[binutils-gdb] gdb/linux-record: Fix old_select syscall handling

[Pedro Alves <palves at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=ff83a547feacaea9263c04f527aba4faae77035f

commit ff83a547feacaea9263c04f527aba4faae77035f
Author: Marcin KoÅ?cielnicki <koriakin@0x04.net>
Date:   Fri Oct 30 15:52:01 2015 +0000

    gdb/linux-record: Fix old_select syscall handling
    
    We have to use extract_unsigned_integer to read paramaters structure - target
    pointers can have different endianness and size.
    
    gdb/ChangeLog:
    
    	* linux-record.c (record_linux_system_call): Fix old_select.

Diff:
---
 gdb/ChangeLog      |  4 ++++
 gdb/linux-record.c | 45 ++++++++++++++++++++++++++-------------------
 2 files changed, 30 insertions(+), 19 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 433ec95..509fd7e 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,9 @@
 2015-10-30  Marcin KoÅ?cielnicki  <koriakin@0x04.net>
 
+	* linux-record.c (record_linux_system_call): Fix old_select.
+
+2015-10-30  Marcin KoÅ?cielnicki  <koriakin@0x04.net>
+
 	* linux-record.c (record_linux_system_call): Fix newstatat.
 
 2015-10-30  Marcin KoÅ?cielnicki  <koriakin@0x04.net>
diff --git a/gdb/linux-record.c b/gdb/linux-record.c
index 9f38c0b..091ac8a 100644
--- a/gdb/linux-record.c
+++ b/gdb/linux-record.c
@@ -645,38 +645,45 @@ record_linux_system_call (enum gdb_syscall syscall,
 
     case gdb_old_select:
       {
-        struct sel_arg_struct
-        {
-          CORE_ADDR n;
-          CORE_ADDR inp;
-          CORE_ADDR outp;
-          CORE_ADDR exp;
-          CORE_ADDR tvp;
-        } sel;
+        unsigned long sz_sel_arg = tdep->size_long + tdep->size_pointer * 4;
+        gdb_byte *a = (gdb_byte *) alloca (sz_sel_arg);
+        CORE_ADDR inp, outp, exp, tvp;
 
         regcache_raw_read_unsigned (regcache, tdep->arg1,
                                     &tmpulongest);
         if (tmpulongest)
           {
-            if (target_read_memory (tmpulongest, (gdb_byte *) &sel,
-                                    sizeof(sel)))
+            if (target_read_memory (tmpulongest, a, sz_sel_arg))
               {
                 if (record_debug)
                   fprintf_unfiltered (gdb_stdlog,
                                       "Process record: error reading memory "
                                       "at addr = 0x%s len = %lu.\n",
                                       OUTPUT_REG (tmpulongest, tdep->arg1),
-                                      (unsigned long) sizeof (sel));
+                                      sz_sel_arg);
                 return -1;
               }
-            if (record_full_arch_list_add_mem (sel.inp, tdep->size_fd_set))
-              return -1;
-            if (record_full_arch_list_add_mem (sel.outp, tdep->size_fd_set))
-              return -1;
-            if (record_full_arch_list_add_mem (sel.exp, tdep->size_fd_set))
-              return -1;
-            if (record_full_arch_list_add_mem (sel.tvp, tdep->size_timeval))
-              return -1;
+            /* Skip n. */
+            a += tdep->size_long;
+            inp = extract_unsigned_integer (a, tdep->size_pointer, byte_order);
+            a += tdep->size_pointer;
+            outp = extract_unsigned_integer (a, tdep->size_pointer, byte_order);
+            a += tdep->size_pointer;
+            exp = extract_unsigned_integer (a, tdep->size_pointer, byte_order);
+            a += tdep->size_pointer;
+            tvp = extract_unsigned_integer (a, tdep->size_pointer, byte_order);
+            if (inp)
+              if (record_full_arch_list_add_mem (inp, tdep->size_fd_set))
+                return -1;
+            if (outp)
+              if (record_full_arch_list_add_mem (outp, tdep->size_fd_set))
+                return -1;
+            if (exp)
+              if (record_full_arch_list_add_mem (exp, tdep->size_fd_set))
+                return -1;
+            if (tvp)
+              if (record_full_arch_list_add_mem (tvp, tdep->size_timeval))
+                return -1;
           }
       }
       break;