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Diffstat (limited to 'arch/arm/kernel/kprobes-thumb.c')
-rw-r--r--arch/arm/kernel/kprobes-thumb.c33
1 files changed, 33 insertions, 0 deletions
diff --git a/arch/arm/kernel/kprobes-thumb.c b/arch/arm/kernel/kprobes-thumb.c
index 632a5e8f5977..2b30828d5f0c 100644
--- a/arch/arm/kernel/kprobes-thumb.c
+++ b/arch/arm/kernel/kprobes-thumb.c
@@ -74,6 +74,28 @@ t16_simulate_ldrstr_sp_relative(struct kprobe *p, struct pt_regs *regs)
base[index] = regs->uregs[rt];
}
+static void __kprobes
+t16_simulate_reladr(struct kprobe *p, struct pt_regs *regs)
+{
+ kprobe_opcode_t insn = p->opcode;
+ unsigned long base = (insn & 0x800) ? regs->ARM_sp
+ : (thumb_probe_pc(p) & ~3);
+ long offset = insn & 0xff;
+ int rt = (insn >> 8) & 0x7;
+ regs->uregs[rt] = base + offset * 4;
+}
+
+static void __kprobes
+t16_simulate_add_sp_imm(struct kprobe *p, struct pt_regs *regs)
+{
+ kprobe_opcode_t insn = p->opcode;
+ long imm = insn & 0x7f;
+ if (insn & 0x80) /* SUB */
+ regs->ARM_sp -= imm * 4;
+ else /* ADD */
+ regs->ARM_sp += imm * 4;
+}
+
static unsigned long __kprobes
t16_emulate_loregs(struct kprobe *p, struct pt_regs *regs)
{
@@ -154,6 +176,10 @@ t16_decode_hiregs(kprobe_opcode_t insn, struct arch_specific_insn *asi)
static const union decode_item t16_table_1011[] = {
/* Miscellaneous 16-bit instructions */
+ /* ADD (SP plus immediate) 1011 0000 0xxx xxxx */
+ /* SUB (SP minus immediate) 1011 0000 1xxx xxxx */
+ DECODE_SIMULATE (0xff00, 0xb000, t16_simulate_add_sp_imm),
+
/*
* If-Then, and hints
* 1011 1111 xxxx xxxx
@@ -274,6 +300,13 @@ const union decode_item kprobe_decode_thumb16_table[] = {
DECODE_SIMULATE (0xf000, 0x9000, t16_simulate_ldrstr_sp_relative),
/*
+ * Generate PC-/SP-relative address
+ * ADR (literal) 1010 0xxx xxxx xxxx
+ * ADD (SP plus immediate) 1010 1xxx xxxx xxxx
+ */
+ DECODE_SIMULATE (0xf000, 0xa000, t16_simulate_reladr),
+
+ /*
* Miscellaneous 16-bit instructions
* 1011 xxxx xxxx xxxx
*/