A MIPS64 kernel may support ELF files for all 3 MIPS ABIs
(O32, N32, N64). Furthermore, the AUDIT_ARCH_MIPS{,EL}64 token
does not provide enough information about the ABI for the 64-bit
process. As a result of which, userland needs to use complex
seccomp filters to decide whether a syscall belongs to the o32 or n32
or n64 ABI. Therefore, a new arch token for MIPS64/n32 is added so it
can be used by seccomp to explicitely set syscall filters for this ABI.
Link: http://sourceforge.net/p/libseccomp/mailman/message/32239040/
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Eric Paris <eparis@xxxxxxxxxx>
Cc: Paul Moore <pmoore@xxxxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Signed-off-by: Markos Chandras <markos.chandras@xxxxxxxxxx>
---
Ralf, can we please have this in 3.15 (Assuming it's ACK'd)?
Thanks a lot!
---
arch/mips/include/asm/syscall.h | 2 ++
include/uapi/linux/audit.h | 12 ++++++++++++
2 files changed, 14 insertions(+)
diff --git a/arch/mips/include/asm/syscall.h b/arch/mips/include/asm/syscall.h
index c6e9cd2..17960fe 100644
--- a/arch/mips/include/asm/syscall.h
+++ b/arch/mips/include/asm/syscall.h
@@ -133,6 +133,8 @@ static inline int syscall_get_arch(void)
#ifdef CONFIG_64BIT
if (!test_thread_flag(TIF_32BIT_REGS))
arch |= __AUDIT_ARCH_64BIT;
+ if (test_thread_flag(TIF_32BIT_ADDR))
+ arch |= __AUDIT_ARCH_CONVENTION_MIPS64_N32;
#endif
#if defined(__LITTLE_ENDIAN)
arch |= __AUDIT_ARCH_LE;
diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h
index 11917f7..1b1efdd 100644
--- a/include/uapi/linux/audit.h
+++ b/include/uapi/linux/audit.h
@@ -331,9 +331,17 @@ enum {
#define AUDIT_FAIL_PRINTK 1
#define AUDIT_FAIL_PANIC 2
+/*
+ * These bits disambiguate different calling conventions that share an
+ * ELF machine type, bitness, and endianness
+ */
+#define __AUDIT_ARCH_CONVENTION_MASK 0x30000000
+#define __AUDIT_ARCH_CONVENTION_MIPS64_N32 0x20000000
+
/* distinguish syscall tables */
#define __AUDIT_ARCH_64BIT 0x80000000
#define __AUDIT_ARCH_LE 0x40000000
+
#define AUDIT_ARCH_ALPHA (EM_ALPHA|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE)
#define AUDIT_ARCH_ARM (EM_ARM|__AUDIT_ARCH_LE)
#define AUDIT_ARCH_ARMEB (EM_ARM)
@@ -346,7 +354,11 @@ enum {
#define AUDIT_ARCH_MIPS (EM_MIPS)
#define AUDIT_ARCH_MIPSEL (EM_MIPS|__AUDIT_ARCH_LE)
#define AUDIT_ARCH_MIPS64 (EM_MIPS|__AUDIT_ARCH_64BIT)
+#define AUDIT_ARCH_MIPS64N32 (EM_MIPS|__AUDIT_ARCH_64BIT|\
+ __AUDIT_ARCH_CONVENTION_MIPS64_N32)
#define AUDIT_ARCH_MIPSEL64 (EM_MIPS|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE)
+#define AUDIT_ARCH_MIPSEL64N32 (EM_MIPS|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE\
+ __AUDIT_ARCH_CONVENTION_MIPS64_N32)
#define AUDIT_ARCH_OPENRISC (EM_OPENRISC)
#define AUDIT_ARCH_PARISC (EM_PARISC)
#define AUDIT_ARCH_PARISC64 (EM_PARISC|__AUDIT_ARCH_64BIT)
--
1.9.2
