From 080e0013269e9fd428fd834e8a915a80fe6c8ae9 Mon Sep 17 00:00:00 2001 From: Jon Medhurst Date: Sun, 3 Jul 2011 14:31:58 +0100 Subject: [PATCH] ARM: kprobes: Decode 32-bit Thumb data-processing (shifted register) instructions Signed-off-by: Jon Medhurst Acked-by: Nicolas Pitre --- arch/arm/kernel/kprobes-thumb.c | 93 +++++++++++++++++++++++++++++++++ 1 file changed, 93 insertions(+) diff --git a/arch/arm/kernel/kprobes-thumb.c b/arch/arm/kernel/kprobes-thumb.c index dfaea25c606..eac945ccf61 100644 --- a/arch/arm/kernel/kprobes-thumb.c +++ b/arch/arm/kernel/kprobes-thumb.c @@ -97,6 +97,33 @@ t32_emulate_ldrdstrd(struct kprobe *p, struct pt_regs *regs) regs->uregs[rt2] = rt2v; } +static void __kprobes +t32_emulate_rd8rn16rm0_rwflags(struct kprobe *p, struct pt_regs *regs) +{ + kprobe_opcode_t insn = p->opcode; + int rd = (insn >> 8) & 0xf; + int rn = (insn >> 16) & 0xf; + int rm = insn & 0xf; + + register unsigned long rdv asm("r1") = regs->uregs[rd]; + register unsigned long rnv asm("r2") = regs->uregs[rn]; + register unsigned long rmv asm("r3") = regs->uregs[rm]; + unsigned long cpsr = regs->ARM_cpsr; + + __asm__ __volatile__ ( + "msr cpsr_fs, %[cpsr] \n\t" + "blx %[fn] \n\t" + "mrs %[cpsr], cpsr \n\t" + : "=r" (rdv), [cpsr] "=r" (cpsr) + : "0" (rdv), "r" (rnv), "r" (rmv), + "1" (cpsr), [fn] "r" (p->ainsn.insn_fn) + : "lr", "memory", "cc" + ); + + regs->uregs[rd] = rdv; + regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK); +} + static const union decode_item t32_table_1110_100x_x0xx[] = { /* Load/store multiple instructions */ @@ -154,6 +181,66 @@ static const union decode_item t32_table_1110_100x_x1xx[] = { DECODE_END }; +static const union decode_item t32_table_1110_101x[] = { + /* Data-processing (shifted register) */ + + /* TST 1110 1010 0001 xxxx xxxx 1111 xxxx xxxx */ + /* TEQ 1110 1010 1001 xxxx xxxx 1111 xxxx xxxx */ + DECODE_EMULATEX (0xff700f00, 0xea100f00, t32_emulate_rd8rn16rm0_rwflags, + REGS(NOSPPC, 0, 0, 0, NOSPPC)), + + /* CMN 1110 1011 0001 xxxx xxxx 1111 xxxx xxxx */ + DECODE_OR (0xfff00f00, 0xeb100f00), + /* CMP 1110 1011 1011 xxxx xxxx 1111 xxxx xxxx */ + DECODE_EMULATEX (0xfff00f00, 0xebb00f00, t32_emulate_rd8rn16rm0_rwflags, + REGS(NOPC, 0, 0, 0, NOSPPC)), + + /* MOV 1110 1010 010x 1111 xxxx xxxx xxxx xxxx */ + /* MVN 1110 1010 011x 1111 xxxx xxxx xxxx xxxx */ + DECODE_EMULATEX (0xffcf0000, 0xea4f0000, t32_emulate_rd8rn16rm0_rwflags, + REGS(0, 0, NOSPPC, 0, NOSPPC)), + + /* ??? 1110 1010 101x xxxx xxxx xxxx xxxx xxxx */ + /* ??? 1110 1010 111x xxxx xxxx xxxx xxxx xxxx */ + DECODE_REJECT (0xffa00000, 0xeaa00000), + /* ??? 1110 1011 001x xxxx xxxx xxxx xxxx xxxx */ + DECODE_REJECT (0xffe00000, 0xeb200000), + /* ??? 1110 1011 100x xxxx xxxx xxxx xxxx xxxx */ + DECODE_REJECT (0xffe00000, 0xeb800000), + /* ??? 1110 1011 111x xxxx xxxx xxxx xxxx xxxx */ + DECODE_REJECT (0xffe00000, 0xebe00000), + + /* ADD/SUB SP, SP, Rm, LSL #0..3 */ + /* 1110 1011 x0xx 1101 x000 1101 xx00 xxxx */ + DECODE_EMULATEX (0xff4f7f30, 0xeb0d0d00, t32_emulate_rd8rn16rm0_rwflags, + REGS(SP, 0, SP, 0, NOSPPC)), + + /* ADD/SUB SP, SP, Rm, shift */ + /* 1110 1011 x0xx 1101 xxxx 1101 xxxx xxxx */ + DECODE_REJECT (0xff4f0f00, 0xeb0d0d00), + + /* ADD/SUB Rd, SP, Rm, shift */ + /* 1110 1011 x0xx 1101 xxxx xxxx xxxx xxxx */ + DECODE_EMULATEX (0xff4f0000, 0xeb0d0000, t32_emulate_rd8rn16rm0_rwflags, + REGS(SP, 0, NOPC, 0, NOSPPC)), + + /* AND 1110 1010 000x xxxx xxxx xxxx xxxx xxxx */ + /* BIC 1110 1010 001x xxxx xxxx xxxx xxxx xxxx */ + /* ORR 1110 1010 010x xxxx xxxx xxxx xxxx xxxx */ + /* ORN 1110 1010 011x xxxx xxxx xxxx xxxx xxxx */ + /* EOR 1110 1010 100x xxxx xxxx xxxx xxxx xxxx */ + /* PKH 1110 1010 110x xxxx xxxx xxxx xxxx xxxx */ + /* ADD 1110 1011 000x xxxx xxxx xxxx xxxx xxxx */ + /* ADC 1110 1011 010x xxxx xxxx xxxx xxxx xxxx */ + /* SBC 1110 1011 011x xxxx xxxx xxxx xxxx xxxx */ + /* SUB 1110 1011 101x xxxx xxxx xxxx xxxx xxxx */ + /* RSB 1110 1011 110x xxxx xxxx xxxx xxxx xxxx */ + DECODE_EMULATEX (0xfe000000, 0xea000000, t32_emulate_rd8rn16rm0_rwflags, + REGS(NOSPPC, 0, NOSPPC, 0, NOSPPC)), + + DECODE_END +}; + static const union decode_item t32_table_1111_0xxx___1[] = { /* Branches and miscellaneous control */ @@ -183,6 +270,12 @@ const union decode_item kprobe_decode_thumb32_table[] = { */ DECODE_TABLE (0xfe400000, 0xe8400000, t32_table_1110_100x_x1xx), + /* + * Data-processing (shifted register) + * 1110 101x xxxx xxxx xxxx xxxx xxxx xxxx + */ + DECODE_TABLE (0xfe000000, 0xea000000, t32_table_1110_101x), + /* * Branches and miscellaneous control * 1111 0xxx xxxx xxxx 1xxx xxxx xxxx xxxx -- 2.39.5