf: Add alignment padding for "map_extra" + consolidate holes bpf: Bloom filter map naming fixups selftests/bpf: Add test cases for struct_ops prog bpf: Add dummy BPF STRUCT_OPS for test purpose ...
2021-11-01Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski13-106/+656
Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-11-01 We've added 181 non-merge commits during the last 28 day(s) which contain a total of 280 files changed, 11791 insertions(+), 5879 deletions(-). The main changes are: 1) Fix bpf verifier propagation of 64-bit bounds, from Alexei. 2) Parallelize bpf test_progs, from Yucong and Andrii. 3) Deprecate various libbpf apis including af_xdp, from Andrii, Hengqi, Magnus. 4) Improve bpf selftests on s390, from Ilya. 5) bloomfilter bpf map type, from Joanne. 6) Big improvements to JIT tests especially on Mips, from Johan. 7) Support kernel module function calls from bpf, from Kumar. 8) Support typeless and weak ksym in light skeleton, from Kumar. 9) Disallow unprivileged bpf by default, from Pawan. 10) BTF_KIND_DECL_TAG support, from Yonghong. 11) Various bpftool cleanups, from Quentin. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (181 commits) libbpf: Deprecate AF_XDP support kbuild: Unify options for BTF generation for vmlinux and modules selftests/bpf: Add a testcase for 64-bit bounds propagation issue. bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit. bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off. selftests/bpf: Fix also no-alu32 strobemeta selftest bpf: Add missing map_delete_elem method to bloom filter map selftests/bpf: Add bloom map success test for userspace calls bpf: Add alignment padding for "map_extra" + consolidate holes bpf: Bloom filter map naming fixups selftests/bpf: Add test cases for struct_ops prog bpf: Add dummy BPF STRUCT_OPS for test purpose bpf: Factor out helpers for ctx access checking bpf: Factor out a helper to prepare trampoline for struct_ops prog selftests, bpf: Fix broken riscv build riscv, libbpf: Add RISC-V (RV64) support to bpf_tracing.h tools, build: Add RISC-V to HOSTARCH parsing riscv, bpf: Increase the maximum number of iterations selftests, bpf: Add one test for sockmap with strparser selftests, bpf: Fix test_txmsg_ingress_parser error ... ==================== Link: https://lore.kernel.org/r/20211102013123.9005-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit.Alexei Starovoitov1-1/+1
Similar to unsigned bounds propagation fix signed bounds. The 'Fixes' tag is a hint. There is no security bug here. The verifier was too conservative. Fixes: 3f50f132d840 ("bpf: Verifier, do explicit ALU32 bounds tracking") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20211101222153.78759-2-alexei.starovoitov@gmail.com
2021-11-01bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off.Alexei Starovoitov1-1/+1
Before this fix: 166: (b5) if r2 <= 0x1 goto pc+22 from 166 to 189: R2=invP(id=1,umax_value=1,var_off=(0x0; 0xffffffff)) After this fix: 166: (b5) if r2 <= 0x1 goto pc+22 from 166 to 189: R2=invP(id=1,umax_value=1,var_off=(0x0; 0x1)) While processing BPF_JLE the reg_set_min_max() would set true_reg->umax_value = 1 and call __reg_combine_64_into_32(true_reg). Without the fix it would not pass the condition: if (__reg64_bound_u32(reg->umin_value) && __reg64_bound_u32(reg->umax_value)) since umin_value == 0 at this point. Before commit 10bf4e83167c the umin was incorrectly ingored. The commit 10bf4e83167c fixed the correctness issue, but pessimized propagation of 64-bit min max into 32-bit min max and corresponding var_off. Fixes: 10bf4e83167c ("bpf: Fix propagation of 32 bit unsigned bounds from 64 bit bounds") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20211101222153.78759-1-alexei.starovoitov@gmail.com
2021-11-01bpf: Add missing map_delete_elem method to bloom filter mapEric Dumazet1-0/+6
Without it, kernel crashes in map_delete_elem(), as reported by syzbot. BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 72c97067 P4D 72c97067 PUD 1e20c067 PMD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 0 PID: 6518 Comm: syz-executor196 Not tainted 5.15.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:0x0 Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. RSP: 0018:ffffc90002bafcb8 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 1ffff92000575f9f RCX: 0000000000000000 RDX: 1ffffffff1327aba RSI: 0000000000000000 RDI: ffff888025a30c00 RBP: ffffc90002baff08 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff818525d8 R11: 0000000000000000 R12: ffffffff8993d560 R13: ffff888025a30c00 R14: ffff888024bc0000 R15: 0000000000000000 FS: 0000555557491300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 0000000070189000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: map_delete_elem kernel/bpf/syscall.c:1220 [inline] __sys_bpf+0x34f1/0x5ee0 kernel/bpf/syscall.c:4606 __do_sys_bpf kernel/bpf/syscall.c:4719 [inline] __se_sys_bpf kernel/bpf/syscall.c:4717 [inline] __x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:4717 do_syscall_x64 arch/x86/entry/common.c:50 [inline] Fixes: 9330986c0300 ("bpf: Add bloom filter map implementation") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20211031171353.4092388-1-eric.dumazet@gmail.com
2021-11-01bpf: Bloom filter map naming fixupsJoanne Koong1-23/+26
This patch has two changes in the kernel bloom filter map implementation: 1) Change the names of map-ops functions to include the "bloom_map" prefix. As Martin pointed out on a previous patchset, having generic map-ops names may be confusing in tracing and in perf-report. 2) Drop the "& 0xF" when getting nr_hash_funcs, since we already ascertain that no other bits in map_extra beyond the first 4 bits can be set. Signed-off-by: Joanne Koong <joannekoong@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20211029224909.1721024-2-joannekoong@fb.com
2021-11-01bpf: Add dummy BPF STRUCT_OPS for test purposeHou Tao2-0/+6
Currently the test of BPF STRUCT_OPS depends on the specific bpf implementation of tcp_congestion_ops, but it can not cover all basic functionalities (e.g, return value handling), so introduce a dummy BPF STRUCT_OPS for test purpose. Loading a bpf_dummy_ops implementation from userspace is prohibited, and its only purpose is to run BPF_PROG_TYPE_STRUCT_OPS program through bpf(BPF_PROG_TEST_RUN). Now programs for test_1() & test_2() are supported. The following three cases are exercised in bpf_dummy_struct_ops_test_run(): (1) test and check the value returned from state arg in test_1(state) The content of state is copied from userspace pointer and copied back after calling test_1(state). The user pointer is saved in an u64 array and the array address is passed through ctx_in. (2) test and check the return value of test_1(NULL) Just simulate the case in which an invalid input argument is passed in. (3) test multiple arguments passing in test_2(state, ...) 5 arguments are passed through ctx_in in form of u64 array. The first element of array is userspace pointer of state and others 4 arguments follow. Signed-off-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20211025064025.2567443-4-houtao1@huawei.com
2021-11-01bpf: Factor out a helper to prepare trampoline for struct_ops progHou Tao1-10/+19
Factor out a helper bpf_struct_ops_prepare_trampoline() to prepare trampoline for BPF_PROG_TYPE_STRUCT_OPS prog. It will be used by .test_run callback in following patch. Signed-off-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20211025064025.2567443-2-houtao1@huawei.com
2021-11-01cgroup: bpf: Move wrapper for __cgroup_bpf_*() to kernel/bpf/cgroup.cHe Fengqing1-9/+45
In commit 324bda9e6c5a("bpf: multi program support for cgroup+bpf") cgroup_bpf_*() called from kernel/bpf/syscall.c, but now they are only used in kernel/bpf/cgroup.c, so move these function to kernel/bpf/cgroup.c, like cgroup_bpf_replace(). Signed-off-by: He Fengqing <hefengqing@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-11-01bpf: Disallow unprivileged bpf by defaultPawan Gupta1-0/+7
Disabling unprivileged BPF would help prevent unprivileged users from creating certain conditions required for potential speculative execution side-channel attacks on unmitigated affected hardware. A deep dive on such attacks and current mitigations is available here [0]. Sync with what many distros are currently applying already, and disable unprivileged BPF by default. An admin can enable this at runtime, if necessary, as described in 08389d888287 ("bpf: Add kconfig knob for disabling unpriv bpf by default"). [0] "BPF and Spectre: Mitigating transient execution attacks", Daniel Borkmann, eBPF Summit '21 https://ebpf.io/summit-2021-slides/eBPF_Summit_2021-Keynote-Daniel_Borkmann-BPF_and_Spectre.pdf Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/bpf/0ace9ce3f97656d5f62d11093ad7ee81190c3c25.1635535215.git.pawan.kumar.gupta@linux.intel.com
2021-11-01Merge tag 'folio-5.16' of git://git.infradead.org/users/willy/pagecacheLinus Torvalds1-1/+1
Pull memory folios from Matthew Wilcox: "Add memory folios, a new type to represent either order-0 pages or the head page of a compound page. This should be enough infrastructure to support filesystems converting from pages to folios. The point of all this churn is to allow filesystems and the page cache to manage memory in larger chunks than PAGE_SIZE. The original plan was to use compound pages like THP does, but I ran into problems with some functions expecting only a head page while others expect the precise page containing a particular byte. The folio type allows a function to declare that it's expecting only a head page. Almost incidentally, this allows us to remove various calls to VM_BUG_ON(PageTail(page)) and compound_head(). This converts just parts of the core MM and the page cache. For 5.17, we intend to convert various filesystems (XFS and AFS are ready; other filesystems may make it) and also convert more of the MM and page cache to folios. For 5.18, multi-page folios should be ready. The multi-page folios offer some improvement to some workloads. The 80% win is real, but appears to be an artificial benchmark (postgres startup, which isn't a serious workload). Real workloads (eg building the kernel, running postgres in a steady state, etc) seem to benefit between 0-10%. I haven't heard of any performance losses as a result of this series. Nobody has done any serious performance tuning; I imagine that tweaking the readahead algorithm could provide some more interesting wins. There are also other places where we could choose to create large folios and currently do not, such as writes that are larger than PAGE_SIZE. I'd like to thank all my reviewers who've offered review/ack tags: Christoph Hellwig, David Howells, Jan Kara, Jeff Layton, Johannes Weiner, Kirill A. Shutemov, Michal Hocko, Mike Rapoport, Vlastimil Babka, William Kucharski, Yu Zhao and Zi Yan. I'd also like to thank those who gave feedback I incorporated but haven't offered up review tags for this part of the series: Nick Piggin, Mel Gorman, Ming Lei, Darrick Wong, Ted Ts'o, John Hubbard, Hugh Dickins, and probably a few others who I forget" * tag 'folio-5.16' of git://git.infradead.org/users/willy/pagecache: (90 commits) mm/writeback: Add folio_write_one mm/filemap: Add FGP_STABLE mm/filemap: Add filemap_get_folio mm/filemap: Convert mapping_get_entry to return a folio mm/filemap: Add filemap_add_folio() mm/filemap: Add filemap_alloc_folio mm/page_alloc: Add folio allocation functions mm/lru: Add folio_add_lru() mm/lru: Convert __pagevec_lru_add_fn to take a folio mm: Add folio_evictable() mm/workingset: Convert workingset_refault() to take a folio mm/filemap: Add readahead_folio() mm/filemap: Add folio_mkwrite_check_truncate() mm/filemap: Add i_blocks_per_folio() mm/writeback: Add folio_redirty_for_writepage() mm/writeback: Add folio_account_redirty() mm/writeback: Add folio_clear_dirty_for_io() mm/writeback: Add folio_cancel_dirty() mm/writeback: Add folio_account_cleaned() mm/writeback: Add filemap_dirty_folio() ...
2021-10-28bpf: Add bpf_kallsyms_lookup_name helperKumar Kartikeya Dwivedi1-0/+27
This helper allows us to get the address of a kernel symbol from inside a BPF_PROG_TYPE_SYSCALL prog (used by gen_loader), so that we can relocate typeless ksym vars. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20211028063501.2239335-2-memxor@gmail.com
2021-10-28bpf: Add bloom filter map implementationJoanne Koong4-7/+233
This patch adds the kernel-side changes for the implementation of a bpf bloom filter map. The bloom filter map supports peek (determining whether an element is present in the map) and push (adding an element to the map) operations.These operations are exposed to userspace applications through the already existing syscalls in the following way: BPF_MAP_LOOKUP_ELEM -> peek BPF_MAP_UPDATE_ELEM -> push The bloom filter map does not have keys, only values. In light of this, the bloom filter map's API matches that of queue stack maps: user applications use BPF_MAP_LOOKUP_ELEM/BPF_MAP_UPDATE_ELEM which correspond internally to bpf_map_peek_elem/bpf_map_push_elem, and bpf programs must use the bpf_map_peek_elem and bpf_map_push_elem APIs to query or add an element to the bloom filter map. When the bloom filter map is created, it must be created with a key_size of 0. For updates, the user will pass in the element to add to the map as the value, with a NULL key. For lookups, the user will pass in the element to query in the map as the value, with a NULL key. In the verifier layer, this requires us to modify the argument type of a bloom filter's BPF_FUNC_map_peek_elem call to ARG_PTR_TO_MAP_VALUE; as well, in the syscall layer, we need to copy over the user value so that in bpf_map_peek_elem, we know which specific value to query. A few things to please take note of: * If there are any concurrent lookups + updates, the user is responsible for synchronizing this to ensure no false negative lookups occur. * The number of hashes to use for the bloom filter is configurable from userspace. If no number is specified, the default used will be 5 hash functions. The benchmarks later in this patchset can help compare the performance of using different number of hashes on different entry sizes. In general, using more hashes decreases both the false positive rate and the speed of a lookup. * Deleting an element in the bloom filter map is not supported. * The bloom filter map may be used as an inner map. * The "max_entries" size that is specified at map creation time is used to approximate a reasonable bitmap size for the bloom filter, and is not otherwise strictly enforced. If the user wishes to insert more entries into the bloom filter than "max_entries", they may do so but they should be aware that this may lead to a higher false positive rate. Signed-off-by: Joanne Koong <joannekoong@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211027234504.30744-2-joannekoong@fb.com
2021-10-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-12/+24
include/net/sock.h 7b50ecfcc6cd ("net: Rename ->stream_memory_read to ->sock_is_readable") 4c1e34c0dbff ("vsock: Enable y2038 safe timeval for timeout") drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c 0daa55d033b0 ("octeontx2-af: cn10k: debugfs for dumping LMTST map table") e77bcdd1f639 ("octeontx2-af: Display all enabled PF VF rsrc_alloc entries.") Adjacent code addition in both cases, keep both. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-27bpf: Use u64_stats_t in struct bpf_prog_statsEric Dumazet2-9/+15
Commit 316580b69d0a ("u64_stats: provide u64_stats_t type") fixed possible load/store tearing on 64bit arches. For instance the following C code stats->nsecs += sched_clock() - start; Could be rightfully implemented like this by a compiler, confusing concurrent readers a lot: stats->nsecs += sched_clock(); // arbitrary delay stats->nsecs -= start; Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211026214133.3114279-4-eric.dumazet@gmail.com
2021-10-27bpf: Fixes possible race in update_prog_stats() for 32bit archesEric Dumazet1-2/+4
It seems update_prog_stats() suffers from same issue fixed in the prior patch: As it can run while interrupts are enabled, it could be re-entered and the u64_stats syncp could be mangled. Fixes: fec56f5890d9 ("bpf: Introduce BPF trampoline") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211026214133.3114279-3-eric.dumazet@gmail.com
2021-10-26bpf: Fix potential race in tail call compatibility checkToke Høiland-Jørgensen3-9/+18
Lorenzo noticed that the code testing for program type compatibility of tail call maps is potentially racy in that two threads could encounter a map with an unset type simultaneously and both return true even though they are inserting incompatible programs. The race window is quite small, but artificially enlarging it by adding a usleep_range() inside the check in bpf_prog_array_compatible() makes it trivial to trigger from userspace with a program that does, essentially: map_fd = bpf_create_map(BPF_MAP_TYPE_PROG_ARRAY, 4, 4, 2, 0); pid = fork(); if (pid) { key = 0; value = xdp_fd; } else { key = 1; value = tc_fd; } err = bpf_map_update_elem(map_fd, &key, &value, 0); While the race window is small, it has potentially serious ramifications in that triggering it would allow a BPF program to tail call to a program of a different type. So let's get rid of it by protecting the update with a spinlock. The commit in the Fixes tag is the last commit that touches the code in question. v2: - Use a spinlock instead of an atomic variable and cmpxchg() (Alexei) v3: - Put lock and the members it protects into an embedded 'owner' struct (Daniel) Fixes: 3324b584b6f6 ("ebpf: misc core cleanup") Reported-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211026110019.363464-1-toke@redhat.com
2021-10-22bpf: Fix error usage of map_fd and fdget() in generic_map_update_batch()Xu Kuohai1-2/+3
1. The ufd in generic_map_update_batch() should be read from batch.map_fd; 2. A call to fdget() should be followed by a symmetric call to fdput(). Fixes: aa2e93b8e58e ("bpf: Add generic support for update and delete batch ops") Signed-off-by: Xu Kuohai <xukuohai@huawei.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211019032934.1210517-1-xukuohai@huawei.com
2021-10-22bpf: Prevent increasing bpf_jit_limit above maxLorenz Bauer1-1/+3
Restrict bpf_jit_limit to the maximum supported by the arch's JIT. Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211014142554.53120-4-lmb@cloudflare.com
2021-10-22bpf: Add BTF_KIND_DECL_TAG typedef supportYonghong Song1-2/+2
The llvm patches ([1], [2]) added support to attach btf_decl_tag attributes to typedef declarations. This patch added support in kernel. [1] https://reviews.llvm.org/D110127 [2] https://reviews.llvm.org/D112259 Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211021195628.4018847-1-yhs@fb.com
2021-10-21bpf: Add verified_insns to bpf_prog_info and fdinfoDave Marchevsky2-2/+7
This stat is currently printed in the verifier log and not stored anywhere. To ease consumption of this data, add a field to bpf_prog_aux so it can be exposed via BPF_OBJ_GET_INFO_BY_FD and fdinfo. Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20211020074818.1017682-2-davemarchevsky@fb.com
2021-10-20bpf/preload: Clean up .gitignore and "clean-files" targetQuentin Monnet2-5/+2
kernel/bpf/preload/Makefile was recently updated to have it install libbpf's headers locally instead of pulling them from tools/lib/bpf. But two items still need to be addressed. First, the local .gitignore file was not adjusted to ignore the files generated in the new kernel/bpf/preload/libbpf output directory. Second, the "clean-files" target is now incorrect. The old artefacts names were not removed from the target, while the new ones were added incorrectly. This is because "clean-files" expects names relative to $(obj), but we passed the absolute path instead. This results in the output and header-destination directories for libbpf (and their contents) not being removed from kernel/bpf/preload on "make clean" from the root of the repository. This commit fixes both issues. Note that $(userprogs) needs not be added to "clean-files", because the cleaning infrastructure already accounts for it. Cleaning the files properly also prevents make from printing the following message, for builds coming after a "make clean": "make[4]: Nothing to be done for 'install_headers'." v2: Simplify the "clean-files" target. Fixes: bf60791741d4 ("bpf: preload: Install libbpf headers when building") Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20211020094647.15564-1-quentin@isovalent.com
2021-10-19bpf: Silence Coverity warning for find_kfunc_desc_btfKumar Kartikeya Dwivedi1-9/+4
The helper function returns a pointer that in the failure case encodes an error in the struct btf pointer. The current code lead to Coverity warning about the use of the invalid pointer: *** CID 1507963: Memory - illegal accesses (USE_AFTER_FREE) /kernel/bpf/verifier.c: 1788 in find_kfunc_desc_btf() 1782 return ERR_PTR(-EINVAL); 1783 } 1784 1785 kfunc_btf = __find_kfunc_desc_btf(env, offset, btf_modp); 1786 if (IS_ERR_OR_NULL(kfunc_btf)) { 1787 verbose(env, "cannot find module BTF for func_id %u\n", func_id); >>> CID 1507963: Memory - illegal accesses (USE_AFTER_FREE) >>> Using freed pointer "kfunc_btf". 1788 return kfunc_btf ?: ERR_PTR(-ENOENT); 1789 } 1790 return kfunc_btf; 1791 } 1792 return btf_vmlinux ?: ERR_PTR(-ENOENT); 1793 } Daniel suggested the use of ERR_CAST so that the intended use is clear to Coverity, but on closer look it seems that we never return NULL from the helper. Andrii noted that since __find_kfunc_desc_btf already logs errors for all cases except btf_get_by_fd, it is much easier to add logging for that and remove the IS_ERR check altogether, returning directly from it. Suggested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211009040900.803436-1-memxor@gmail.com
2021-10-18bpf: Rename BTF_KIND_TAG to BTF_KIND_DECL_TAGYonghong Song1-22/+22
Patch set [1] introduced BTF_KIND_TAG to allow tagging declarations for struct/union, struct/union field, var, func and func arguments and these tags will be encoded into dwarf. They are also encoded to btf by llvm for the bpf target. After BTF_KIND_TAG is introduced, we intended to use it for kernel __user attributes. But kernel __user is actually a type attribute. Upstream and internal discussion showed it is not a good idea to mix declaration attribute and type attribute. So we proposed to introduce btf_type_tag as a type attribute and existing btf_tag renamed to btf_decl_tag ([2]). This patch renamed BTF_KIND_TAG to BTF_KIND_DECL_TAG and some other declarations with *_tag to *_decl_tag to make it clear the tag is for declaration. In the future, BTF_KIND_TYPE_TAG might be introduced per [3]. [1] https://lore.kernel.org/bpf/20210914223004.244411-1-yhs@fb.com/ [2] https://reviews.llvm.org/D111588 [3] https://reviews.llvm.org/D111199 Fixes: b5ea834dde6b ("bpf: Support for new btf kind BTF_KIND_TAG") Fixes: 5b84bd10363e ("libbpf: Add support for BTF_KIND_TAG") Fixes: 5c07f2fec003 ("bpftool: Add support for BTF_KIND_TAG") Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211012164838.3345699-1-yhs@fb.com
2021-10-18mm/filemap: Add filemap_add_folio()Matthew Wilcox (Oracle)1-1/+1
Convert __add_to_page_cache_locked() into __filemap_add_folio(). Add an assertion to it that (for !hugetlbfs), the folio is naturally aligned within the file. Move the prototype from mm.h to pagemap.h. Convert add_to_page_cache_lru() into filemap_add_folio(). Add a compatibility wrapper for unconverted callers. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Howells <dhowells@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz>
2021-10-08bpftool: Add install-bin target to install binary onlyQuentin Monnet1-1/+1
With "make install", bpftool installs its binary and its bash completion file. Usually, this is what we want. But a few components in the kernel repository (namely, BPF iterators and selftests) also install bpftool locally before using it. In such a case, bash completion is not necessary and is just a useless build artifact. Let's add an "install-bin" target to bpftool, to offer a way to install the binary only. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211007194438.34443-13-quentin@isovalent.com
2021-10-08bpf: iterators: Install libbpf headers when buildingQuentin Monnet1-13/+25
API headers from libbpf should not be accessed directly from the library's source directory. Instead, they should be exported with "make install_headers". Let's make sure that bpf/preload/iterators/Makefile installs the headers properly when building. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211007194438.34443-8-quentin@isovalent.com
2021-10-08bpf: preload: Install libbpf headers when buildingQuentin Monnet1-5/+20
API headers from libbpf should not be accessed directly from the library's source directory. Instead, they should be exported with "make install_headers". Let's make sure that bpf/preload/Makefile installs the headers properly when building. Note that we declare an additional dependency for iterators/iterators.o: having $(LIBBPF_A) as a dependency to "$(obj)/bpf_preload_umd" is not sufficient, as it makes it required only at the linking step. But we need libbpf to be compiled, and in particular its headers to be exported, before we attempt to compile iterators.o. The issue would not occur before this commit, because libbpf's headers were not exported and were always available under tools/lib/bpf. Signed-off-by: Quentin Monnet <quentin@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20211007194438.34443-7-quentin@isovalent.com
2021-10-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+2
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-05bpf: Avoid retpoline for bpf_for_each_map_elemAndrey Ignatov1-1/+10
Similarly to 09772d92cd5a ("bpf: avoid retpoline for lookup/update/delete calls on maps") and 84430d4232c3 ("bpf, verifier: avoid retpoline for map push/pop/peek operation") avoid indirect call while calling bpf_for_each_map_elem. Before (a program fragment): ; if (rules_map) { 142: (15) if r4 == 0x0 goto pc+8 143: (bf) r3 = r10 ; bpf_for_each_map_elem(rules_map, process_each_rule, &ctx, 0); 144: (07) r3 += -24 145: (bf) r1 = r4 146: (18) r2 = subprog[+5] 148: (b7) r4 = 0 149: (85) call bpf_for_each_map_elem#143680 <-- indirect call via helper After (same program fragment): ; if (rules_map) { 142: (15) if r4 == 0x0 goto pc+8 143: (bf) r3 = r10 ; bpf_for_each_map_elem(rules_map, process_each_rule, &ctx, 0); 144: (07) r3 += -24 145: (bf) r1 = r4 146: (18) r2 = subprog[+5] 148: (b7) r4 = 0 149: (85) call bpf_for_each_array_elem#170336 <-- direct call On a benchmark that calls bpf_for_each_map_elem() once and does many other things (mostly checking fields in skb) with CONFIG_RETPOLINE=y it makes program faster. Before: ============================================================================ Benchmark.cpp time/iter iters/s ============================================================================ IngressMatchByRemoteEndpoint 80.78ns 12.38M IngressMatchByRemoteIP 80.66ns 12.40M IngressMatchByRemotePort 80.87ns 12.37M After: ============================================================================ Benchmark.cpp time/iter iters/s ============================================================================ IngressMatchByRemoteEndpoint 73.49ns 13.61M IngressMatchByRemoteIP 71.48ns 13.99M IngressMatchByRemotePort 70.39ns 14.21M Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211006001838.75607-1-rdna@fb.com
2021-10-05bpf: selftests: Add selftests for module kfunc supportKumar Kartikeya Dwivedi1-0/+1
This adds selftests that tests the success and failure path for modules kfuncs (in presence of invalid kfunc calls) for both libbpf and gen_loader. It also adds a prog_test kfunc_btf_id_list so that we can add module BTF ID set from bpf_testmod. This also introduces a couple of test cases to verifier selftests for validating whether we get an error or not depending on if invalid kfunc call remains after elimination of unreachable instructions. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211002011757.311265-10-memxor@gmail.com
2021-10-05bpf: Enable TCP congestion control kfunc from modulesKumar Kartikeya Dwivedi1-0/+2
This commit moves BTF ID lookup into the newly added registration helper, in a way that the bbr, cubic, and dctcp implementation set up their sets in the bpf_tcp_ca kfunc_btf_set list, while the ones not dependent on modules are looked up from the wrapper function. This lifts the restriction for them to be compiled as built in objects, and can be loaded as modules if required. Also modify Makefile.modfinal to call resolve_btfids for each module. Note that since kernel kfunc_ids never overlap with module kfunc_ids, we only match the owner for module btf id sets. See following commits for background on use of: CONFIG_X86 ifdef: 569c484f9995 (bpf: Limit static tcp-cc functions in the .BTF_ids list to x86) CONFIG_DYNAMIC_FTRACE ifdef: 7aae231ac93b (bpf: tcp: Limit calling some tcp cc functions to CONFIG_DYNAMIC_FTRACE) Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211002011757.311265-6-memxor@gmail.com
2021-10-05bpf: btf: Introduce helpers for dynamic BTF set registrationKumar Kartikeya Dwivedi1-0/+52
This adds helpers for registering btf_id_set from modules and the bpf_check_mod_kfunc_call callback that can be used to look them up. With in kernel sets, the way this is supposed to work is, in kernel callback looks up within the in-kernel kfunc whitelist, and then defers to the dynamic BTF set lookup if it doesn't find the BTF id. If there is no in-kernel BTF id set, this callback can be used directly. Also fix includes for btf.h and bpfptr.h so that they can included in isolation. This is in preparation for their usage in tcp_bbr, tcp_cubic and tcp_dctcp modules in the next patch. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211002011757.311265-4-memxor@gmail.com
2021-10-05bpf: Be conservative while processing invalid kfunc callsKumar Kartikeya Dwivedi1-0/+18
This patch also modifies the BPF verifier to only return error for invalid kfunc calls specially marked by userspace (with insn->imm == 0, insn->off == 0) after the verifier has eliminated dead instructions. This can be handled in the fixup stage, and skip processing during add and check stages. If such an invalid call is dropped, the fixup stage will not encounter insn->imm as 0, otherwise it bails out and returns an error. This will be exposed as weak ksym support in libbpf in later patches. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211002011757.311265-3-memxor@gmail.com
2021-10-05bpf: Introduce BPF support for kernel module function callsKumar Kartikeya Dwivedi2-27/+179
This change adds support on the kernel side to allow for BPF programs to call kernel module functions. Userspace will prepare an array of module BTF fds that is passed in during BPF_PROG_LOAD using fd_array parameter. In the kernel, the module BTFs are placed in the auxilliary struct for bpf_prog, and loaded as needed. The verifier then uses insn->off to index into the fd_array. insn->off 0 is reserved for vmlinux BTF (for backwards compat), so userspace must use an fd_array index > 0 for module kfunc support. kfunc_btf_tab is sorted based on offset in an array, and each offset corresponds to one descriptor, with a max limit up to 256 such module BTFs. We also change existing kfunc_tab to distinguish each element based on imm, off pair as each such call will now be distinct. Another change is to check_kfunc_call callback, which now include a struct module * pointer, this is to be used in later patch such that the kfunc_id and module pointer are matched for dynamically registered BTF sets from loadable modules, so that same kfunc_id in two modules doesn't lead to check_kfunc_call succeeding. For the duration of the check_kfunc_call, the reference to struct module exists, as it returns the pointer stored in kfunc_btf_tab. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211002011757.311265-2-memxor@gmail.com
2021-10-01Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski5-60/+99
Daniel Borkmann says: ==================== bpf-next 2021-10-02 We've added 85 non-merge commits during the last 15 day(s) which contain a total of 132 files changed, 13779 insertions(+), 6724 deletions(-). The main changes are: 1) Massive update on test_bpf.ko coverage for JITs as preparatory work for an upcoming MIPS eBPF JIT, from Johan Almbladh. 2) Add a batched interface for RX buffer allocation in AF_XDP buffer pool, with driver support for i40e and ice from Magnus Karlsson. 3) Add legacy uprobe support to libbpf to complement recently merged legacy kprobe support, from Andrii Nakryiko. 4) Add bpf_trace_vprintk() as variadic printk helper, from Dave Marchevsky. 5) Support saving the register state in verifier when spilling <8byte bounded scalar to the stack, from Martin Lau. 6) Add libbpf opt-in for stricter BPF program section name handling as part of libbpf 1.0 effort, from Andrii Nakryiko. 7) Add a document to help clarifying BPF licensing, from Alexei Starovoitov. 8) Fix skel_internal.h to propagate errno if the loader indicates an internal error, from Kumar Kartikeya Dwivedi. 9) Fix build warnings with -Wcast-function-type so that the option can later be enabled by default for the kernel, from Kees Cook. 10) Fix libbpf to ignore STT_SECTION symbols in legacy map definitions as it otherwise errors out when encountering them, from Toke Høiland-Jørgensen. 11) Teach libbpf to recognize specialized maps (such as for perf RB) and internally remove BTF type IDs when creating them, from Hengqi Chen. 12) Various fixes and improvements to BPF selftests. ==================== Link: https://lore.kernel.org/r/20211002001327.15169-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2-3/+6
drivers/net/phy/bcm7xxx.c d88fd1b546ff ("net: phy: bcm7xxx: Fixed indirect MMD operations") f68d08c437f9 ("net: phy: bcm7xxx: Add EPHY entry for 72165") net/sched/sch_api.c b193e15ac69d ("net: prevent user from passing illegal stab size") 69508d43334e ("net_sched: Use struct_size() and flex_array_size() helpers") Both cases trivial - adjacent code additions. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-30bpf: Fix integer overflow in prealloc_elems_and_freelist()Tatsuhiko Yasumatsu1-1/+2
In prealloc_elems_and_freelist(), the multiplication to calculate the size passed to bpf_map_area_alloc() could lead to an integer overflow. As a result, out-of-bounds write could occur in pcpu_freelist_populate() as reported by KASAN: [...] [ 16.968613] BUG: KASAN: slab-out-of-bounds in pcpu_freelist_populate+0xd9/0x100 [ 16.969408] Write of size 8 at addr ffff888104fc6ea0 by task crash/78 [ 16.970038] [ 16.970195] CPU: 0 PID: 78 Comm: crash Not tainted 5.15.0-rc2+ #1 [ 16.970878] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 [ 16.972026] Call Trace: [ 16.972306] dump_stack_lvl+0x34/0x44 [ 16.972687] print_address_description.constprop.0+0x21/0x140 [ 16.973297] ? pcpu_freelist_populate+0xd9/0x100 [ 16.973777] ? pcpu_freelist_populate+0xd9/0x100 [ 16.974257] kasan_report.cold+0x7f/0x11b [ 16.974681] ? pcpu_freelist_populate+0xd9/0x100 [ 16.975190] pcpu_freelist_populate+0xd9/0x100 [ 16.975669] stack_map_alloc+0x209/0x2a0 [ 16.976106] __sys_bpf+0xd83/0x2ce0 [...] The possibility of this overflow was originally discussed in [0], but was overlooked. Fix the integer overflow by changing elem_size to u64 from u32. [0] https://lore.kernel.org/bpf/728b238e-a481-eb50-98e9-b0f430ab01e7@gmail.com/ Fixes: 557c0c6e7df8 ("bpf: convert stackmap to pre-allocation") Signed-off-by: Tatsuhiko Yasumatsu <th.yasumatsu@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20210930135545.173698-1-th.yasumatsu@gmail.com
2021-09-28bpf: Replace callers of BPF_CAST_CALL with proper function typedefKees Cook3-11/+8
In order to keep ahead of cases in the kernel where Control Flow Integrity (CFI) may trip over function call casts, enabling -Wcast-function-type is helpful. To that end, BPF_CAST_CALL causes various warnings and is one of the last places in the kernel triggering this warning. For actual function calls, replace BPF_CAST_CALL() with a typedef, which captures the same details about the given function pointers. This change results in no object code difference. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org> Link: https://github.com/KSPP/linux/issues/20 Link: https://lore.kernel.org/lkml/CAEf4Bzb46=-J5Fxc3mMZ8JQPtK1uoE0q6+g6WPz53Cvx=CBEhw@mail.gmail.com Link: https://lore.kernel.org/bpf/20210928230946.4062144-3-keescook@chromium.org
2021-09-28bpf: Replace "want address" users of BPF_CAST_CALL with BPF_CALL_IMMKees Cook2-20/+12
In order to keep ahead of cases in the kernel where Control Flow Integrity (CFI) may trip over function call casts, enabling -Wcast-function-type is helpful. To that end, BPF_CAST_CALL causes various warnings and is one of the last places in the kernel triggering this warning. Most places using BPF_CAST_CALL actually just want a void * to perform math on. It's not actually performing a call, so just use a different helper to get the void *, by way of the new BPF_CALL_IMM() helper, which can clean up a common copy/paste idiom as well. This change results in no object code difference. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://github.com/KSPP/linux/issues/20 Link: https://lore.kernel.org/lkml/CAEf4Bzb46=-J5Fxc3mMZ8JQPtK1uoE0q6+g6WPz53Cvx=CBEhw@mail.gmail.com Link: https://lore.kernel.org/bpf/20210928230946.4062144-2-keescook@chromium.org
2021-09-28bpf: Exempt CAP_BPF from checks against bpf_jit_limitLorenz Bauer1-1/+1
When introducing CAP_BPF, bpf_jit_charge_modmem() was not changed to treat programs with CAP_BPF as privileged for the purpose of JIT memory allocation. This means that a program without CAP_BPF can block a program with CAP_BPF from loading a program. Fix this by checking bpf_capable() in bpf_jit_charge_modmem(). Fixes: 2c78ee898d8f ("bpf: Implement CAP_BPF") Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20210922111153.19843-1-lmb@cloudflare.com
2021-09-26bpf: Support <8-byte scalar spill and refillMartin KaFai Lau1-15/+52
The verifier currently does not save the reg state when spilling <8byte bounded scalar to the stack. The bpf program will be incorrectly rejected when this scalar is refilled to the reg and then used to offset into a packet header. The later patch has a simplified bpf prog from a real use case to demonstrate this case. The current work around is to reparse the packet again such that this offset scalar is close to where the packet data will be accessed to avoid the spill. Thus, the header is parsed twice. The llvm patch [1] will align the <8bytes spill to the 8-byte stack address. This can simplify the verifier support by avoiding to store multiple reg states for each 8 byte stack slot. This patch changes the verifier to save the reg state when spilling <8bytes scalar to the stack. This reg state saving is limited to spill aligned to the 8-byte stack address. The current refill logic has already called coerce_reg_to_size(), so coerce_reg_to_size() is not called on state->stack[spi].spilled_ptr during spill. When refilling in check_stack_read_fixed_off(), it checks the refill size is the same as the number of bytes marked with STACK_SPILL before restoring the reg state. When restoring the reg state to state->regs[dst_regno], it needs to avoid the state->regs[dst_regno].subreg_def being over written because it has been marked by the check_reg_arg() earlier [check_mem_access() is called after check_reg_arg() in do_check()]. Reordering check_mem_access() and check_reg_arg() will need a lot of changes in test_verifier's tests because of the difference in verifier's error message. Thus, the patch here is to save the state->regs[dst_regno].subreg_def first in check_stack_read_fixed_off(). There are cases that the verifier needs to scrub the spilled slot from STACK_SPILL to STACK_MISC. After this patch the spill is not always in 8 bytes now, so it can no longer assume the other 7 bytes are always marked as STACK_SPILL. In particular, the scrub needs to avoid marking an uninitialized byte from STACK_INVALID to STACK_MISC. Otherwise, the verifier will incorrectly accept bpf program reading uninitialized bytes from the stack. A new helper scrub_spilled_slot() is created for this purpose. [1]: https://reviews.llvm.org/D109073 Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210922004941.625398-1-kafai@fb.com
2021-09-26bpf: Check the other end of slot_type for STACK_SPILLMartin KaFai Lau1-11/+19
Every 8 bytes of the stack is tracked by a bpf_stack_state. Within each bpf_stack_state, there is a 'u8 slot_type[8]' to track the type of each byte. Verifier tests slot_type[0] == STACK_SPILL to decide if the spilled reg state is saved. Verifier currently only saves the reg state if the whole 8 bytes are spilled to the stack, so checking the slot_type[7] is the same as checking slot_type[0]. The later patch will allow verifier to save the bounded scalar reg also for <8 bytes spill. There is a llvm patch [1] to ensure the <8 bytes spill will be 8-byte aligned, so checking slot_type[7] instead of slot_type[0] is required. While at it, this patch refactors the slot_type[0] == STACK_SPILL test into a new function is_spilled_reg() and change the slot_type[0] check to slot_type[7] check in there also. [1] https://reviews.llvm.org/D109073 Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210922004934.624194-1-kafai@fb.com
2021-09-17bpf: Add bpf_trace_vprintk helperDave Marchevsky2-0/+7
This helper is meant to be "bpf_trace_printk, but with proper vararg support". Follow bpf_snprintf's example and take a u64 pseudo-vararg array. Write to /sys/kernel/debug/tracing/trace_pipe using the same mechanism as bpf_trace_printk. The functionality of this helper was requested in the libbpf issue tracker [0]. [0] Closes: https://github.com/libbpf/libbpf/issues/315 Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210917182911.2426606-4-davemarchevsky@fb.com
2021-09-17bpf: Merge printk and seq_printf VARARG max macrosDave Marchevsky1-3/+1
MAX_SNPRINTF_VARARGS and MAX_SEQ_PRINTF_VARARGS are used by bpf helpers bpf_snprintf and bpf_seq_printf to limit their varargs. Both call into bpf_bprintf_prepare for print formatting logic and have convenience macros in libbpf (BPF_SNPRINTF, BPF_SEQ_PRINTF) which use the same helper macros to convert varargs to a byte array. Changing shared functionality to support more varargs for either bpf helper would affect the other as well, so let's combine the _VARARGS macros to make this more obvious. Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210917182911.2426606-2-davemarchevsky@fb.com
2021-09-17Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski2-1/+130
Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-09-17 We've added 63 non-merge commits during the last 12 day(s) which contain a total of 65 files changed, 2653 insertions(+), 751 deletions(-). The main changes are: 1) Streamline internal BPF program sections handling and bpf_program__set_attach_target() in libbpf, from Andrii. 2) Add support for new btf kind BTF_KIND_TAG, from Yonghong. 3) Introduce bpf_get_branch_snapshot() to capture LBR, from Song. 4) IMUL optimization for x86-64 JIT, from Jie. 5) xsk selftest improvements, from Magnus. 6) Introduce legacy kprobe events support in libbpf, from Rafael. 7) Access hw timestamp through BPF's __sk_buff, from Vadim. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (63 commits) selftests/bpf: Fix a few compiler warnings libbpf: Constify all high-level program attach APIs libbpf: Schedule open_opts.attach_prog_fd deprecation since v0.7 selftests/bpf: Switch fexit_bpf2bpf selftest to set_attach_target() API libbpf: Allow skipping attach_func_name in bpf_program__set_attach_target() libbpf: Deprecated bpf_object_open_opts.relaxed_core_relocs selftests/bpf: Stop using relaxed_core_relocs which has no effect libbpf: Use pre-setup sec_def in libbpf_find_attach_btf_id() bpf: Update bpf_get_smp_processor_id() documentation libbpf: Add sphinx code documentation comments selftests/bpf: Skip btf_tag test if btf_tag attribute not supported docs/bpf: Add documentation for BTF_KIND_TAG selftests/bpf: Add a test with a bpf program with btf_tag attributes selftests/bpf: Test BTF_KIND_TAG for deduplication selftests/bpf: Add BTF_KIND_TAG unit tests selftests/bpf: Change NAME_NTH/IS_NAME_NTH for BTF_KIND_TAG format selftests/bpf: Test libbpf API function btf__add_tag() bpftool: Add support for BTF_KIND_TAG libbpf: Add support for BTF_KIND_TAG libbpf: Rename btf_{hash,equal}_int to btf_{hash,equal}_int_tag ... ==================== Link: https://lore.kernel.org/r/20210917173738.3397064-1-ast@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>