[COMMITTED] readelf: Robustify print_cfa_program.

[COMMITTED] readelf: Robustify print_cfa_program.

[Mark Wielaard]

[-- Attachment #1: Type: text/plain, Size: 2104 bytes --]

Check block len before calling print_ops.

Signed-off-by: Mark Wielaard <mjw@redhat.com>
---
 src/ChangeLog |  5 +++++
 src/readelf.c | 10 ++++++++++
 2 files changed, 15 insertions(+)

diff --git a/src/ChangeLog b/src/ChangeLog
index 7561041..fefd6c1 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2014-11-16  Mark Wielaard  <mjw@redhat.com>
+
+	* readelf.c (print_cfa_program): Check block len before calling
+	print_ops.
+
 2014-11-14  Mark Wielaard  <mjw@redhat.com>
 
 	* readelf.c (print_debug_frame_section): Sanity Check CIE
diff --git a/src/readelf.c b/src/readelf.c
index 065ee1c..697a0e5 100644
--- a/src/readelf.c
+++ b/src/readelf.c
@@ -4980,6 +4980,12 @@ print_cfa_program (const unsigned char *readp, const unsigned char *const endp,
 	    // XXX overflow check
 	    get_uleb128 (op1, readp);	/* Length of DW_FORM_block.  */
 	    printf ("     def_cfa_expression %" PRIu64 "\n", op1);
+	    if ((uint64_t) (endp - readp) < op1)
+	      {
+	    invalid:
+	        fputs (gettext ("         <INVALID DATA>\n"), stdout);
+		return;
+	      }
 	    print_ops (dwflmod, dbg, 10, 10, version, ptr_size, 0, NULL,
 		       op1, readp);
 	    readp += op1;
@@ -4990,6 +4996,8 @@ print_cfa_program (const unsigned char *readp, const unsigned char *const endp,
 	    get_uleb128 (op2, readp);	/* Length of DW_FORM_block.  */
 	    printf ("     expression r%" PRIu64 " (%s) \n",
 		    op1, regname (op1));
+	    if ((uint64_t) (endp - readp) < op1)
+	      goto invalid;
 	    print_ops (dwflmod, dbg, 10, 10, version, ptr_size, 0, NULL,
 		       op2, readp);
 	    readp += op2;
@@ -5034,6 +5042,8 @@ print_cfa_program (const unsigned char *readp, const unsigned char *const endp,
 	    get_uleb128 (op2, readp);	/* Length of DW_FORM_block.  */
 	    printf ("     val_expression r%" PRIu64 " (%s)\n",
 		    op1, regname (op1));
+	    if ((uint64_t) (endp - readp) < op2)
+	      goto invalid;
 	    print_ops (dwflmod, dbg, 10, 10, version, ptr_size, 0,
 		       NULL, op2, readp);
 	    readp += op2;
-- 
1.8.3.1