diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/uprobes.h | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/uprobes.c | 107 | ||||
| -rw-r--r-- | arch/x86/tools/Makefile | 12 | ||||
| -rw-r--r-- | arch/x86/tools/insn_decoder_test.c (renamed from arch/x86/tools/test_get_len.c) | 43 | ||||
| -rw-r--r-- | arch/x86/tools/objdump_reformat.awk (renamed from arch/x86/tools/distill.awk) | 4 |
5 files changed, 140 insertions, 30 deletions
diff --git a/arch/x86/include/asm/uprobes.h b/arch/x86/include/asm/uprobes.h index 74f4c2ff6427..d8bfa98fca98 100644 --- a/arch/x86/include/asm/uprobes.h +++ b/arch/x86/include/asm/uprobes.h @@ -53,6 +53,10 @@ struct arch_uprobe { u8 fixups; u8 ilen; } defparam; + struct { + u8 reg_offset; /* to the start of pt_regs */ + u8 ilen; + } push; }; }; diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c index a3755d293a48..85c7ef23d99f 100644 --- a/arch/x86/kernel/uprobes.c +++ b/arch/x86/kernel/uprobes.c @@ -528,11 +528,11 @@ static int default_pre_xol_op(struct arch_uprobe *auprobe, struct pt_regs *regs) return 0; } -static int push_ret_address(struct pt_regs *regs, unsigned long ip) +static int emulate_push_stack(struct pt_regs *regs, unsigned long val) { unsigned long new_sp = regs->sp - sizeof_long(); - if (copy_to_user((void __user *)new_sp, &ip, sizeof_long())) + if (copy_to_user((void __user *)new_sp, &val, sizeof_long())) return -EFAULT; regs->sp = new_sp; @@ -566,7 +566,7 @@ static int default_post_xol_op(struct arch_uprobe *auprobe, struct pt_regs *regs regs->ip += correction; } else if (auprobe->defparam.fixups & UPROBE_FIX_CALL) { regs->sp += sizeof_long(); /* Pop incorrect return address */ - if (push_ret_address(regs, utask->vaddr + auprobe->defparam.ilen)) + if (emulate_push_stack(regs, utask->vaddr + auprobe->defparam.ilen)) return -ERESTART; } /* popf; tell the caller to not touch TF */ @@ -655,7 +655,7 @@ static bool branch_emulate_op(struct arch_uprobe *auprobe, struct pt_regs *regs) * * But there is corner case, see the comment in ->post_xol(). */ - if (push_ret_address(regs, new_ip)) + if (emulate_push_stack(regs, new_ip)) return false; } else if (!check_jmp_cond(auprobe, regs)) { offs = 0; @@ -665,6 +665,16 @@ static bool branch_emulate_op(struct arch_uprobe *auprobe, struct pt_regs *regs) return true; } +static bool push_emulate_op(struct arch_uprobe *auprobe, struct pt_regs *regs) +{ + unsigned long *src_ptr = (void *)regs + auprobe->push.reg_offset; + + if (emulate_push_stack(regs, *src_ptr)) + return false; + regs->ip += auprobe->push.ilen; + return true; +} + static int branch_post_xol_op(struct arch_uprobe *auprobe, struct pt_regs *regs) { BUG_ON(!branch_is_call(auprobe)); @@ -703,6 +713,10 @@ static const struct uprobe_xol_ops branch_xol_ops = { .post_xol = branch_post_xol_op, }; +static const struct uprobe_xol_ops push_xol_ops = { + .emulate = push_emulate_op, +}; + /* Returns -ENOSYS if branch_xol_ops doesn't handle this insn */ static int branch_setup_xol_ops(struct arch_uprobe *auprobe, struct insn *insn) { @@ -750,6 +764,87 @@ static int branch_setup_xol_ops(struct arch_uprobe *auprobe, struct insn *insn) return 0; } +/* Returns -ENOSYS if push_xol_ops doesn't handle this insn */ +static int push_setup_xol_ops(struct arch_uprobe *auprobe, struct insn *insn) +{ + u8 opc1 = OPCODE1(insn), reg_offset = 0; + + if (opc1 < 0x50 || opc1 > 0x57) + return -ENOSYS; + + if (insn->length > 2) + return -ENOSYS; + if (insn->length == 2) { + /* only support rex_prefix 0x41 (x64 only) */ +#ifdef CONFIG_X86_64 + if (insn->rex_prefix.nbytes != 1 || + insn->rex_prefix.bytes[0] != 0x41) + return -ENOSYS; + + switch (opc1) { + case 0x50: + reg_offset = offsetof(struct pt_regs, r8); + break; + case 0x51: + reg_offset = offsetof(struct pt_regs, r9); + break; + case 0x52: + reg_offset = offsetof(struct pt_regs, r10); + break; + case 0x53: + reg_offset = offsetof(struct pt_regs, r11); + break; + case 0x54: + reg_offset = offsetof(struct pt_regs, r12); + break; + case 0x55: + reg_offset = offsetof(struct pt_regs, r13); + break; + case 0x56: + reg_offset = offsetof(struct pt_regs, r14); + break; + case 0x57: + reg_offset = offsetof(struct pt_regs, r15); + break; + } +#else + return -ENOSYS; +#endif + } else { + switch (opc1) { + case 0x50: + reg_offset = offsetof(struct pt_regs, ax); + break; + case 0x51: + reg_offset = offsetof(struct pt_regs, cx); + break; + case 0x52: + reg_offset = offsetof(struct pt_regs, dx); + break; + case 0x53: + reg_offset = offsetof(struct pt_regs, bx); + break; + case 0x54: + reg_offset = offsetof(struct pt_regs, sp); + break; + case 0x55: + reg_offset = offsetof(struct pt_regs, bp); + break; + case 0x56: + reg_offset = offsetof(struct pt_regs, si); + break; + case 0x57: + reg_offset = offsetof(struct pt_regs, di); + break; + } + } + + auprobe->push.reg_offset = reg_offset; + auprobe->push.ilen = insn->length; + auprobe->ops = &push_xol_ops; + return 0; +} + /** * arch_uprobe_analyze_insn - instruction analysis including validity and fixups. * @mm: the probed address space. @@ -771,6 +866,10 @@ int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, if (ret != -ENOSYS) return ret; + ret = push_setup_xol_ops(auprobe, &insn); + if (ret != -ENOSYS) + return ret; + /* * Figure out which fixups default_post_xol_op() will need to perform, * and annotate defparam->fixups accordingly. diff --git a/arch/x86/tools/Makefile b/arch/x86/tools/Makefile index 972b8e8d939c..09af7ff53044 100644 --- a/arch/x86/tools/Makefile +++ b/arch/x86/tools/Makefile @@ -13,28 +13,28 @@ else posttest_64bit = -n endif -distill_awk = $(srctree)/arch/x86/tools/distill.awk +reformatter = $(srctree)/arch/x86/tools/objdump_reformat.awk chkobjdump = $(srctree)/arch/x86/tools/chkobjdump.awk quiet_cmd_posttest = TEST $@ - cmd_posttest = ($(OBJDUMP) -v | $(AWK) -f $(chkobjdump)) || $(OBJDUMP) -d -j .text $(objtree)/vmlinux | $(AWK) -f $(distill_awk) | $(obj)/test_get_len $(posttest_64bit) $(posttest_verbose) + cmd_posttest = ($(OBJDUMP) -v | $(AWK) -f $(chkobjdump)) || $(OBJDUMP) -d -j .text $(objtree)/vmlinux | $(AWK) -f $(reformatter) | $(obj)/insn_decoder_test $(posttest_64bit) $(posttest_verbose) quiet_cmd_sanitytest = TEST $@ cmd_sanitytest = $(obj)/insn_sanity $(posttest_64bit) -m 1000000 -posttest: $(obj)/test_get_len vmlinux $(obj)/insn_sanity +posttest: $(obj)/insn_decoder_test vmlinux $(obj)/insn_sanity $(call cmd,posttest) $(call cmd,sanitytest) -hostprogs-y += test_get_len insn_sanity +hostprogs-y += insn_decoder_test insn_sanity # -I needed for generated C source and C source which in the kernel tree. -HOSTCFLAGS_test_get_len.o := -Wall -I$(objtree)/arch/x86/lib/ -I$(srctree)/arch/x86/include/uapi/ -I$(srctree)/arch/x86/include/ -I$(srctree)/arch/x86/lib/ -I$(srctree)/include/uapi/ +HOSTCFLAGS_insn_decoder_test.o := -Wall -I$(objtree)/arch/x86/lib/ -I$(srctree)/arch/x86/include/uapi/ -I$(srctree)/arch/x86/include/ -I$(srctree)/arch/x86/lib/ -I$(srctree)/include/uapi/ HOSTCFLAGS_insn_sanity.o := -Wall -I$(objtree)/arch/x86/lib/ -I$(srctree)/arch/x86/include/ -I$(srctree)/arch/x86/lib/ -I$(srctree)/include/ # Dependencies are also needed. -$(obj)/test_get_len.o: $(srctree)/arch/x86/lib/insn.c $(srctree)/arch/x86/lib/inat.c $(srctree)/arch/x86/include/asm/inat_types.h $(srctree)/arch/x86/include/asm/inat.h $(srctree)/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c +$(obj)/insn_decoder_test.o: $(srctree)/arch/x86/lib/insn.c $(srctree)/arch/x86/lib/inat.c $(srctree)/arch/x86/include/asm/inat_types.h $(srctree)/arch/x86/include/asm/inat.h $(srctree)/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c $(obj)/insn_sanity.o: $(srctree)/arch/x86/lib/insn.c $(srctree)/arch/x86/lib/inat.c $(srctree)/arch/x86/include/asm/inat_types.h $(srctree)/arch/x86/include/asm/inat.h $(srctree)/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c diff --git a/arch/x86/tools/test_get_len.c b/arch/x86/tools/insn_decoder_test.c index ecf31e0358c8..a3b4fd954931 100644 --- a/arch/x86/tools/test_get_len.c +++ b/arch/x86/tools/insn_decoder_test.c @@ -9,10 +9,6 @@ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - * * Copyright (C) IBM Corporation, 2009 */ @@ -21,6 +17,7 @@ #include <string.h> #include <assert.h> #include <unistd.h> +#include <stdarg.h> #define unlikely(cond) (cond) @@ -33,7 +30,7 @@ * particular. See if insn_get_length() and the disassembler agree * on the length of each instruction in an elf disassembly. * - * Usage: objdump -d a.out | awk -f distill.awk | ./test_get_len + * Usage: objdump -d a.out | awk -f objdump_reformat.awk | ./insn_decoder_test */ const char *prog; @@ -42,8 +39,8 @@ static int x86_64; static void usage(void) { - fprintf(stderr, "Usage: objdump -d a.out | awk -f distill.awk |" - " %s [-y|-n] [-v]\n", prog); + fprintf(stderr, "Usage: objdump -d a.out | awk -f objdump_reformat.awk" + " | %s [-y|-n] [-v]\n", prog); fprintf(stderr, "\t-y 64bit mode\n"); fprintf(stderr, "\t-n 32bit mode\n"); fprintf(stderr, "\t-v verbose mode\n"); @@ -52,10 +49,21 @@ static void usage(void) static void malformed_line(const char *line, int line_nr) { - fprintf(stderr, "%s: malformed line %d:\n%s", prog, line_nr, line); + fprintf(stderr, "%s: error: malformed line %d:\n%s", + prog, line_nr, line); exit(3); } +static void pr_warn(const char *fmt, ...) +{ + va_list ap; + + fprintf(stderr, "%s: warning: ", prog); + va_start(ap, fmt); + vfprintf(stderr, fmt, ap); + va_end(ap); +} + static void dump_field(FILE *fp, const char *name, const char *indent, struct insn_field *field) { @@ -153,21 +161,20 @@ int main(int argc, char **argv) insn_get_length(&insn); if (insn.length != nb) { warnings++; - fprintf(stderr, "Warning: %s found difference at %s\n", - prog, sym); - fprintf(stderr, "Warning: %s", line); - fprintf(stderr, "Warning: objdump says %d bytes, but " - "insn_get_length() says %d\n", nb, - insn.length); + pr_warn("Found an x86 instruction decoder bug, " + "please report this.\n", sym); + pr_warn("%s", line); + pr_warn("objdump says %d bytes, but insn_get_length() " + "says %d\n", nb, insn.length); if (verbose) dump_insn(stderr, &insn); } } if (warnings) - fprintf(stderr, "Warning: decoded and checked %d" - " instructions with %d warnings\n", insns, warnings); + pr_warn("Decoded and checked %d instructions with %d " + "failures\n", insns, warnings); else - fprintf(stdout, "Success: decoded and checked %d" - " instructions\n", insns); + fprintf(stdout, "%s: success: Decoded and checked %d" + " instructions\n", prog, insns); return 0; } diff --git a/arch/x86/tools/distill.awk b/arch/x86/tools/objdump_reformat.awk index e0edeccc1429..f418c91b71f0 100644 --- a/arch/x86/tools/distill.awk +++ b/arch/x86/tools/objdump_reformat.awk @@ -1,7 +1,7 @@ #!/bin/awk -f # SPDX-License-Identifier: GPL-2.0 -# Usage: objdump -d a.out | awk -f distill.awk | ./test_get_len -# Distills the disassembly as follows: +# Usage: objdump -d a.out | awk -f objdump_reformat.awk | ./insn_decoder_test +# Reformats the disassembly as follows: # - Removes all lines except the disassembled instructions. # - For instructions that exceed 1 line (7 bytes), crams all the hex bytes # into a single line. |