svn commit: r307964 - head/lib/libproc

[Ruslan Bukin]

Author: br
Date: Wed Oct 26 14:26:45 2016
New Revision: 307964
URL: https://svnweb.freebsd.org/changeset/base/307964

Log:
  Use uint32_t instead of u_long as a storage for breakpoint instruction
  to copy. All the platforms breakpoints fits this fine.
  
  This fixes operation on big-endian MIPS64 where we were coping
  zeroes instead of real instruction.
  
  Reviewed by:	rpaulo
  Sponsored by:	DARPA, AFRL
  Sponsored by:	HEIF5
  Differential Revision:	https://reviews.freebsd.org/D8250

Modified:
  head/lib/libproc/proc_bkpt.c

Modified: head/lib/libproc/proc_bkpt.c
==============================================================================
--- head/lib/libproc/proc_bkpt.c	Wed Oct 26 14:09:30 2016	(r307963)
+++ head/lib/libproc/proc_bkpt.c	Wed Oct 26 14:26:45 2016	(r307964)
@@ -68,6 +68,14 @@ __FBSDID("$FreeBSD$");
 #error "Add support for your architecture"
 #endif
 
+/*
+ * Use 4-bytes holder for breakpoint instruction on all the platforms.
+ * Works for x86 as well until it is endian-little platform.
+ * (We are coping one byte only on x86 from this 4-bytes piece of
+ * memory).
+ */
+typedef uint32_t instr_t;
+
 static int
 proc_stop(struct proc_handle *phdl)
 {
@@ -92,8 +100,9 @@ proc_bkptset(struct proc_handle *phdl, u
     unsigned long *saved)
 {
 	struct ptrace_io_desc piod;
-	unsigned long paddr, caddr;
+	unsigned long caddr;
 	int ret = 0, stopped;
+	instr_t instr;
 
 	*saved = 0;
 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
@@ -115,10 +124,10 @@ proc_bkptset(struct proc_handle *phdl, u
 	 * Read the original instruction.
 	 */
 	caddr = address;
-	paddr = 0;
+	instr = 0;
 	piod.piod_op = PIOD_READ_I;
 	piod.piod_offs = (void *)caddr;
-	piod.piod_addr = &paddr;
+	piod.piod_addr = &instr;
 	piod.piod_len  = BREAKPOINT_INSTR_SZ;
 	if (ptrace(PT_IO, proc_getpid(phdl), (caddr_t)&piod, 0) < 0) {
 		DPRINTF("ERROR: couldn't read instruction at address 0x%"
@@ -126,15 +135,15 @@ proc_bkptset(struct proc_handle *phdl, u
 		ret = -1;
 		goto done;
 	}
-	*saved = paddr;
+	*saved = instr;
 	/*
 	 * Write a breakpoint instruction to that address.
 	 */
 	caddr = address;
-	paddr = BREAKPOINT_INSTR;
+	instr = BREAKPOINT_INSTR;
 	piod.piod_op = PIOD_WRITE_I;
 	piod.piod_offs = (void *)caddr;
-	piod.piod_addr = &paddr;
+	piod.piod_addr = &instr;
 	piod.piod_len  = BREAKPOINT_INSTR_SZ;
 	if (ptrace(PT_IO, proc_getpid(phdl), (caddr_t)&piod, 0) < 0) {
 		DPRINTF("ERROR: couldn't write instruction at address 0x%"
@@ -156,8 +165,9 @@ proc_bkptdel(struct proc_handle *phdl, u
     unsigned long saved)
 {
 	struct ptrace_io_desc piod;
-	unsigned long paddr, caddr;
+	unsigned long caddr;
 	int ret = 0, stopped;
+	instr_t instr;
 
 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
 	    phdl->status == PS_IDLE) {
@@ -178,10 +188,10 @@ proc_bkptdel(struct proc_handle *phdl, u
 	 * Overwrite the breakpoint instruction that we setup previously.
 	 */
 	caddr = address;
-	paddr = saved;
+	instr = saved;
 	piod.piod_op = PIOD_WRITE_I;
 	piod.piod_offs = (void *)caddr;
-	piod.piod_addr = &paddr;
+	piod.piod_addr = &instr;
 	piod.piod_len  = BREAKPOINT_INSTR_SZ;
 	if (ptrace(PT_IO, proc_getpid(phdl), (caddr_t)&piod, 0) < 0) {
 		DPRINTF("ERROR: couldn't write instruction at address 0x%"