/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. */ #include #include #include #include #include #include #include #include #include /* If kernel subsystem is allowing eBPF programs to call this function, * inside its own verifier_ops->get_func_proto() callback it should return * bpf_map_lookup_elem_proto, so that verifier can properly check the arguments * * Different map implementations will rely on rcu in map methods * lookup/update/delete, therefore eBPF programs must run under rcu lock * if program is allowed to access maps, so check rcu_read_lock_held in * all three functions. */ BPF_CALL_2(bpf_map_lookup_elem, struct bpf_map *, map, void *, key) { WARN_ON_ONCE(!rcu_read_lock_held()); return (unsigned long) map->ops->map_lookup_elem(map, key); } const struct bpf_func_proto bpf_map_lookup_elem_proto = { .func = bpf_map_lookup_elem, .gpl_only = false, .pkt_access = true, .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL, .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_PTR_TO_MAP_KEY, }; BPF_CALL_4(bpf_map_update_elem, struct bpf_map *, map, void *, key, void *, value, u64, flags) { WARN_ON_ONCE(!rcu_read_lock_held()); return map->ops->map_update_elem(map, key, value, flags); } const struct bpf_func_proto bpf_map_update_elem_proto = { .func = bpf_map_update_elem, .gpl_only = false, .pkt_access = true, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_PTR_TO_MAP_KEY, .arg3_type = ARG_PTR_TO_MAP_VALUE, .arg4_type = ARG_ANYTHING, }; BPF_CALL_2(bpf_map_delete_elem, struct bpf_map *, map, void *, key) { WARN_ON_ONCE(!rcu_read_lock_held()); return map->ops->map_delete_elem(map, key); } const struct bpf_func_proto bpf_map_delete_elem_proto = { .func = bpf_map_delete_elem, .gpl_only = false, .pkt_access = true, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_PTR_TO_MAP_KEY, }; const struct bpf_func_proto bpf_get_prandom_u32_proto = { .func = bpf_user_rnd_u32, .gpl_only = false, .ret_type = RET_INTEGER, }; BPF_CALL_0(bpf_get_smp_processor_id) { return smp_processor_id(); } const struct bpf_func_proto bpf_get_smp_processor_id_proto = { .func = bpf_get_smp_processor_id, .gpl_only = false, .ret_type = RET_INTEGER, }; BPF_CALL_0(bpf_get_numa_node_id) { return numa_node_id(); } const struct bpf_func_proto bpf_get_numa_node_id_proto = { .func = bpf_get_numa_node_id, .gpl_only = false, .ret_type = RET_INTEGER, }; BPF_CALL_0(bpf_ktime_get_ns) { /* NMI safe access to clock monotonic */ return ktime_get_mono_fast_ns(); } const struct bpf_func_proto bpf_ktime_get_ns_proto = { .func = bpf_ktime_get_ns, .gpl_only = true, .ret_type = RET_INTEGER, }; BPF_CALL_0(bpf_get_current_pid_tgid) { struct task_struct *task = current; if (unlikely(!task)) return -EINVAL; return (u64) task->tgid << 32 | task->pid; } const struct bpf_func_proto bpf_get_current_pid_tgid_proto = { .func = bpf_get_current_pid_tgid, .gpl_only = false, .ret_type = RET_INTEGER, }; BPF_CALL_0(bpf_get_current_uid_gid) { struct task_struct *task = current; kuid_t uid; kgid_t gid; if (unlikely(!task)) return -EINVAL; current_uid_gid(&uid, &gid); return (u64) from_kgid(&init_user_ns, gid) << 32 | from_kuid(&init_user_ns, uid); } const struct bpf_func_proto bpf_get_current_uid_gid_proto = { .func = bpf_get_current_uid_gid, .gpl_only = false, .ret_type = RET_INTEGER, }; BPF_CALL_2(bpf_get_current_comm, char *, buf, u32, size) { struct task_struct *task = current; if (unlikely(!task)) goto err_clear; strncpy(buf, task->comm, size); /* Verifier guarantees that size > 0. For task->comm exceeding * size, guarantee that buf is %NUL-terminated. Unconditionally * done here to save the size test. */ buf[size - 1] = 0; return 0; err_clear: memset(buf, 0, size); return -EINVAL; } const struct bpf_func_proto bpf_get_current_comm_proto = { .func = bpf_get_current_comm, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_RAW_STACK, .arg2_type = ARG_CONST_STACK_SIZE, }; Ingo Molnar <mingo@kernel.org>2017-02-01 21:17:49 +0100 commitc8f325a59cfc718d13a50fbc746ed9b415c25e92 (patch) treed53fbdac9d0781e39a13b2ac6b2bd258cf3b4140 /net/sched/Makefile parentbf29bddf0417a4783da3b24e8c9e017ac649326f (diff)
efi/fdt: Avoid FDT manipulation after ExitBootServices()
Some AArch64 UEFI implementations disable the MMU in ExitBootServices(), after which unaligned accesses to RAM are no longer supported. Commit: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") fixed an issue in the memory map handling of the stub FDT code, but inadvertently created an issue with such firmware, by moving some of the FDT manipulation to after the invocation of ExitBootServices(). Given that the stub's libfdt implementation uses the ordinary, accelerated string functions, which rely on hardware handling of unaligned accesses, manipulating the FDT with the MMU off may result in alignment faults. So fix the situation by moving the update_fdt_memmap() call into the callback function invoked by efi_exit_boot_services() right before it calls the ExitBootServices() UEFI service (which is arguably a better place for it anyway) Note that disabling the MMU in ExitBootServices() is not compliant with the UEFI spec, and carries great risk due to the fact that switching from cached to uncached memory accesses halfway through compiler generated code (i.e., involving a stack) can never be done in a way that is architecturally safe. Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Riku Voipio <riku.voipio@linaro.org> Cc: <stable@vger.kernel.org> Cc: mark.rutland@arm.com Cc: linux-efi@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: leif.lindholm@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'net/sched/Makefile')