2 * Dynamic Binary Instrumentation Module based on KProbes
3 * modules/kprobe/arch/asm-arm/dbi_kprobes.c
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 * Copyright (C) Samsung Electronics, 2006-2010
21 * 2006-2007 Ekaterina Gorelkina <e.gorelkina@samsung.com>: initial implementation for ARM/MIPS
22 * 2008-2009 Alexey Gerenkov <a.gerenkov@samsung.com> User-Space
23 * Probes initial implementation; Support x86.
24 * 2010 Ekaterina Gorelkina <e.gorelkina@samsung.com>: redesign module for separating core and arch parts
25 * 2010-2011 Alexander Shirshikov <a.shirshikov@samsung.com>: initial implementation for Thumb
26 * 2012 Stanislav Andreev <s.andreev@samsung.com>: added time debug profiling support; BUG() message fix
27 * 2012 Stanislav Andreev <s.andreev@samsung.com>: redesign of kprobe functionality -
28 * kprobe_handler() now called via undefined instruction hooks
29 * 2012 Stanislav Andreev <s.andreev@samsung.com>: hash tables search implemented for uprobes
32 #include <linux/module.h>
35 #include "dbi_kprobes.h"
36 #include "../dbi_kprobes.h"
38 #include "../../dbi_kdebug.h"
39 #include "../../dbi_insn_slots.h"
40 #include "../../dbi_kprobes_deps.h"
41 #include "../../dbi_uprobes.h"
43 #include <asm/cacheflush.h>
46 #include <linux/time.h>
49 #include <asm/traps.h>
50 #include <asm/ptrace.h>
51 #include <linux/list.h>
52 #include <linux/hash.h>
54 #define SUPRESS_BUG_MESSAGES
56 extern unsigned long sched_addr;
57 extern unsigned long fork_addr;
59 extern struct kprobe * per_cpu__current_kprobe;
60 extern spinlock_t kretprobe_lock;
61 extern struct kretprobe *sched_rp;
63 extern struct hlist_head kprobe_insn_pages;
64 extern struct hlist_head uprobe_insn_pages;
66 extern unsigned long (*kallsyms_search) (const char *name);
68 extern struct kprobe *kprobe_running(void);
69 extern void reset_current_kprobe(void);
70 extern struct kprobe_ctlblk *get_kprobe_ctlblk(void);
71 extern struct kprobe * current_kprobe;
73 extern struct hlist_head kprobe_table[KPROBE_TABLE_SIZE];
76 unsigned long swap_sum_time = 0;
77 unsigned long swap_sum_hit = 0;
78 EXPORT_SYMBOL_GPL (swap_sum_time);
79 EXPORT_SYMBOL_GPL (swap_sum_hit);
82 #define sign_extend(x, signbit) ((x) | (0 - ((x) & (1 << (signbit)))))
83 #define branch_displacement(insn) sign_extend(((insn) & 0xffffff) << 2, 25)
85 static kprobe_opcode_t get_addr_b(kprobe_opcode_t insn, kprobe_opcode_t *addr)
87 // real position less then PC by 8
88 return (kprobe_opcode_t)((long)addr + 8 + branch_displacement(insn));
91 unsigned int arr_traps_template[] = {
92 0xe1a0c00d, // mov ip, sp
93 0xe92dd800, // stmdb sp!, {fp, ip, lr, pc}
94 0xe24cb004, // sub fp, ip, #4 ; 0x4
96 0xe3500000, // cmp r0, #0 ; 0x0
97 0xe89da800, // ldmia sp, {fp, sp, pc}
103 struct kprobe trampoline_p =
105 .addr = (kprobe_opcode_t *) & kretprobe_trampoline,
106 .pre_handler = trampoline_probe_handler
109 // is instruction Thumb2 and NOT a branch, etc...
110 int isThumb2(kprobe_opcode_t insn)
112 if(( (insn & 0xf800) == 0xe800 ||
113 (insn & 0xf800) == 0xf000 ||
114 (insn & 0xf800) == 0xf800)) return 1;
119 int prep_pc_dep_insn_execbuf (kprobe_opcode_t * insns, kprobe_opcode_t insn, int uregs)
127 for (i = 0; i < 13; i++, reg_mask <<= 1)
129 if (!(insn & reg_mask))
135 for (i = 0; i < 13; i++)
137 if ((uregs & 0x1) && (ARM_INSN_REG_RN (insn) == i))
139 if ((uregs & 0x2) && (ARM_INSN_REG_RD (insn) == i))
141 if ((uregs & 0x4) && (ARM_INSN_REG_RS (insn) == i))
143 if ((uregs & 0x8) && (ARM_INSN_REG_RM (insn) == i))
150 DBPRINTF ("there are no free register %x in insn %lx!", uregs, insn);
153 DBPRINTF ("prep_pc_dep_insn_execbuf: using R%d, changing regs %x", i, uregs);
155 // set register to save
156 ARM_INSN_REG_SET_RD (insns[0], i);
157 // set register to load address to
158 ARM_INSN_REG_SET_RD (insns[1], i);
159 // set instruction to execute and patch it
162 ARM_INSN_REG_CLEAR_MR (insn, 15);
163 ARM_INSN_REG_SET_MR (insn, i);
167 if ((uregs & 0x1) && (ARM_INSN_REG_RN (insn) == 15))
168 ARM_INSN_REG_SET_RN (insn, i);
169 if ((uregs & 0x2) && (ARM_INSN_REG_RD (insn) == 15))
170 ARM_INSN_REG_SET_RD (insn, i);
171 if ((uregs & 0x4) && (ARM_INSN_REG_RS (insn) == 15))
172 ARM_INSN_REG_SET_RS (insn, i);
173 if ((uregs & 0x8) && (ARM_INSN_REG_RM (insn) == 15))
174 ARM_INSN_REG_SET_RM (insn, i);
176 insns[UPROBES_TRAMP_INSN_IDX] = insn;
177 // set register to restore
178 ARM_INSN_REG_SET_RD (insns[3], i);
184 int prep_pc_dep_insn_execbuf_thumb (kprobe_opcode_t * insns, kprobe_opcode_t insn, int uregs)
186 unsigned char mreg = 0;
187 unsigned char reg = 0;
190 if (THUMB_INSN_MATCH (APC, insn) || THUMB_INSN_MATCH (LRO3, insn))
192 reg = ((insn & 0xffff) & uregs) >> 8;
194 if (THUMB_INSN_MATCH (MOV3, insn))
196 if (((((unsigned char) insn) & 0xff) >> 3) == 15)
197 reg = (insn & 0xffff) & uregs;
201 if (THUMB2_INSN_MATCH (ADR, insn))
203 reg = ((insn >> 16) & uregs) >> 8;
204 if (reg == 15) return 0;
206 if (THUMB2_INSN_MATCH (LDRW, insn) || THUMB2_INSN_MATCH (LDRW1, insn) ||
207 THUMB2_INSN_MATCH (LDRHW, insn) || THUMB2_INSN_MATCH (LDRHW1, insn) ||
208 THUMB2_INSN_MATCH (LDRWL, insn))
210 reg = ((insn >> 16) & uregs) >> 12;
211 if (reg == 15) return 0;
213 // LDRB.W PC, [PC, #immed] => PLD [PC, #immed], so Rt == PC is skipped
214 if (THUMB2_INSN_MATCH (LDRBW, insn) || THUMB2_INSN_MATCH (LDRBW1, insn) || THUMB2_INSN_MATCH (LDREX, insn))
216 reg = ((insn >> 16) & uregs) >> 12;
218 if (THUMB2_INSN_MATCH (DP, insn))
220 reg = ((insn >> 16) & uregs) >> 12;
221 if (reg == 15) return 0;
223 if (THUMB2_INSN_MATCH (RSBW, insn))
225 reg = ((insn >> 12) & uregs) >> 8;
226 if (reg == 15) return 0;
228 if (THUMB2_INSN_MATCH (RORW, insn))
230 reg = ((insn >> 12) & uregs) >> 8;
231 if (reg == 15) return 0;
233 if (THUMB2_INSN_MATCH (ROR, insn) || THUMB2_INSN_MATCH (LSLW1, insn) || THUMB2_INSN_MATCH (LSLW2, insn) || THUMB2_INSN_MATCH (LSRW1, insn) || THUMB2_INSN_MATCH (LSRW2, insn))
235 reg = ((insn >> 12) & uregs) >> 8;
236 if (reg == 15) return 0;
238 if (THUMB2_INSN_MATCH (TEQ1, insn) || THUMB2_INSN_MATCH (TST1, insn))
242 if (THUMB2_INSN_MATCH (TEQ2, insn) || THUMB2_INSN_MATCH (TST2, insn))
244 reg = THUMB2_INSN_REG_RM(insn);
257 if (( THUMB2_INSN_MATCH (STRW, insn) || THUMB2_INSN_MATCH (STRBW, insn) || THUMB2_INSN_MATCH (STRD, insn) || \
258 THUMB2_INSN_MATCH (STRHT, insn) || THUMB2_INSN_MATCH (STRT, insn) || THUMB2_INSN_MATCH (STRHW1, insn) || \
259 THUMB2_INSN_MATCH (STRHW, insn)) && THUMB2_INSN_REG_RT(insn) == 15)
261 reg = THUMB2_INSN_REG_RT(insn);
264 if (reg == 6 || reg == 7)
266 *((unsigned short*)insns + 0) = (*((unsigned short*)insns + 0) & 0x00ff) | ((1 << mreg) | (1 << (mreg + 1)));
267 *((unsigned short*)insns + 1) = (*((unsigned short*)insns + 1) & 0xf8ff) | (mreg << 8);
268 *((unsigned short*)insns + 2) = (*((unsigned short*)insns + 2) & 0xfff8) | (mreg + 1);
269 *((unsigned short*)insns + 3) = (*((unsigned short*)insns + 3) & 0xffc7) | (mreg << 3);
270 *((unsigned short*)insns + 7) = (*((unsigned short*)insns + 7) & 0xf8ff) | (mreg << 8);
271 *((unsigned short*)insns + 8) = (*((unsigned short*)insns + 8) & 0xffc7) | (mreg << 3);
272 *((unsigned short*)insns + 9) = (*((unsigned short*)insns + 9) & 0xffc7) | ((mreg + 1) << 3);
273 *((unsigned short*)insns + 10) = (*((unsigned short*)insns + 10) & 0x00ff) | (( 1 << mreg) | (1 << (mreg + 1)));
277 if (THUMB_INSN_MATCH (APC, insn))
279 // ADD Rd, PC, #immed_8*4 -> ADD Rd, SP, #immed_8*4
280 *((unsigned short*)insns + 4) = ((insn & 0xffff) | 0x800); // ADD Rd, SP, #immed_8*4
282 if (THUMB_INSN_MATCH (LRO3, insn))
284 // LDR Rd, [PC, #immed_8*4] -> LDR Rd, [SP, #immed_8*4]
285 *((unsigned short*)insns + 4) = ((insn & 0xffff) + 0x5000); // LDR Rd, [SP, #immed_8*4]
287 if (THUMB_INSN_MATCH (MOV3, insn))
289 // MOV Rd, PC -> MOV Rd, SP
290 *((unsigned short*)insns + 4) = ((insn & 0xffff) ^ 0x10); // MOV Rd, SP
292 if (THUMB2_INSN_MATCH (ADR, insn))
294 // ADDW Rd, PC, #imm -> ADDW Rd, SP, #imm
295 insns[2] = (insn & 0xfffffff0) | 0x0d; // ADDW Rd, SP, #imm
297 if (THUMB2_INSN_MATCH (LDRW, insn) || THUMB2_INSN_MATCH (LDRBW, insn) ||
298 THUMB2_INSN_MATCH (LDRHW, insn))
300 // LDR.W Rt, [PC, #-<imm_12>] -> LDR.W Rt, [SP, #-<imm_8>]
301 // !!!!!!!!!!!!!!!!!!!!!!!!
302 // !!! imm_12 vs. imm_8 !!!
303 // !!!!!!!!!!!!!!!!!!!!!!!!
304 insns[2] = (insn & 0xf0fffff0) | 0x0c00000d; // LDR.W Rt, [SP, #-<imm_8>]
306 if (THUMB2_INSN_MATCH (LDRW1, insn) || THUMB2_INSN_MATCH (LDRBW1, insn) ||
307 THUMB2_INSN_MATCH (LDRHW1, insn) || THUMB2_INSN_MATCH (LDRD, insn) || THUMB2_INSN_MATCH (LDRD1, insn) ||
308 THUMB2_INSN_MATCH (LDREX, insn))
310 // LDRx.W Rt, [PC, #+<imm_12>] -> LDRx.W Rt, [SP, #+<imm_12>] (+/-imm_8 for LDRD Rt, Rt2, [PC, #<imm_8>]
311 insns[2] = (insn & 0xfffffff0) | 0xd; // LDRx.W Rt, [SP, #+<imm_12>]
313 if (THUMB2_INSN_MATCH (MUL, insn))
315 insns[2] = (insn & 0xfff0ffff) | 0x000d0000; // MUL Rd, Rn, SP
316 }else{ if (THUMB2_INSN_MATCH (DP, insn))
318 if (THUMB2_INSN_REG_RM(insn) == 15) insns[2] = (insn & 0xfff0ffff) | 0x000d0000; // DP Rd, Rn, PC
319 else if (THUMB2_INSN_REG_RN(insn) == 15) insns[2] = (insn & 0xfffffff0) | 0xd; // DP Rd, PC, Rm
320 }else{ if (THUMB2_INSN_MATCH (LDRWL, insn))
322 // LDRx.W Rt, [PC, #<imm_12>] -> LDRx.W Rt, [SP, #+<imm_12>] (+/-imm_8 for LDRD Rt, Rt2, [PC, #<imm_8>]
323 insns[2] = (insn & 0xfffffff0) | 0xd; // LDRx.W Rt, [SP, #+<imm_12>]
324 }else{ if (THUMB2_INSN_MATCH (RSBW, insn))
326 insns[2] = (insn & 0xfffffff0) | 0xd; // RSB{S}.W Rd, PC, #<const> -> RSB{S}.W Rd, SP, #<const>
327 }else{ if (THUMB2_INSN_MATCH (RORW, insn) || THUMB2_INSN_MATCH (LSLW1, insn) || THUMB2_INSN_MATCH (LSRW1, insn))
329 if ((THUMB2_INSN_REG_RM(insn) == 15) && (THUMB2_INSN_REG_RN(insn) == 15))
331 insns[2] = (insn & 0xfffdfffd); // ROR.W Rd, PC, PC
332 }else if (THUMB2_INSN_REG_RM(insn) == 15) insns[2] = (insn & 0xfff0ffff) | 0xd0000; // ROR.W Rd, Rn, PC
333 else if (THUMB2_INSN_REG_RN(insn) == 15) insns[2] = (insn & 0xfffffff0) | 0xd; // ROR.W Rd, PC, Rm
334 }else{ if (THUMB2_INSN_MATCH (ROR, insn) || THUMB2_INSN_MATCH (LSLW2, insn) || THUMB2_INSN_MATCH (LSRW2, insn))
336 insns[2] = (insn & 0xfff0ffff) | 0xd0000; // ROR{S} Rd, PC, #<const> -> ROR{S} Rd, SP, #<const>
350 if (THUMB2_INSN_MATCH (STRW, insn) || THUMB2_INSN_MATCH (STRBW, insn))
352 insns[2] = (insn & 0xfff0ffff) | 0x000d0000; // STRx.W Rt, [Rn, SP]
354 if (THUMB2_INSN_MATCH (STRD, insn) || THUMB2_INSN_MATCH (STRHT, insn) || THUMB2_INSN_MATCH (STRT, insn) || THUMB2_INSN_MATCH (STRHW1, insn))
356 if (THUMB2_INSN_REG_RN(insn) == 15)
358 insns[2] = (insn & 0xfffffff0) | 0xd; // STRD/T/HT{.W} Rt, [SP, ...]
363 if (THUMB2_INSN_MATCH (STRHW, insn) && (THUMB2_INSN_REG_RN(insn) == 15))
365 if (THUMB2_INSN_REG_RN(insn) == 15)
367 insns[2] = (insn & 0xf0fffff0) | 0x0c00000d; // STRH.W Rt, [SP, #-<imm_8>]
376 if ((reg == 15) && (THUMB2_INSN_MATCH (STRW, insn) || \
377 THUMB2_INSN_MATCH (STRBW, insn) || \
378 THUMB2_INSN_MATCH (STRD, insn) || \
379 THUMB2_INSN_MATCH (STRHT, insn) || \
380 THUMB2_INSN_MATCH (STRT, insn) || \
381 THUMB2_INSN_MATCH (STRHW1, insn) || \
382 THUMB2_INSN_MATCH (STRHW, insn) ))
384 insns[2] = (insns[2] & 0x0fffffff) | 0xd0000000;
389 if (THUMB2_INSN_MATCH (TEQ1, insn) || THUMB2_INSN_MATCH (TST1, insn))
391 insns[2] = (insn & 0xfffffff0) | 0xd; // TEQ SP, #<const>
392 }else{ if (THUMB2_INSN_MATCH (TEQ2, insn) || THUMB2_INSN_MATCH (TST2, insn))
394 if ((THUMB2_INSN_REG_RN(insn) == 15) && (THUMB2_INSN_REG_RM(insn) == 15))
396 insns[2] = (insn & 0xfffdfffd); // TEQ/TST PC, PC
397 }else if (THUMB2_INSN_REG_RM(insn) == 15) insns[2] = (insn & 0xfff0ffff) | 0xd0000; // TEQ/TST Rn, PC
398 else if (THUMB2_INSN_REG_RN(insn) == 15) insns[2] = (insn & 0xfffffff0) | 0xd; // TEQ/TST PC, Rm
407 int arch_check_insn_arm (struct arch_specific_insn *ainsn)
411 // check instructions that can change PC by nature
413 // ARM_INSN_MATCH (UNDEF, ainsn->insn_arm[0]) ||
414 ARM_INSN_MATCH (AUNDEF, ainsn->insn_arm[0]) ||
415 ARM_INSN_MATCH (SWI, ainsn->insn_arm[0]) ||
416 ARM_INSN_MATCH (BREAK, ainsn->insn_arm[0]) ||
417 ARM_INSN_MATCH (BL, ainsn->insn_arm[0]) ||
418 ARM_INSN_MATCH (BLX1, ainsn->insn_arm[0]) ||
419 ARM_INSN_MATCH (BLX2, ainsn->insn_arm[0]) ||
420 ARM_INSN_MATCH (BX, ainsn->insn_arm[0]) ||
421 ARM_INSN_MATCH (BXJ, ainsn->insn_arm[0]))
423 DBPRINTF ("Bad insn arch_check_insn_arm: %lx\n", ainsn->insn_arm[0]);
426 #ifndef CONFIG_CPU_V7
427 // check instructions that can write result to PC
428 else if ((ARM_INSN_MATCH (DPIS, ainsn->insn_arm[0]) ||
429 ARM_INSN_MATCH (DPRS, ainsn->insn_arm[0]) ||
430 ARM_INSN_MATCH (DPI, ainsn->insn_arm[0]) ||
431 ARM_INSN_MATCH (LIO, ainsn->insn_arm[0]) ||
432 ARM_INSN_MATCH (LRO, ainsn->insn_arm[0])) &&
433 (ARM_INSN_REG_RD (ainsn->insn_arm[0]) == 15))
435 DBPRINTF ("Bad arch_check_insn_arm: %lx\n", ainsn->insn_arm[0]);
438 #endif // CONFIG_CPU_V7
439 // check special instruction loads store multiple registers
440 else if ((ARM_INSN_MATCH (LM, ainsn->insn_arm[0]) || ARM_INSN_MATCH (SM, ainsn->insn_arm[0])) &&
441 // store pc or load to pc
442 (ARM_INSN_REG_MR (ainsn->insn_arm[0], 15) ||
443 // store/load with pc update
444 ((ARM_INSN_REG_RN (ainsn->insn_arm[0]) == 15) && (ainsn->insn_arm[0] & 0x200000))))
446 DBPRINTF ("Bad insn arch_check_insn_arm: %lx\n", ainsn->insn_arm[0]);
452 int arch_check_insn_thumb (struct arch_specific_insn *ainsn)
456 // check instructions that can change PC
457 if ( THUMB_INSN_MATCH (UNDEF, ainsn->insn_thumb[0]) ||
458 THUMB_INSN_MATCH (SWI, ainsn->insn_thumb[0]) ||
459 THUMB_INSN_MATCH (BREAK, ainsn->insn_thumb[0]) ||
460 THUMB2_INSN_MATCH (BL, ainsn->insn_thumb[0]) ||
461 THUMB_INSN_MATCH (B1, ainsn->insn_thumb[0]) ||
462 THUMB_INSN_MATCH (B2, ainsn->insn_thumb[0]) ||
463 THUMB2_INSN_MATCH (B1, ainsn->insn_thumb[0]) ||
464 THUMB2_INSN_MATCH (B2, ainsn->insn_thumb[0]) ||
465 THUMB2_INSN_MATCH (BLX1, ainsn->insn_thumb[0]) ||
466 THUMB_INSN_MATCH (BLX2, ainsn->insn_thumb[0]) ||
467 THUMB_INSN_MATCH (BX, ainsn->insn_thumb[0]) ||
468 THUMB2_INSN_MATCH (BXJ, ainsn->insn_thumb[0]) ||
469 (THUMB2_INSN_MATCH (ADR, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RD(ainsn->insn_thumb[0]) == 15) ||
470 (THUMB2_INSN_MATCH (LDRW, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RT(ainsn->insn_thumb[0]) == 15) ||
471 (THUMB2_INSN_MATCH (LDRW1, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RT(ainsn->insn_thumb[0]) == 15) ||
472 (THUMB2_INSN_MATCH (LDRHW, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RT(ainsn->insn_thumb[0]) == 15) ||
473 (THUMB2_INSN_MATCH (LDRHW1, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RT(ainsn->insn_thumb[0]) == 15) ||
474 (THUMB2_INSN_MATCH (LDRWL, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RT(ainsn->insn_thumb[0]) == 15) ||
475 THUMB2_INSN_MATCH (LDMIA, ainsn->insn_thumb[0]) ||
476 THUMB2_INSN_MATCH (LDMDB, ainsn->insn_thumb[0]) ||
477 (THUMB2_INSN_MATCH (DP, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RD(ainsn->insn_thumb[0]) == 15) ||
478 (THUMB2_INSN_MATCH (RSBW, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RD(ainsn->insn_thumb[0]) == 15) ||
479 (THUMB2_INSN_MATCH (RORW, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RD(ainsn->insn_thumb[0]) == 15) ||
480 (THUMB2_INSN_MATCH (ROR, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RD(ainsn->insn_thumb[0]) == 15) ||
481 (THUMB2_INSN_MATCH (LSLW1, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RD(ainsn->insn_thumb[0]) == 15) ||
482 (THUMB2_INSN_MATCH (LSLW2, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RD(ainsn->insn_thumb[0]) == 15) ||
483 (THUMB2_INSN_MATCH (LSRW1, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RD(ainsn->insn_thumb[0]) == 15) ||
484 (THUMB2_INSN_MATCH (LSRW2, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RD(ainsn->insn_thumb[0]) == 15) ||
485 /* skip PC, #-imm12 -> SP, #-imm8 and Tegra-hanging instructions */
486 (THUMB2_INSN_MATCH (STRW1, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RN(ainsn->insn_thumb[0]) == 15) ||
487 (THUMB2_INSN_MATCH (STRBW1, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RN(ainsn->insn_thumb[0]) == 15) ||
488 (THUMB2_INSN_MATCH (STRHW1, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RN(ainsn->insn_thumb[0]) == 15) ||
489 (THUMB2_INSN_MATCH (STRW, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RN(ainsn->insn_thumb[0]) == 15) ||
490 (THUMB2_INSN_MATCH (STRHW, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RN(ainsn->insn_thumb[0]) == 15) ||
491 (THUMB2_INSN_MATCH (LDRW, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RN(ainsn->insn_thumb[0]) == 15) ||
492 (THUMB2_INSN_MATCH (LDRBW, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RN(ainsn->insn_thumb[0]) == 15) ||
493 (THUMB2_INSN_MATCH (LDRHW, ainsn->insn_thumb[0]) && THUMB2_INSN_REG_RN(ainsn->insn_thumb[0]) == 15) ||
494 /* skip STRDx/LDRDx Rt, Rt2, [Rd, ...] */
495 (THUMB2_INSN_MATCH (LDRD, ainsn->insn_thumb[0]) || THUMB2_INSN_MATCH (LDRD1, ainsn->insn_thumb[0]) || THUMB2_INSN_MATCH (STRD, ainsn->insn_thumb[0])) )
497 DBPRINTF ("Bad insn arch_check_insn_thumb: %lx\n", ainsn->insn_thumb[0]);
504 int arch_prepare_kretprobe (struct kretprobe *p)
506 DBPRINTF("Warrning: arch_prepare_kretprobe is not implemented\n");
510 int arch_prepare_kprobe (struct kprobe *p)
512 kprobe_opcode_t insns[KPROBES_TRAMP_LEN];
513 int uregs, pc_dep, ret = 0;
514 kprobe_opcode_t insn[MAX_INSN_SIZE];
515 struct arch_specific_insn ainsn;
517 /* insn: must be on special executable page on i386. */
518 p->ainsn.insn = get_insn_slot (NULL, 0);
522 memcpy (insn, p->addr, MAX_INSN_SIZE * sizeof (kprobe_opcode_t));
523 ainsn.insn_arm = ainsn.insn = insn;
524 ret = arch_check_insn_arm (&ainsn);
527 p->opcode = *p->addr;
531 if(ARM_INSN_MATCH (DPIS, insn[0]) || ARM_INSN_MATCH (LRO, insn[0]) ||
532 ARM_INSN_MATCH (SRO, insn[0]))
535 if( (ARM_INSN_REG_RN (insn[0]) == 15) || (ARM_INSN_REG_RM (insn[0]) == 15) ||
536 (ARM_INSN_MATCH (SRO, insn[0]) && (ARM_INSN_REG_RD (insn[0]) == 15)) )
538 DBPRINTF ("Unboostable insn %lx, DPIS/LRO/SRO\n", insn[0]);
543 else if(ARM_INSN_MATCH (DPI, insn[0]) || ARM_INSN_MATCH (LIO, insn[0]) ||
544 ARM_INSN_MATCH (SIO, insn[0]))
547 if ((ARM_INSN_REG_RN (insn[0]) == 15) || (ARM_INSN_MATCH (SIO, insn[0]) &&
548 (ARM_INSN_REG_RD (insn[0]) == 15)))
551 DBPRINTF ("Unboostable insn %lx/%p, DPI/LIO/SIO\n", insn[0], p);
555 else if(ARM_INSN_MATCH (DPRS, insn[0]))
558 if ((ARM_INSN_REG_RN (insn[0]) == 15) || (ARM_INSN_REG_RM (insn[0]) == 15) ||
559 (ARM_INSN_REG_RS (insn[0]) == 15))
562 DBPRINTF ("Unboostable insn %lx, DPRS\n", insn[0]);
566 else if(ARM_INSN_MATCH (SM, insn[0]))
569 if (ARM_INSN_REG_MR (insn[0], 15))
571 DBPRINTF ("Unboostable insn %lx, SM\n", insn[0]);
575 // check instructions that can write result to SP andu uses PC
576 if (pc_dep && (ARM_INSN_REG_RD (ainsn.insn[0]) == 13))
578 free_insn_slot(&kprobe_insn_pages, NULL, p->ainsn.insn);
585 memcpy (insns, pc_dep_insn_execbuf, sizeof (insns));
586 if (prep_pc_dep_insn_execbuf (insns, insn[0], uregs) != 0)
588 DBPRINTF ("failed to prepare exec buffer for insn %lx!", insn[0]);
589 free_insn_slot(&kprobe_insn_pages, NULL, p->ainsn.insn);
592 insns[6] = (kprobe_opcode_t) (p->addr + 2);
596 memcpy (insns, gen_insn_execbuf, sizeof (insns));
597 insns[KPROBES_TRAMP_INSN_IDX] = insn[0];
599 insns[7] = (kprobe_opcode_t) (p->addr + 1);
600 DBPRINTF ("arch_prepare_kprobe: insn %lx", insn[0]);
601 DBPRINTF ("arch_prepare_kprobe: to %p - %lx %lx %lx %lx %lx %lx %lx %lx %lx",
602 p->ainsn.insn, insns[0], insns[1], insns[2], insns[3], insns[4],
603 insns[5], insns[6], insns[7], insns[8]);
604 memcpy (p->ainsn.insn, insns, sizeof(insns));
605 flush_icache_range((long unsigned)p->ainsn.insn, (long unsigned)(p->ainsn.insn) + sizeof(insns));
613 free_insn_slot(&kprobe_insn_pages, NULL, p->ainsn.insn);
614 printk("arch_prepare_kprobe: instruction 0x%lx not instrumentation, addr=0x%p\n", insn[0], p->addr);
620 static unsigned int arch_construct_brunch (unsigned int base, unsigned int addr, int link)
622 kprobe_opcode_t insn;
623 unsigned int bpi = (unsigned int) base - (unsigned int) addr - 8;
626 DBPRINTF ("base=%x addr=%x base-addr-8=%x\n", base, addr, bpi);
627 if (abs (insn & 0xffffff) > 0xffffff)
629 DBPRINTF ("ERROR: kprobe address out of range\n");
632 insn = insn & 0xffffff;
633 insn = insn | ((link != 0) ? 0xeb000000 : 0xea000000);
634 DBPRINTF ("insn=%lX\n", insn);
635 return (unsigned int) insn;
639 int arch_copy_trampoline_arm_uprobe (struct kprobe *p, struct task_struct *task, int atomic);
640 int arch_copy_trampoline_thumb_uprobe (struct kprobe *p, struct task_struct *task, int atomic);
642 int arch_prepare_uprobe (struct kprobe *p, struct task_struct *task, int atomic)
645 kprobe_opcode_t insn[MAX_INSN_SIZE];
647 if ((unsigned long) p->addr & 0x01)
649 printk("Error in %s at %d: attempt to register kprobe at an unaligned address\n", __FILE__, __LINE__);
652 if (!read_proc_vm_atomic (task, (unsigned long) p->addr, &insn, MAX_INSN_SIZE * sizeof(kprobe_opcode_t)))
653 panic ("Failed to read memory %p!\n", p->addr);
655 p->ainsn.insn_arm = get_insn_slot(task, atomic);
656 if (!p->ainsn.insn_arm) {
657 printk("Error in %s at %d: kprobe slot allocation error (arm)\n", __FILE__, __LINE__);
660 ret = arch_copy_trampoline_arm_uprobe(p, task, 1);
662 free_insn_slot(&uprobe_insn_pages, task, p->ainsn.insn_arm);
665 p->ainsn.insn_thumb = get_insn_slot(task, atomic);
666 if (!p->ainsn.insn_thumb) {
667 printk("Error in %s at %d: kprobe slot allocation error (thumb)\n", __FILE__, __LINE__);
670 ret = arch_copy_trampoline_thumb_uprobe(p, task, 1);
672 free_insn_slot(&uprobe_insn_pages, task, p->ainsn.insn_arm);
673 free_insn_slot(&uprobe_insn_pages, task, p->ainsn.insn_thumb);
676 if ((p->safe_arm == -1) && (p->safe_thumb == -1)) {
677 printk("Error in %s at %d: failed arch_copy_trampoline_*_uprobe() (both) [tgid=%u, addr=%x, data=%x]\n",
678 __FILE__, __LINE__, task->tgid, p->addr, p->opcode);
679 if (!write_proc_vm_atomic (task, (unsigned long) p->addr, &p->opcode, sizeof (p->opcode)))
680 panic ("Failed to write memory %p!\n", p->addr);
681 free_insn_slot(&uprobe_insn_pages, task, p->ainsn.insn_arm);
682 free_insn_slot(&uprobe_insn_pages, task, p->ainsn.insn_thumb);
688 int arch_prepare_uretprobe (struct kretprobe *p, struct task_struct *task)
690 DBPRINTF("Warrning: arch_prepare_uretprobe is not implemented\n");
694 void prepare_singlestep (struct kprobe *p, struct pt_regs *regs)
697 regs->ARM_pc = (unsigned long)p->ss_addr;
700 regs->ARM_pc = (unsigned long)p->ainsn.insn;
704 void save_previous_kprobe(struct kprobe_ctlblk *kcb, struct kprobe *p_run)
707 panic("arm_save_previous_kprobe: p_run == NULL\n");
710 if (kcb->prev_kprobe.kp != NULL) {
711 DBPRINTF ("no space to save new probe[]: task = %d/%s", current->pid, current->comm);
714 kcb->prev_kprobe.kp = p_run;
715 kcb->prev_kprobe.status = kcb->kprobe_status;
718 void restore_previous_kprobe(struct kprobe_ctlblk *kcb)
720 set_current_kprobe(kcb->prev_kprobe.kp, NULL, NULL);
721 kcb->kprobe_status = kcb->prev_kprobe.status;
722 kcb->prev_kprobe.kp = NULL;
723 kcb->prev_kprobe.status = 0;
726 void set_current_kprobe(struct kprobe *p, struct pt_regs *regs, struct kprobe_ctlblk *kcb)
728 __get_cpu_var(current_kprobe) = p;
729 DBPRINTF ("set_current_kprobe: p=%p addr=%p\n", p, p->addr);
732 int arch_copy_trampoline_arm_uprobe (struct kprobe *p, struct task_struct *task, int atomic)
734 kprobe_opcode_t insns[UPROBES_TRAMP_LEN];
736 kprobe_opcode_t insn[MAX_INSN_SIZE];
737 struct arch_specific_insn ainsn;
740 if ((unsigned long) p->addr & 0x01)
742 printk("Error in %s at %d: attempt to register kprobe at an unaligned address\n", __FILE__, __LINE__);
746 ainsn.insn_arm = insn;
747 if (!arch_check_insn_arm(&ainsn))
753 if (ARM_INSN_MATCH (DPIS, insn[0]) || ARM_INSN_MATCH (LRO, insn[0]) ||
754 ARM_INSN_MATCH (SRO, insn[0]))
757 if ((ARM_INSN_REG_RN (insn[0]) == 15) || (ARM_INSN_REG_RM (insn[0]) == 15) ||
758 (ARM_INSN_MATCH (SRO, insn[0]) && (ARM_INSN_REG_RD (insn[0]) == 15)))
760 DBPRINTF ("Unboostable insn %lx, DPIS/LRO/SRO\n", insn[0]);
765 else if (ARM_INSN_MATCH (DPI, insn[0]) || ARM_INSN_MATCH (LIO, insn[0]) ||
766 ARM_INSN_MATCH (SIO, insn[0]))
769 if ((ARM_INSN_REG_RN (insn[0]) == 15) || (ARM_INSN_MATCH (SIO, insn[0]) &&
770 (ARM_INSN_REG_RD (insn[0]) == 15)))
773 DBPRINTF ("Unboostable insn %lx/%p, DPI/LIO/SIO\n", insn[0], p);
777 else if (ARM_INSN_MATCH (DPRS, insn[0]))
780 if ((ARM_INSN_REG_RN (insn[0]) == 15) || (ARM_INSN_REG_RM (insn[0]) == 15) ||
781 (ARM_INSN_REG_RS (insn[0]) == 15))
784 DBPRINTF ("Unboostable insn %lx, DPRS\n", insn[0]);
788 else if (ARM_INSN_MATCH (SM, insn[0]))
791 if (ARM_INSN_REG_MR (insn[0], 15))
793 DBPRINTF ("Unboostable insn %lx, SM\n", insn[0]);
797 // check instructions that can write result to SP andu uses PC
798 if (pc_dep && (ARM_INSN_REG_RD (ainsn.insn_arm[0]) == 13))
800 printk("Error in %s at %d: instruction check failed (arm)\n", __FILE__, __LINE__);
802 // TODO: move free to later phase
803 //free_insn_slot (&uprobe_insn_pages, task, p->ainsn.insn_arm, 0);
806 if (unlikely(uregs && pc_dep))
808 memcpy (insns, pc_dep_insn_execbuf, sizeof (insns));
809 if (prep_pc_dep_insn_execbuf (insns, insn[0], uregs) != 0)
811 printk("Error in %s at %d: failed to prepare exec buffer for insn %lx!",
812 __FILE__, __LINE__, insn[0]);
814 // TODO: move free to later phase
815 //free_insn_slot (&uprobe_insn_pages, task, p->ainsn.insn_arm, 0);
818 //insns[UPROBES_TRAMP_SS_BREAK_IDX] = BREAKPOINT_INSTRUCTION;
819 insns[6] = (kprobe_opcode_t) (p->addr + 2);
823 memcpy (insns, gen_insn_execbuf, sizeof (insns));
824 insns[UPROBES_TRAMP_INSN_IDX] = insn[0];
826 insns[UPROBES_TRAMP_RET_BREAK_IDX] = BREAKPOINT_INSTRUCTION;
827 insns[7] = (kprobe_opcode_t) (p->addr + 1);
830 if(ARM_INSN_MATCH (B, ainsn.insn_arm[0]))
832 memcpy (insns, pc_dep_insn_execbuf, sizeof (insns));
833 insns[UPROBES_TRAMP_RET_BREAK_IDX] = BREAKPOINT_INSTRUCTION;
834 insns[6] = (kprobe_opcode_t) (p->addr + 2);
835 insns[7] = get_addr_b(p->opcode, p->addr);
838 DBPRINTF ("arch_prepare_uprobe: to %p - %lx %lx %lx %lx %lx %lx %lx %lx %lx",
839 p->ainsn.insn_arm, insns[0], insns[1], insns[2], insns[3], insns[4],
840 insns[5], insns[6], insns[7], insns[8]);
841 if (!write_proc_vm_atomic (task, (unsigned long) p->ainsn.insn_arm, insns, sizeof (insns)))
843 panic("failed to write memory %p!\n", p->ainsn.insn);
844 // Mr_Nobody: we have to panic, really??...
845 //free_insn_slot (&uprobe_insn_pages, task, p->ainsn.insn_arm, 0);
851 int arch_copy_trampoline_thumb_uprobe (struct kprobe *p, struct task_struct *task, int atomic)
855 kprobe_opcode_t insn[MAX_INSN_SIZE];
856 struct arch_specific_insn ainsn;
857 kprobe_opcode_t insns[UPROBES_TRAMP_LEN * 2];
860 if ((unsigned long) p->addr & 0x01)
862 printk("Error in %s at %d: attempt to register kprobe at an unaligned address\n", __FILE__, __LINE__);
866 ainsn.insn_thumb = insn;
867 if (!arch_check_insn_thumb(&ainsn))
873 if (THUMB_INSN_MATCH (APC, insn[0]) || THUMB_INSN_MATCH (LRO3, insn[0]))
875 uregs = 0x0700; // 8-10
878 else if (THUMB_INSN_MATCH (MOV3, insn[0]) && (((((unsigned char) insn[0]) & 0xff) >> 3) == 15))
884 else if THUMB2_INSN_MATCH (ADR, insn[0])
886 uregs = 0x0f00; // Rd 8-11
889 else if (((THUMB2_INSN_MATCH (LDRW, insn[0]) || THUMB2_INSN_MATCH (LDRW1, insn[0]) ||
890 THUMB2_INSN_MATCH (LDRBW, insn[0]) || THUMB2_INSN_MATCH (LDRBW1, insn[0]) ||
891 THUMB2_INSN_MATCH (LDRHW, insn[0]) || THUMB2_INSN_MATCH (LDRHW1, insn[0]) ||
892 THUMB2_INSN_MATCH (LDRWL, insn[0])) && THUMB2_INSN_REG_RN(insn[0]) == 15) ||
893 THUMB2_INSN_MATCH (LDREX, insn[0]) ||
894 ((THUMB2_INSN_MATCH (STRW, insn[0]) || THUMB2_INSN_MATCH (STRBW, insn[0]) ||
895 THUMB2_INSN_MATCH (STRHW, insn[0]) || THUMB2_INSN_MATCH (STRHW1, insn[0])) &&
896 (THUMB2_INSN_REG_RN(insn[0]) == 15 || THUMB2_INSN_REG_RT(insn[0]) == 15)) ||
897 ((THUMB2_INSN_MATCH (STRT, insn[0]) || THUMB2_INSN_MATCH (STRHT, insn[0])) &&
898 (THUMB2_INSN_REG_RN(insn[0]) == 15 || THUMB2_INSN_REG_RT(insn[0]) == 15)) )
900 uregs = 0xf000; // Rt 12-15
903 else if ((THUMB2_INSN_MATCH (LDRD, insn[0]) || THUMB2_INSN_MATCH (LDRD1, insn[0])) && (THUMB2_INSN_REG_RN(insn[0]) == 15))
905 uregs = 0xff00; // Rt 12-15, Rt2 8-11
908 else if (THUMB2_INSN_MATCH (MUL, insn[0]) && THUMB2_INSN_REG_RM(insn[0]) == 15)
913 else if (THUMB2_INSN_MATCH (DP, insn[0]) && (THUMB2_INSN_REG_RN(insn[0]) == 15 || THUMB2_INSN_REG_RM(insn[0]) == 15))
915 uregs = 0xf000; // Rd 12-15
918 else if (THUMB2_INSN_MATCH(STRD, insn[0]) && ((THUMB2_INSN_REG_RN(insn[0]) == 15) || (THUMB2_INSN_REG_RT(insn[0]) == 15) || THUMB2_INSN_REG_RT2(insn[0]) == 15))
920 uregs = 0xff00; // Rt 12-15, Rt2 8-11
923 else if (THUMB2_INSN_MATCH (RSBW, insn[0]) && THUMB2_INSN_REG_RN(insn[0]) == 15)
925 uregs = 0x0f00; // Rd 8-11
928 else if (THUMB2_INSN_MATCH (RORW, insn[0]) && (THUMB2_INSN_REG_RN(insn[0]) == 15 || THUMB2_INSN_REG_RM(insn[0]) == 15))
933 else if ((THUMB2_INSN_MATCH (ROR, insn[0]) || THUMB2_INSN_MATCH(LSLW2, insn[0]) || THUMB2_INSN_MATCH(LSRW2, insn[0])) && THUMB2_INSN_REG_RM(insn[0]) == 15)
935 uregs = 0x0f00; // Rd 8-11
938 else if ((THUMB2_INSN_MATCH (LSLW1, insn[0]) || THUMB2_INSN_MATCH (LSRW1, insn[0])) && (THUMB2_INSN_REG_RN(insn[0]) == 15 || THUMB2_INSN_REG_RM(insn[0]) == 15))
940 uregs = 0x0f00; // Rd 8-11
943 else if ((THUMB2_INSN_MATCH (TEQ1, insn[0]) || THUMB2_INSN_MATCH (TST1, insn[0])) && THUMB2_INSN_REG_RN(insn[0]) == 15)
945 uregs = 0xf0000; //Rn 0-3 (16-19)
948 else if ((THUMB2_INSN_MATCH (TEQ2, insn[0]) || THUMB2_INSN_MATCH (TST2, insn[0])) &&
949 (THUMB2_INSN_REG_RN(insn[0]) == 15 || THUMB2_INSN_REG_RM(insn[0]) == 15))
951 uregs = 0xf0000; //Rn 0-3 (16-19)
954 if (unlikely(uregs && pc_dep))
956 memcpy (insns, pc_dep_insn_execbuf_thumb, 18 * 2);
957 if (prep_pc_dep_insn_execbuf_thumb (insns, insn[0], uregs) != 0)
959 printk("Error in %s at %d: failed to prepare exec buffer for insn %lx!",
960 __FILE__, __LINE__, insn[0]);
962 //free_insn_slot (&uprobe_insn_pages, task, p->ainsn.insn_thumb, 0);
965 addr = ((unsigned int)p->addr) + 4;
966 *((unsigned short*)insns + 13) = 0xdeff;
967 *((unsigned short*)insns + 14) = addr & 0x0000ffff;
968 *((unsigned short*)insns + 15) = addr >> 16;
969 if (!isThumb2(insn[0]))
971 addr = ((unsigned int)p->addr) + 2;
972 *((unsigned short*)insns + 16) = (addr & 0x0000ffff) | 0x1;
973 *((unsigned short*)insns + 17) = addr >> 16;
976 addr = ((unsigned int)p->addr) + 4;
977 *((unsigned short*)insns + 16) = (addr & 0x0000ffff) | 0x1;
978 *((unsigned short*)insns + 17) = addr >> 16;
982 memcpy (insns, gen_insn_execbuf_thumb, 18 * 2);
983 *((unsigned short*)insns + 13) = 0xdeff;
984 if (!isThumb2(insn[0]))
986 addr = ((unsigned int)p->addr) + 2;
987 *((unsigned short*)insns + 2) = insn[0];
988 *((unsigned short*)insns + 16) = (addr & 0x0000ffff) | 0x1;
989 *((unsigned short*)insns + 17) = addr >> 16;
992 addr = ((unsigned int)p->addr) + 4;
994 *((unsigned short*)insns + 16) = (addr & 0x0000ffff) | 0x1;
995 *((unsigned short*)insns + 17) = addr >> 16;
998 if (!write_proc_vm_atomic (task, (unsigned long) p->ainsn.insn_thumb, insns, 18 * 2))
1000 panic("failed to write memory %p!\n", p->ainsn.insn_thumb);
1001 // Mr_Nobody: we have to panic, really??...
1002 //free_insn_slot (&uprobe_insn_pages, task, p->ainsn.insn_thumb, 0);
1008 static int check_validity_insn(struct kprobe *p, struct pt_regs *regs, struct task_struct *task)
1012 if (unlikely(thumb_mode(regs))) {
1013 if (p->safe_thumb != -1) {
1014 p->ainsn.insn = p->ainsn.insn_thumb;
1015 list_for_each_entry_rcu(kp, &p->list, list) {
1016 kp->ainsn.insn = p->ainsn.insn_thumb;
1019 printk("Error in %s at %d: we are in thumb mode (!) and check instruction was fail \
1020 (%0lX instruction at %p address)!\n", __FILE__, __LINE__, p->opcode, p->addr);
1021 // Test case when we do our actions on already running application
1022 arch_disarm_uprobe(p, task);
1026 if (p->safe_arm != -1) {
1027 p->ainsn.insn = p->ainsn.insn_arm;
1028 list_for_each_entry_rcu(kp, &p->list, list) {
1029 kp->ainsn.insn = p->ainsn.insn_arm;
1032 printk("Error in %s at %d: we are in arm mode (!) and check instruction was fail \
1033 (%0lX instruction at %p address)!\n", __FILE__, __LINE__, p->opcode, p->addr);
1034 // Test case when we do our actions on already running application
1035 arch_disarm_uprobe(p, task);
1043 static int kprobe_trap_handler(struct pt_regs *regs, unsigned int instr)
1046 unsigned long flags;
1047 local_irq_save(flags);
1048 ret = kprobe_handler(regs);
1049 local_irq_restore(flags);
1053 int kprobe_handler(struct pt_regs *regs)
1056 char *msg_out = NULL;
1057 unsigned long user_m = user_mode(regs);
1058 pid_t tgid = (user_m) ? current->tgid : 0;
1059 kprobe_opcode_t *addr = (kprobe_opcode_t *) (regs->ARM_pc);
1061 struct kprobe *p = NULL, *p_run = NULL;
1062 int ret = 0, retprobe = 0, reenter = 0;
1063 kprobe_opcode_t *ssaddr = 0;
1064 struct kprobe_ctlblk *kcb;
1066 #ifdef SUPRESS_BUG_MESSAGES
1067 int swap_oops_in_progress;
1068 // oops_in_progress used to avoid BUG() messages that slow down kprobe_handler() execution
1069 swap_oops_in_progress = oops_in_progress;
1070 oops_in_progress = 1;
1072 #ifdef OVERHEAD_DEBUG
1073 struct timeval swap_tv1;
1074 struct timeval swap_tv2;
1075 #define USEC_IN_SEC_NUM 1000000
1076 do_gettimeofday(&swap_tv1);
1080 // printk("### kprobe_handler: task[tgid=%u (%s)] addr=%p\n", tgid, current->comm, addr);
1081 p = get_kprobe(addr, tgid);
1083 if (user_m && p && (check_validity_insn(p, regs, current) != 0)) {
1084 goto no_kprobe_live;
1087 /* We're in an interrupt, but this is clear and BUG()-safe. */
1088 kcb = get_kprobe_ctlblk ();
1090 /* Check we're not actually recursing */
1091 // TODO: event is not saving in trace
1092 p_run = kprobe_running();
1095 DBPRINTF("lock???");
1098 if (!tgid && (addr == (kprobe_opcode_t *)kretprobe_trampoline)) {
1099 save_previous_kprobe(kcb, p_run);
1100 kcb->kprobe_status = KPROBE_REENTER;
1103 /* We have reentered the kprobe_handler(), since
1104 * another probe was hit while within the handler.
1105 * We here save the original kprobes variables and
1106 * just single step on the instruction of the new probe
1107 * without calling any user handlers.
1109 kprobes_inc_nmissed_count (p);
1110 prepare_singlestep (p, regs);
1116 if(tgid) { //we can reenter probe upon uretprobe exception
1117 DBPRINTF ("check for UNDEF_INSTRUCTION %p\n", addr);
1118 // UNDEF_INSTRUCTION from user space
1120 p = get_kprobe_by_insn_slot(addr, tgid, regs);
1122 save_previous_kprobe(kcb, p_run);
1123 kcb->kprobe_status = KPROBE_REENTER;
1126 DBPRINTF ("uretprobe %p\n", addr);
1131 DBPRINTF ("kprobe_running !!! p = 0x%p p->break_handler = 0x%p", p, p->break_handler);
1132 /*if (p->break_handler && p->break_handler(p, regs)) {
1133 DBPRINTF("kprobe_running !!! goto ss");
1136 DBPRINTF ("unknown uprobe at %p cur at %p/%p\n", addr, p->addr, p->ainsn.insn);
1138 ssaddr = p->ainsn.insn + UPROBES_TRAMP_SS_BREAK_IDX;
1140 ssaddr = p->ainsn.insn + KPROBES_TRAMP_SS_BREAK_IDX;
1141 if (addr == ssaddr) {
1142 regs->ARM_pc = (unsigned long) (p->addr + 1);
1143 DBPRINTF ("finish step at %p cur at %p/%p, redirect to %lx\n", addr, p->addr, p->ainsn.insn, regs->ARM_pc);
1144 if (kcb->kprobe_status == KPROBE_REENTER) {
1145 restore_previous_kprobe(kcb);
1147 reset_current_kprobe();
1150 DBPRINTF ("kprobe_running !!! goto no");
1152 /* If it's not ours, can't be delete race, (we hold lock). */
1153 DBPRINTF ("no_kprobe");
1161 DBPRINTF ("search UNDEF_INSTRUCTION %p\n", addr);
1162 // UNDEF_INSTRUCTION from user space
1164 p = get_kprobe_by_insn_slot(addr, tgid, regs);
1166 /* Not one of ours: let kernel handle it */
1167 DBPRINTF ("no_kprobe");
1171 DBPRINTF ("uretprobe %p\n", addr);
1173 /* Not one of ours: let kernel handle it */
1174 DBPRINTF ("no_kprobe");
1178 // restore opcode for thumb app
1179 if (user_mode( regs ) && thumb_mode( regs )) {
1180 if (!isThumb2(p->opcode)) {
1181 unsigned long tmp = p->opcode >> 16;
1182 write_proc_vm_atomic(current, (unsigned long)((unsigned short*)p->addr + 1), &tmp, 2);
1184 unsigned long tmp = p->opcode;
1185 write_proc_vm_atomic(current, (unsigned long)((unsigned short*)p->addr), &tmp, 4);
1187 flush_icache_range ((unsigned int) p->addr, (unsigned int) (((unsigned int) p->addr) + (sizeof (kprobe_opcode_t) * 2)));
1189 set_current_kprobe(p, NULL, NULL);
1191 kcb->kprobe_status = KPROBE_HIT_ACTIVE;
1192 if (retprobe) { //(einsn == UNDEF_INSTRUCTION)
1193 ret = trampoline_probe_handler (p, regs);
1194 } else if (p->pre_handler) {
1195 ret = p->pre_handler (p, regs);
1196 if(p->pre_handler != trampoline_probe_handler) {
1197 reset_current_kprobe();
1202 /* handler has already set things up, so skip ss setup */
1208 msg_out = "no_kprobe\n";
1209 err_out = 1; // return with death
1213 msg_out = "no_kprobe live\n";
1214 err_out = 0; // ok - life is life
1218 preempt_enable_no_resched();
1219 #ifdef OVERHEAD_DEBUG
1220 do_gettimeofday(&swap_tv2);
1222 swap_sum_time += ((swap_tv2.tv_sec - swap_tv1.tv_sec) * USEC_IN_SEC_NUM +
1223 (swap_tv2.tv_usec - swap_tv1.tv_usec));
1225 #ifdef SUPRESS_BUG_MESSAGES
1226 oops_in_progress = swap_oops_in_progress;
1236 int setjmp_pre_handler (struct kprobe *p, struct pt_regs *regs)
1238 struct jprobe *jp = container_of (p, struct jprobe, kp);
1239 kprobe_pre_entry_handler_t pre_entry;
1240 entry_point_t entry;
1243 // p = kprobe_running(regs);
1246 DBPRINTF ("pjp = 0x%p jp->entry = 0x%p", jp, jp->entry);
1247 entry = (entry_point_t) jp->entry;
1248 pre_entry = (kprobe_pre_entry_handler_t) jp->pre_entry;
1250 // DIE("entry NULL", regs)
1251 DBPRINTF ("entry = 0x%p jp->entry = 0x%p", entry, jp->entry);
1253 //call handler for all kernel probes and user space ones which belong to current tgid
1254 if (!p->tgid || (p->tgid == current->tgid))
1256 if(!p->tgid && ((unsigned int)p->addr == sched_addr) && sched_rp) {
1257 patch_suspended_all_task_ret_addr(sched_rp);
1260 p->ss_addr = (void *)pre_entry (jp->priv_arg, regs);
1262 entry (regs->ARM_r0, regs->ARM_r1, regs->ARM_r2, regs->ARM_r3, regs->ARM_r4, regs->ARM_r5);
1266 dbi_arch_uprobe_return ();
1268 dbi_jprobe_return ();
1272 dbi_arch_uprobe_return ();
1274 prepare_singlestep (p, regs);
1279 void dbi_jprobe_return (void)
1283 void dbi_arch_uprobe_return (void)
1287 int longjmp_break_handler (struct kprobe *p, struct pt_regs *regs)
1290 //kprobe_opcode_t insn = BREAKPOINT_INSTRUCTION;
1291 kprobe_opcode_t insns[2];
1295 insns[0] = BREAKPOINT_INSTRUCTION;
1296 insns[1] = p->opcode;
1297 //p->opcode = *p->addr;
1298 if (read_proc_vm_atomic (current, (unsigned long) (p->addr), &(p->opcode), sizeof (p->opcode)) < sizeof (p->opcode))
1300 printk ("ERROR[%lu]: failed to read vm of proc %s/%u addr %p.", nCount, current->comm, current->pid, p->addr);
1303 //*p->addr = BREAKPOINT_INSTRUCTION;
1304 //*(p->addr+1) = p->opcode;
1305 if (write_proc_vm_atomic (current, (unsigned long) (p->addr), insns, sizeof (insns)) < sizeof (insns))
1307 printk ("ERROR[%lu]: failed to write vm of proc %s/%u addr %p.", nCount, current->comm, current->pid, p->addr);
1313 DBPRINTF ("p->opcode = 0x%lx *p->addr = 0x%lx p->addr = 0x%p\n", p->opcode, *p->addr, p->addr);
1314 *(p->addr + 1) = p->opcode;
1315 p->opcode = *p->addr;
1316 *p->addr = BREAKPOINT_INSTRUCTION;
1318 flush_icache_range ((unsigned int) p->addr, (unsigned int) (((unsigned int) p->addr) + (sizeof (kprobe_opcode_t) * 2)));
1321 reset_current_kprobe();
1329 void arch_arm_kprobe (struct kprobe *p)
1331 *p->addr = BREAKPOINT_INSTRUCTION;
1332 flush_icache_range ((unsigned long) p->addr, (unsigned long) p->addr + sizeof (kprobe_opcode_t));
1335 void arch_disarm_kprobe (struct kprobe *p)
1337 *p->addr = p->opcode;
1338 flush_icache_range ((unsigned long) p->addr, (unsigned long) p->addr + sizeof (kprobe_opcode_t));
1342 int trampoline_probe_handler (struct kprobe *p, struct pt_regs *regs)
1344 struct kretprobe_instance *ri = NULL;
1345 struct hlist_head *head;
1346 struct hlist_node *node, *tmp;
1347 unsigned long flags, orig_ret_address = 0;
1348 unsigned long trampoline_address = (unsigned long) &kretprobe_trampoline;
1350 struct kretprobe *crp = NULL;
1351 struct kprobe_ctlblk *kcb = get_kprobe_ctlblk ();
1356 // in case of user space retprobe trampoline is at the Nth instruction of US tramp
1357 if (!thumb_mode( regs ))
1358 trampoline_address = (unsigned long)(p->ainsn.insn + UPROBES_TRAMP_RET_BREAK_IDX);
1360 trampoline_address = (unsigned long)(p->ainsn.insn) + 0x1b;
1363 spin_lock_irqsave (&kretprobe_lock, flags);
1366 * We are using different hash keys (current and mm) for finding kernel
1367 * space and user space probes. Kernel space probes can change mm field in
1368 * task_struct. User space probes can be shared between threads of one
1369 * process so they have different current but same mm.
1372 head = kretprobe_inst_table_head(current->mm);
1374 head = kretprobe_inst_table_head(current);
1378 * It is possible to have multiple instances associated with a given
1379 * task either because an multiple functions in the call path
1380 * have a return probe installed on them, and/or more then one
1381 * return probe was registered for a target function.
1383 * We can handle this because:
1384 * - instances are always inserted at the head of the list
1385 * - when multiple return probes are registered for the same
1386 * function, the first instance's ret_addr will point to the
1387 * real return address, and all the rest will point to
1388 * kretprobe_trampoline
1390 hlist_for_each_entry_safe (ri, node, tmp, head, hlist)
1392 if (ri->task != current)
1393 /* another task is sharing our hash bucket */
1395 if (ri->rp && ri->rp->handler){
1396 ri->rp->handler (ri, regs, ri->rp->priv_arg);
1399 orig_ret_address = (unsigned long) ri->ret_addr;
1400 recycle_rp_inst (ri);
1401 if (orig_ret_address != trampoline_address)
1403 * This is the real return address. Any other
1404 * instances associated with this task are for
1405 * other calls deeper on the call stack
1409 kretprobe_assert (ri, orig_ret_address, trampoline_address);
1410 //BUG_ON(!orig_ret_address || (orig_ret_address == trampoline_address));
1411 //E.G. Check this code in case of __switch_to function instrumentation -- currently this code generates dump in this case
1412 //if (trampoline_address != (unsigned long) &kretprobe_trampoline){
1413 //if (ri->rp2) BUG_ON (ri->rp2->kp.tgid == 0);
1414 //if (ri->rp) BUG_ON (ri->rp->kp.tgid == 0);
1415 //else if (ri->rp2) BUG_ON (ri->rp2->kp.tgid == 0);
1417 if ((ri->rp && ri->rp->kp.tgid) || (ri->rp2 && ri->rp2->kp.tgid))
1418 BUG_ON (trampoline_address == (unsigned long) &kretprobe_trampoline);
1420 regs->uregs[14] = orig_ret_address;
1421 DBPRINTF ("regs->uregs[14] = 0x%lx\n", regs->uregs[14]);
1422 DBPRINTF ("regs->uregs[15] = 0x%lx\n", regs->uregs[15]);
1424 if (trampoline_address != (unsigned long) &kretprobe_trampoline)
1426 regs->uregs[15] = orig_ret_address;
1428 if (!thumb_mode( regs )) regs->uregs[15] += 4;
1429 else regs->uregs[15] += 2;
1432 DBPRINTF ("regs->uregs[15] = 0x%lx\n", regs->uregs[15]);
1434 if(p){ // ARM, MIPS, X86 user space
1435 if (thumb_mode( regs ) && !(regs->uregs[14] & 0x01))
1437 regs->ARM_cpsr &= 0xFFFFFFDF;
1439 if (user_mode( regs ) && (regs->uregs[14] & 0x01))
1441 regs->ARM_cpsr |= 0x20;
1445 //TODO: test - enter function, delete us retprobe, exit function
1446 // for user space retprobes only - deferred deletion
1448 if (trampoline_address != (unsigned long) &kretprobe_trampoline)
1450 // if we are not at the end of the list and current retprobe should be disarmed
1451 if (node && ri->rp2)
1453 struct hlist_node *current_node = node;
1455 /*sprintf(die_msg, "deferred disarm p->addr = %p [%lx %lx %lx]\n",
1456 crp->kp.addr, *kaddrs[0], *kaddrs[1], *kaddrs[2]);
1457 DIE(die_msg, regs); */
1458 // look for other instances for the same retprobe
1459 hlist_for_each_entry_safe (ri, node, tmp, head, hlist)
1462 * Trying to find another retprobe instance associated with
1463 * the same retprobe.
1465 if (ri->rp2 == crp && node != current_node)
1471 // if there are no more instances for this retprobe
1473 struct kprobe *is_p = &crp->kp;
1474 DBPRINTF ("defered retprobe deletion p->addr = %p", crp->kp.addr);
1476 If there is no any retprobe instances of this retprobe
1477 we can free the resources related to the probe.
1479 if (!(hlist_unhashed(&is_p->is_hlist_arm))) {
1480 hlist_del_rcu(&is_p->is_hlist_arm);
1482 if (!(hlist_unhashed(&is_p->is_hlist_thumb))) {
1483 hlist_del_rcu(&is_p->is_hlist_thumb);
1485 unregister_uprobe (&crp->kp, current, 1);
1488 hlist_del(current_node);
1492 if (kcb->kprobe_status == KPROBE_REENTER) {
1493 restore_previous_kprobe(kcb);
1495 reset_current_kprobe();
1499 spin_unlock_irqrestore (&kretprobe_lock, flags);
1502 * By returning a non-zero value, we are telling
1503 * kprobe_handler() that we don't want the post_handler
1504 * to run (and have re-enabled preemption)
1510 void __arch_prepare_kretprobe (struct kretprobe *rp, struct pt_regs *regs)
1512 struct kretprobe_instance *ri;
1514 DBPRINTF ("start\n");
1515 //TODO: test - remove retprobe after func entry but before its exit
1516 if ((ri = get_free_rp_inst (rp)) != NULL)
1521 ri->ret_addr = (kprobe_opcode_t *) regs->uregs[14];
1524 if (!thumb_mode( regs ))
1525 regs->uregs[14] = (unsigned long) (rp->kp.ainsn.insn + UPROBES_TRAMP_RET_BREAK_IDX);
1527 regs->uregs[14] = (unsigned long) (rp->kp.ainsn.insn) + 0x1b;
1529 else /* Replace the return addr with trampoline addr */
1530 regs->uregs[14] = (unsigned long) &kretprobe_trampoline;
1532 // DBPRINTF ("ret addr set to %p->%lx\n", ri->ret_addr, regs->uregs[14]);
1536 DBPRINTF ("WARNING: missed retprobe %p\n", rp->kp.addr);
1542 int asm_init_module_dependencies()
1544 //No module dependencies
1549 void (* do_kpro)(struct undef_hook *);
1550 void (* undo_kpro)(struct undef_hook *);
1552 // kernel probes hook
1553 struct undef_hook undef_ho_k = {
1554 .instr_mask = 0xffffffff,
1555 .instr_val = BREAKPOINT_INSTRUCTION,
1556 .cpsr_mask = MODE_MASK,
1557 .cpsr_val = SVC_MODE,
1558 .fn = kprobe_trap_handler
1561 // userspace probes hook (arm)
1562 struct undef_hook undef_ho_u = {
1563 .instr_mask = 0xffffffff,
1564 .instr_val = BREAKPOINT_INSTRUCTION,
1565 .cpsr_mask = MODE_MASK,
1566 .cpsr_val = USR_MODE,
1567 .fn = kprobe_trap_handler
1570 // userspace probes hook (thumb)
1571 struct undef_hook undef_ho_u_t = {
1572 .instr_mask = 0xffffffff,
1573 .instr_val = BREAKPOINT_INSTRUCTION & 0x0000ffff,
1574 .cpsr_mask = MODE_MASK,
1575 .cpsr_val = USR_MODE,
1576 .fn = kprobe_trap_handler
1579 int __init arch_init_kprobes (void)
1581 unsigned int do_bp_handler = 0;
1584 if (arch_init_module_dependencies())
1586 DBPRINTF ("Unable to init module dependencies\n");
1590 do_bp_handler = (unsigned int) kallsyms_search ("do_undefinstr");
1591 if (do_bp_handler == 0) {
1592 DBPRINTF("no do_undefinstr symbol found!");
1595 arr_traps_template[NOTIFIER_CALL_CHAIN_INDEX] = arch_construct_brunch ((unsigned int)kprobe_handler, do_bp_handler + NOTIFIER_CALL_CHAIN_INDEX * 4, 1);
1596 // Register hooks (kprobe_handler)
1597 do_kpro = (void *)kallsyms_search ("register_undef_hook");
1599 printk("no register_undef_hook symbol found!\n");
1603 // Unregister hooks (kprobe_handler)
1604 undo_kpro = (void *)kallsyms_search ("unregister_undef_hook");
1605 if (undo_kpro == 0) {
1606 printk("no unregister_undef_hook symbol found!\n");
1610 do_kpro(&undef_ho_k);
1611 do_kpro(&undef_ho_u);
1612 do_kpro(&undef_ho_u_t);
1613 if ((ret = dbi_register_kprobe (&trampoline_p)) != 0) {
1614 //dbi_unregister_jprobe(&do_exit_p, 0);
1620 void __exit dbi_arch_exit_kprobes (void)
1622 undo_kpro(&undef_ho_u_t);
1623 undo_kpro(&undef_ho_u);
1624 undo_kpro(&undef_ho_k);
1627 //EXPORT_SYMBOL_GPL (dbi_arch_uprobe_return);
1628 //EXPORT_SYMBOL_GPL (dbi_arch_exit_kprobes);