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| author | Eduard Zingerman <eddyz87@gmail.com> | 2026-09-04 17:05:56 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2026-09-04 18:17:30 -0700 |
| commit | 506ada89629ec7059b96ecfb0dc7d33ece0103ca (patch) | |
| tree | 0b07297409b68d2333fb4f0eae7f3b072eb68d4c /arch/mips/kvm/hypcall.c | |
| download | linux-stable-506ada89629ec7059b96ecfb0dc7d33ece0103ca.tar.gz linux-stable-506ada89629ec7059b96ecfb0dc7d33ece0103ca.zip | |
bpf: mark a NULL kfunc argument precisegrafted
check_kfunc_arg() allows bpf_register_is_null() for nullable arguments
w/o marking the underlying scalar register precise. Hence a checkpoint
created on such a path would prune against arbitrary scalar value.
Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'arch/mips/kvm/hypcall.c')
| -rw-r--r-- | arch/mips/kvm/hypcall.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/arch/mips/kvm/hypcall.c b/arch/mips/kvm/hypcall.c new file mode 100644 index 000000000..830634351 --- /dev/null +++ b/arch/mips/kvm/hypcall.c @@ -0,0 +1,53 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * KVM/MIPS: Hypercall handling. + * + * Copyright (C) 2015 Imagination Technologies Ltd. + */ + +#include <linux/kernel.h> +#include <linux/kvm_host.h> +#include <linux/kvm_para.h> + +#define MAX_HYPCALL_ARGS 4 + +enum emulation_result kvm_mips_emul_hypcall(struct kvm_vcpu *vcpu, + union mips_instruction inst) +{ + unsigned int code = (inst.co_format.code >> 5) & 0x3ff; + + kvm_debug("[%#lx] HYPCALL %#03x\n", vcpu->arch.pc, code); + + switch (code) { + case 0: + return EMULATE_HYPERCALL; + default: + return EMULATE_FAIL; + }; +} + +static int kvm_mips_hypercall(struct kvm_vcpu *vcpu, unsigned long num, + const unsigned long *args, unsigned long *hret) +{ + /* Report unimplemented hypercall to guest */ + *hret = -KVM_ENOSYS; + return RESUME_GUEST; +} + +int kvm_mips_handle_hypcall(struct kvm_vcpu *vcpu) +{ + unsigned long num, args[MAX_HYPCALL_ARGS]; + + /* read hypcall number and arguments */ + num = vcpu->arch.gprs[2]; /* v0 */ + args[0] = vcpu->arch.gprs[4]; /* a0 */ + args[1] = vcpu->arch.gprs[5]; /* a1 */ + args[2] = vcpu->arch.gprs[6]; /* a2 */ + args[3] = vcpu->arch.gprs[7]; /* a3 */ + + return kvm_mips_hypercall(vcpu, num, + args, &vcpu->arch.gprs[2] /* v0 */); +} |