diff options
| -rw-r--r-- | pkg/seccomp/seccomp.go | 17 | ||||
| -rw-r--r-- | pkg/seccomp/seccomp_rules.go | 3 |
2 files changed, 20 insertions, 0 deletions
diff --git a/pkg/seccomp/seccomp.go b/pkg/seccomp/seccomp.go index c7503f2cc..fc36efa23 100644 --- a/pkg/seccomp/seccomp.go +++ b/pkg/seccomp/seccomp.go @@ -199,6 +199,10 @@ func ruleViolationLabel(ruleSetIdx int, sysno uintptr, idx int) string { return fmt.Sprintf("ruleViolation_%v_%v_%v", ruleSetIdx, sysno, idx) } +func ruleLabel(ruleSetIdx int, sysno uintptr, idx int, name string) string { + return fmt.Sprintf("rule_%v_%v_%v_%v", ruleSetIdx, sysno, idx, name) +} + func checkArgsLabel(sysno uintptr) string { return fmt.Sprintf("checkArgs_%v", sysno) } @@ -223,6 +227,19 @@ func addSyscallArgsCheck(p *bpf.ProgramBuilder, rules []Rule, action linux.BPFAc p.AddStmt(bpf.Ld|bpf.Abs|bpf.W, seccompDataOffsetArgHigh(i)) p.AddJumpFalseLabel(bpf.Jmp|bpf.Jeq|bpf.K, high, 0, ruleViolationLabel(ruleSetIdx, sysno, ruleidx)) labelled = true + case GreaterThan: + labelGood := fmt.Sprintf("gt%v", i) + high, low := uint32(a>>32), uint32(a) + // assert arg_high < high + p.AddStmt(bpf.Ld|bpf.Abs|bpf.W, seccompDataOffsetArgHigh(i)) + p.AddJumpFalseLabel(bpf.Jmp|bpf.Jge|bpf.K, high, 0, ruleViolationLabel(ruleSetIdx, sysno, ruleidx)) + // arg_high > high + p.AddJumpFalseLabel(bpf.Jmp|bpf.Jeq|bpf.K, high, 0, ruleLabel(ruleSetIdx, sysno, ruleidx, labelGood)) + // arg_low < low + p.AddStmt(bpf.Ld|bpf.Abs|bpf.W, seccompDataOffsetArgLow(i)) + p.AddJumpFalseLabel(bpf.Jmp|bpf.Jgt|bpf.K, low, 0, ruleViolationLabel(ruleSetIdx, sysno, ruleidx)) + p.AddLabel(ruleLabel(ruleSetIdx, sysno, ruleidx, labelGood)) + labelled = true default: return fmt.Errorf("unknown syscall rule type: %v", reflect.TypeOf(a)) } diff --git a/pkg/seccomp/seccomp_rules.go b/pkg/seccomp/seccomp_rules.go index 29eec8db1..84c841d7f 100644 --- a/pkg/seccomp/seccomp_rules.go +++ b/pkg/seccomp/seccomp_rules.go @@ -49,6 +49,9 @@ func (a AllowAny) String() (s string) { // AllowValue specifies a value that needs to be strictly matched. type AllowValue uintptr +// GreaterThan specifies a value that needs to be strictly smaller. +type GreaterThan uintptr + func (a AllowValue) String() (s string) { return fmt.Sprintf("%#x ", uintptr(a)) } |