1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 | // SPDX-License-Identifier: GPL-2.0 /* * Common helper functions for kprobes and uprobes * * Copyright IBM Corp. 2014 */ #include <linux/errno.h> #include <asm/kprobes.h> #include <asm/dis.h> int probe_is_prohibited_opcode(u16 *insn) { if (!is_known_insn((unsigned char *)insn)) return -EINVAL; switch (insn[0] >> 8) { case 0x0c: /* bassm */ case 0x0b: /* bsm */ case 0x83: /* diag */ case 0x44: /* ex */ case 0xac: /* stnsm */ case 0xad: /* stosm */ return -EINVAL; case 0xc6: switch (insn[0] & 0x0f) { case 0x00: /* exrl */ return -EINVAL; } } switch (insn[0]) { case 0x0101: /* pr */ case 0xb25a: /* bsa */ case 0xb240: /* bakr */ case 0xb258: /* bsg */ case 0xb218: /* pc */ case 0xb228: /* pt */ case 0xb98d: /* epsw */ case 0xe560: /* tbegin */ case 0xe561: /* tbeginc */ case 0xb2f8: /* tend */ return -EINVAL; } return 0; } int probe_get_fixup_type(u16 *insn) { /* default fixup method */ int fixup = FIXUP_PSW_NORMAL; switch (insn[0] >> 8) { case 0x05: /* balr */ case 0x0d: /* basr */ fixup = FIXUP_RETURN_REGISTER; /* if r2 = 0, no branch will be taken */ if ((insn[0] & 0x0f) == 0) fixup |= FIXUP_BRANCH_NOT_TAKEN; break; case 0x06: /* bctr */ case 0x07: /* bcr */ fixup = FIXUP_BRANCH_NOT_TAKEN; break; case 0x45: /* bal */ case 0x4d: /* bas */ fixup = FIXUP_RETURN_REGISTER; break; case 0x47: /* bc */ case 0x46: /* bct */ case 0x86: /* bxh */ case 0x87: /* bxle */ fixup = FIXUP_BRANCH_NOT_TAKEN; break; case 0x82: /* lpsw */ fixup = FIXUP_NOT_REQUIRED; break; case 0xb2: /* lpswe */ if ((insn[0] & 0xff) == 0xb2) fixup = FIXUP_NOT_REQUIRED; break; case 0xa7: /* bras */ if ((insn[0] & 0x0f) == 0x05) fixup |= FIXUP_RETURN_REGISTER; break; case 0xc0: if ((insn[0] & 0x0f) == 0x05) /* brasl */ fixup |= FIXUP_RETURN_REGISTER; break; case 0xeb: switch (insn[2] & 0xff) { case 0x44: /* bxhg */ case 0x45: /* bxleg */ fixup = FIXUP_BRANCH_NOT_TAKEN; break; } break; case 0xe3: /* bctg */ if ((insn[2] & 0xff) == 0x46) fixup = FIXUP_BRANCH_NOT_TAKEN; break; case 0xec: switch (insn[2] & 0xff) { case 0xe5: /* clgrb */ case 0xe6: /* cgrb */ case 0xf6: /* crb */ case 0xf7: /* clrb */ case 0xfc: /* cgib */ case 0xfd: /* cglib */ case 0xfe: /* cib */ case 0xff: /* clib */ fixup = FIXUP_BRANCH_NOT_TAKEN; break; } break; } return fixup; } int probe_is_insn_relative_long(u16 *insn) { /* Check if we have a RIL-b or RIL-c format instruction which * we need to modify in order to avoid instruction emulation. */ switch (insn[0] >> 8) { case 0xc0: if ((insn[0] & 0x0f) == 0x00) /* larl */ return true; break; case 0xc4: switch (insn[0] & 0x0f) { case 0x02: /* llhrl */ case 0x04: /* lghrl */ case 0x05: /* lhrl */ case 0x06: /* llghrl */ case 0x07: /* sthrl */ case 0x08: /* lgrl */ case 0x0b: /* stgrl */ case 0x0c: /* lgfrl */ case 0x0d: /* lrl */ case 0x0e: /* llgfrl */ case 0x0f: /* strl */ return true; } break; case 0xc6: switch (insn[0] & 0x0f) { case 0x02: /* pfdrl */ case 0x04: /* cghrl */ case 0x05: /* chrl */ case 0x06: /* clghrl */ case 0x07: /* clhrl */ case 0x08: /* cgrl */ case 0x0a: /* clgrl */ case 0x0c: /* cgfrl */ case 0x0d: /* crl */ case 0x0e: /* clgfrl */ case 0x0f: /* clrl */ return true; } break; } return false; } |