[PATCH v4 2/3] audit: add support for the openat2 syscall

[Richard Guy Briggs <rgb@xxxxxxxxxx>]

The openat2(2) syscall was added in kernel v5.6 with commit fddb5d430ad9
("open: introduce openat2(2) syscall")

Add the openat2(2) syscall to the audit syscall classifier.

Link: https://github.com/linux-audit/audit-kernel/issues/67
Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
Link: https://lore.kernel.org/r/f5f1a4d8699613f8c02ce762807228c841c2e26f.1621363275.git.rgb@xxxxxxxxxx
---
 arch/alpha/kernel/audit.c           | 2 ++
 arch/ia64/kernel/audit.c            | 2 ++
 arch/parisc/kernel/audit.c          | 2 ++
 arch/parisc/kernel/compat_audit.c   | 2 ++
 arch/powerpc/kernel/audit.c         | 2 ++
 arch/powerpc/kernel/compat_audit.c  | 2 ++
 arch/s390/kernel/audit.c            | 2 ++
 arch/s390/kernel/compat_audit.c     | 2 ++
 arch/sparc/kernel/audit.c           | 2 ++
 arch/sparc/kernel/compat_audit.c    | 2 ++
 arch/x86/ia32/audit.c               | 2 ++
 arch/x86/kernel/audit_64.c          | 2 ++
 include/linux/auditsc_classmacros.h | 1 +
 kernel/auditsc.c                    | 3 +++
 lib/audit.c                         | 4 ++++
 lib/compat_audit.c                  | 4 ++++
 16 files changed, 36 insertions(+)

diff --git a/arch/alpha/kernel/audit.c b/arch/alpha/kernel/audit.c
index 81cbd804e375..3ab04709784a 100644
--- a/arch/alpha/kernel/audit.c
+++ b/arch/alpha/kernel/audit.c
@@ -42,6 +42,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
 		return AUDITSC_OPENAT;
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_NATIVE;
 	}
diff --git a/arch/ia64/kernel/audit.c b/arch/ia64/kernel/audit.c
index dba6a74c9ab3..ec61f20ca61f 100644
--- a/arch/ia64/kernel/audit.c
+++ b/arch/ia64/kernel/audit.c
@@ -43,6 +43,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
 		return AUDITSC_OPENAT;
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_NATIVE;
 	}
diff --git a/arch/parisc/kernel/audit.c b/arch/parisc/kernel/audit.c
index 14244e83db75..f420b5552140 100644
--- a/arch/parisc/kernel/audit.c
+++ b/arch/parisc/kernel/audit.c
@@ -52,6 +52,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
 		return AUDITSC_OPENAT;
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_NATIVE;
 	}
diff --git a/arch/parisc/kernel/compat_audit.c b/arch/parisc/kernel/compat_audit.c
index 1d6347d37d92..3ec490c28656 100644
--- a/arch/parisc/kernel/compat_audit.c
+++ b/arch/parisc/kernel/compat_audit.c
@@ -36,6 +36,8 @@ int parisc32_classify_syscall(unsigned syscall)
 		return AUDITSC_OPENAT;
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_COMPAT;
 	}
diff --git a/arch/powerpc/kernel/audit.c b/arch/powerpc/kernel/audit.c
index 6eb18ef77dff..1bcfca5fdf67 100644
--- a/arch/powerpc/kernel/audit.c
+++ b/arch/powerpc/kernel/audit.c
@@ -54,6 +54,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
 		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_NATIVE;
 	}
diff --git a/arch/powerpc/kernel/compat_audit.c b/arch/powerpc/kernel/compat_audit.c
index b1dc2d1c4bad..251abf79d536 100644
--- a/arch/powerpc/kernel/compat_audit.c
+++ b/arch/powerpc/kernel/compat_audit.c
@@ -39,6 +39,8 @@ int ppc32_classify_syscall(unsigned syscall)
 		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_COMPAT;
 	}
diff --git a/arch/s390/kernel/audit.c b/arch/s390/kernel/audit.c
index 7e331e1831d4..02051a596b87 100644
--- a/arch/s390/kernel/audit.c
+++ b/arch/s390/kernel/audit.c
@@ -54,6 +54,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
 		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_NATIVE;
 	}
diff --git a/arch/s390/kernel/compat_audit.c b/arch/s390/kernel/compat_audit.c
index fc3d1c7ad21c..4b3d463e7d97 100644
--- a/arch/s390/kernel/compat_audit.c
+++ b/arch/s390/kernel/compat_audit.c
@@ -40,6 +40,8 @@ int s390_classify_syscall(unsigned syscall)
 		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_COMPAT;
 	}
diff --git a/arch/sparc/kernel/audit.c b/arch/sparc/kernel/audit.c
index 50fab35bdaba..b092274eca79 100644
--- a/arch/sparc/kernel/audit.c
+++ b/arch/sparc/kernel/audit.c
@@ -55,6 +55,8 @@ int audit_classify_syscall(int abi, unsigned int syscall)
 		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_NATIVE;
 	}
diff --git a/arch/sparc/kernel/compat_audit.c b/arch/sparc/kernel/compat_audit.c
index 1c1b6d075421..2a3f71206fc5 100644
--- a/arch/sparc/kernel/compat_audit.c
+++ b/arch/sparc/kernel/compat_audit.c
@@ -40,6 +40,8 @@ int sparc32_classify_syscall(unsigned int syscall)
 		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_COMPAT;
 	}
diff --git a/arch/x86/ia32/audit.c b/arch/x86/ia32/audit.c
index eedc37a1ee13..efc7d832fefb 100644
--- a/arch/x86/ia32/audit.c
+++ b/arch/x86/ia32/audit.c
@@ -40,6 +40,8 @@ int ia32_classify_syscall(unsigned syscall)
 	case __NR_execve:
 	case __NR_execveat:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_COMPAT;
 	}
diff --git a/arch/x86/kernel/audit_64.c b/arch/x86/kernel/audit_64.c
index 2a6cc9c9c881..44c3601cfdc4 100644
--- a/arch/x86/kernel/audit_64.c
+++ b/arch/x86/kernel/audit_64.c
@@ -53,6 +53,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
 	case __NR_execve:
 	case __NR_execveat:
 		return AUDITSC_EXECVE;
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
 	default:
 		return AUDITSC_NATIVE;
 	}
diff --git a/include/linux/auditsc_classmacros.h b/include/linux/auditsc_classmacros.h
index 18757d270961..dc8e72536dbd 100644
--- a/include/linux/auditsc_classmacros.h
+++ b/include/linux/auditsc_classmacros.h
@@ -16,6 +16,7 @@ enum auditsc_class_t {
 	AUDITSC_OPENAT,
 	AUDITSC_SOCKETCALL,
 	AUDITSC_EXECVE,
+	AUDITSC_OPENAT2,
 
 	AUDITSC_NVALS /* count */
 };
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index d775ea16505b..3f59ab209dfd 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -76,6 +76,7 @@
 #include <linux/fsnotify_backend.h>
 #include <uapi/linux/limits.h>
 #include <uapi/linux/netfilter/nf_tables.h>
+#include <uapi/linux/openat2.h>
 
 #include "audit.h"
 
@@ -196,6 +197,8 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
 		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
 	case AUDITSC_EXECVE:
 		return mask & AUDIT_PERM_EXEC;
+	case AUDITSC_OPENAT2:
+		return mask & ACC_MODE((u32)((struct open_how *)ctx->argv[2])->flags);
 	default:
 		return 0;
 	}
diff --git a/lib/audit.c b/lib/audit.c
index 3ec1a94d8d64..738bda22dd39 100644
--- a/lib/audit.c
+++ b/lib/audit.c
@@ -60,6 +60,10 @@ int audit_classify_syscall(int abi, unsigned syscall)
 #endif
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+#ifdef __NR_openat2
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
+#endif
 	default:
 		return AUDITSC_NATIVE;
 	}
diff --git a/lib/compat_audit.c b/lib/compat_audit.c
index a38b282d353f..e2a0f914d8b6 100644
--- a/lib/compat_audit.c
+++ b/lib/compat_audit.c
@@ -46,6 +46,10 @@ int audit_classify_compat_syscall(int abi, unsigned syscall)
 #endif
 	case __NR_execve:
 		return AUDITSC_EXECVE;
+#ifdef __NR_openat2
+	case __NR_openat2:
+		return AUDITSC_OPENAT2;
+#endif
 	default:
 		return AUDITSC_COMPAT;
 	}
-- 
2.27.0