[patch] prepare kprobes code for x86 unification
From: Arjan van de Ven
Date: Wed Oct 24 2007 - 18:04:28 EST
From: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Subject: prepare kprobes code for x86 unification
This patch is a first step towards unification of the kprobes
infrastructure between 32 and 64 bit x86; the patch is mostly
about removing spurious whitespace changes and about adding
harmless includes and the like to make the 32/64 files more
identical.
Signed-off-by: Arjan van de Ven
---
arch/x86/kernel/kprobes_32.c | 179 +++++++++++++++++++++++++++++--------------
arch/x86/kernel/kprobes_64.c | 176 ++++++++++++++++++++++++++----------------
arch/x86/mm/fault_32.c | 1
arch/x86/mm/fault_64.c | 1
include/asm-x86/kprobes_32.h | 18 ++--
include/asm-x86/kprobes_64.h | 28 ++++--
6 files changed, 258 insertions(+), 145 deletions(-)
Index: linux-2.6.24-rc1/arch/x86/kernel/kprobes_32.c
===================================================================
--- linux-2.6.24-rc1.orig/arch/x86/kernel/kprobes_32.c
+++ linux-2.6.24-rc1/arch/x86/kernel/kprobes_32.c
@@ -29,10 +29,15 @@
#include <linux/kprobes.h>
#include <linux/ptrace.h>
+#include <linux/string.h>
+#include <linux/slab.h>
#include <linux/preempt.h>
+#include <linux/module.h>
#include <linux/kdebug.h>
+
#include <asm/cacheflush.h>
#include <asm/desc.h>
+#include <asm/pgtable.h>
#include <asm/uaccess.h>
#include <asm/alternative.h>
@@ -41,30 +46,6 @@ void jprobe_return_end(void);
DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
-struct kretprobe_blackpoint kretprobe_blacklist[] = {
- {"__switch_to", }, /* This function switches only current task, but
- doesn't switch kernel stack.*/
- {NULL, NULL} /* Terminator */
-};
-const int kretprobe_blacklist_size = ARRAY_SIZE(kretprobe_blacklist);
-
-/* insert a jmp code */
-static __always_inline void set_jmp_op(void *from, void *to)
-{
- struct __arch_jmp_op {
- char op;
- long raddr;
- } __attribute__((packed)) *jop;
- jop = (struct __arch_jmp_op *)from;
- jop->raddr = (long)(to) - ((long)(from) + 5);
- jop->op = RELATIVEJUMP_INSTRUCTION;
-}
-
-/*
- * returns non-zero if opcodes can be boosted.
- */
-static __always_inline int can_boost(kprobe_opcode_t *opcodes)
-{
#define W(row,b0,b1,b2,b3,b4,b5,b6,b7,b8,b9,ba,bb,bc,bd,be,bf) \
(((b0##UL << 0x0)|(b1##UL << 0x1)|(b2##UL << 0x2)|(b3##UL << 0x3) | \
(b4##UL << 0x4)|(b5##UL << 0x5)|(b6##UL << 0x6)|(b7##UL << 0x7) | \
@@ -75,7 +56,7 @@ static __always_inline int can_boost(kpr
* Undefined/reserved opcodes, conditional jump, Opcode Extension
* Groups, and some special opcodes can not be boost.
*/
- static const unsigned long twobyte_is_boostable[256 / 32] = {
+static const unsigned long twobyte_is_boostable[256 / 32] = {
/* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
/* ------------------------------- */
W(0x00, 0,0,1,1,0,0,1,0,1,1,0,0,0,0,0,0)| /* 00 */
@@ -96,8 +77,85 @@ static __always_inline int can_boost(kpr
W(0xf0, 0,1,1,1,0,1,0,0,1,1,1,0,1,1,1,0) /* f0 */
/* ------------------------------- */
/* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
- };
+};
#undef W
+
+#define W(row,b0,b1,b2,b3,b4,b5,b6,b7,b8,b9,ba,bb,bc,bd,be,bf) \
+ (((b0##UL << 0x0)|(b1##UL << 0x1)|(b2##UL << 0x2)|(b3##UL << 0x3) | \
+ (b4##UL << 0x4)|(b5##UL << 0x5)|(b6##UL << 0x6)|(b7##UL << 0x7) | \
+ (b8##UL << 0x8)|(b9##UL << 0x9)|(ba##UL << 0xa)|(bb##UL << 0xb) | \
+ (bc##UL << 0xc)|(bd##UL << 0xd)|(be##UL << 0xe)|(bf##UL << 0xf)) \
+ << (row % 64))
+static const u64 onebyte_has_modrm[256 / 64] = {
+ /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
+ /* ------------------------------- */
+ W(0x00, 1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0)| /* 00 */
+ W(0x10, 1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0)| /* 10 */
+ W(0x20, 1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0)| /* 20 */
+ W(0x30, 1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0), /* 30 */
+ W(0x40, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)| /* 40 */
+ W(0x50, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)| /* 50 */
+ W(0x60, 0,0,1,1,0,0,0,0,0,1,0,1,0,0,0,0)| /* 60 */
+ W(0x70, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0), /* 70 */
+ W(0x80, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 80 */
+ W(0x90, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)| /* 90 */
+ W(0xa0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)| /* a0 */
+ W(0xb0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0), /* b0 */
+ W(0xc0, 1,1,0,0,1,1,1,1,0,0,0,0,0,0,0,0)| /* c0 */
+ W(0xd0, 1,1,1,1,0,0,0,0,1,1,1,1,1,1,1,1)| /* d0 */
+ W(0xe0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)| /* e0 */
+ W(0xf0, 0,0,0,0,0,0,1,1,0,0,0,0,0,0,1,1) /* f0 */
+ /* ------------------------------- */
+ /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
+};
+static const u64 twobyte_has_modrm[256 / 64] = {
+ /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
+ /* ------------------------------- */
+ W(0x00, 1,1,1,1,0,0,0,0,0,0,0,0,0,1,0,1)| /* 0f */
+ W(0x10, 1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,0)| /* 1f */
+ W(0x20, 1,1,1,1,1,0,1,0,1,1,1,1,1,1,1,1)| /* 2f */
+ W(0x30, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0), /* 3f */
+ W(0x40, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 4f */
+ W(0x50, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 5f */
+ W(0x60, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 6f */
+ W(0x70, 1,1,1,1,1,1,1,0,0,0,0,0,1,1,1,1), /* 7f */
+ W(0x80, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)| /* 8f */
+ W(0x90, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 9f */
+ W(0xa0, 0,0,0,1,1,1,1,1,0,0,0,1,1,1,1,1)| /* af */
+ W(0xb0, 1,1,1,1,1,1,1,1,0,0,1,1,1,1,1,1), /* bf */
+ W(0xc0, 1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0)| /* cf */
+ W(0xd0, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* df */
+ W(0xe0, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* ef */
+ W(0xf0, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0) /* ff */
+ /* ------------------------------- */
+ /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
+};
+#undef W
+
+struct kretprobe_blackpoint kretprobe_blacklist[] = {
+ {"__switch_to", }, /* This function switches only current task, but
+ doesn't switch kernel stack.*/
+ {NULL, NULL} /* Terminator */
+};
+const int kretprobe_blacklist_size = ARRAY_SIZE(kretprobe_blacklist);
+
+/* insert a jmp code */
+static __always_inline void set_jmp_op(void *from, void *to)
+{
+ struct __arch_jmp_op {
+ char op;
+ long raddr;
+ } __attribute__((packed)) *jop;
+ jop = (struct __arch_jmp_op *)from;
+ jop->raddr = (long)(to) - ((long)(from) + 5);
+ jop->op = RELATIVEJUMP_INSTRUCTION;
+}
+
+/*
+ * returns non-zero if opcodes can be boosted.
+ */
+static __always_inline int can_boost(kprobe_opcode_t *opcodes)
+{
kprobe_opcode_t opcode;
kprobe_opcode_t *orig_opcodes = opcodes;
retry:
@@ -145,9 +203,9 @@ retry:
/*
* returns non-zero if opcode modifies the interrupt flag.
*/
-static int __kprobes is_IF_modifier(kprobe_opcode_t opcode)
+static __always_inline int is_IF_modifier(kprobe_opcode_t *insn)
{
- switch (opcode) {
+ switch (*insn) {
case 0xfa: /* cli */
case 0xfb: /* sti */
case 0xcf: /* iret/iretd */
@@ -157,20 +215,24 @@ static int __kprobes is_IF_modifier(kpro
return 0;
}
-int __kprobes arch_prepare_kprobe(struct kprobe *p)
+static void __kprobes arch_copy_kprobe(struct kprobe *p)
{
- /* insn: must be on special executable page on i386. */
- p->ainsn.insn = get_insn_slot();
- if (!p->ainsn.insn)
- return -ENOMEM;
-
memcpy(p->ainsn.insn, p->addr, MAX_INSN_SIZE * sizeof(kprobe_opcode_t));
- p->opcode = *p->addr;
if (can_boost(p->addr)) {
p->ainsn.boostable = 0;
} else {
p->ainsn.boostable = -1;
}
+ p->opcode = *p->addr;
+}
+
+int __kprobes arch_prepare_kprobe(struct kprobe *p)
+{
+ /* insn: must be on special executable page on x86. */
+ p->ainsn.insn = get_insn_slot();
+ if (!p->ainsn.insn)
+ return -ENOMEM;
+ arch_copy_kprobe(p);
return 0;
}
@@ -195,26 +257,26 @@ static void __kprobes save_previous_kpro
{
kcb->prev_kprobe.kp = kprobe_running();
kcb->prev_kprobe.status = kcb->kprobe_status;
- kcb->prev_kprobe.old_eflags = kcb->kprobe_old_eflags;
- kcb->prev_kprobe.saved_eflags = kcb->kprobe_saved_eflags;
+ kcb->prev_kprobe.old_flags = kcb->kprobe_old_flags;
+ kcb->prev_kprobe.saved_flags = kcb->kprobe_saved_flags;
}
static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb)
{
__get_cpu_var(current_kprobe) = kcb->prev_kprobe.kp;
kcb->kprobe_status = kcb->prev_kprobe.status;
- kcb->kprobe_old_eflags = kcb->prev_kprobe.old_eflags;
- kcb->kprobe_saved_eflags = kcb->prev_kprobe.saved_eflags;
+ kcb->kprobe_old_flags = kcb->prev_kprobe.old_flags;
+ kcb->kprobe_saved_flags = kcb->prev_kprobe.saved_flags;
}
static void __kprobes set_current_kprobe(struct kprobe *p, struct pt_regs *regs,
struct kprobe_ctlblk *kcb)
{
__get_cpu_var(current_kprobe) = p;
- kcb->kprobe_saved_eflags = kcb->kprobe_old_eflags
+ kcb->kprobe_saved_flags = kcb->kprobe_old_flags
= (regs->eflags & (TF_MASK | IF_MASK));
- if (is_IF_modifier(p->opcode))
- kcb->kprobe_saved_eflags &= ~IF_MASK;
+ if (is_IF_modifier(p->ainsn.insn))
+ kcb->kprobe_saved_flags &= ~IF_MASK;
}
static void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs)
@@ -267,7 +329,7 @@ static int __kprobes kprobe_handler(stru
if (kcb->kprobe_status == KPROBE_HIT_SS &&
*p->ainsn.insn == BREAKPOINT_INSTRUCTION) {
regs->eflags &= ~TF_MASK;
- regs->eflags |= kcb->kprobe_saved_eflags;
+ regs->eflags |= kcb->kprobe_saved_flags;
goto no_kprobe;
}
/* We have reentered the kprobe_handler(), since
@@ -488,7 +550,7 @@ static void __kprobes resume_execution(s
switch (p->ainsn.insn[0]) {
case 0x9c: /* pushfl */
*tos &= ~(TF_MASK | IF_MASK);
- *tos |= kcb->kprobe_old_eflags;
+ *tos |= kcb->kprobe_old_flags;
break;
case 0xc2: /* iret/ret/lret */
case 0xc3:
@@ -563,7 +625,7 @@ static int __kprobes post_kprobe_handler
}
resume_execution(cur, regs, kcb);
- regs->eflags |= kcb->kprobe_saved_eflags;
+ regs->eflags |= kcb->kprobe_saved_flags;
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
if (raw_irqs_disabled_flags(regs->eflags))
trace_hardirqs_off();
@@ -571,7 +633,7 @@ static int __kprobes post_kprobe_handler
trace_hardirqs_on();
#endif
- /*Restore back the original saved kprobes variables and continue. */
+ /* Restore back the original saved kprobes variables and continue. */
if (kcb->kprobe_status == KPROBE_REENTER) {
restore_previous_kprobe(kcb);
goto out;
@@ -607,7 +669,7 @@ int __kprobes kprobe_fault_handler(struc
* normal page fault.
*/
regs->eip = (unsigned long)cur->addr;
- regs->eflags |= kcb->kprobe_old_eflags;
+ regs->eflags |= kcb->kprobe_old_flags;
if (kcb->kprobe_status == KPROBE_REENTER)
restore_previous_kprobe(kcb);
else
@@ -652,7 +714,7 @@ int __kprobes kprobe_fault_handler(struc
}
/*
- * Wrapper routine to for handling exceptions.
+ * Wrapper routine for handling exceptions.
*/
int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data)
@@ -693,11 +755,11 @@ int __kprobes setjmp_pre_handler(struct
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
kcb->jprobe_saved_regs = *regs;
- kcb->jprobe_saved_esp = ®s->esp;
- addr = (unsigned long)(kcb->jprobe_saved_esp);
+ kcb->jprobe_saved_sp = ®s->esp;
+ addr = (unsigned long)(kcb->jprobe_saved_sp);
/*
- * TBD: As Linus pointed out, gcc assumes that the callee
+ * As Linus pointed out, gcc assumes that the callee
* owns the argument space and could overwrite it, e.g.
* tailcall optimization. So, to be absolutely safe
* we also save and restore enough stack bytes to cover
@@ -720,23 +782,23 @@ void __kprobes jprobe_return(void)
" .globl jprobe_return_end \n"
" jprobe_return_end: \n"
" nop \n"::"b"
- (kcb->jprobe_saved_esp):"memory");
+ (kcb->jprobe_saved_sp):"memory");
}
int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
{
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
u8 *addr = (u8 *) (regs->eip - 1);
- unsigned long stack_addr = (unsigned long)(kcb->jprobe_saved_esp);
+ unsigned long stack_addr = (unsigned long)(kcb->jprobe_saved_sp);
struct jprobe *jp = container_of(p, struct jprobe, kp);
if ((addr > (u8 *) jprobe_return) && (addr < (u8 *) jprobe_return_end)) {
- if (®s->esp != kcb->jprobe_saved_esp) {
+ if (®s->esp != kcb->jprobe_saved_sp) {
struct pt_regs *saved_regs =
- container_of(kcb->jprobe_saved_esp,
+ container_of(kcb->jprobe_saved_sp,
struct pt_regs, esp);
printk("current esp %p does not match saved esp %p\n",
- ®s->esp, kcb->jprobe_saved_esp);
+ ®s->esp, kcb->jprobe_saved_sp);
printk("Saved registers for jprobe %p\n", jp);
show_registers(saved_regs);
printk("Current registers\n");
@@ -752,12 +814,13 @@ int __kprobes longjmp_break_handler(stru
return 0;
}
-int __kprobes arch_trampoline_kprobe(struct kprobe *p)
+int __init arch_init_kprobes(void)
{
return 0;
}
-int __init arch_init_kprobes(void)
+int __kprobes arch_trampoline_kprobe(struct kprobe *p)
{
return 0;
}
+
Index: linux-2.6.24-rc1/arch/x86/kernel/kprobes_64.c
===================================================================
--- linux-2.6.24-rc1.orig/arch/x86/kernel/kprobes_64.c
+++ linux-2.6.24-rc1/arch/x86/kernel/kprobes_64.c
@@ -38,66 +38,58 @@
#include <linux/module.h>
#include <linux/kdebug.h>
+#include <asm/cacheflush.h>
+#include <asm/desc.h>
#include <asm/pgtable.h>
#include <asm/uaccess.h>
#include <asm/alternative.h>
void jprobe_return_end(void);
-static void __kprobes arch_copy_kprobe(struct kprobe *p);
DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
-struct kretprobe_blackpoint kretprobe_blacklist[] = {
- {"__switch_to", }, /* This function switches only current task, but
- doesn't switch kernel stack.*/
- {NULL, NULL} /* Terminator */
+#define W(row,b0,b1,b2,b3,b4,b5,b6,b7,b8,b9,ba,bb,bc,bd,be,bf) \
+ (((b0##UL << 0x0)|(b1##UL << 0x1)|(b2##UL << 0x2)|(b3##UL << 0x3) | \
+ (b4##UL << 0x4)|(b5##UL << 0x5)|(b6##UL << 0x6)|(b7##UL << 0x7) | \
+ (b8##UL << 0x8)|(b9##UL << 0x9)|(ba##UL << 0xa)|(bb##UL << 0xb) | \
+ (bc##UL << 0xc)|(bd##UL << 0xd)|(be##UL << 0xe)|(bf##UL << 0xf)) \
+ << (row % 32))
+ /*
+ * Undefined/reserved opcodes, conditional jump, Opcode Extension
+ * Groups, and some special opcodes can not be boost.
+ */
+static const unsigned long twobyte_is_boostable[256 / 32] = {
+ /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
+ /* ------------------------------- */
+ W(0x00, 0,0,1,1,0,0,1,0,1,1,0,0,0,0,0,0)| /* 00 */
+ W(0x10, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0), /* 10 */
+ W(0x20, 1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0)| /* 20 */
+ W(0x30, 0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0), /* 30 */
+ W(0x40, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1)| /* 40 */
+ W(0x50, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0), /* 50 */
+ W(0x60, 1,1,1,1,1,1,1,1,1,1,1,1,0,0,1,1)| /* 60 */
+ W(0x70, 0,0,0,0,1,1,1,1,0,0,0,0,0,0,1,1), /* 70 */
+ W(0x80, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)| /* 80 */
+ W(0x90, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1), /* 90 */
+ W(0xa0, 1,1,0,1,1,1,0,0,1,1,0,1,1,1,0,1)| /* a0 */
+ W(0xb0, 1,1,1,1,1,1,1,1,0,0,0,1,1,1,1,1), /* b0 */
+ W(0xc0, 1,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1)| /* c0 */
+ W(0xd0, 0,1,1,1,0,1,0,0,1,1,0,1,1,1,0,1), /* d0 */
+ W(0xe0, 0,1,1,0,0,1,0,0,1,1,0,1,1,1,0,1)| /* e0 */
+ W(0xf0, 0,1,1,1,0,1,0,0,1,1,1,0,1,1,1,0) /* f0 */
+ /* ------------------------------- */
+ /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
};
-const int kretprobe_blacklist_size = ARRAY_SIZE(kretprobe_blacklist);
-
-/*
- * returns non-zero if opcode modifies the interrupt flag.
- */
-static __always_inline int is_IF_modifier(kprobe_opcode_t *insn)
-{
- switch (*insn) {
- case 0xfa: /* cli */
- case 0xfb: /* sti */
- case 0xcf: /* iret/iretd */
- case 0x9d: /* popf/popfd */
- return 1;
- }
-
- if (*insn >= 0x40 && *insn <= 0x4f && *++insn == 0xcf)
- return 1;
- return 0;
-}
-
-int __kprobes arch_prepare_kprobe(struct kprobe *p)
-{
- /* insn: must be on special executable page on x86_64. */
- p->ainsn.insn = get_insn_slot();
- if (!p->ainsn.insn) {
- return -ENOMEM;
- }
- arch_copy_kprobe(p);
- return 0;
-}
+#undef W
-/*
- * Determine if the instruction uses the %rip-relative addressing mode.
- * If it does, return the address of the 32-bit displacement word.
- * If not, return null.
- */
-static s32 __kprobes *is_riprel(u8 *insn)
-{
#define W(row,b0,b1,b2,b3,b4,b5,b6,b7,b8,b9,ba,bb,bc,bd,be,bf) \
(((b0##UL << 0x0)|(b1##UL << 0x1)|(b2##UL << 0x2)|(b3##UL << 0x3) | \
(b4##UL << 0x4)|(b5##UL << 0x5)|(b6##UL << 0x6)|(b7##UL << 0x7) | \
(b8##UL << 0x8)|(b9##UL << 0x9)|(ba##UL << 0xa)|(bb##UL << 0xb) | \
(bc##UL << 0xc)|(bd##UL << 0xd)|(be##UL << 0xe)|(bf##UL << 0xf)) \
<< (row % 64))
- static const u64 onebyte_has_modrm[256 / 64] = {
+static const u64 onebyte_has_modrm[256 / 64] = {
/* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
/* ------------------------------- */
W(0x00, 1,1,1,1,0,0,0,0,1,1,1,1,0,0,0,0)| /* 00 */
@@ -118,8 +110,8 @@ static s32 __kprobes *is_riprel(u8 *insn
W(0xf0, 0,0,0,0,0,0,1,1,0,0,0,0,0,0,1,1) /* f0 */
/* ------------------------------- */
/* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
- };
- static const u64 twobyte_has_modrm[256 / 64] = {
+};
+static const u64 twobyte_has_modrm[256 / 64] = {
/* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
/* ------------------------------- */
W(0x00, 1,1,1,1,0,0,0,0,0,0,0,0,0,1,0,1)| /* 0f */
@@ -140,8 +132,46 @@ static s32 __kprobes *is_riprel(u8 *insn
W(0xf0, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0) /* ff */
/* ------------------------------- */
/* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
- };
+};
#undef W
+
+struct kretprobe_blackpoint kretprobe_blacklist[] = {
+ {"__switch_to", }, /* This function switches only current task, but
+ doesn't switch kernel stack.*/
+ {NULL, NULL} /* Terminator */
+};
+const int kretprobe_blacklist_size = ARRAY_SIZE(kretprobe_blacklist);
+
+/*
+ * returns non-zero if opcode modifies the interrupt flag.
+ */
+static __always_inline int is_IF_modifier(kprobe_opcode_t *insn)
+{
+ switch (*insn) {
+ case 0xfa: /* cli */
+ case 0xfb: /* sti */
+ case 0xcf: /* iret/iretd */
+ case 0x9d: /* popf/popfd */
+ return 1;
+ }
+
+ /*
+ * on 64 bit x86, 0x40-0x4f are prefixes so we need to look
+ * at the next byte instead.. but of course not recurse infinitely
+ */
+ if (*insn >= 0x40 && *insn <= 0x4f && *insn > 0x4f)
+ return is_IF_modifier(++insn);
+ return 0;
+}
+
+
+/*
+ * Determine if the instruction uses the %rip-relative addressing mode.
+ * If it does, return the address of the 32-bit displacement word.
+ * If not, return null.
+ */
+static s32 __kprobes *is_riprel(u8 *insn)
+{
int need_modrm;
/* Skip legacy instruction prefixes. */
@@ -213,6 +243,16 @@ static void __kprobes arch_copy_kprobe(s
p->opcode = *p->addr;
}
+int __kprobes arch_prepare_kprobe(struct kprobe *p)
+{
+ /* insn: must be on special executable page on x86. */
+ p->ainsn.insn = get_insn_slot();
+ if (!p->ainsn.insn)
+ return -ENOMEM;
+ arch_copy_kprobe(p);
+ return 0;
+}
+
void __kprobes arch_arm_kprobe(struct kprobe *p)
{
text_poke(p->addr, ((unsigned char []){BREAKPOINT_INSTRUCTION}), 1);
@@ -234,26 +274,26 @@ static void __kprobes save_previous_kpro
{
kcb->prev_kprobe.kp = kprobe_running();
kcb->prev_kprobe.status = kcb->kprobe_status;
- kcb->prev_kprobe.old_rflags = kcb->kprobe_old_rflags;
- kcb->prev_kprobe.saved_rflags = kcb->kprobe_saved_rflags;
+ kcb->prev_kprobe.old_flags = kcb->kprobe_old_flags;
+ kcb->prev_kprobe.saved_flags = kcb->kprobe_saved_flags;
}
static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb)
{
__get_cpu_var(current_kprobe) = kcb->prev_kprobe.kp;
kcb->kprobe_status = kcb->prev_kprobe.status;
- kcb->kprobe_old_rflags = kcb->prev_kprobe.old_rflags;
- kcb->kprobe_saved_rflags = kcb->prev_kprobe.saved_rflags;
+ kcb->kprobe_old_flags = kcb->prev_kprobe.old_flags;
+ kcb->kprobe_saved_flags = kcb->prev_kprobe.saved_flags;
}
static void __kprobes set_current_kprobe(struct kprobe *p, struct pt_regs *regs,
struct kprobe_ctlblk *kcb)
{
__get_cpu_var(current_kprobe) = p;
- kcb->kprobe_saved_rflags = kcb->kprobe_old_rflags
+ kcb->kprobe_saved_flags = kcb->kprobe_old_flags
= (regs->eflags & (TF_MASK | IF_MASK));
if (is_IF_modifier(p->ainsn.insn))
- kcb->kprobe_saved_rflags &= ~IF_MASK;
+ kcb->kprobe_saved_flags &= ~IF_MASK;
}
static void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs)
@@ -274,17 +314,20 @@ void __kprobes arch_prepare_kretprobe(st
unsigned long *sara = (unsigned long *)regs->rsp;
ri->ret_addr = (kprobe_opcode_t *) *sara;
+
/* Replace the return addr with trampoline addr */
*sara = (unsigned long) &kretprobe_trampoline;
}
-int __kprobes kprobe_handler(struct pt_regs *regs)
+static int __kprobes kprobe_handler(struct pt_regs *regs)
{
struct kprobe *p;
int ret = 0;
- kprobe_opcode_t *addr = (kprobe_opcode_t *)(regs->rip - sizeof(kprobe_opcode_t));
+ kprobe_opcode_t *addr;
struct kprobe_ctlblk *kcb;
+ addr = (kprobe_opcode_t *)(regs->rip - sizeof(kprobe_opcode_t));
+
/*
* We don't want to be preempted for the entire
* duration of kprobe processing
@@ -299,7 +342,7 @@ int __kprobes kprobe_handler(struct pt_r
if (kcb->kprobe_status == KPROBE_HIT_SS &&
*p->ainsn.insn == BREAKPOINT_INSTRUCTION) {
regs->eflags &= ~TF_MASK;
- regs->eflags |= kcb->kprobe_saved_rflags;
+ regs->eflags |= kcb->kprobe_saved_flags;
goto no_kprobe;
} else if (kcb->kprobe_status == KPROBE_HIT_SSDONE) {
/* TODO: Provide re-entrancy from
@@ -385,7 +428,7 @@ no_kprobe:
* here. When a retprobed function returns, this probe is hit and
* trampoline_probe_handler() runs, calling the kretprobe's handler.
*/
- void kretprobe_trampoline_holder(void)
+ void __kprobes kretprobe_trampoline_holder(void)
{
asm volatile ( ".global kretprobe_trampoline\n"
"kretprobe_trampoline: \n"
@@ -497,7 +540,7 @@ static void __kprobes resume_execution(s
switch (*insn) {
case 0x9c: /* pushfl */
*tos &= ~(TF_MASK | IF_MASK);
- *tos |= kcb->kprobe_old_rflags;
+ *tos |= kcb->kprobe_old_flags;
break;
case 0xc3: /* ret/lret */
case 0xcb:
@@ -550,7 +593,7 @@ int __kprobes post_kprobe_handler(struct
}
resume_execution(cur, regs, kcb);
- regs->eflags |= kcb->kprobe_saved_rflags;
+ regs->eflags |= kcb->kprobe_saved_flags;
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
if (raw_irqs_disabled_flags(regs->eflags))
trace_hardirqs_off();
@@ -595,7 +638,7 @@ int __kprobes kprobe_fault_handler(struc
* normal page fault.
*/
regs->rip = (unsigned long)cur->addr;
- regs->eflags |= kcb->kprobe_old_rflags;
+ regs->eflags |= kcb->kprobe_old_flags;
if (kcb->kprobe_status == KPROBE_REENTER)
restore_previous_kprobe(kcb);
else
@@ -684,8 +727,9 @@ int __kprobes setjmp_pre_handler(struct
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
kcb->jprobe_saved_regs = *regs;
- kcb->jprobe_saved_rsp = (long *) regs->rsp;
- addr = (unsigned long)(kcb->jprobe_saved_rsp);
+ kcb->jprobe_saved_sp = (long *) regs->rsp;
+ addr = (unsigned long)(kcb->jprobe_saved_sp);
+
/*
* As Linus pointed out, gcc assumes that the callee
* owns the argument space and could overwrite it, e.g.
@@ -710,23 +754,23 @@ void __kprobes jprobe_return(void)
" .globl jprobe_return_end \n"
" jprobe_return_end: \n"
" nop \n"::"b"
- (kcb->jprobe_saved_rsp):"memory");
+ (kcb->jprobe_saved_sp):"memory");
}
int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
{
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
u8 *addr = (u8 *) (regs->rip - 1);
- unsigned long stack_addr = (unsigned long)(kcb->jprobe_saved_rsp);
+ unsigned long stack_addr = (unsigned long)(kcb->jprobe_saved_sp);
struct jprobe *jp = container_of(p, struct jprobe, kp);
if ((addr > (u8 *) jprobe_return) && (addr < (u8 *) jprobe_return_end)) {
- if ((long *)regs->rsp != kcb->jprobe_saved_rsp) {
+ if ((long *)regs->rsp != kcb->jprobe_saved_sp) {
struct pt_regs *saved_regs =
- container_of(kcb->jprobe_saved_rsp,
+ container_of(kcb->jprobe_saved_sp,
struct pt_regs, rsp);
printk("current rsp %p does not match saved rsp %p\n",
- (long *)regs->rsp, kcb->jprobe_saved_rsp);
+ (long *)regs->rsp, kcb->jprobe_saved_sp);
printk("Saved registers for jprobe %p\n", jp);
show_registers(saved_regs);
printk("Current registers\n");
Index: linux-2.6.24-rc1/arch/x86/mm/fault_32.c
===================================================================
--- linux-2.6.24-rc1.orig/arch/x86/mm/fault_32.c
+++ linux-2.6.24-rc1/arch/x86/mm/fault_32.c
@@ -25,7 +25,6 @@
#include <linux/kprobes.h>
#include <linux/uaccess.h>
#include <linux/kdebug.h>
-#include <linux/kprobes.h>
#include <asm/system.h>
#include <asm/desc.h>
Index: linux-2.6.24-rc1/include/asm-x86/kprobes_32.h
===================================================================
--- linux-2.6.24-rc1.orig/include/asm-x86/kprobes_32.h
+++ linux-2.6.24-rc1/include/asm-x86/kprobes_32.h
@@ -2,7 +2,6 @@
#define _ASM_KPROBES_H
/*
* Kernel Probes (KProbes)
- * include/asm-i386/kprobes.h
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -23,14 +22,17 @@
* 2002-Oct Created by Vamsi Krishna S <vamsi_krishna@xxxxxxxxxx> Kernel
* Probes initial implementation ( includes suggestions from
* Rusty Russell).
+ * 2004-Oct Prasanna S Panchamukhi <prasanna@xxxxxxxxxx> and Jim Keniston
+ * kenistoj@xxxxxxxxxx adopted from i386.
*/
#include <linux/types.h>
#include <linux/ptrace.h>
+#include <linux/percpu.h>
#define __ARCH_WANT_KPROBES_INSN_SLOT
-struct kprobe;
struct pt_regs;
+struct kprobe;
typedef u8 kprobe_opcode_t;
#define BREAKPOINT_INSTRUCTION 0xcc
@@ -64,16 +66,16 @@ struct arch_specific_insn {
struct prev_kprobe {
struct kprobe *kp;
unsigned long status;
- unsigned long old_eflags;
- unsigned long saved_eflags;
+ unsigned long old_flags;
+ unsigned long saved_flags;
};
/* per-cpu kprobe control block */
struct kprobe_ctlblk {
unsigned long kprobe_status;
- unsigned long kprobe_old_eflags;
- unsigned long kprobe_saved_eflags;
- long *jprobe_saved_esp;
+ unsigned long kprobe_old_flags;
+ unsigned long kprobe_saved_flags;
+ long *jprobe_saved_sp;
struct pt_regs jprobe_saved_regs;
kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
struct prev_kprobe prev_kprobe;
@@ -88,7 +90,7 @@ static inline void restore_interrupts(st
local_irq_enable();
}
+extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
extern int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
-extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
#endif /* _ASM_KPROBES_H */
Index: linux-2.6.24-rc1/include/asm-x86/kprobes_64.h
===================================================================
--- linux-2.6.24-rc1.orig/include/asm-x86/kprobes_64.h
+++ linux-2.6.24-rc1/include/asm-x86/kprobes_64.h
@@ -2,7 +2,6 @@
#define _ASM_KPROBES_H
/*
* Kernel Probes (KProbes)
- * include/asm-x86_64/kprobes.h
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -20,6 +19,9 @@
*
* Copyright (C) IBM Corporation, 2002, 2004
*
+ * 2002-Oct Created by Vamsi Krishna S <vamsi_krishna@xxxxxxxxxx> Kernel
+ * Probes initial implementation ( includes suggestions from
+ * Rusty Russell).
* 2004-Oct Prasanna S Panchamukhi <prasanna@xxxxxxxxxx> and Jim Keniston
* kenistoj@xxxxxxxxxx adopted from i386.
*/
@@ -34,6 +36,7 @@ struct kprobe;
typedef u8 kprobe_opcode_t;
#define BREAKPOINT_INSTRUCTION 0xcc
+#define RELATIVEJUMP_INSTRUCTION 0xe9
#define MAX_INSN_SIZE 15
#define MAX_STACK_SIZE 64
#define MIN_STACK_SIZE(ADDR) (((MAX_STACK_SIZE) < \
@@ -42,31 +45,37 @@ typedef u8 kprobe_opcode_t;
: (((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR)))
#define ARCH_SUPPORTS_KRETPROBES
+#define flush_insn_slot(p) do { } while (0)
+
extern const int kretprobe_blacklist_size;
+void arch_remove_kprobe(struct kprobe *p);
void kretprobe_trampoline(void);
-extern void arch_remove_kprobe(struct kprobe *p);
-#define flush_insn_slot(p) do { } while (0)
/* Architecture specific copy of original instruction*/
struct arch_specific_insn {
/* copy of the original instruction */
kprobe_opcode_t *insn;
+ /*
+ * If this flag is not 0, this kprobe can be boost when its
+ * post_handler and break_handler is not set.
+ */
+ int boostable;
};
struct prev_kprobe {
struct kprobe *kp;
unsigned long status;
- unsigned long old_rflags;
- unsigned long saved_rflags;
+ unsigned long old_flags;
+ unsigned long saved_flags;
};
/* per-cpu kprobe control block */
struct kprobe_ctlblk {
unsigned long kprobe_status;
- unsigned long kprobe_old_rflags;
- unsigned long kprobe_saved_rflags;
- long *jprobe_saved_rsp;
+ unsigned long kprobe_old_flags;
+ unsigned long kprobe_saved_flags;
+ long *jprobe_saved_sp;
struct pt_regs jprobe_saved_regs;
kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
struct prev_kprobe prev_kprobe;
@@ -81,10 +90,7 @@ static inline void restore_interrupts(st
local_irq_enable();
}
-extern int post_kprobe_handler(struct pt_regs *regs);
extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
-extern int kprobe_handler(struct pt_regs *regs);
-
extern int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
#endif /* _ASM_KPROBES_H */
Index: linux-2.6.24-rc1/arch/x86/mm/fault_64.c
===================================================================
--- linux-2.6.24-rc1.orig/arch/x86/mm/fault_64.c
+++ linux-2.6.24-rc1/arch/x86/mm/fault_64.c
@@ -25,7 +25,6 @@
#include <linux/kprobes.h>
#include <linux/uaccess.h>
#include <linux/kdebug.h>
-#include <linux/kprobes.h>
#include <asm/system.h>
#include <asm/pgalloc.h>
-
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