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authorLinus Torvalds <torvalds@linux-foundation.org>2008-07-23 20:39:21 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-23 20:39:21 -0700
commit338b9bb3adac0d2c5a1e180491d9b001d624c402 (patch)
tree1552739e19d1e2c41702a6cf1e4204e5f28a5722
parent7f9dce38378f0a4a298e885553d6bb7121376376 (diff)
parentaf0575bba0f46dd9054d46e0a88c57afad3bf4d2 (diff)
downloadlinux-338b9bb3adac0d2c5a1e180491d9b001d624c402.tar.gz
Merge branch 'x86/auditsc' of git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland
* 'x86/auditsc' of git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland: i386 syscall audit fast-path x86_64 ia32 syscall audit fast-path x86_64 syscall audit fast-path x86_64: remove bogus optimization in sysret_signal
-rw-r--r--arch/x86/ia32/ia32entry.S91
-rw-r--r--arch/x86/kernel/entry_32.S55
-rw-r--r--arch/x86/kernel/entry_64.S55
-rw-r--r--kernel/auditsc.c3
4 files changed, 192 insertions, 12 deletions
diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
index 23d146ce676b..021d71bc69b5 100644
--- a/arch/x86/ia32/ia32entry.S
+++ b/arch/x86/ia32/ia32entry.S
@@ -15,6 +15,16 @@
#include <asm/irqflags.h>
#include <linux/linkage.h>
+/* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */
+#include <linux/elf-em.h>
+#define AUDIT_ARCH_I386 (EM_386|__AUDIT_ARCH_LE)
+#define __AUDIT_ARCH_LE 0x40000000
+
+#ifndef CONFIG_AUDITSYSCALL
+#define sysexit_audit int_ret_from_sys_call
+#define sysretl_audit int_ret_from_sys_call
+#endif
+
#define IA32_NR_syscalls ((ia32_syscall_end - ia32_sys_call_table)/8)
.macro IA32_ARG_FIXUP noebp=0
@@ -148,13 +158,15 @@ ENTRY(ia32_sysenter_target)
ja ia32_badsys
sysenter_do_call:
IA32_ARG_FIXUP 1
+sysenter_dispatch:
call *ia32_sys_call_table(,%rax,8)
movq %rax,RAX-ARGOFFSET(%rsp)
GET_THREAD_INFO(%r10)
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
testl $_TIF_ALLWORK_MASK,TI_flags(%r10)
- jnz int_ret_from_sys_call
+ jnz sysexit_audit
+sysexit_from_sys_call:
andl $~TS_COMPAT,TI_status(%r10)
/* clear IF, that popfq doesn't enable interrupts early */
andl $~0x200,EFLAGS-R11(%rsp)
@@ -170,9 +182,63 @@ sysenter_do_call:
TRACE_IRQS_ON
ENABLE_INTERRUPTS_SYSEXIT32
-sysenter_tracesys:
+#ifdef CONFIG_AUDITSYSCALL
+ .macro auditsys_entry_common
+ movl %esi,%r9d /* 6th arg: 4th syscall arg */
+ movl %edx,%r8d /* 5th arg: 3rd syscall arg */
+ /* (already in %ecx) 4th arg: 2nd syscall arg */
+ movl %ebx,%edx /* 3rd arg: 1st syscall arg */
+ movl %eax,%esi /* 2nd arg: syscall number */
+ movl $AUDIT_ARCH_I386,%edi /* 1st arg: audit arch */
+ call audit_syscall_entry
+ movl RAX-ARGOFFSET(%rsp),%eax /* reload syscall number */
+ cmpl $(IA32_NR_syscalls-1),%eax
+ ja ia32_badsys
+ movl %ebx,%edi /* reload 1st syscall arg */
+ movl RCX-ARGOFFSET(%rsp),%esi /* reload 2nd syscall arg */
+ movl RDX-ARGOFFSET(%rsp),%edx /* reload 3rd syscall arg */
+ movl RSI-ARGOFFSET(%rsp),%ecx /* reload 4th syscall arg */
+ movl RDI-ARGOFFSET(%rsp),%r8d /* reload 5th syscall arg */
+ .endm
+
+ .macro auditsys_exit exit
+ testl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),TI_flags(%r10)
+ jnz int_ret_from_sys_call
+ TRACE_IRQS_ON
+ sti
+ movl %eax,%esi /* second arg, syscall return value */
+ cmpl $0,%eax /* is it < 0? */
+ setl %al /* 1 if so, 0 if not */
+ movzbl %al,%edi /* zero-extend that into %edi */
+ inc %edi /* first arg, 0->1(AUDITSC_SUCCESS), 1->2(AUDITSC_FAILURE) */
+ call audit_syscall_exit
+ GET_THREAD_INFO(%r10)
+ movl RAX-ARGOFFSET(%rsp),%eax /* reload syscall return value */
+ movl RBP-ARGOFFSET(%rsp),%ebp /* reload user register value */
+ movl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),%edi
+ cli
+ TRACE_IRQS_OFF
+ testl %edi,TI_flags(%r10)
+ jnz int_with_check
+ jmp \exit
+ .endm
+
+sysenter_auditsys:
CFI_RESTORE_STATE
+ auditsys_entry_common
+ movl %ebp,%r9d /* reload 6th syscall arg */
+ jmp sysenter_dispatch
+
+sysexit_audit:
+ auditsys_exit sysexit_from_sys_call
+#endif
+
+sysenter_tracesys:
xchgl %r9d,%ebp
+#ifdef CONFIG_AUDITSYSCALL
+ testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags(%r10)
+ jz sysenter_auditsys
+#endif
SAVE_REST
CLEAR_RREGS
movq %r9,R9(%rsp)
@@ -252,13 +318,15 @@ cstar_do_call:
cmpl $IA32_NR_syscalls-1,%eax
ja ia32_badsys
IA32_ARG_FIXUP 1
+cstar_dispatch:
call *ia32_sys_call_table(,%rax,8)
movq %rax,RAX-ARGOFFSET(%rsp)
GET_THREAD_INFO(%r10)
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
testl $_TIF_ALLWORK_MASK,TI_flags(%r10)
- jnz int_ret_from_sys_call
+ jnz sysretl_audit
+sysretl_from_sys_call:
andl $~TS_COMPAT,TI_status(%r10)
RESTORE_ARGS 1,-ARG_SKIP,1,1,1
movl RIP-ARGOFFSET(%rsp),%ecx
@@ -270,8 +338,23 @@ cstar_do_call:
CFI_RESTORE rsp
USERGS_SYSRET32
-cstar_tracesys:
+#ifdef CONFIG_AUDITSYSCALL
+cstar_auditsys:
CFI_RESTORE_STATE
+ movl %r9d,R9-ARGOFFSET(%rsp) /* register to be clobbered by call */
+ auditsys_entry_common
+ movl R9-ARGOFFSET(%rsp),%r9d /* reload 6th syscall arg */
+ jmp cstar_dispatch
+
+sysretl_audit:
+ auditsys_exit sysretl_from_sys_call
+#endif
+
+cstar_tracesys:
+#ifdef CONFIG_AUDITSYSCALL
+ testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags(%r10)
+ jz cstar_auditsys
+#endif
xchgl %r9d,%ebp
SAVE_REST
CLEAR_RREGS
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index cdfd94cc6b14..109792bc7cfa 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -54,6 +54,16 @@
#include <asm/ftrace.h>
#include <asm/irq_vectors.h>
+/* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */
+#include <linux/elf-em.h>
+#define AUDIT_ARCH_I386 (EM_386|__AUDIT_ARCH_LE)
+#define __AUDIT_ARCH_LE 0x40000000
+
+#ifndef CONFIG_AUDITSYSCALL
+#define sysenter_audit syscall_trace_entry
+#define sysexit_audit syscall_exit_work
+#endif
+
/*
* We use macros for low-level operations which need to be overridden
* for paravirtualization. The following will never clobber any registers:
@@ -333,7 +343,8 @@ sysenter_past_esp:
/* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */
testw $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%ebp)
- jnz syscall_trace_entry
+ jnz sysenter_audit
+sysenter_do_call:
cmpl $(nr_syscalls), %eax
jae syscall_badsys
call *sys_call_table(,%eax,4)
@@ -343,7 +354,8 @@ sysenter_past_esp:
TRACE_IRQS_OFF
movl TI_flags(%ebp), %ecx
testw $_TIF_ALLWORK_MASK, %cx
- jne syscall_exit_work
+ jne sysexit_audit
+sysenter_exit:
/* if something modifies registers it must also disable sysexit */
movl PT_EIP(%esp), %edx
movl PT_OLDESP(%esp), %ecx
@@ -351,6 +363,45 @@ sysenter_past_esp:
TRACE_IRQS_ON
1: mov PT_FS(%esp), %fs
ENABLE_INTERRUPTS_SYSEXIT
+
+#ifdef CONFIG_AUDITSYSCALL
+sysenter_audit:
+ testw $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags(%ebp)
+ jnz syscall_trace_entry
+ addl $4,%esp
+ CFI_ADJUST_CFA_OFFSET -4
+ /* %esi already in 8(%esp) 6th arg: 4th syscall arg */
+ /* %edx already in 4(%esp) 5th arg: 3rd syscall arg */
+ /* %ecx already in 0(%esp) 4th arg: 2nd syscall arg */
+ movl %ebx,%ecx /* 3rd arg: 1st syscall arg */
+ movl %eax,%edx /* 2nd arg: syscall number */
+ movl $AUDIT_ARCH_I386,%eax /* 1st arg: audit arch */
+ call audit_syscall_entry
+ pushl %ebx
+ CFI_ADJUST_CFA_OFFSET 4
+ movl PT_EAX(%esp),%eax /* reload syscall number */
+ jmp sysenter_do_call
+
+sysexit_audit:
+ testw $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT), %cx
+ jne syscall_exit_work
+ TRACE_IRQS_ON
+ ENABLE_INTERRUPTS(CLBR_ANY)
+ movl %eax,%edx /* second arg, syscall return value */
+ cmpl $0,%eax /* is it < 0? */
+ setl %al /* 1 if so, 0 if not */
+ movzbl %al,%eax /* zero-extend that */
+ inc %eax /* first arg, 0->1(AUDITSC_SUCCESS), 1->2(AUDITSC_FAILURE) */
+ call audit_syscall_exit
+ DISABLE_INTERRUPTS(CLBR_ANY)
+ TRACE_IRQS_OFF
+ movl TI_flags(%ebp), %ecx
+ testw $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT), %cx
+ jne syscall_exit_work
+ movl PT_EAX(%esp),%eax /* reload syscall return value */
+ jmp sysenter_exit
+#endif
+
CFI_ENDPROC
.pushsection .fixup,"ax"
2: movl $0,PT_FS(%esp)
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 8410e26f4183..89434d439605 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -53,6 +53,12 @@
#include <asm/paravirt.h>
#include <asm/ftrace.h>
+/* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */
+#include <linux/elf-em.h>
+#define AUDIT_ARCH_X86_64 (EM_X86_64|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE)
+#define __AUDIT_ARCH_64BIT 0x80000000
+#define __AUDIT_ARCH_LE 0x40000000
+
.code64
#ifdef CONFIG_FTRACE
@@ -351,6 +357,7 @@ ENTRY(system_call_after_swapgs)
GET_THREAD_INFO(%rcx)
testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%rcx)
jnz tracesys
+system_call_fastpath:
cmpq $__NR_syscall_max,%rax
ja badsys
movq %r10,%rcx
@@ -402,16 +409,16 @@ sysret_careful:
sysret_signal:
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
- testl $_TIF_DO_NOTIFY_MASK,%edx
- jz 1f
-
- /* Really a signal */
+#ifdef CONFIG_AUDITSYSCALL
+ bt $TIF_SYSCALL_AUDIT,%edx
+ jc sysret_audit
+#endif
/* edx: work flags (arg3) */
leaq do_notify_resume(%rip),%rax
leaq -ARGOFFSET(%rsp),%rdi # &pt_regs -> arg1
xorl %esi,%esi # oldset -> arg2
call ptregscall_common
-1: movl $_TIF_WORK_MASK,%edi
+ movl $_TIF_WORK_MASK,%edi
/* Use IRET because user could have changed frame. This
works because ptregscall_common has called FIXUP_TOP_OF_STACK. */
DISABLE_INTERRUPTS(CLBR_NONE)
@@ -422,8 +429,45 @@ badsys:
movq $-ENOSYS,RAX-ARGOFFSET(%rsp)
jmp ret_from_sys_call
+#ifdef CONFIG_AUDITSYSCALL
+ /*
+ * Fast path for syscall audit without full syscall trace.
+ * We just call audit_syscall_entry() directly, and then
+ * jump back to the normal fast path.
+ */
+auditsys:
+ movq %r10,%r9 /* 6th arg: 4th syscall arg */
+ movq %rdx,%r8 /* 5th arg: 3rd syscall arg */
+ movq %rsi,%rcx /* 4th arg: 2nd syscall arg */
+ movq %rdi,%rdx /* 3rd arg: 1st syscall arg */
+ movq %rax,%rsi /* 2nd arg: syscall number */
+ movl $AUDIT_ARCH_X86_64,%edi /* 1st arg: audit arch */
+ call audit_syscall_entry
+ LOAD_ARGS 0 /* reload call-clobbered registers */
+ jmp system_call_fastpath
+
+ /*
+ * Return fast path for syscall audit. Call audit_syscall_exit()
+ * directly and then jump back to the fast path with TIF_SYSCALL_AUDIT
+ * masked off.
+ */
+sysret_audit:
+ movq %rax,%rsi /* second arg, syscall return value */
+ cmpq $0,%rax /* is it < 0? */
+ setl %al /* 1 if so, 0 if not */
+ movzbl %al,%edi /* zero-extend that into %edi */
+ inc %edi /* first arg, 0->1(AUDITSC_SUCCESS), 1->2(AUDITSC_FAILURE) */
+ call audit_syscall_exit
+ movl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),%edi
+ jmp sysret_check
+#endif /* CONFIG_AUDITSYSCALL */
+
/* Do syscall tracing */
tracesys:
+#ifdef CONFIG_AUDITSYSCALL
+ testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags(%rcx)
+ jz auditsys
+#endif
SAVE_REST
movq $-ENOSYS,RAX(%rsp) /* ptrace can change this for a bad syscall */
FIXUP_TOP_OF_STACK %rdi
@@ -448,6 +492,7 @@ tracesys:
* Has correct top of stack, but partial stack frame.
*/
.globl int_ret_from_sys_call
+ .globl int_with_check
int_ret_from_sys_call:
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index c10e7aae04d7..4699950e65bd 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1476,7 +1476,8 @@ void audit_syscall_entry(int arch, int major,
struct audit_context *context = tsk->audit_context;
enum audit_state state;
- BUG_ON(!context);
+ if (unlikely(!context))
+ return;
/*
* This happens only on certain architectures that make system