kprobes-arm.c 55 KB

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  1. /*
  2. * arch/arm/kernel/kprobes-decode.c
  3. *
  4. * Copyright (C) 2006, 2007 Motorola Inc.
  5. *
  6. * This program is free software; you can redistribute it and/or modify
  7. * it under the terms of the GNU General Public License version 2 as
  8. * published by the Free Software Foundation.
  9. *
  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 GNU
  13. * General Public License for more details.
  14. */
  15. /*
  16. * We do not have hardware single-stepping on ARM, This
  17. * effort is further complicated by the ARM not having a
  18. * "next PC" register. Instructions that change the PC
  19. * can't be safely single-stepped in a MP environment, so
  20. * we have a lot of work to do:
  21. *
  22. * In the prepare phase:
  23. * *) If it is an instruction that does anything
  24. * with the CPU mode, we reject it for a kprobe.
  25. * (This is out of laziness rather than need. The
  26. * instructions could be simulated.)
  27. *
  28. * *) Otherwise, decode the instruction rewriting its
  29. * registers to take fixed, ordered registers and
  30. * setting a handler for it to run the instruction.
  31. *
  32. * In the execution phase by an instruction's handler:
  33. *
  34. * *) If the PC is written to by the instruction, the
  35. * instruction must be fully simulated in software.
  36. *
  37. * *) Otherwise, a modified form of the instruction is
  38. * directly executed. Its handler calls the
  39. * instruction in insn[0]. In insn[1] is a
  40. * "mov pc, lr" to return.
  41. *
  42. * Before calling, load up the reordered registers
  43. * from the original instruction's registers. If one
  44. * of the original input registers is the PC, compute
  45. * and adjust the appropriate input register.
  46. *
  47. * After call completes, copy the output registers to
  48. * the original instruction's original registers.
  49. *
  50. * We don't use a real breakpoint instruction since that
  51. * would have us in the kernel go from SVC mode to SVC
  52. * mode losing the link register. Instead we use an
  53. * undefined instruction. To simplify processing, the
  54. * undefined instruction used for kprobes must be reserved
  55. * exclusively for kprobes use.
  56. *
  57. * TODO: ifdef out some instruction decoding based on architecture.
  58. */
  59. #include <linux/kernel.h>
  60. #include <linux/kprobes.h>
  61. #include "kprobes.h"
  62. #define sign_extend(x, signbit) ((x) | (0 - ((x) & (1 << (signbit)))))
  63. #define branch_displacement(insn) sign_extend(((insn) & 0xffffff) << 2, 25)
  64. #if __LINUX_ARM_ARCH__ >= 6
  65. #define BLX(reg) "blx "reg" \n\t"
  66. #else
  67. #define BLX(reg) "mov lr, pc \n\t" \
  68. "mov pc, "reg" \n\t"
  69. #endif
  70. #define is_r15(insn, bitpos) (((insn) & (0xf << bitpos)) == (0xf << bitpos))
  71. #define PSR_fs (PSR_f|PSR_s)
  72. #define KPROBE_RETURN_INSTRUCTION 0xe1a0f00e /* mov pc, lr */
  73. typedef long (insn_0arg_fn_t)(void);
  74. typedef long (insn_1arg_fn_t)(long);
  75. typedef long (insn_2arg_fn_t)(long, long);
  76. typedef long (insn_3arg_fn_t)(long, long, long);
  77. typedef long (insn_4arg_fn_t)(long, long, long, long);
  78. typedef long long (insn_llret_0arg_fn_t)(void);
  79. typedef long long (insn_llret_3arg_fn_t)(long, long, long);
  80. typedef long long (insn_llret_4arg_fn_t)(long, long, long, long);
  81. union reg_pair {
  82. long long dr;
  83. #ifdef __LITTLE_ENDIAN
  84. struct { long r0, r1; };
  85. #else
  86. struct { long r1, r0; };
  87. #endif
  88. };
  89. /*
  90. * The insnslot_?arg_r[w]flags() functions below are to keep the
  91. * msr -> *fn -> mrs instruction sequences indivisible so that
  92. * the state of the CPSR flags aren't inadvertently modified
  93. * just before or just after the call.
  94. */
  95. static inline long __kprobes
  96. insnslot_0arg_rflags(long cpsr, insn_0arg_fn_t *fn)
  97. {
  98. register long ret asm("r0");
  99. __asm__ __volatile__ (
  100. "msr cpsr_fs, %[cpsr] \n\t"
  101. "mov lr, pc \n\t"
  102. "mov pc, %[fn] \n\t"
  103. : "=r" (ret)
  104. : [cpsr] "r" (cpsr), [fn] "r" (fn)
  105. : "lr", "cc"
  106. );
  107. return ret;
  108. }
  109. static inline long long __kprobes
  110. insnslot_llret_0arg_rflags(long cpsr, insn_llret_0arg_fn_t *fn)
  111. {
  112. register long ret0 asm("r0");
  113. register long ret1 asm("r1");
  114. union reg_pair fnr;
  115. __asm__ __volatile__ (
  116. "msr cpsr_fs, %[cpsr] \n\t"
  117. "mov lr, pc \n\t"
  118. "mov pc, %[fn] \n\t"
  119. : "=r" (ret0), "=r" (ret1)
  120. : [cpsr] "r" (cpsr), [fn] "r" (fn)
  121. : "lr", "cc"
  122. );
  123. fnr.r0 = ret0;
  124. fnr.r1 = ret1;
  125. return fnr.dr;
  126. }
  127. static inline long __kprobes
  128. insnslot_1arg_rflags(long r0, long cpsr, insn_1arg_fn_t *fn)
  129. {
  130. register long rr0 asm("r0") = r0;
  131. register long ret asm("r0");
  132. __asm__ __volatile__ (
  133. "msr cpsr_fs, %[cpsr] \n\t"
  134. "mov lr, pc \n\t"
  135. "mov pc, %[fn] \n\t"
  136. : "=r" (ret)
  137. : "0" (rr0), [cpsr] "r" (cpsr), [fn] "r" (fn)
  138. : "lr", "cc"
  139. );
  140. return ret;
  141. }
  142. static inline long __kprobes
  143. insnslot_2arg_rflags(long r0, long r1, long cpsr, insn_2arg_fn_t *fn)
  144. {
  145. register long rr0 asm("r0") = r0;
  146. register long rr1 asm("r1") = r1;
  147. register long ret asm("r0");
  148. __asm__ __volatile__ (
  149. "msr cpsr_fs, %[cpsr] \n\t"
  150. "mov lr, pc \n\t"
  151. "mov pc, %[fn] \n\t"
  152. : "=r" (ret)
  153. : "0" (rr0), "r" (rr1),
  154. [cpsr] "r" (cpsr), [fn] "r" (fn)
  155. : "lr", "cc"
  156. );
  157. return ret;
  158. }
  159. static inline long __kprobes
  160. insnslot_3arg_rflags(long r0, long r1, long r2, long cpsr, insn_3arg_fn_t *fn)
  161. {
  162. register long rr0 asm("r0") = r0;
  163. register long rr1 asm("r1") = r1;
  164. register long rr2 asm("r2") = r2;
  165. register long ret asm("r0");
  166. __asm__ __volatile__ (
  167. "msr cpsr_fs, %[cpsr] \n\t"
  168. "mov lr, pc \n\t"
  169. "mov pc, %[fn] \n\t"
  170. : "=r" (ret)
  171. : "0" (rr0), "r" (rr1), "r" (rr2),
  172. [cpsr] "r" (cpsr), [fn] "r" (fn)
  173. : "lr", "cc"
  174. );
  175. return ret;
  176. }
  177. static inline long long __kprobes
  178. insnslot_llret_3arg_rflags(long r0, long r1, long r2, long cpsr,
  179. insn_llret_3arg_fn_t *fn)
  180. {
  181. register long rr0 asm("r0") = r0;
  182. register long rr1 asm("r1") = r1;
  183. register long rr2 asm("r2") = r2;
  184. register long ret0 asm("r0");
  185. register long ret1 asm("r1");
  186. union reg_pair fnr;
  187. __asm__ __volatile__ (
  188. "msr cpsr_fs, %[cpsr] \n\t"
  189. "mov lr, pc \n\t"
  190. "mov pc, %[fn] \n\t"
  191. : "=r" (ret0), "=r" (ret1)
  192. : "0" (rr0), "r" (rr1), "r" (rr2),
  193. [cpsr] "r" (cpsr), [fn] "r" (fn)
  194. : "lr", "cc"
  195. );
  196. fnr.r0 = ret0;
  197. fnr.r1 = ret1;
  198. return fnr.dr;
  199. }
  200. static inline long __kprobes
  201. insnslot_4arg_rflags(long r0, long r1, long r2, long r3, long cpsr,
  202. insn_4arg_fn_t *fn)
  203. {
  204. register long rr0 asm("r0") = r0;
  205. register long rr1 asm("r1") = r1;
  206. register long rr2 asm("r2") = r2;
  207. register long rr3 asm("r3") = r3;
  208. register long ret asm("r0");
  209. __asm__ __volatile__ (
  210. "msr cpsr_fs, %[cpsr] \n\t"
  211. "mov lr, pc \n\t"
  212. "mov pc, %[fn] \n\t"
  213. : "=r" (ret)
  214. : "0" (rr0), "r" (rr1), "r" (rr2), "r" (rr3),
  215. [cpsr] "r" (cpsr), [fn] "r" (fn)
  216. : "lr", "cc"
  217. );
  218. return ret;
  219. }
  220. static inline long __kprobes
  221. insnslot_1arg_rwflags(long r0, long *cpsr, insn_1arg_fn_t *fn)
  222. {
  223. register long rr0 asm("r0") = r0;
  224. register long ret asm("r0");
  225. long oldcpsr = *cpsr;
  226. long newcpsr;
  227. __asm__ __volatile__ (
  228. "msr cpsr_fs, %[oldcpsr] \n\t"
  229. "mov lr, pc \n\t"
  230. "mov pc, %[fn] \n\t"
  231. "mrs %[newcpsr], cpsr \n\t"
  232. : "=r" (ret), [newcpsr] "=r" (newcpsr)
  233. : "0" (rr0), [oldcpsr] "r" (oldcpsr), [fn] "r" (fn)
  234. : "lr", "cc"
  235. );
  236. *cpsr = (oldcpsr & ~PSR_fs) | (newcpsr & PSR_fs);
  237. return ret;
  238. }
  239. static inline long __kprobes
  240. insnslot_2arg_rwflags(long r0, long r1, long *cpsr, insn_2arg_fn_t *fn)
  241. {
  242. register long rr0 asm("r0") = r0;
  243. register long rr1 asm("r1") = r1;
  244. register long ret asm("r0");
  245. long oldcpsr = *cpsr;
  246. long newcpsr;
  247. __asm__ __volatile__ (
  248. "msr cpsr_fs, %[oldcpsr] \n\t"
  249. "mov lr, pc \n\t"
  250. "mov pc, %[fn] \n\t"
  251. "mrs %[newcpsr], cpsr \n\t"
  252. : "=r" (ret), [newcpsr] "=r" (newcpsr)
  253. : "0" (rr0), "r" (rr1), [oldcpsr] "r" (oldcpsr), [fn] "r" (fn)
  254. : "lr", "cc"
  255. );
  256. *cpsr = (oldcpsr & ~PSR_fs) | (newcpsr & PSR_fs);
  257. return ret;
  258. }
  259. static inline long __kprobes
  260. insnslot_3arg_rwflags(long r0, long r1, long r2, long *cpsr,
  261. insn_3arg_fn_t *fn)
  262. {
  263. register long rr0 asm("r0") = r0;
  264. register long rr1 asm("r1") = r1;
  265. register long rr2 asm("r2") = r2;
  266. register long ret asm("r0");
  267. long oldcpsr = *cpsr;
  268. long newcpsr;
  269. __asm__ __volatile__ (
  270. "msr cpsr_fs, %[oldcpsr] \n\t"
  271. "mov lr, pc \n\t"
  272. "mov pc, %[fn] \n\t"
  273. "mrs %[newcpsr], cpsr \n\t"
  274. : "=r" (ret), [newcpsr] "=r" (newcpsr)
  275. : "0" (rr0), "r" (rr1), "r" (rr2),
  276. [oldcpsr] "r" (oldcpsr), [fn] "r" (fn)
  277. : "lr", "cc"
  278. );
  279. *cpsr = (oldcpsr & ~PSR_fs) | (newcpsr & PSR_fs);
  280. return ret;
  281. }
  282. static inline long __kprobes
  283. insnslot_4arg_rwflags(long r0, long r1, long r2, long r3, long *cpsr,
  284. insn_4arg_fn_t *fn)
  285. {
  286. register long rr0 asm("r0") = r0;
  287. register long rr1 asm("r1") = r1;
  288. register long rr2 asm("r2") = r2;
  289. register long rr3 asm("r3") = r3;
  290. register long ret asm("r0");
  291. long oldcpsr = *cpsr;
  292. long newcpsr;
  293. __asm__ __volatile__ (
  294. "msr cpsr_fs, %[oldcpsr] \n\t"
  295. "mov lr, pc \n\t"
  296. "mov pc, %[fn] \n\t"
  297. "mrs %[newcpsr], cpsr \n\t"
  298. : "=r" (ret), [newcpsr] "=r" (newcpsr)
  299. : "0" (rr0), "r" (rr1), "r" (rr2), "r" (rr3),
  300. [oldcpsr] "r" (oldcpsr), [fn] "r" (fn)
  301. : "lr", "cc"
  302. );
  303. *cpsr = (oldcpsr & ~PSR_fs) | (newcpsr & PSR_fs);
  304. return ret;
  305. }
  306. static inline long long __kprobes
  307. insnslot_llret_4arg_rwflags(long r0, long r1, long r2, long r3, long *cpsr,
  308. insn_llret_4arg_fn_t *fn)
  309. {
  310. register long rr0 asm("r0") = r0;
  311. register long rr1 asm("r1") = r1;
  312. register long rr2 asm("r2") = r2;
  313. register long rr3 asm("r3") = r3;
  314. register long ret0 asm("r0");
  315. register long ret1 asm("r1");
  316. long oldcpsr = *cpsr;
  317. long newcpsr;
  318. union reg_pair fnr;
  319. __asm__ __volatile__ (
  320. "msr cpsr_fs, %[oldcpsr] \n\t"
  321. "mov lr, pc \n\t"
  322. "mov pc, %[fn] \n\t"
  323. "mrs %[newcpsr], cpsr \n\t"
  324. : "=r" (ret0), "=r" (ret1), [newcpsr] "=r" (newcpsr)
  325. : "0" (rr0), "r" (rr1), "r" (rr2), "r" (rr3),
  326. [oldcpsr] "r" (oldcpsr), [fn] "r" (fn)
  327. : "lr", "cc"
  328. );
  329. *cpsr = (oldcpsr & ~PSR_fs) | (newcpsr & PSR_fs);
  330. fnr.r0 = ret0;
  331. fnr.r1 = ret1;
  332. return fnr.dr;
  333. }
  334. /*
  335. * To avoid the complications of mimicing single-stepping on a
  336. * processor without a Next-PC or a single-step mode, and to
  337. * avoid having to deal with the side-effects of boosting, we
  338. * simulate or emulate (almost) all ARM instructions.
  339. *
  340. * "Simulation" is where the instruction's behavior is duplicated in
  341. * C code. "Emulation" is where the original instruction is rewritten
  342. * and executed, often by altering its registers.
  343. *
  344. * By having all behavior of the kprobe'd instruction completed before
  345. * returning from the kprobe_handler(), all locks (scheduler and
  346. * interrupt) can safely be released. There is no need for secondary
  347. * breakpoints, no race with MP or preemptable kernels, nor having to
  348. * clean up resources counts at a later time impacting overall system
  349. * performance. By rewriting the instruction, only the minimum registers
  350. * need to be loaded and saved back optimizing performance.
  351. *
  352. * Calling the insnslot_*_rwflags version of a function doesn't hurt
  353. * anything even when the CPSR flags aren't updated by the
  354. * instruction. It's just a little slower in return for saving
  355. * a little space by not having a duplicate function that doesn't
  356. * update the flags. (The same optimization can be said for
  357. * instructions that do or don't perform register writeback)
  358. * Also, instructions can either read the flags, only write the
  359. * flags, or read and write the flags. To save combinations
  360. * rather than for sheer performance, flag functions just assume
  361. * read and write of flags.
  362. */
  363. static void __kprobes simulate_bbl(struct kprobe *p, struct pt_regs *regs)
  364. {
  365. kprobe_opcode_t insn = p->opcode;
  366. long iaddr = (long)p->addr;
  367. int disp = branch_displacement(insn);
  368. if (insn & (1 << 24))
  369. regs->ARM_lr = iaddr + 4;
  370. regs->ARM_pc = iaddr + 8 + disp;
  371. }
  372. static void __kprobes simulate_blx1(struct kprobe *p, struct pt_regs *regs)
  373. {
  374. kprobe_opcode_t insn = p->opcode;
  375. long iaddr = (long)p->addr;
  376. int disp = branch_displacement(insn);
  377. regs->ARM_lr = iaddr + 4;
  378. regs->ARM_pc = iaddr + 8 + disp + ((insn >> 23) & 0x2);
  379. regs->ARM_cpsr |= PSR_T_BIT;
  380. }
  381. static void __kprobes simulate_blx2bx(struct kprobe *p, struct pt_regs *regs)
  382. {
  383. kprobe_opcode_t insn = p->opcode;
  384. int rm = insn & 0xf;
  385. long rmv = regs->uregs[rm];
  386. if (insn & (1 << 5))
  387. regs->ARM_lr = (long)p->addr + 4;
  388. regs->ARM_pc = rmv & ~0x1;
  389. regs->ARM_cpsr &= ~PSR_T_BIT;
  390. if (rmv & 0x1)
  391. regs->ARM_cpsr |= PSR_T_BIT;
  392. }
  393. static void __kprobes simulate_mrs(struct kprobe *p, struct pt_regs *regs)
  394. {
  395. kprobe_opcode_t insn = p->opcode;
  396. int rd = (insn >> 12) & 0xf;
  397. unsigned long mask = 0xf8ff03df; /* Mask out execution state */
  398. regs->uregs[rd] = regs->ARM_cpsr & mask;
  399. }
  400. static void __kprobes simulate_mov_ipsp(struct kprobe *p, struct pt_regs *regs)
  401. {
  402. regs->uregs[12] = regs->uregs[13];
  403. }
  404. static void __kprobes emulate_ldrd(struct kprobe *p, struct pt_regs *regs)
  405. {
  406. insn_2arg_fn_t *i_fn = (insn_2arg_fn_t *)&p->ainsn.insn[0];
  407. kprobe_opcode_t insn = p->opcode;
  408. long ppc = (long)p->addr + 8;
  409. int rd = (insn >> 12) & 0xf;
  410. int rn = (insn >> 16) & 0xf;
  411. int rm = insn & 0xf; /* rm may be invalid, don't care. */
  412. long rmv = (rm == 15) ? ppc : regs->uregs[rm];
  413. long rnv = (rn == 15) ? ppc : regs->uregs[rn];
  414. /* Not following the C calling convention here, so need asm(). */
  415. __asm__ __volatile__ (
  416. "ldr r0, %[rn] \n\t"
  417. "ldr r1, %[rm] \n\t"
  418. "msr cpsr_fs, %[cpsr]\n\t"
  419. "mov lr, pc \n\t"
  420. "mov pc, %[i_fn] \n\t"
  421. "str r0, %[rn] \n\t" /* in case of writeback */
  422. "str r2, %[rd0] \n\t"
  423. "str r3, %[rd1] \n\t"
  424. : [rn] "+m" (rnv),
  425. [rd0] "=m" (regs->uregs[rd]),
  426. [rd1] "=m" (regs->uregs[rd+1])
  427. : [rm] "m" (rmv),
  428. [cpsr] "r" (regs->ARM_cpsr),
  429. [i_fn] "r" (i_fn)
  430. : "r0", "r1", "r2", "r3", "lr", "cc"
  431. );
  432. if (is_writeback(insn))
  433. regs->uregs[rn] = rnv;
  434. }
  435. static void __kprobes emulate_strd(struct kprobe *p, struct pt_regs *regs)
  436. {
  437. insn_4arg_fn_t *i_fn = (insn_4arg_fn_t *)&p->ainsn.insn[0];
  438. kprobe_opcode_t insn = p->opcode;
  439. long ppc = (long)p->addr + 8;
  440. int rd = (insn >> 12) & 0xf;
  441. int rn = (insn >> 16) & 0xf;
  442. int rm = insn & 0xf;
  443. long rnv = (rn == 15) ? ppc : regs->uregs[rn];
  444. /* rm/rmv may be invalid, don't care. */
  445. long rmv = (rm == 15) ? ppc : regs->uregs[rm];
  446. long rnv_wb;
  447. rnv_wb = insnslot_4arg_rflags(rnv, rmv, regs->uregs[rd],
  448. regs->uregs[rd+1],
  449. regs->ARM_cpsr, i_fn);
  450. if (is_writeback(insn))
  451. regs->uregs[rn] = rnv_wb;
  452. }
  453. static void __kprobes emulate_ldr_old(struct kprobe *p, struct pt_regs *regs)
  454. {
  455. insn_llret_3arg_fn_t *i_fn = (insn_llret_3arg_fn_t *)&p->ainsn.insn[0];
  456. kprobe_opcode_t insn = p->opcode;
  457. long ppc = (long)p->addr + 8;
  458. union reg_pair fnr;
  459. int rd = (insn >> 12) & 0xf;
  460. int rn = (insn >> 16) & 0xf;
  461. int rm = insn & 0xf;
  462. long rdv;
  463. long rnv = (rn == 15) ? ppc : regs->uregs[rn];
  464. long rmv = (rm == 15) ? ppc : regs->uregs[rm];
  465. long cpsr = regs->ARM_cpsr;
  466. fnr.dr = insnslot_llret_3arg_rflags(rnv, 0, rmv, cpsr, i_fn);
  467. if (rn != 15)
  468. regs->uregs[rn] = fnr.r0; /* Save Rn in case of writeback. */
  469. rdv = fnr.r1;
  470. if (rd == 15) {
  471. #if __LINUX_ARM_ARCH__ >= 5
  472. cpsr &= ~PSR_T_BIT;
  473. if (rdv & 0x1)
  474. cpsr |= PSR_T_BIT;
  475. regs->ARM_cpsr = cpsr;
  476. rdv &= ~0x1;
  477. #else
  478. rdv &= ~0x2;
  479. #endif
  480. }
  481. regs->uregs[rd] = rdv;
  482. }
  483. static void __kprobes emulate_str_old(struct kprobe *p, struct pt_regs *regs)
  484. {
  485. insn_3arg_fn_t *i_fn = (insn_3arg_fn_t *)&p->ainsn.insn[0];
  486. kprobe_opcode_t insn = p->opcode;
  487. long iaddr = (long)p->addr;
  488. int rd = (insn >> 12) & 0xf;
  489. int rn = (insn >> 16) & 0xf;
  490. int rm = insn & 0xf;
  491. long rdv = (rd == 15) ? iaddr + str_pc_offset : regs->uregs[rd];
  492. long rnv = (rn == 15) ? iaddr + 8 : regs->uregs[rn];
  493. long rmv = regs->uregs[rm]; /* rm/rmv may be invalid, don't care. */
  494. long rnv_wb;
  495. rnv_wb = insnslot_3arg_rflags(rnv, rdv, rmv, regs->ARM_cpsr, i_fn);
  496. if (rn != 15)
  497. regs->uregs[rn] = rnv_wb; /* Save Rn in case of writeback. */
  498. }
  499. static void __kprobes emulate_sat(struct kprobe *p, struct pt_regs *regs)
  500. {
  501. insn_1arg_fn_t *i_fn = (insn_1arg_fn_t *)&p->ainsn.insn[0];
  502. kprobe_opcode_t insn = p->opcode;
  503. int rd = (insn >> 12) & 0xf;
  504. int rm = insn & 0xf;
  505. long rmv = regs->uregs[rm];
  506. /* Writes Q flag */
  507. regs->uregs[rd] = insnslot_1arg_rwflags(rmv, &regs->ARM_cpsr, i_fn);
  508. }
  509. static void __kprobes emulate_sel(struct kprobe *p, struct pt_regs *regs)
  510. {
  511. insn_2arg_fn_t *i_fn = (insn_2arg_fn_t *)&p->ainsn.insn[0];
  512. kprobe_opcode_t insn = p->opcode;
  513. int rd = (insn >> 12) & 0xf;
  514. int rn = (insn >> 16) & 0xf;
  515. int rm = insn & 0xf;
  516. long rnv = regs->uregs[rn];
  517. long rmv = regs->uregs[rm];
  518. /* Reads GE bits */
  519. regs->uregs[rd] = insnslot_2arg_rflags(rnv, rmv, regs->ARM_cpsr, i_fn);
  520. }
  521. static void __kprobes emulate_none(struct kprobe *p, struct pt_regs *regs)
  522. {
  523. insn_0arg_fn_t *i_fn = (insn_0arg_fn_t *)&p->ainsn.insn[0];
  524. insnslot_0arg_rflags(regs->ARM_cpsr, i_fn);
  525. }
  526. static void __kprobes emulate_nop(struct kprobe *p, struct pt_regs *regs)
  527. {
  528. }
  529. static void __kprobes
  530. emulate_rd12_modify(struct kprobe *p, struct pt_regs *regs)
  531. {
  532. insn_1arg_fn_t *i_fn = (insn_1arg_fn_t *)&p->ainsn.insn[0];
  533. kprobe_opcode_t insn = p->opcode;
  534. int rd = (insn >> 12) & 0xf;
  535. long rdv = regs->uregs[rd];
  536. regs->uregs[rd] = insnslot_1arg_rflags(rdv, regs->ARM_cpsr, i_fn);
  537. }
  538. static void __kprobes
  539. emulate_rd12rn0_modify(struct kprobe *p, struct pt_regs *regs)
  540. {
  541. insn_2arg_fn_t *i_fn = (insn_2arg_fn_t *)&p->ainsn.insn[0];
  542. kprobe_opcode_t insn = p->opcode;
  543. int rd = (insn >> 12) & 0xf;
  544. int rn = insn & 0xf;
  545. long rdv = regs->uregs[rd];
  546. long rnv = regs->uregs[rn];
  547. regs->uregs[rd] = insnslot_2arg_rflags(rdv, rnv, regs->ARM_cpsr, i_fn);
  548. }
  549. static void __kprobes emulate_rd12rm0(struct kprobe *p, struct pt_regs *regs)
  550. {
  551. insn_1arg_fn_t *i_fn = (insn_1arg_fn_t *)&p->ainsn.insn[0];
  552. kprobe_opcode_t insn = p->opcode;
  553. int rd = (insn >> 12) & 0xf;
  554. int rm = insn & 0xf;
  555. long rmv = regs->uregs[rm];
  556. regs->uregs[rd] = insnslot_1arg_rflags(rmv, regs->ARM_cpsr, i_fn);
  557. }
  558. static void __kprobes
  559. emulate_rd12rn16rm0_rwflags(struct kprobe *p, struct pt_regs *regs)
  560. {
  561. insn_2arg_fn_t *i_fn = (insn_2arg_fn_t *)&p->ainsn.insn[0];
  562. kprobe_opcode_t insn = p->opcode;
  563. int rd = (insn >> 12) & 0xf;
  564. int rn = (insn >> 16) & 0xf;
  565. int rm = insn & 0xf;
  566. long rnv = regs->uregs[rn];
  567. long rmv = regs->uregs[rm];
  568. regs->uregs[rd] =
  569. insnslot_2arg_rwflags(rnv, rmv, &regs->ARM_cpsr, i_fn);
  570. }
  571. static void __kprobes
  572. emulate_rd16rn12rs8rm0_rwflags(struct kprobe *p, struct pt_regs *regs)
  573. {
  574. insn_3arg_fn_t *i_fn = (insn_3arg_fn_t *)&p->ainsn.insn[0];
  575. kprobe_opcode_t insn = p->opcode;
  576. int rd = (insn >> 16) & 0xf;
  577. int rn = (insn >> 12) & 0xf;
  578. int rs = (insn >> 8) & 0xf;
  579. int rm = insn & 0xf;
  580. long rnv = regs->uregs[rn];
  581. long rsv = regs->uregs[rs];
  582. long rmv = regs->uregs[rm];
  583. regs->uregs[rd] =
  584. insnslot_3arg_rwflags(rnv, rsv, rmv, &regs->ARM_cpsr, i_fn);
  585. }
  586. static void __kprobes
  587. emulate_rd16rs8rm0_rwflags(struct kprobe *p, struct pt_regs *regs)
  588. {
  589. insn_2arg_fn_t *i_fn = (insn_2arg_fn_t *)&p->ainsn.insn[0];
  590. kprobe_opcode_t insn = p->opcode;
  591. int rd = (insn >> 16) & 0xf;
  592. int rs = (insn >> 8) & 0xf;
  593. int rm = insn & 0xf;
  594. long rsv = regs->uregs[rs];
  595. long rmv = regs->uregs[rm];
  596. regs->uregs[rd] =
  597. insnslot_2arg_rwflags(rsv, rmv, &regs->ARM_cpsr, i_fn);
  598. }
  599. static void __kprobes
  600. emulate_rdhi16rdlo12rs8rm0_rwflags(struct kprobe *p, struct pt_regs *regs)
  601. {
  602. insn_llret_4arg_fn_t *i_fn = (insn_llret_4arg_fn_t *)&p->ainsn.insn[0];
  603. kprobe_opcode_t insn = p->opcode;
  604. union reg_pair fnr;
  605. int rdhi = (insn >> 16) & 0xf;
  606. int rdlo = (insn >> 12) & 0xf;
  607. int rs = (insn >> 8) & 0xf;
  608. int rm = insn & 0xf;
  609. long rsv = regs->uregs[rs];
  610. long rmv = regs->uregs[rm];
  611. fnr.dr = insnslot_llret_4arg_rwflags(regs->uregs[rdhi],
  612. regs->uregs[rdlo], rsv, rmv,
  613. &regs->ARM_cpsr, i_fn);
  614. regs->uregs[rdhi] = fnr.r0;
  615. regs->uregs[rdlo] = fnr.r1;
  616. }
  617. static void __kprobes
  618. emulate_alu_imm_rflags(struct kprobe *p, struct pt_regs *regs)
  619. {
  620. insn_1arg_fn_t *i_fn = (insn_1arg_fn_t *)&p->ainsn.insn[0];
  621. kprobe_opcode_t insn = p->opcode;
  622. int rd = (insn >> 12) & 0xf;
  623. int rn = (insn >> 16) & 0xf;
  624. long rnv = (rn == 15) ? (long)p->addr + 8 : regs->uregs[rn];
  625. regs->uregs[rd] = insnslot_1arg_rflags(rnv, regs->ARM_cpsr, i_fn);
  626. }
  627. static void __kprobes
  628. emulate_alu_imm_rwflags(struct kprobe *p, struct pt_regs *regs)
  629. {
  630. insn_1arg_fn_t *i_fn = (insn_1arg_fn_t *)&p->ainsn.insn[0];
  631. kprobe_opcode_t insn = p->opcode;
  632. int rd = (insn >> 12) & 0xf;
  633. int rn = (insn >> 16) & 0xf;
  634. long rnv = (rn == 15) ? (long)p->addr + 8 : regs->uregs[rn];
  635. regs->uregs[rd] = insnslot_1arg_rwflags(rnv, &regs->ARM_cpsr, i_fn);
  636. }
  637. static void __kprobes
  638. emulate_alu_tests_imm(struct kprobe *p, struct pt_regs *regs)
  639. {
  640. insn_1arg_fn_t *i_fn = (insn_1arg_fn_t *)&p->ainsn.insn[0];
  641. kprobe_opcode_t insn = p->opcode;
  642. int rn = (insn >> 16) & 0xf;
  643. long rnv = (rn == 15) ? (long)p->addr + 8 : regs->uregs[rn];
  644. insnslot_1arg_rwflags(rnv, &regs->ARM_cpsr, i_fn);
  645. }
  646. static void __kprobes
  647. emulate_alu_rflags(struct kprobe *p, struct pt_regs *regs)
  648. {
  649. insn_3arg_fn_t *i_fn = (insn_3arg_fn_t *)&p->ainsn.insn[0];
  650. kprobe_opcode_t insn = p->opcode;
  651. long ppc = (long)p->addr + 8;
  652. int rd = (insn >> 12) & 0xf;
  653. int rn = (insn >> 16) & 0xf; /* rn/rnv/rs/rsv may be */
  654. int rs = (insn >> 8) & 0xf; /* invalid, don't care. */
  655. int rm = insn & 0xf;
  656. long rnv = (rn == 15) ? ppc : regs->uregs[rn];
  657. long rmv = (rm == 15) ? ppc : regs->uregs[rm];
  658. long rsv = regs->uregs[rs];
  659. regs->uregs[rd] =
  660. insnslot_3arg_rflags(rnv, rmv, rsv, regs->ARM_cpsr, i_fn);
  661. }
  662. static void __kprobes
  663. emulate_alu_rwflags(struct kprobe *p, struct pt_regs *regs)
  664. {
  665. insn_3arg_fn_t *i_fn = (insn_3arg_fn_t *)&p->ainsn.insn[0];
  666. kprobe_opcode_t insn = p->opcode;
  667. long ppc = (long)p->addr + 8;
  668. int rd = (insn >> 12) & 0xf;
  669. int rn = (insn >> 16) & 0xf; /* rn/rnv/rs/rsv may be */
  670. int rs = (insn >> 8) & 0xf; /* invalid, don't care. */
  671. int rm = insn & 0xf;
  672. long rnv = (rn == 15) ? ppc : regs->uregs[rn];
  673. long rmv = (rm == 15) ? ppc : regs->uregs[rm];
  674. long rsv = regs->uregs[rs];
  675. regs->uregs[rd] =
  676. insnslot_3arg_rwflags(rnv, rmv, rsv, &regs->ARM_cpsr, i_fn);
  677. }
  678. static void __kprobes
  679. emulate_alu_tests(struct kprobe *p, struct pt_regs *regs)
  680. {
  681. insn_3arg_fn_t *i_fn = (insn_3arg_fn_t *)&p->ainsn.insn[0];
  682. kprobe_opcode_t insn = p->opcode;
  683. long ppc = (long)p->addr + 8;
  684. int rn = (insn >> 16) & 0xf;
  685. int rs = (insn >> 8) & 0xf; /* rs/rsv may be invalid, don't care. */
  686. int rm = insn & 0xf;
  687. long rnv = (rn == 15) ? ppc : regs->uregs[rn];
  688. long rmv = (rm == 15) ? ppc : regs->uregs[rm];
  689. long rsv = regs->uregs[rs];
  690. insnslot_3arg_rwflags(rnv, rmv, rsv, &regs->ARM_cpsr, i_fn);
  691. }
  692. static enum kprobe_insn __kprobes
  693. prep_emulate_ldr_str(kprobe_opcode_t insn, struct arch_specific_insn *asi)
  694. {
  695. int not_imm = (insn & (1 << 26)) ? (insn & (1 << 25))
  696. : (~insn & (1 << 22));
  697. if (is_writeback(insn) && is_r15(insn, 16))
  698. return INSN_REJECTED; /* Writeback to PC */
  699. insn &= 0xfff00fff;
  700. insn |= 0x00001000; /* Rn = r0, Rd = r1 */
  701. if (not_imm) {
  702. insn &= ~0xf;
  703. insn |= 2; /* Rm = r2 */
  704. }
  705. asi->insn[0] = insn;
  706. asi->insn_handler = (insn & (1 << 20)) ? emulate_ldr_old : emulate_str_old;
  707. return INSN_GOOD;
  708. }
  709. static enum kprobe_insn __kprobes
  710. prep_emulate_rd12_modify(kprobe_opcode_t insn, struct arch_specific_insn *asi)
  711. {
  712. if (is_r15(insn, 12))
  713. return INSN_REJECTED; /* Rd is PC */
  714. insn &= 0xffff0fff; /* Rd = r0 */
  715. asi->insn[0] = insn;
  716. asi->insn_handler = emulate_rd12_modify;
  717. return INSN_GOOD;
  718. }
  719. static enum kprobe_insn __kprobes
  720. prep_emulate_rd12rn0_modify(kprobe_opcode_t insn,
  721. struct arch_specific_insn *asi)
  722. {
  723. if (is_r15(insn, 12))
  724. return INSN_REJECTED; /* Rd is PC */
  725. insn &= 0xffff0ff0; /* Rd = r0 */
  726. insn |= 0x00000001; /* Rn = r1 */
  727. asi->insn[0] = insn;
  728. asi->insn_handler = emulate_rd12rn0_modify;
  729. return INSN_GOOD;
  730. }
  731. static enum kprobe_insn __kprobes
  732. prep_emulate_rd12rm0(kprobe_opcode_t insn, struct arch_specific_insn *asi)
  733. {
  734. if (is_r15(insn, 12))
  735. return INSN_REJECTED; /* Rd is PC */
  736. insn &= 0xffff0ff0; /* Rd = r0, Rm = r0 */
  737. asi->insn[0] = insn;
  738. asi->insn_handler = emulate_rd12rm0;
  739. return INSN_GOOD;
  740. }
  741. static enum kprobe_insn __kprobes
  742. prep_emulate_rd12rn16rm0_wflags(kprobe_opcode_t insn,
  743. struct arch_specific_insn *asi)
  744. {
  745. if (is_r15(insn, 12))
  746. return INSN_REJECTED; /* Rd is PC */
  747. insn &= 0xfff00ff0; /* Rd = r0, Rn = r0 */
  748. insn |= 0x00000001; /* Rm = r1 */
  749. asi->insn[0] = insn;
  750. asi->insn_handler = emulate_rd12rn16rm0_rwflags;
  751. return INSN_GOOD;
  752. }
  753. static enum kprobe_insn __kprobes
  754. prep_emulate_rd16rs8rm0_wflags(kprobe_opcode_t insn,
  755. struct arch_specific_insn *asi)
  756. {
  757. if (is_r15(insn, 16))
  758. return INSN_REJECTED; /* Rd is PC */
  759. insn &= 0xfff0f0f0; /* Rd = r0, Rs = r0 */
  760. insn |= 0x00000001; /* Rm = r1 */
  761. asi->insn[0] = insn;
  762. asi->insn_handler = emulate_rd16rs8rm0_rwflags;
  763. return INSN_GOOD;
  764. }
  765. static enum kprobe_insn __kprobes
  766. prep_emulate_rd16rn12rs8rm0_wflags(kprobe_opcode_t insn,
  767. struct arch_specific_insn *asi)
  768. {
  769. if (is_r15(insn, 16))
  770. return INSN_REJECTED; /* Rd is PC */
  771. insn &= 0xfff000f0; /* Rd = r0, Rn = r0 */
  772. insn |= 0x00000102; /* Rs = r1, Rm = r2 */
  773. asi->insn[0] = insn;
  774. asi->insn_handler = emulate_rd16rn12rs8rm0_rwflags;
  775. return INSN_GOOD;
  776. }
  777. static enum kprobe_insn __kprobes
  778. prep_emulate_rdhi16rdlo12rs8rm0_wflags(kprobe_opcode_t insn,
  779. struct arch_specific_insn *asi)
  780. {
  781. if (is_r15(insn, 16) || is_r15(insn, 12))
  782. return INSN_REJECTED; /* RdHi or RdLo is PC */
  783. insn &= 0xfff000f0; /* RdHi = r0, RdLo = r1 */
  784. insn |= 0x00001203; /* Rs = r2, Rm = r3 */
  785. asi->insn[0] = insn;
  786. asi->insn_handler = emulate_rdhi16rdlo12rs8rm0_rwflags;
  787. return INSN_GOOD;
  788. }
  789. static void __kprobes
  790. emulate_ldrdstrd(struct kprobe *p, struct pt_regs *regs)
  791. {
  792. kprobe_opcode_t insn = p->opcode;
  793. unsigned long pc = (unsigned long)p->addr + 8;
  794. int rt = (insn >> 12) & 0xf;
  795. int rn = (insn >> 16) & 0xf;
  796. int rm = insn & 0xf;
  797. register unsigned long rtv asm("r0") = regs->uregs[rt];
  798. register unsigned long rt2v asm("r1") = regs->uregs[rt+1];
  799. register unsigned long rnv asm("r2") = (rn == 15) ? pc
  800. : regs->uregs[rn];
  801. register unsigned long rmv asm("r3") = regs->uregs[rm];
  802. __asm__ __volatile__ (
  803. BLX("%[fn]")
  804. : "=r" (rtv), "=r" (rt2v), "=r" (rnv)
  805. : "0" (rtv), "1" (rt2v), "2" (rnv), "r" (rmv),
  806. [fn] "r" (p->ainsn.insn_fn)
  807. : "lr", "memory", "cc"
  808. );
  809. regs->uregs[rt] = rtv;
  810. regs->uregs[rt+1] = rt2v;
  811. if (is_writeback(insn))
  812. regs->uregs[rn] = rnv;
  813. }
  814. static void __kprobes
  815. emulate_ldr(struct kprobe *p, struct pt_regs *regs)
  816. {
  817. kprobe_opcode_t insn = p->opcode;
  818. unsigned long pc = (unsigned long)p->addr + 8;
  819. int rt = (insn >> 12) & 0xf;
  820. int rn = (insn >> 16) & 0xf;
  821. int rm = insn & 0xf;
  822. register unsigned long rtv asm("r0");
  823. register unsigned long rnv asm("r2") = (rn == 15) ? pc
  824. : regs->uregs[rn];
  825. register unsigned long rmv asm("r3") = regs->uregs[rm];
  826. __asm__ __volatile__ (
  827. BLX("%[fn]")
  828. : "=r" (rtv), "=r" (rnv)
  829. : "1" (rnv), "r" (rmv), [fn] "r" (p->ainsn.insn_fn)
  830. : "lr", "memory", "cc"
  831. );
  832. if (rt == 15)
  833. load_write_pc(rtv, regs);
  834. else
  835. regs->uregs[rt] = rtv;
  836. if (is_writeback(insn))
  837. regs->uregs[rn] = rnv;
  838. }
  839. static void __kprobes
  840. emulate_str(struct kprobe *p, struct pt_regs *regs)
  841. {
  842. kprobe_opcode_t insn = p->opcode;
  843. unsigned long rtpc = (unsigned long)p->addr + str_pc_offset;
  844. unsigned long rnpc = (unsigned long)p->addr + 8;
  845. int rt = (insn >> 12) & 0xf;
  846. int rn = (insn >> 16) & 0xf;
  847. int rm = insn & 0xf;
  848. register unsigned long rtv asm("r0") = (rt == 15) ? rtpc
  849. : regs->uregs[rt];
  850. register unsigned long rnv asm("r2") = (rn == 15) ? rnpc
  851. : regs->uregs[rn];
  852. register unsigned long rmv asm("r3") = regs->uregs[rm];
  853. __asm__ __volatile__ (
  854. BLX("%[fn]")
  855. : "=r" (rnv)
  856. : "r" (rtv), "0" (rnv), "r" (rmv), [fn] "r" (p->ainsn.insn_fn)
  857. : "lr", "memory", "cc"
  858. );
  859. if (is_writeback(insn))
  860. regs->uregs[rn] = rnv;
  861. }
  862. static void __kprobes
  863. emulate_rd12rn16rm0rs8_rwflags(struct kprobe *p, struct pt_regs *regs)
  864. {
  865. kprobe_opcode_t insn = p->opcode;
  866. unsigned long pc = (unsigned long)p->addr + 8;
  867. int rd = (insn >> 12) & 0xf;
  868. int rn = (insn >> 16) & 0xf;
  869. int rm = insn & 0xf;
  870. int rs = (insn >> 8) & 0xf;
  871. register unsigned long rdv asm("r0") = regs->uregs[rd];
  872. register unsigned long rnv asm("r2") = (rn == 15) ? pc
  873. : regs->uregs[rn];
  874. register unsigned long rmv asm("r3") = (rm == 15) ? pc
  875. : regs->uregs[rm];
  876. register unsigned long rsv asm("r1") = regs->uregs[rs];
  877. unsigned long cpsr = regs->ARM_cpsr;
  878. __asm__ __volatile__ (
  879. "msr cpsr_fs, %[cpsr] \n\t"
  880. BLX("%[fn]")
  881. "mrs %[cpsr], cpsr \n\t"
  882. : "=r" (rdv), [cpsr] "=r" (cpsr)
  883. : "0" (rdv), "r" (rnv), "r" (rmv), "r" (rsv),
  884. "1" (cpsr), [fn] "r" (p->ainsn.insn_fn)
  885. : "lr", "memory", "cc"
  886. );
  887. if (rd == 15)
  888. alu_write_pc(rdv, regs);
  889. else
  890. regs->uregs[rd] = rdv;
  891. regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
  892. }
  893. static void __kprobes
  894. emulate_rd12rn16rm0_rwflags_nopc(struct kprobe *p, struct pt_regs *regs)
  895. {
  896. kprobe_opcode_t insn = p->opcode;
  897. int rd = (insn >> 12) & 0xf;
  898. int rn = (insn >> 16) & 0xf;
  899. int rm = insn & 0xf;
  900. register unsigned long rdv asm("r0") = regs->uregs[rd];
  901. register unsigned long rnv asm("r2") = regs->uregs[rn];
  902. register unsigned long rmv asm("r3") = regs->uregs[rm];
  903. unsigned long cpsr = regs->ARM_cpsr;
  904. __asm__ __volatile__ (
  905. "msr cpsr_fs, %[cpsr] \n\t"
  906. BLX("%[fn]")
  907. "mrs %[cpsr], cpsr \n\t"
  908. : "=r" (rdv), [cpsr] "=r" (cpsr)
  909. : "0" (rdv), "r" (rnv), "r" (rmv),
  910. "1" (cpsr), [fn] "r" (p->ainsn.insn_fn)
  911. : "lr", "memory", "cc"
  912. );
  913. regs->uregs[rd] = rdv;
  914. regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
  915. }
  916. static void __kprobes
  917. emulate_rd16rn12rm0rs8_rwflags_nopc(struct kprobe *p, struct pt_regs *regs)
  918. {
  919. kprobe_opcode_t insn = p->opcode;
  920. int rd = (insn >> 16) & 0xf;
  921. int rn = (insn >> 12) & 0xf;
  922. int rm = insn & 0xf;
  923. int rs = (insn >> 8) & 0xf;
  924. register unsigned long rdv asm("r2") = regs->uregs[rd];
  925. register unsigned long rnv asm("r0") = regs->uregs[rn];
  926. register unsigned long rmv asm("r3") = regs->uregs[rm];
  927. register unsigned long rsv asm("r1") = regs->uregs[rs];
  928. unsigned long cpsr = regs->ARM_cpsr;
  929. __asm__ __volatile__ (
  930. "msr cpsr_fs, %[cpsr] \n\t"
  931. BLX("%[fn]")
  932. "mrs %[cpsr], cpsr \n\t"
  933. : "=r" (rdv), [cpsr] "=r" (cpsr)
  934. : "0" (rdv), "r" (rnv), "r" (rmv), "r" (rsv),
  935. "1" (cpsr), [fn] "r" (p->ainsn.insn_fn)
  936. : "lr", "memory", "cc"
  937. );
  938. regs->uregs[rd] = rdv;
  939. regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
  940. }
  941. static void __kprobes
  942. emulate_rd12rm0_noflags_nopc(struct kprobe *p, struct pt_regs *regs)
  943. {
  944. kprobe_opcode_t insn = p->opcode;
  945. int rd = (insn >> 12) & 0xf;
  946. int rm = insn & 0xf;
  947. register unsigned long rdv asm("r0") = regs->uregs[rd];
  948. register unsigned long rmv asm("r3") = regs->uregs[rm];
  949. __asm__ __volatile__ (
  950. BLX("%[fn]")
  951. : "=r" (rdv)
  952. : "0" (rdv), "r" (rmv), [fn] "r" (p->ainsn.insn_fn)
  953. : "lr", "memory", "cc"
  954. );
  955. regs->uregs[rd] = rdv;
  956. }
  957. static void __kprobes
  958. emulate_rdlo12rdhi16rn0rm8_rwflags_nopc(struct kprobe *p, struct pt_regs *regs)
  959. {
  960. kprobe_opcode_t insn = p->opcode;
  961. int rdlo = (insn >> 12) & 0xf;
  962. int rdhi = (insn >> 16) & 0xf;
  963. int rn = insn & 0xf;
  964. int rm = (insn >> 8) & 0xf;
  965. register unsigned long rdlov asm("r0") = regs->uregs[rdlo];
  966. register unsigned long rdhiv asm("r2") = regs->uregs[rdhi];
  967. register unsigned long rnv asm("r3") = regs->uregs[rn];
  968. register unsigned long rmv asm("r1") = regs->uregs[rm];
  969. unsigned long cpsr = regs->ARM_cpsr;
  970. __asm__ __volatile__ (
  971. "msr cpsr_fs, %[cpsr] \n\t"
  972. BLX("%[fn]")
  973. "mrs %[cpsr], cpsr \n\t"
  974. : "=r" (rdlov), "=r" (rdhiv), [cpsr] "=r" (cpsr)
  975. : "0" (rdlov), "1" (rdhiv), "r" (rnv), "r" (rmv),
  976. "2" (cpsr), [fn] "r" (p->ainsn.insn_fn)
  977. : "lr", "memory", "cc"
  978. );
  979. regs->uregs[rdlo] = rdlov;
  980. regs->uregs[rdhi] = rdhiv;
  981. regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
  982. }
  983. /*
  984. * For the instruction masking and comparisons in all the "space_*"
  985. * functions below, Do _not_ rearrange the order of tests unless
  986. * you're very, very sure of what you are doing. For the sake of
  987. * efficiency, the masks for some tests sometimes assume other test
  988. * have been done prior to them so the number of patterns to test
  989. * for an instruction set can be as broad as possible to reduce the
  990. * number of tests needed.
  991. */
  992. static const union decode_item arm_1111_table[] = {
  993. /* Unconditional instructions */
  994. /* memory hint 1111 0100 x001 xxxx xxxx xxxx xxxx xxxx */
  995. /* PLDI (immediate) 1111 0100 x101 xxxx xxxx xxxx xxxx xxxx */
  996. /* PLDW (immediate) 1111 0101 x001 xxxx xxxx xxxx xxxx xxxx */
  997. /* PLD (immediate) 1111 0101 x101 xxxx xxxx xxxx xxxx xxxx */
  998. DECODE_SIMULATE (0xfe300000, 0xf4100000, kprobe_simulate_nop),
  999. /* BLX (immediate) 1111 101x xxxx xxxx xxxx xxxx xxxx xxxx */
  1000. DECODE_SIMULATE (0xfe000000, 0xfa000000, simulate_blx1),
  1001. /* CPS 1111 0001 0000 xxx0 xxxx xxxx xx0x xxxx */
  1002. /* SETEND 1111 0001 0000 0001 xxxx xxxx 0000 xxxx */
  1003. /* SRS 1111 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
  1004. /* RFE 1111 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
  1005. /* Coprocessor instructions... */
  1006. /* MCRR2 1111 1100 0100 xxxx xxxx xxxx xxxx xxxx */
  1007. /* MRRC2 1111 1100 0101 xxxx xxxx xxxx xxxx xxxx */
  1008. /* LDC2 1111 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
  1009. /* STC2 1111 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
  1010. /* CDP2 1111 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
  1011. /* MCR2 1111 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
  1012. /* MRC2 1111 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
  1013. /* Other unallocated instructions... */
  1014. DECODE_END
  1015. };
  1016. static const union decode_item arm_cccc_0001_0xx0____0xxx_table[] = {
  1017. /* Miscellaneous instructions */
  1018. /* MRS cpsr cccc 0001 0000 xxxx xxxx xxxx 0000 xxxx */
  1019. DECODE_SIMULATEX(0x0ff000f0, 0x01000000, simulate_mrs,
  1020. REGS(0, NOPC, 0, 0, 0)),
  1021. /* BX cccc 0001 0010 xxxx xxxx xxxx 0001 xxxx */
  1022. DECODE_SIMULATE (0x0ff000f0, 0x01200010, simulate_blx2bx),
  1023. /* BLX (register) cccc 0001 0010 xxxx xxxx xxxx 0011 xxxx */
  1024. DECODE_SIMULATEX(0x0ff000f0, 0x01200030, simulate_blx2bx,
  1025. REGS(0, 0, 0, 0, NOPC)),
  1026. /* CLZ cccc 0001 0110 xxxx xxxx xxxx 0001 xxxx */
  1027. DECODE_EMULATEX (0x0ff000f0, 0x01600010, emulate_rd12rm0_noflags_nopc,
  1028. REGS(0, NOPC, 0, 0, NOPC)),
  1029. /* QADD cccc 0001 0000 xxxx xxxx xxxx 0101 xxxx */
  1030. /* QSUB cccc 0001 0010 xxxx xxxx xxxx 0101 xxxx */
  1031. /* QDADD cccc 0001 0100 xxxx xxxx xxxx 0101 xxxx */
  1032. /* QDSUB cccc 0001 0110 xxxx xxxx xxxx 0101 xxxx */
  1033. DECODE_EMULATEX (0x0f9000f0, 0x01000050, emulate_rd12rn16rm0_rwflags_nopc,
  1034. REGS(NOPC, NOPC, 0, 0, NOPC)),
  1035. /* BXJ cccc 0001 0010 xxxx xxxx xxxx 0010 xxxx */
  1036. /* MSR cccc 0001 0x10 xxxx xxxx xxxx 0000 xxxx */
  1037. /* MRS spsr cccc 0001 0100 xxxx xxxx xxxx 0000 xxxx */
  1038. /* BKPT 1110 0001 0010 xxxx xxxx xxxx 0111 xxxx */
  1039. /* SMC cccc 0001 0110 xxxx xxxx xxxx 0111 xxxx */
  1040. /* And unallocated instructions... */
  1041. DECODE_END
  1042. };
  1043. static const union decode_item arm_cccc_0001_0xx0____1xx0_table[] = {
  1044. /* Halfword multiply and multiply-accumulate */
  1045. /* SMLALxy cccc 0001 0100 xxxx xxxx xxxx 1xx0 xxxx */
  1046. DECODE_EMULATEX (0x0ff00090, 0x01400080, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
  1047. REGS(NOPC, NOPC, NOPC, 0, NOPC)),
  1048. /* SMULWy cccc 0001 0010 xxxx xxxx xxxx 1x10 xxxx */
  1049. DECODE_OR (0x0ff000b0, 0x012000a0),
  1050. /* SMULxy cccc 0001 0110 xxxx xxxx xxxx 1xx0 xxxx */
  1051. DECODE_EMULATEX (0x0ff00090, 0x01600080, emulate_rd16rn12rm0rs8_rwflags_nopc,
  1052. REGS(NOPC, 0, NOPC, 0, NOPC)),
  1053. /* SMLAxy cccc 0001 0000 xxxx xxxx xxxx 1xx0 xxxx */
  1054. DECODE_OR (0x0ff00090, 0x01000080),
  1055. /* SMLAWy cccc 0001 0010 xxxx xxxx xxxx 1x00 xxxx */
  1056. DECODE_EMULATEX (0x0ff000b0, 0x01200080, emulate_rd16rn12rm0rs8_rwflags_nopc,
  1057. REGS(NOPC, NOPC, NOPC, 0, NOPC)),
  1058. DECODE_END
  1059. };
  1060. static const union decode_item arm_cccc_0000_____1001_table[] = {
  1061. /* Multiply and multiply-accumulate */
  1062. /* MUL cccc 0000 0000 xxxx xxxx xxxx 1001 xxxx */
  1063. /* MULS cccc 0000 0001 xxxx xxxx xxxx 1001 xxxx */
  1064. DECODE_EMULATEX (0x0fe000f0, 0x00000090, emulate_rd16rn12rm0rs8_rwflags_nopc,
  1065. REGS(NOPC, 0, NOPC, 0, NOPC)),
  1066. /* MLA cccc 0000 0010 xxxx xxxx xxxx 1001 xxxx */
  1067. /* MLAS cccc 0000 0011 xxxx xxxx xxxx 1001 xxxx */
  1068. DECODE_OR (0x0fe000f0, 0x00200090),
  1069. /* MLS cccc 0000 0110 xxxx xxxx xxxx 1001 xxxx */
  1070. DECODE_EMULATEX (0x0ff000f0, 0x00600090, emulate_rd16rn12rm0rs8_rwflags_nopc,
  1071. REGS(NOPC, NOPC, NOPC, 0, NOPC)),
  1072. /* UMAAL cccc 0000 0100 xxxx xxxx xxxx 1001 xxxx */
  1073. DECODE_OR (0x0ff000f0, 0x00400090),
  1074. /* UMULL cccc 0000 1000 xxxx xxxx xxxx 1001 xxxx */
  1075. /* UMULLS cccc 0000 1001 xxxx xxxx xxxx 1001 xxxx */
  1076. /* UMLAL cccc 0000 1010 xxxx xxxx xxxx 1001 xxxx */
  1077. /* UMLALS cccc 0000 1011 xxxx xxxx xxxx 1001 xxxx */
  1078. /* SMULL cccc 0000 1100 xxxx xxxx xxxx 1001 xxxx */
  1079. /* SMULLS cccc 0000 1101 xxxx xxxx xxxx 1001 xxxx */
  1080. /* SMLAL cccc 0000 1110 xxxx xxxx xxxx 1001 xxxx */
  1081. /* SMLALS cccc 0000 1111 xxxx xxxx xxxx 1001 xxxx */
  1082. DECODE_EMULATEX (0x0f8000f0, 0x00800090, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
  1083. REGS(NOPC, NOPC, NOPC, 0, NOPC)),
  1084. DECODE_END
  1085. };
  1086. static const union decode_item arm_cccc_0001_____1001_table[] = {
  1087. /* Synchronization primitives */
  1088. /* SMP/SWPB cccc 0001 0x00 xxxx xxxx xxxx 1001 xxxx */
  1089. DECODE_EMULATEX (0x0fb000f0, 0x01000090, emulate_rd12rn16rm0_rwflags_nopc,
  1090. REGS(NOPC, NOPC, 0, 0, NOPC)),
  1091. /* LDREX/STREX{,D,B,H} cccc 0001 1xxx xxxx xxxx xxxx 1001 xxxx */
  1092. /* And unallocated instructions... */
  1093. DECODE_END
  1094. };
  1095. static const union decode_item arm_cccc_000x_____1xx1_table[] = {
  1096. /* Extra load/store instructions */
  1097. /* STRHT cccc 0000 xx10 xxxx xxxx xxxx 1011 xxxx */
  1098. /* ??? cccc 0000 xx10 xxxx xxxx xxxx 11x1 xxxx */
  1099. /* LDRHT cccc 0000 xx11 xxxx xxxx xxxx 1011 xxxx */
  1100. /* LDRSBT cccc 0000 xx11 xxxx xxxx xxxx 1101 xxxx */
  1101. /* LDRSHT cccc 0000 xx11 xxxx xxxx xxxx 1111 xxxx */
  1102. DECODE_REJECT (0x0f200090, 0x00200090),
  1103. /* LDRD/STRD lr,pc,{... cccc 000x x0x0 xxxx 111x xxxx 1101 xxxx */
  1104. DECODE_REJECT (0x0e10e0d0, 0x0000e0d0),
  1105. /* LDRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1101 xxxx */
  1106. /* STRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1111 xxxx */
  1107. DECODE_EMULATEX (0x0e5000d0, 0x000000d0, emulate_ldrdstrd,
  1108. REGS(NOPCWB, NOPCX, 0, 0, NOPC)),
  1109. /* LDRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1101 xxxx */
  1110. /* STRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1111 xxxx */
  1111. DECODE_EMULATEX (0x0e5000d0, 0x004000d0, emulate_ldrdstrd,
  1112. REGS(NOPCWB, NOPCX, 0, 0, 0)),
  1113. /* STRH (register) cccc 000x x0x0 xxxx xxxx xxxx 1011 xxxx */
  1114. DECODE_EMULATEX (0x0e5000f0, 0x000000b0, emulate_str,
  1115. REGS(NOPCWB, NOPC, 0, 0, NOPC)),
  1116. /* LDRH (register) cccc 000x x0x1 xxxx xxxx xxxx 1011 xxxx */
  1117. /* LDRSB (register) cccc 000x x0x1 xxxx xxxx xxxx 1101 xxxx */
  1118. /* LDRSH (register) cccc 000x x0x1 xxxx xxxx xxxx 1111 xxxx */
  1119. DECODE_EMULATEX (0x0e500090, 0x00100090, emulate_ldr,
  1120. REGS(NOPCWB, NOPC, 0, 0, NOPC)),
  1121. /* STRH (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1011 xxxx */
  1122. DECODE_EMULATEX (0x0e5000f0, 0x004000b0, emulate_str,
  1123. REGS(NOPCWB, NOPC, 0, 0, 0)),
  1124. /* LDRH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1011 xxxx */
  1125. /* LDRSB (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1101 xxxx */
  1126. /* LDRSH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1111 xxxx */
  1127. DECODE_EMULATEX (0x0e500090, 0x00500090, emulate_ldr,
  1128. REGS(NOPCWB, NOPC, 0, 0, 0)),
  1129. DECODE_END
  1130. };
  1131. static const union decode_item arm_cccc_000x_table[] = {
  1132. /* Data-processing (register) */
  1133. /* <op>S PC, ... cccc 000x xxx1 xxxx 1111 xxxx xxxx xxxx */
  1134. DECODE_REJECT (0x0e10f000, 0x0010f000),
  1135. /* MOV IP, SP 1110 0001 1010 0000 1100 0000 0000 1101 */
  1136. DECODE_SIMULATE (0xffffffff, 0xe1a0c00d, simulate_mov_ipsp),
  1137. /* TST (register) cccc 0001 0001 xxxx xxxx xxxx xxx0 xxxx */
  1138. /* TEQ (register) cccc 0001 0011 xxxx xxxx xxxx xxx0 xxxx */
  1139. /* CMP (register) cccc 0001 0101 xxxx xxxx xxxx xxx0 xxxx */
  1140. /* CMN (register) cccc 0001 0111 xxxx xxxx xxxx xxx0 xxxx */
  1141. DECODE_EMULATEX (0x0f900010, 0x01100000, emulate_rd12rn16rm0rs8_rwflags,
  1142. REGS(ANY, 0, 0, 0, ANY)),
  1143. /* MOV (register) cccc 0001 101x xxxx xxxx xxxx xxx0 xxxx */
  1144. /* MVN (register) cccc 0001 111x xxxx xxxx xxxx xxx0 xxxx */
  1145. DECODE_EMULATEX (0x0fa00010, 0x01a00000, emulate_rd12rn16rm0rs8_rwflags,
  1146. REGS(0, ANY, 0, 0, ANY)),
  1147. /* AND (register) cccc 0000 000x xxxx xxxx xxxx xxx0 xxxx */
  1148. /* EOR (register) cccc 0000 001x xxxx xxxx xxxx xxx0 xxxx */
  1149. /* SUB (register) cccc 0000 010x xxxx xxxx xxxx xxx0 xxxx */
  1150. /* RSB (register) cccc 0000 011x xxxx xxxx xxxx xxx0 xxxx */
  1151. /* ADD (register) cccc 0000 100x xxxx xxxx xxxx xxx0 xxxx */
  1152. /* ADC (register) cccc 0000 101x xxxx xxxx xxxx xxx0 xxxx */
  1153. /* SBC (register) cccc 0000 110x xxxx xxxx xxxx xxx0 xxxx */
  1154. /* RSC (register) cccc 0000 111x xxxx xxxx xxxx xxx0 xxxx */
  1155. /* ORR (register) cccc 0001 100x xxxx xxxx xxxx xxx0 xxxx */
  1156. /* BIC (register) cccc 0001 110x xxxx xxxx xxxx xxx0 xxxx */
  1157. DECODE_EMULATEX (0x0e000010, 0x00000000, emulate_rd12rn16rm0rs8_rwflags,
  1158. REGS(ANY, ANY, 0, 0, ANY)),
  1159. /* TST (reg-shift reg) cccc 0001 0001 xxxx xxxx xxxx 0xx1 xxxx */
  1160. /* TEQ (reg-shift reg) cccc 0001 0011 xxxx xxxx xxxx 0xx1 xxxx */
  1161. /* CMP (reg-shift reg) cccc 0001 0101 xxxx xxxx xxxx 0xx1 xxxx */
  1162. /* CMN (reg-shift reg) cccc 0001 0111 xxxx xxxx xxxx 0xx1 xxxx */
  1163. DECODE_EMULATEX (0x0f900090, 0x01100010, emulate_rd12rn16rm0rs8_rwflags,
  1164. REGS(ANY, 0, NOPC, 0, ANY)),
  1165. /* MOV (reg-shift reg) cccc 0001 101x xxxx xxxx xxxx 0xx1 xxxx */
  1166. /* MVN (reg-shift reg) cccc 0001 111x xxxx xxxx xxxx 0xx1 xxxx */
  1167. DECODE_EMULATEX (0x0fa00090, 0x01a00010, emulate_rd12rn16rm0rs8_rwflags,
  1168. REGS(0, ANY, NOPC, 0, ANY)),
  1169. /* AND (reg-shift reg) cccc 0000 000x xxxx xxxx xxxx 0xx1 xxxx */
  1170. /* EOR (reg-shift reg) cccc 0000 001x xxxx xxxx xxxx 0xx1 xxxx */
  1171. /* SUB (reg-shift reg) cccc 0000 010x xxxx xxxx xxxx 0xx1 xxxx */
  1172. /* RSB (reg-shift reg) cccc 0000 011x xxxx xxxx xxxx 0xx1 xxxx */
  1173. /* ADD (reg-shift reg) cccc 0000 100x xxxx xxxx xxxx 0xx1 xxxx */
  1174. /* ADC (reg-shift reg) cccc 0000 101x xxxx xxxx xxxx 0xx1 xxxx */
  1175. /* SBC (reg-shift reg) cccc 0000 110x xxxx xxxx xxxx 0xx1 xxxx */
  1176. /* RSC (reg-shift reg) cccc 0000 111x xxxx xxxx xxxx 0xx1 xxxx */
  1177. /* ORR (reg-shift reg) cccc 0001 100x xxxx xxxx xxxx 0xx1 xxxx */
  1178. /* BIC (reg-shift reg) cccc 0001 110x xxxx xxxx xxxx 0xx1 xxxx */
  1179. DECODE_EMULATEX (0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags,
  1180. REGS(ANY, ANY, NOPC, 0, ANY)),
  1181. DECODE_END
  1182. };
  1183. static const union decode_item arm_cccc_001x_table[] = {
  1184. /* Data-processing (immediate) */
  1185. /* MOVW cccc 0011 0000 xxxx xxxx xxxx xxxx xxxx */
  1186. /* MOVT cccc 0011 0100 xxxx xxxx xxxx xxxx xxxx */
  1187. DECODE_EMULATEX (0x0fb00000, 0x03000000, emulate_rd12rm0_noflags_nopc,
  1188. REGS(0, NOPC, 0, 0, 0)),
  1189. /* YIELD cccc 0011 0010 0000 xxxx xxxx 0000 0001 */
  1190. DECODE_OR (0x0fff00ff, 0x03200001),
  1191. /* SEV cccc 0011 0010 0000 xxxx xxxx 0000 0100 */
  1192. DECODE_EMULATE (0x0fff00ff, 0x03200004, kprobe_emulate_none),
  1193. /* NOP cccc 0011 0010 0000 xxxx xxxx 0000 0000 */
  1194. /* WFE cccc 0011 0010 0000 xxxx xxxx 0000 0010 */
  1195. /* WFI cccc 0011 0010 0000 xxxx xxxx 0000 0011 */
  1196. DECODE_SIMULATE (0x0fff00fc, 0x03200000, kprobe_simulate_nop),
  1197. /* DBG cccc 0011 0010 0000 xxxx xxxx ffff xxxx */
  1198. /* unallocated hints cccc 0011 0010 0000 xxxx xxxx xxxx xxxx */
  1199. /* MSR (immediate) cccc 0011 0x10 xxxx xxxx xxxx xxxx xxxx */
  1200. DECODE_REJECT (0x0fb00000, 0x03200000),
  1201. /* <op>S PC, ... cccc 001x xxx1 xxxx 1111 xxxx xxxx xxxx */
  1202. DECODE_REJECT (0x0e10f000, 0x0210f000),
  1203. /* TST (immediate) cccc 0011 0001 xxxx xxxx xxxx xxxx xxxx */
  1204. /* TEQ (immediate) cccc 0011 0011 xxxx xxxx xxxx xxxx xxxx */
  1205. /* CMP (immediate) cccc 0011 0101 xxxx xxxx xxxx xxxx xxxx */
  1206. /* CMN (immediate) cccc 0011 0111 xxxx xxxx xxxx xxxx xxxx */
  1207. DECODE_EMULATEX (0x0f900000, 0x03100000, emulate_rd12rn16rm0rs8_rwflags,
  1208. REGS(ANY, 0, 0, 0, 0)),
  1209. /* MOV (immediate) cccc 0011 101x xxxx xxxx xxxx xxxx xxxx */
  1210. /* MVN (immediate) cccc 0011 111x xxxx xxxx xxxx xxxx xxxx */
  1211. DECODE_EMULATEX (0x0fa00000, 0x03a00000, emulate_rd12rn16rm0rs8_rwflags,
  1212. REGS(0, ANY, 0, 0, 0)),
  1213. /* AND (immediate) cccc 0010 000x xxxx xxxx xxxx xxxx xxxx */
  1214. /* EOR (immediate) cccc 0010 001x xxxx xxxx xxxx xxxx xxxx */
  1215. /* SUB (immediate) cccc 0010 010x xxxx xxxx xxxx xxxx xxxx */
  1216. /* RSB (immediate) cccc 0010 011x xxxx xxxx xxxx xxxx xxxx */
  1217. /* ADD (immediate) cccc 0010 100x xxxx xxxx xxxx xxxx xxxx */
  1218. /* ADC (immediate) cccc 0010 101x xxxx xxxx xxxx xxxx xxxx */
  1219. /* SBC (immediate) cccc 0010 110x xxxx xxxx xxxx xxxx xxxx */
  1220. /* RSC (immediate) cccc 0010 111x xxxx xxxx xxxx xxxx xxxx */
  1221. /* ORR (immediate) cccc 0011 100x xxxx xxxx xxxx xxxx xxxx */
  1222. /* BIC (immediate) cccc 0011 110x xxxx xxxx xxxx xxxx xxxx */
  1223. DECODE_EMULATEX (0x0e000000, 0x02000000, emulate_rd12rn16rm0rs8_rwflags,
  1224. REGS(ANY, ANY, 0, 0, 0)),
  1225. DECODE_END
  1226. };
  1227. static const union decode_item arm_cccc_0110_____xxx1_table[] = {
  1228. /* Media instructions */
  1229. /* SEL cccc 0110 1000 xxxx xxxx xxxx 1011 xxxx */
  1230. DECODE_EMULATEX (0x0ff000f0, 0x068000b0, emulate_rd12rn16rm0_rwflags_nopc,
  1231. REGS(NOPC, NOPC, 0, 0, NOPC)),
  1232. /* SSAT cccc 0110 101x xxxx xxxx xxxx xx01 xxxx */
  1233. /* USAT cccc 0110 111x xxxx xxxx xxxx xx01 xxxx */
  1234. DECODE_OR(0x0fa00030, 0x06a00010),
  1235. /* SSAT16 cccc 0110 1010 xxxx xxxx xxxx 0011 xxxx */
  1236. /* USAT16 cccc 0110 1110 xxxx xxxx xxxx 0011 xxxx */
  1237. DECODE_EMULATEX (0x0fb000f0, 0x06a00030, emulate_rd12rn16rm0_rwflags_nopc,
  1238. REGS(0, NOPC, 0, 0, NOPC)),
  1239. /* REV cccc 0110 1011 xxxx xxxx xxxx 0011 xxxx */
  1240. /* REV16 cccc 0110 1011 xxxx xxxx xxxx 1011 xxxx */
  1241. /* RBIT cccc 0110 1111 xxxx xxxx xxxx 0011 xxxx */
  1242. /* REVSH cccc 0110 1111 xxxx xxxx xxxx 1011 xxxx */
  1243. DECODE_EMULATEX (0x0fb00070, 0x06b00030, emulate_rd12rm0_noflags_nopc,
  1244. REGS(0, NOPC, 0, 0, NOPC)),
  1245. /* ??? cccc 0110 0x00 xxxx xxxx xxxx xxx1 xxxx */
  1246. DECODE_REJECT (0x0fb00010, 0x06000010),
  1247. /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1011 xxxx */
  1248. DECODE_REJECT (0x0f8000f0, 0x060000b0),
  1249. /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1101 xxxx */
  1250. DECODE_REJECT (0x0f8000f0, 0x060000d0),
  1251. /* SADD16 cccc 0110 0001 xxxx xxxx xxxx 0001 xxxx */
  1252. /* SADDSUBX cccc 0110 0001 xxxx xxxx xxxx 0011 xxxx */
  1253. /* SSUBADDX cccc 0110 0001 xxxx xxxx xxxx 0101 xxxx */
  1254. /* SSUB16 cccc 0110 0001 xxxx xxxx xxxx 0111 xxxx */
  1255. /* SADD8 cccc 0110 0001 xxxx xxxx xxxx 1001 xxxx */
  1256. /* SSUB8 cccc 0110 0001 xxxx xxxx xxxx 1111 xxxx */
  1257. /* QADD16 cccc 0110 0010 xxxx xxxx xxxx 0001 xxxx */
  1258. /* QADDSUBX cccc 0110 0010 xxxx xxxx xxxx 0011 xxxx */
  1259. /* QSUBADDX cccc 0110 0010 xxxx xxxx xxxx 0101 xxxx */
  1260. /* QSUB16 cccc 0110 0010 xxxx xxxx xxxx 0111 xxxx */
  1261. /* QADD8 cccc 0110 0010 xxxx xxxx xxxx 1001 xxxx */
  1262. /* QSUB8 cccc 0110 0010 xxxx xxxx xxxx 1111 xxxx */
  1263. /* SHADD16 cccc 0110 0011 xxxx xxxx xxxx 0001 xxxx */
  1264. /* SHADDSUBX cccc 0110 0011 xxxx xxxx xxxx 0011 xxxx */
  1265. /* SHSUBADDX cccc 0110 0011 xxxx xxxx xxxx 0101 xxxx */
  1266. /* SHSUB16 cccc 0110 0011 xxxx xxxx xxxx 0111 xxxx */
  1267. /* SHADD8 cccc 0110 0011 xxxx xxxx xxxx 1001 xxxx */
  1268. /* SHSUB8 cccc 0110 0011 xxxx xxxx xxxx 1111 xxxx */
  1269. /* UADD16 cccc 0110 0101 xxxx xxxx xxxx 0001 xxxx */
  1270. /* UADDSUBX cccc 0110 0101 xxxx xxxx xxxx 0011 xxxx */
  1271. /* USUBADDX cccc 0110 0101 xxxx xxxx xxxx 0101 xxxx */
  1272. /* USUB16 cccc 0110 0101 xxxx xxxx xxxx 0111 xxxx */
  1273. /* UADD8 cccc 0110 0101 xxxx xxxx xxxx 1001 xxxx */
  1274. /* USUB8 cccc 0110 0101 xxxx xxxx xxxx 1111 xxxx */
  1275. /* UQADD16 cccc 0110 0110 xxxx xxxx xxxx 0001 xxxx */
  1276. /* UQADDSUBX cccc 0110 0110 xxxx xxxx xxxx 0011 xxxx */
  1277. /* UQSUBADDX cccc 0110 0110 xxxx xxxx xxxx 0101 xxxx */
  1278. /* UQSUB16 cccc 0110 0110 xxxx xxxx xxxx 0111 xxxx */
  1279. /* UQADD8 cccc 0110 0110 xxxx xxxx xxxx 1001 xxxx */
  1280. /* UQSUB8 cccc 0110 0110 xxxx xxxx xxxx 1111 xxxx */
  1281. /* UHADD16 cccc 0110 0111 xxxx xxxx xxxx 0001 xxxx */
  1282. /* UHADDSUBX cccc 0110 0111 xxxx xxxx xxxx 0011 xxxx */
  1283. /* UHSUBADDX cccc 0110 0111 xxxx xxxx xxxx 0101 xxxx */
  1284. /* UHSUB16 cccc 0110 0111 xxxx xxxx xxxx 0111 xxxx */
  1285. /* UHADD8 cccc 0110 0111 xxxx xxxx xxxx 1001 xxxx */
  1286. /* UHSUB8 cccc 0110 0111 xxxx xxxx xxxx 1111 xxxx */
  1287. DECODE_EMULATEX (0x0f800010, 0x06000010, emulate_rd12rn16rm0_rwflags_nopc,
  1288. REGS(NOPC, NOPC, 0, 0, NOPC)),
  1289. /* PKHBT cccc 0110 1000 xxxx xxxx xxxx x001 xxxx */
  1290. /* PKHTB cccc 0110 1000 xxxx xxxx xxxx x101 xxxx */
  1291. DECODE_EMULATEX (0x0ff00030, 0x06800010, emulate_rd12rn16rm0_rwflags_nopc,
  1292. REGS(NOPC, NOPC, 0, 0, NOPC)),
  1293. /* ??? cccc 0110 1001 xxxx xxxx xxxx 0111 xxxx */
  1294. /* ??? cccc 0110 1101 xxxx xxxx xxxx 0111 xxxx */
  1295. DECODE_REJECT (0x0fb000f0, 0x06900070),
  1296. /* SXTB16 cccc 0110 1000 1111 xxxx xxxx 0111 xxxx */
  1297. /* SXTB cccc 0110 1010 1111 xxxx xxxx 0111 xxxx */
  1298. /* SXTH cccc 0110 1011 1111 xxxx xxxx 0111 xxxx */
  1299. /* UXTB16 cccc 0110 1100 1111 xxxx xxxx 0111 xxxx */
  1300. /* UXTB cccc 0110 1110 1111 xxxx xxxx 0111 xxxx */
  1301. /* UXTH cccc 0110 1111 1111 xxxx xxxx 0111 xxxx */
  1302. DECODE_EMULATEX (0x0f8f00f0, 0x068f0070, emulate_rd12rm0_noflags_nopc,
  1303. REGS(0, NOPC, 0, 0, NOPC)),
  1304. /* SXTAB16 cccc 0110 1000 xxxx xxxx xxxx 0111 xxxx */
  1305. /* SXTAB cccc 0110 1010 xxxx xxxx xxxx 0111 xxxx */
  1306. /* SXTAH cccc 0110 1011 xxxx xxxx xxxx 0111 xxxx */
  1307. /* UXTAB16 cccc 0110 1100 xxxx xxxx xxxx 0111 xxxx */
  1308. /* UXTAB cccc 0110 1110 xxxx xxxx xxxx 0111 xxxx */
  1309. /* UXTAH cccc 0110 1111 xxxx xxxx xxxx 0111 xxxx */
  1310. DECODE_EMULATEX (0x0f8000f0, 0x06800070, emulate_rd12rn16rm0_rwflags_nopc,
  1311. REGS(NOPCX, NOPC, 0, 0, NOPC)),
  1312. DECODE_END
  1313. };
  1314. static const union decode_item arm_cccc_0111_____xxx1_table[] = {
  1315. /* Media instructions */
  1316. /* UNDEFINED cccc 0111 1111 xxxx xxxx xxxx 1111 xxxx */
  1317. DECODE_REJECT (0x0ff000f0, 0x07f000f0),
  1318. /* SMLALD cccc 0111 0100 xxxx xxxx xxxx 00x1 xxxx */
  1319. /* SMLSLD cccc 0111 0100 xxxx xxxx xxxx 01x1 xxxx */
  1320. DECODE_EMULATEX (0x0ff00090, 0x07400010, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
  1321. REGS(NOPC, NOPC, NOPC, 0, NOPC)),
  1322. /* SMUAD cccc 0111 0000 xxxx 1111 xxxx 00x1 xxxx */
  1323. /* SMUSD cccc 0111 0000 xxxx 1111 xxxx 01x1 xxxx */
  1324. DECODE_OR (0x0ff0f090, 0x0700f010),
  1325. /* SMMUL cccc 0111 0101 xxxx 1111 xxxx 00x1 xxxx */
  1326. DECODE_OR (0x0ff0f0d0, 0x0750f010),
  1327. /* USAD8 cccc 0111 1000 xxxx 1111 xxxx 0001 xxxx */
  1328. DECODE_EMULATEX (0x0ff0f0f0, 0x0780f010, emulate_rd16rn12rm0rs8_rwflags_nopc,
  1329. REGS(NOPC, 0, NOPC, 0, NOPC)),
  1330. /* SMLAD cccc 0111 0000 xxxx xxxx xxxx 00x1 xxxx */
  1331. /* SMLSD cccc 0111 0000 xxxx xxxx xxxx 01x1 xxxx */
  1332. DECODE_OR (0x0ff00090, 0x07000010),
  1333. /* SMMLA cccc 0111 0101 xxxx xxxx xxxx 00x1 xxxx */
  1334. DECODE_OR (0x0ff000d0, 0x07500010),
  1335. /* USADA8 cccc 0111 1000 xxxx xxxx xxxx 0001 xxxx */
  1336. DECODE_EMULATEX (0x0ff000f0, 0x07800010, emulate_rd16rn12rm0rs8_rwflags_nopc,
  1337. REGS(NOPC, NOPCX, NOPC, 0, NOPC)),
  1338. /* SMMLS cccc 0111 0101 xxxx xxxx xxxx 11x1 xxxx */
  1339. DECODE_EMULATEX (0x0ff000d0, 0x075000d0, emulate_rd16rn12rm0rs8_rwflags_nopc,
  1340. REGS(NOPC, NOPC, NOPC, 0, NOPC)),
  1341. /* SBFX cccc 0111 101x xxxx xxxx xxxx x101 xxxx */
  1342. /* UBFX cccc 0111 111x xxxx xxxx xxxx x101 xxxx */
  1343. DECODE_EMULATEX (0x0fa00070, 0x07a00050, emulate_rd12rm0_noflags_nopc,
  1344. REGS(0, NOPC, 0, 0, NOPC)),
  1345. /* BFC cccc 0111 110x xxxx xxxx xxxx x001 1111 */
  1346. DECODE_EMULATEX (0x0fe0007f, 0x07c0001f, emulate_rd12rm0_noflags_nopc,
  1347. REGS(0, NOPC, 0, 0, 0)),
  1348. /* BFI cccc 0111 110x xxxx xxxx xxxx x001 xxxx */
  1349. DECODE_EMULATEX (0x0fe00070, 0x07c00010, emulate_rd12rm0_noflags_nopc,
  1350. REGS(0, NOPC, 0, 0, NOPCX)),
  1351. DECODE_END
  1352. };
  1353. static const union decode_item arm_cccc_01xx_table[] = {
  1354. /* Load/store word and unsigned byte */
  1355. /* LDRB/STRB pc,[...] cccc 01xx x0xx xxxx xxxx xxxx xxxx xxxx */
  1356. DECODE_REJECT (0x0c40f000, 0x0440f000),
  1357. /* STRT cccc 01x0 x010 xxxx xxxx xxxx xxxx xxxx */
  1358. /* LDRT cccc 01x0 x011 xxxx xxxx xxxx xxxx xxxx */
  1359. /* STRBT cccc 01x0 x110 xxxx xxxx xxxx xxxx xxxx */
  1360. /* LDRBT cccc 01x0 x111 xxxx xxxx xxxx xxxx xxxx */
  1361. DECODE_REJECT (0x0d200000, 0x04200000),
  1362. /* STR (immediate) cccc 010x x0x0 xxxx xxxx xxxx xxxx xxxx */
  1363. /* STRB (immediate) cccc 010x x1x0 xxxx xxxx xxxx xxxx xxxx */
  1364. DECODE_EMULATEX (0x0e100000, 0x04000000, emulate_str,
  1365. REGS(NOPCWB, ANY, 0, 0, 0)),
  1366. /* LDR (immediate) cccc 010x x0x1 xxxx xxxx xxxx xxxx xxxx */
  1367. /* LDRB (immediate) cccc 010x x1x1 xxxx xxxx xxxx xxxx xxxx */
  1368. DECODE_EMULATEX (0x0e100000, 0x04100000, emulate_ldr,
  1369. REGS(NOPCWB, ANY, 0, 0, 0)),
  1370. /* STR (register) cccc 011x x0x0 xxxx xxxx xxxx xxxx xxxx */
  1371. /* STRB (register) cccc 011x x1x0 xxxx xxxx xxxx xxxx xxxx */
  1372. DECODE_EMULATEX (0x0e100000, 0x06000000, emulate_str,
  1373. REGS(NOPCWB, ANY, 0, 0, NOPC)),
  1374. /* LDR (register) cccc 011x x0x1 xxxx xxxx xxxx xxxx xxxx */
  1375. /* LDRB (register) cccc 011x x1x1 xxxx xxxx xxxx xxxx xxxx */
  1376. DECODE_EMULATEX (0x0e100000, 0x06100000, emulate_ldr,
  1377. REGS(NOPCWB, ANY, 0, 0, NOPC)),
  1378. DECODE_END
  1379. };
  1380. static const union decode_item arm_cccc_100x_table[] = {
  1381. /* Block data transfer instructions */
  1382. /* LDM cccc 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
  1383. /* STM cccc 100x x0x0 xxxx xxxx xxxx xxxx xxxx */
  1384. DECODE_CUSTOM (0x0e400000, 0x08000000, kprobe_decode_ldmstm),
  1385. /* STM (user registers) cccc 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
  1386. /* LDM (user registers) cccc 100x x1x1 xxxx 0xxx xxxx xxxx xxxx */
  1387. /* LDM (exception ret) cccc 100x x1x1 xxxx 1xxx xxxx xxxx xxxx */
  1388. DECODE_END
  1389. };
  1390. const union decode_item kprobe_decode_arm_table[] = {
  1391. /*
  1392. * Unconditional instructions
  1393. * 1111 xxxx xxxx xxxx xxxx xxxx xxxx xxxx
  1394. */
  1395. DECODE_TABLE (0xf0000000, 0xf0000000, arm_1111_table),
  1396. /*
  1397. * Miscellaneous instructions
  1398. * cccc 0001 0xx0 xxxx xxxx xxxx 0xxx xxxx
  1399. */
  1400. DECODE_TABLE (0x0f900080, 0x01000000, arm_cccc_0001_0xx0____0xxx_table),
  1401. /*
  1402. * Halfword multiply and multiply-accumulate
  1403. * cccc 0001 0xx0 xxxx xxxx xxxx 1xx0 xxxx
  1404. */
  1405. DECODE_TABLE (0x0f900090, 0x01000080, arm_cccc_0001_0xx0____1xx0_table),
  1406. /*
  1407. * Multiply and multiply-accumulate
  1408. * cccc 0000 xxxx xxxx xxxx xxxx 1001 xxxx
  1409. */
  1410. DECODE_TABLE (0x0f0000f0, 0x00000090, arm_cccc_0000_____1001_table),
  1411. /*
  1412. * Synchronization primitives
  1413. * cccc 0001 xxxx xxxx xxxx xxxx 1001 xxxx
  1414. */
  1415. DECODE_TABLE (0x0f0000f0, 0x01000090, arm_cccc_0001_____1001_table),
  1416. /*
  1417. * Extra load/store instructions
  1418. * cccc 000x xxxx xxxx xxxx xxxx 1xx1 xxxx
  1419. */
  1420. DECODE_TABLE (0x0e000090, 0x00000090, arm_cccc_000x_____1xx1_table),
  1421. /*
  1422. * Data-processing (register)
  1423. * cccc 000x xxxx xxxx xxxx xxxx xxx0 xxxx
  1424. * Data-processing (register-shifted register)
  1425. * cccc 000x xxxx xxxx xxxx xxxx 0xx1 xxxx
  1426. */
  1427. DECODE_TABLE (0x0e000000, 0x00000000, arm_cccc_000x_table),
  1428. /*
  1429. * Data-processing (immediate)
  1430. * cccc 001x xxxx xxxx xxxx xxxx xxxx xxxx
  1431. */
  1432. DECODE_TABLE (0x0e000000, 0x02000000, arm_cccc_001x_table),
  1433. /*
  1434. * Media instructions
  1435. * cccc 011x xxxx xxxx xxxx xxxx xxx1 xxxx
  1436. */
  1437. DECODE_TABLE (0x0f000010, 0x06000010, arm_cccc_0110_____xxx1_table),
  1438. DECODE_TABLE (0x0f000010, 0x07000010, arm_cccc_0111_____xxx1_table),
  1439. /*
  1440. * Load/store word and unsigned byte
  1441. * cccc 01xx xxxx xxxx xxxx xxxx xxxx xxxx
  1442. */
  1443. DECODE_TABLE (0x0c000000, 0x04000000, arm_cccc_01xx_table),
  1444. /*
  1445. * Block data transfer instructions
  1446. * cccc 100x xxxx xxxx xxxx xxxx xxxx xxxx
  1447. */
  1448. DECODE_TABLE (0x0e000000, 0x08000000, arm_cccc_100x_table),
  1449. /* B cccc 1010 xxxx xxxx xxxx xxxx xxxx xxxx */
  1450. /* BL cccc 1011 xxxx xxxx xxxx xxxx xxxx xxxx */
  1451. DECODE_SIMULATE (0x0e000000, 0x0a000000, simulate_bbl),
  1452. /*
  1453. * Supervisor Call, and coprocessor instructions
  1454. */
  1455. /* MCRR cccc 1100 0100 xxxx xxxx xxxx xxxx xxxx */
  1456. /* MRRC cccc 1100 0101 xxxx xxxx xxxx xxxx xxxx */
  1457. /* LDC cccc 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
  1458. /* STC cccc 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
  1459. /* CDP cccc 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
  1460. /* MCR cccc 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
  1461. /* MRC cccc 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
  1462. /* SVC cccc 1111 xxxx xxxx xxxx xxxx xxxx xxxx */
  1463. DECODE_REJECT (0x0c000000, 0x0c000000),
  1464. DECODE_END
  1465. };
  1466. static void __kprobes arm_singlestep(struct kprobe *p, struct pt_regs *regs)
  1467. {
  1468. regs->ARM_pc += 4;
  1469. p->ainsn.insn_handler(p, regs);
  1470. }
  1471. /* Return:
  1472. * INSN_REJECTED If instruction is one not allowed to kprobe,
  1473. * INSN_GOOD If instruction is supported and uses instruction slot,
  1474. * INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot.
  1475. *
  1476. * For instructions we don't want to kprobe (INSN_REJECTED return result):
  1477. * These are generally ones that modify the processor state making
  1478. * them "hard" to simulate such as switches processor modes or
  1479. * make accesses in alternate modes. Any of these could be simulated
  1480. * if the work was put into it, but low return considering they
  1481. * should also be very rare.
  1482. */
  1483. enum kprobe_insn __kprobes
  1484. arm_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi)
  1485. {
  1486. asi->insn_singlestep = arm_singlestep;
  1487. asi->insn_check_cc = kprobe_condition_checks[insn>>28];
  1488. return kprobe_decode_insn(insn, asi, kprobe_decode_arm_table, false);
  1489. }