projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| b21d55e9 RV |
1 | #include <linux/kernel.h> |
| 2 | #include <linux/kprobes.h> | |
| 3 | #include <linux/stop_machine.h> | |
| 4 | ||
| 5 | #include <asm/cacheflush.h> | |
| 6 | #include <asm/smp_plat.h> | |
| 7 | #include <asm/opcodes.h> | |
| 8 | ||
| 9 | #include "patch.h" | |
| 10 | ||
| 11 | struct patch { | |
| 12 | void *addr; | |
| 13 | unsigned int insn; | |
| 14 | }; | |
| 15 | ||
| 16 | void __kprobes __patch_text(void *addr, unsigned int insn) | |
| 17 | { | |
| 18 | bool thumb2 = IS_ENABLED(CONFIG_THUMB2_KERNEL); | |
| 19 | int size; | |
| 20 | ||
| 21 | if (thumb2 && __opcode_is_thumb16(insn)) { | |
| 22 | *(u16 *)addr = __opcode_to_mem_thumb16(insn); | |
| 23 | size = sizeof(u16); | |
| 24 | } else if (thumb2 && ((uintptr_t)addr & 2)) { | |
| 25 | u16 first = __opcode_thumb32_first(insn); | |
| 26 | u16 second = __opcode_thumb32_second(insn); | |
| 27 | u16 *addrh = addr; | |
| 28 | ||
| 29 | addrh[0] = __opcode_to_mem_thumb16(first); | |
| 30 | addrh[1] = __opcode_to_mem_thumb16(second); | |
| 31 | ||
| 32 | size = sizeof(u32); | |
| 33 | } else { | |
| 34 | if (thumb2) | |
| 35 | insn = __opcode_to_mem_thumb32(insn); | |
| 36 | else | |
| 37 | insn = __opcode_to_mem_arm(insn); | |
| 38 | ||
| 39 | *(u32 *)addr = insn; | |
| 40 | size = sizeof(u32); | |
| 41 | } | |
| 42 | ||
| 43 | flush_icache_range((uintptr_t)(addr), | |
| 44 | (uintptr_t)(addr) + size); | |
| 45 | } | |
| 46 | ||
| 47 | static int __kprobes patch_text_stop_machine(void *data) | |
| 48 | { | |
| 49 | struct patch *patch = data; | |
| 50 | ||
| 51 | __patch_text(patch->addr, patch->insn); | |
| 52 | ||
| 53 | return 0; | |
| 54 | } | |
| 55 | ||
| 56 | void __kprobes patch_text(void *addr, unsigned int insn) | |
| 57 | { | |
| 58 | struct patch patch = { | |
| 59 | .addr = addr, | |
| 60 | .insn = insn, | |
| 61 | }; | |
| 62 | ||
| 63 | if (cache_ops_need_broadcast()) { | |
| 64 | stop_machine(patch_text_stop_machine, &patch, cpu_online_mask); | |
| 65 | } else { | |
| 66 | bool straddles_word = IS_ENABLED(CONFIG_THUMB2_KERNEL) | |
| 67 | && __opcode_is_thumb32(insn) | |
| 68 | && ((uintptr_t)addr & 2); | |
| 69 | ||
| 70 | if (straddles_word) | |
| 71 | stop_machine(patch_text_stop_machine, &patch, NULL); | |
| 72 | else | |
| 73 | __patch_text(addr, insn); | |
| 74 | } | |
| 75 | } |