lib/audit.c provides a generic function for auditing system calls. This patch extends it for compat syscall support on bi-architectures (32/64-bit) by adding lib/compat_audit.c. What is required to support this feature are: * add asm/unistd32.h for compat system call names * select CONFIG_AUDIT_ARCH_COMPAT_GENERIC
Signed-off-by: AKASHI Takahiro takahiro.akashi@linaro.org --- include/linux/audit.h | 8 ++++++++ include/uapi/linux/audit.h | 6 ++++++ lib/Kconfig | 9 +++++++++ lib/Makefile | 1 + lib/audit.c | 15 +++++++++++++- lib/compat_audit.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++ 6 files changed, 88 insertions(+), 1 deletion(-) create mode 100644 lib/compat_audit.c
diff --git a/include/linux/audit.h b/include/linux/audit.h index aa865a9..85f0503 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -78,6 +78,14 @@ extern int is_audit_feature_set(int which); extern int __init audit_register_class(int class, unsigned *list); extern int audit_classify_syscall(int abi, unsigned syscall); extern int audit_classify_arch(int arch); +/* only for compat system calls */ +extern unsigned compat_write_class[]; +extern unsigned compat_read_class[]; +extern unsigned compat_dir_class[]; +extern unsigned compat_chattr_class[]; +extern unsigned compat_signal_class[]; + +extern int __weak audit_classify_compat_syscall(int abi, unsigned syscall);
/* audit_names->type values */ #define AUDIT_TYPE_UNKNOWN 0 /* we don't know yet */ diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h index 2d48fe1..624df43 100644 --- a/include/uapi/linux/audit.h +++ b/include/uapi/linux/audit.h @@ -361,6 +361,12 @@ enum { #define AUDIT_ARCH_SPARC64 (EM_SPARCV9|__AUDIT_ARCH_64BIT) #define AUDIT_ARCH_X86_64 (EM_X86_64|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE)
+#ifdef CONFIG_COMPAT +#define audit_is_compat(arch) (!((arch) & __AUDIT_ARCH_64BIT)) +#else +#define audit_is_compat(arch) false +#endif + #define AUDIT_PERM_EXEC 1 #define AUDIT_PERM_WRITE 2 #define AUDIT_PERM_READ 4 diff --git a/lib/Kconfig b/lib/Kconfig index 991c98b..1e80cb3 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -182,6 +182,15 @@ config AUDIT_GENERIC depends on AUDIT && !AUDIT_ARCH default y
+config AUDIT_ARCH_COMPAT_GENERIC + bool + default n + +config AUDIT_COMPAT_GENERIC + bool + depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT + default y + config RANDOM32_SELFTEST bool "PRNG perform self test on init" default n diff --git a/lib/Makefile b/lib/Makefile index 48140e3..0cd7b68 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -96,6 +96,7 @@ obj-$(CONFIG_TEXTSEARCH_BM) += ts_bm.o obj-$(CONFIG_TEXTSEARCH_FSM) += ts_fsm.o obj-$(CONFIG_SMP) += percpu_counter.o obj-$(CONFIG_AUDIT_GENERIC) += audit.o +obj-$(CONFIG_AUDIT_COMPAT_GENERIC) += compat_audit.o
obj-$(CONFIG_SWIOTLB) += swiotlb.o obj-$(CONFIG_IOMMU_HELPER) += iommu-helper.o diff --git a/lib/audit.c b/lib/audit.c index 76bbed4..1d726a2 100644 --- a/lib/audit.c +++ b/lib/audit.c @@ -30,11 +30,17 @@ static unsigned signal_class[] = {
int audit_classify_arch(int arch) { - return 0; + if (audit_is_compat(arch)) + return 1; + else + return 0; }
int audit_classify_syscall(int abi, unsigned syscall) { + if (audit_is_compat(abi)) + return audit_classify_compat_syscall(abi, syscall); + switch(syscall) { #ifdef __NR_open case __NR_open: @@ -57,6 +63,13 @@ int audit_classify_syscall(int abi, unsigned syscall)
static int __init audit_classes_init(void) { +#ifdef CONFIG_AUDIT_COMPAT_GENERIC + audit_register_class(AUDIT_CLASS_WRITE_32, compat_write_class); + audit_register_class(AUDIT_CLASS_READ_32, compat_read_class); + audit_register_class(AUDIT_CLASS_DIR_WRITE_32, compat_dir_class); + audit_register_class(AUDIT_CLASS_CHATTR_32, compat_chattr_class); + audit_register_class(AUDIT_CLASS_SIGNAL_32, compat_signal_class); +#endif audit_register_class(AUDIT_CLASS_WRITE, write_class); audit_register_class(AUDIT_CLASS_READ, read_class); audit_register_class(AUDIT_CLASS_DIR_WRITE, dir_class); diff --git a/lib/compat_audit.c b/lib/compat_audit.c new file mode 100644 index 0000000..873f75b --- /dev/null +++ b/lib/compat_audit.c @@ -0,0 +1,50 @@ +#include <linux/init.h> +#include <linux/types.h> +#include <asm/unistd32.h> + +unsigned compat_dir_class[] = { +#include <asm-generic/audit_dir_write.h> +~0U +}; + +unsigned compat_read_class[] = { +#include <asm-generic/audit_read.h> +~0U +}; + +unsigned compat_write_class[] = { +#include <asm-generic/audit_write.h> +~0U +}; + +unsigned compat_chattr_class[] = { +#include <asm-generic/audit_change_attr.h> +~0U +}; + +unsigned compat_signal_class[] = { +#include <asm-generic/audit_signal.h> +~0U +}; + +int audit_classify_compat_syscall(int abi, unsigned syscall) +{ + switch (syscall) { +#ifdef __NR_open + case __NR_open: + return 2; +#endif +#ifdef __NR_openat + case __NR_openat: + return 3; +#endif +#ifdef __NR_socketcall + case __NR_socketcall: + return 4; +#endif + case __NR_execve: + return 5; + default: + return 1; + } +}