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Diffstat (limited to 'cddl/contrib/opensolaris/lib/libdtrace/i386/dt_isadep.c')
-rw-r--r--cddl/contrib/opensolaris/lib/libdtrace/i386/dt_isadep.c520
1 files changed, 520 insertions, 0 deletions
diff --git a/cddl/contrib/opensolaris/lib/libdtrace/i386/dt_isadep.c b/cddl/contrib/opensolaris/lib/libdtrace/i386/dt_isadep.c
new file mode 100644
index 000000000000..5d8d034fe216
--- /dev/null
+++ b/cddl/contrib/opensolaris/lib/libdtrace/i386/dt_isadep.c
@@ -0,0 +1,520 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
+ * Use is subject to license terms.
+ */
+
+/*
+ * Copyright (c) 2012 by Delphix. All rights reserved.
+ */
+
+#include <stdlib.h>
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+#include <libgen.h>
+
+#include <dt_impl.h>
+#include <dt_pid.h>
+
+#include <dis_tables.h>
+
+#ifdef __FreeBSD__
+#include <libproc.h>
+#include <libproc_compat.h>
+#endif
+
+#define DT_POPL_EBP 0x5d
+#define DT_RET 0xc3
+#define DT_RET16 0xc2
+#define DT_LEAVE 0xc9
+#define DT_JMP32 0xe9
+#define DT_JMP8 0xeb
+#define DT_REP 0xf3
+
+#define DT_MOVL_EBP_ESP 0xe58b
+
+#define DT_ISJ32(op16) (((op16) & 0xfff0) == 0x0f80)
+#define DT_ISJ8(op8) (((op8) & 0xf0) == 0x70)
+
+#define DT_MODRM_REG(modrm) (((modrm) >> 3) & 0x7)
+
+static int dt_instr_size(uchar_t *, dtrace_hdl_t *, pid_t, uintptr_t, char);
+
+/*ARGSUSED*/
+int
+dt_pid_create_entry_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
+ fasttrap_probe_spec_t *ftp, const GElf_Sym *symp)
+{
+ ftp->ftps_type = DTFTP_ENTRY;
+ ftp->ftps_pc = (uintptr_t)symp->st_value;
+ ftp->ftps_size = (size_t)symp->st_size;
+ ftp->ftps_noffs = 1;
+ ftp->ftps_offs[0] = 0;
+
+ if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
+ dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
+ strerror(errno));
+ return (dt_set_errno(dtp, errno));
+ }
+
+ return (1);
+}
+
+static int
+dt_pid_has_jump_table(struct ps_prochandle *P, dtrace_hdl_t *dtp,
+ uint8_t *text, fasttrap_probe_spec_t *ftp, const GElf_Sym *symp)
+{
+ ulong_t i;
+ int size;
+#ifdef illumos
+ pid_t pid = Pstatus(P)->pr_pid;
+ char dmodel = Pstatus(P)->pr_dmodel;
+#else
+ pid_t pid = proc_getpid(P);
+ char dmodel = proc_getmodel(P);
+#endif
+
+ /*
+ * Take a pass through the function looking for a register-dependant
+ * jmp instruction. This could be a jump table so we have to be
+ * ultra conservative.
+ */
+ for (i = 0; i < ftp->ftps_size; i += size) {
+ size = dt_instr_size(&text[i], dtp, pid, symp->st_value + i,
+ dmodel);
+
+ /*
+ * Assume the worst if we hit an illegal instruction.
+ */
+ if (size <= 0) {
+ dt_dprintf("error at %#lx (assuming jump table)\n", i);
+ return (1);
+ }
+
+#ifdef notyet
+ /*
+ * Register-dependant jmp instructions start with a 0xff byte
+ * and have the modrm.reg field set to 4. They can have an
+ * optional REX prefix on the 64-bit ISA.
+ */
+ if ((text[i] == 0xff && DT_MODRM_REG(text[i + 1]) == 4) ||
+ (dmodel == PR_MODEL_LP64 && (text[i] & 0xf0) == 0x40 &&
+ text[i + 1] == 0xff && DT_MODRM_REG(text[i + 2]) == 4)) {
+ dt_dprintf("found a suspected jump table at %s:%lx\n",
+ ftp->ftps_func, i);
+ return (1);
+ }
+#endif
+ }
+
+ return (0);
+}
+
+/*ARGSUSED*/
+int
+dt_pid_create_return_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
+ fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, uint64_t *stret)
+{
+ uint8_t *text;
+ ulong_t i, end;
+ int size;
+#ifdef illumos
+ pid_t pid = Pstatus(P)->pr_pid;
+ char dmodel = Pstatus(P)->pr_dmodel;
+#else
+ pid_t pid = proc_getpid(P);
+ char dmodel = proc_getmodel(P);
+#endif
+
+ /*
+ * We allocate a few extra bytes at the end so we don't have to check
+ * for overrunning the buffer.
+ */
+ if ((text = calloc(1, symp->st_size + 4)) == NULL) {
+ dt_dprintf("mr sparkle: malloc() failed\n");
+ return (DT_PROC_ERR);
+ }
+
+ if (Pread(P, text, symp->st_size, symp->st_value) != symp->st_size) {
+ dt_dprintf("mr sparkle: Pread() failed\n");
+ free(text);
+ return (DT_PROC_ERR);
+ }
+
+ ftp->ftps_type = DTFTP_RETURN;
+ ftp->ftps_pc = (uintptr_t)symp->st_value;
+ ftp->ftps_size = (size_t)symp->st_size;
+ ftp->ftps_noffs = 0;
+
+ /*
+ * If there's a jump table in the function we're only willing to
+ * instrument these specific (and equivalent) instruction sequences:
+ * leave
+ * [rep] ret
+ * and
+ * movl %ebp,%esp
+ * popl %ebp
+ * [rep] ret
+ *
+ * We do this to avoid accidentally interpreting jump table
+ * offsets as actual instructions.
+ */
+ if (dt_pid_has_jump_table(P, dtp, text, ftp, symp)) {
+ for (i = 0, end = ftp->ftps_size; i < end; i += size) {
+ size = dt_instr_size(&text[i], dtp, pid,
+ symp->st_value + i, dmodel);
+
+ /* bail if we hit an invalid opcode */
+ if (size <= 0)
+ break;
+
+ if (text[i] == DT_LEAVE && text[i + 1] == DT_RET) {
+ dt_dprintf("leave/ret at %lx\n", i + 1);
+ ftp->ftps_offs[ftp->ftps_noffs++] = i + 1;
+ size = 2;
+ } else if (text[i] == DT_LEAVE &&
+ text[i + 1] == DT_REP && text[i + 2] == DT_RET) {
+ dt_dprintf("leave/rep ret at %lx\n", i + 1);
+ ftp->ftps_offs[ftp->ftps_noffs++] = i + 1;
+ size = 3;
+ } else if (*(uint16_t *)&text[i] == DT_MOVL_EBP_ESP &&
+ text[i + 2] == DT_POPL_EBP &&
+ text[i + 3] == DT_RET) {
+ dt_dprintf("movl/popl/ret at %lx\n", i + 3);
+ ftp->ftps_offs[ftp->ftps_noffs++] = i + 3;
+ size = 4;
+ } else if (*(uint16_t *)&text[i] == DT_MOVL_EBP_ESP &&
+ text[i + 2] == DT_POPL_EBP &&
+ text[i + 3] == DT_REP &&
+ text[i + 4] == DT_RET) {
+ dt_dprintf("movl/popl/rep ret at %lx\n", i + 3);
+ ftp->ftps_offs[ftp->ftps_noffs++] = i + 3;
+ size = 5;
+ }
+ }
+ } else {
+ for (i = 0, end = ftp->ftps_size; i < end; i += size) {
+ size = dt_instr_size(&text[i], dtp, pid,
+ symp->st_value + i, dmodel);
+
+ /* bail if we hit an invalid opcode */
+ if (size <= 0)
+ break;
+
+ /* ordinary ret */
+ if (size == 1 && text[i] == DT_RET)
+ goto is_ret;
+
+ /* two-byte ret */
+ if (size == 2 && text[i] == DT_REP &&
+ text[i + 1] == DT_RET)
+ goto is_ret;
+
+ /* ret <imm16> */
+ if (size == 3 && text[i] == DT_RET16)
+ goto is_ret;
+
+ /* two-byte ret <imm16> */
+ if (size == 4 && text[i] == DT_REP &&
+ text[i + 1] == DT_RET16)
+ goto is_ret;
+
+ /* 32-bit displacement jmp outside of the function */
+ if (size == 5 && text[i] == DT_JMP32 && symp->st_size <=
+ (uintptr_t)(i + size + *(int32_t *)&text[i + 1]))
+ goto is_ret;
+
+ /* 8-bit displacement jmp outside of the function */
+ if (size == 2 && text[i] == DT_JMP8 && symp->st_size <=
+ (uintptr_t)(i + size + *(int8_t *)&text[i + 1]))
+ goto is_ret;
+
+ /* 32-bit disp. conditional jmp outside of the func. */
+ if (size == 6 && DT_ISJ32(*(uint16_t *)&text[i]) &&
+ symp->st_size <=
+ (uintptr_t)(i + size + *(int32_t *)&text[i + 2]))
+ goto is_ret;
+
+ /* 8-bit disp. conditional jmp outside of the func. */
+ if (size == 2 && DT_ISJ8(text[i]) && symp->st_size <=
+ (uintptr_t)(i + size + *(int8_t *)&text[i + 1]))
+ goto is_ret;
+
+ continue;
+is_ret:
+ dt_dprintf("return at offset %lx\n", i);
+ ftp->ftps_offs[ftp->ftps_noffs++] = i;
+ }
+ }
+
+ free(text);
+ if (ftp->ftps_noffs > 0) {
+ if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
+ dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
+ strerror(errno));
+ return (dt_set_errno(dtp, errno));
+ }
+ }
+
+ return (ftp->ftps_noffs);
+}
+
+/*ARGSUSED*/
+int
+dt_pid_create_offset_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
+ fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, ulong_t off)
+{
+ ftp->ftps_type = DTFTP_OFFSETS;
+ ftp->ftps_pc = (uintptr_t)symp->st_value;
+ ftp->ftps_size = (size_t)symp->st_size;
+ ftp->ftps_noffs = 1;
+
+ if (strcmp("-", ftp->ftps_func) == 0) {
+ ftp->ftps_offs[0] = off;
+ } else {
+ uint8_t *text;
+ ulong_t i;
+ int size;
+#ifdef illumos
+ pid_t pid = Pstatus(P)->pr_pid;
+ char dmodel = Pstatus(P)->pr_dmodel;
+#else
+ pid_t pid = proc_getpid(P);
+ char dmodel = proc_getmodel(P);
+#endif
+
+ if ((text = malloc(symp->st_size)) == NULL) {
+ dt_dprintf("mr sparkle: malloc() failed\n");
+ return (DT_PROC_ERR);
+ }
+
+ if (Pread(P, text, symp->st_size, symp->st_value) !=
+ symp->st_size) {
+ dt_dprintf("mr sparkle: Pread() failed\n");
+ free(text);
+ return (DT_PROC_ERR);
+ }
+
+ /*
+ * We can't instrument offsets in functions with jump tables
+ * as we might interpret a jump table offset as an
+ * instruction.
+ */
+ if (dt_pid_has_jump_table(P, dtp, text, ftp, symp)) {
+ free(text);
+ return (0);
+ }
+
+ for (i = 0; i < symp->st_size; i += size) {
+ if (i == off) {
+ ftp->ftps_offs[0] = i;
+ break;
+ }
+
+ /*
+ * If we've passed the desired offset without a
+ * match, then the given offset must not lie on a
+ * instruction boundary.
+ */
+ if (i > off) {
+ free(text);
+ return (DT_PROC_ALIGN);
+ }
+
+ size = dt_instr_size(&text[i], dtp, pid,
+ symp->st_value + i, dmodel);
+
+ /*
+ * If we hit an invalid instruction, bail as if we
+ * couldn't find the offset.
+ */
+ if (size <= 0) {
+ free(text);
+ return (DT_PROC_ALIGN);
+ }
+ }
+
+ free(text);
+ }
+
+ if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
+ dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
+ strerror(errno));
+ return (dt_set_errno(dtp, errno));
+ }
+
+ return (ftp->ftps_noffs);
+}
+
+/*ARGSUSED*/
+int
+dt_pid_create_glob_offset_probes(struct ps_prochandle *P, dtrace_hdl_t *dtp,
+ fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, const char *pattern)
+{
+ uint8_t *text;
+ int size;
+ ulong_t i, end = symp->st_size;
+#ifdef illumos
+ pid_t pid = Pstatus(P)->pr_pid;
+ char dmodel = Pstatus(P)->pr_dmodel;
+#else
+ pid_t pid = proc_getpid(P);
+ char dmodel = proc_getmodel(P);
+#endif
+
+ ftp->ftps_type = DTFTP_OFFSETS;
+ ftp->ftps_pc = (uintptr_t)symp->st_value;
+ ftp->ftps_size = (size_t)symp->st_size;
+ ftp->ftps_noffs = 0;
+
+ if ((text = malloc(symp->st_size)) == NULL) {
+ dt_dprintf("mr sparkle: malloc() failed\n");
+ return (DT_PROC_ERR);
+ }
+
+ if (Pread(P, text, symp->st_size, symp->st_value) != symp->st_size) {
+ dt_dprintf("mr sparkle: Pread() failed\n");
+ free(text);
+ return (DT_PROC_ERR);
+ }
+
+ /*
+ * We can't instrument offsets in functions with jump tables as
+ * we might interpret a jump table offset as an instruction.
+ */
+ if (dt_pid_has_jump_table(P, dtp, text, ftp, symp)) {
+ free(text);
+ return (0);
+ }
+
+ if (strcmp("*", pattern) == 0) {
+ for (i = 0; i < end; i += size) {
+ ftp->ftps_offs[ftp->ftps_noffs++] = i;
+
+ size = dt_instr_size(&text[i], dtp, pid,
+ symp->st_value + i, dmodel);
+
+ /* bail if we hit an invalid opcode */
+ if (size <= 0)
+ break;
+ }
+ } else {
+ char name[sizeof (i) * 2 + 1];
+
+ for (i = 0; i < end; i += size) {
+ (void) snprintf(name, sizeof (name), "%lx", i);
+ if (gmatch(name, pattern))
+ ftp->ftps_offs[ftp->ftps_noffs++] = i;
+
+ size = dt_instr_size(&text[i], dtp, pid,
+ symp->st_value + i, dmodel);
+
+ /* bail if we hit an invalid opcode */
+ if (size <= 0)
+ break;
+ }
+ }
+
+ free(text);
+ if (ftp->ftps_noffs > 0) {
+ if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
+ dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
+ strerror(errno));
+ return (dt_set_errno(dtp, errno));
+ }
+ }
+
+ return (ftp->ftps_noffs);
+}
+
+typedef struct dtrace_dis {
+ uchar_t *instr;
+ dtrace_hdl_t *dtp;
+ pid_t pid;
+ uintptr_t addr;
+} dtrace_dis_t;
+
+static int
+dt_getbyte(void *data)
+{
+ dtrace_dis_t *dis = data;
+ int ret = *dis->instr;
+
+ if (ret == FASTTRAP_INSTR) {
+ fasttrap_instr_query_t instr;
+
+ instr.ftiq_pid = dis->pid;
+ instr.ftiq_pc = dis->addr;
+
+ /*
+ * If we hit a byte that looks like the fasttrap provider's
+ * trap instruction (which doubles as the breakpoint
+ * instruction for debuggers) we need to query the kernel
+ * for the real value. This may just be part of an immediate
+ * value so there's no need to return an error if the
+ * kernel doesn't know about this address.
+ */
+ if (ioctl(dis->dtp->dt_ftfd, FASTTRAPIOC_GETINSTR, &instr) == 0)
+ ret = instr.ftiq_instr;
+ }
+
+ dis->addr++;
+ dis->instr++;
+
+ return (ret);
+}
+
+static int
+dt_instr_size(uchar_t *instr, dtrace_hdl_t *dtp, pid_t pid, uintptr_t addr,
+ char dmodel)
+{
+ dtrace_dis_t data;
+ dis86_t x86dis;
+ uint_t cpu_mode;
+
+ data.instr = instr;
+ data.dtp = dtp;
+ data.pid = pid;
+ data.addr = addr;
+
+ x86dis.d86_data = &data;
+ x86dis.d86_get_byte = dt_getbyte;
+ x86dis.d86_check_func = NULL;
+
+ cpu_mode = (dmodel == PR_MODEL_ILP32) ? SIZE32 : SIZE64;
+
+ if (dtrace_disx86(&x86dis, cpu_mode) != 0)
+ return (-1);
+
+ /*
+ * If the instruction was a single-byte breakpoint, there may be
+ * another debugger attached to this process. The original instruction
+ * can't be recovered so this must fail.
+ */
+ if (x86dis.d86_len == 1 &&
+ (uchar_t)x86dis.d86_bytes[0] == FASTTRAP_INSTR)
+ return (-1);
+
+ return (x86dis.d86_len);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-18 12:01:29 +0000