[COMMITTED] libdwfl: dwfl_module_getdwarf.c don't use symtab with bogus sh_entsize.

[COMMITTED] libdwfl: dwfl_module_getdwarf.c don't use symtab with bogus sh_entsize.

[Mark Wielaard]

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Those will cause a divide by zero. We have no way to know what size the
entries are.

Signed-off-by: Mark Wielaard <mjw@redhat.com>
---
 libdwfl/ChangeLog              | 5 +++++
 libdwfl/dwfl_module_getdwarf.c | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/libdwfl/ChangeLog b/libdwfl/ChangeLog
index 78314c4..22bc783 100644
--- a/libdwfl/ChangeLog
+++ b/libdwfl/ChangeLog
@@ -1,3 +1,8 @@
+2014-11-14  Mark Wielaard  <mjw@redhat.com>
+
+	* dwfl_module_getdwarf.c (load_symtab): Don't use tables which have
+	a zero sh_entsize.
+
 2014-11-10  Mark Wielaard  <mjw@redhat.com>
 
 	* dwfl_module_getdwarf.c (find_dynsym): New inner function
diff --git a/libdwfl/dwfl_module_getdwarf.c b/libdwfl/dwfl_module_getdwarf.c
index adb94b4..a20875b 100644
--- a/libdwfl/dwfl_module_getdwarf.c
+++ b/libdwfl/dwfl_module_getdwarf.c
@@ -575,6 +575,8 @@ load_symtab (struct dwfl_file *file, struct dwfl_file **symfile,
 	switch (shdr->sh_type)
 	  {
 	  case SHT_SYMTAB:
+	    if (shdr->sh_entsize == 0)
+	      break;
 	    symtab = true;
 	    *symscn = scn;
 	    *symfile = file;
@@ -589,6 +591,8 @@ load_symtab (struct dwfl_file *file, struct dwfl_file **symfile,
 	    if (symtab)
 	      break;
 	    /* Use this if need be, but keep looking for SHT_SYMTAB.  */
+	    if (shdr->sh_entsize == 0)
+	      break;
 	    *symscn = scn;
 	    *symfile = file;
 	    *strshndx = shdr->sh_link;
-- 
1.8.3.1