[PATCH] src: fix DEREF_OF_NULL.RET.STAT in readelf.c in

[Anton Moryakov]

Static analyzer reported:
Return value of a function 'elf_strptr' is dereferenced at readelf.c:7171
without checking for NULL, but it is usually checked for this function (71/74).

Corrections explained:
- Added a NULL check for the scnname variable, which contains the result of
  the elf_strptr call.
- The check is placed before the first use of scnname to prevent dereferencing
  a NULL pointer.

Triggers found by static analyzer Svace.

Signed-off-by: Anton Moryakov <ant.v.moryakov@gmail.com>
---
 src/readelf.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/readelf.c b/src/readelf.c
index 6526db07..86ab3d37 100644
--- a/src/readelf.c
+++ b/src/readelf.c
@@ -7168,6 +7168,11 @@ print_debug_frame_section (Dwfl_Module *dwflmod, Ebl *ebl, GElf_Ehdr *ehdr,
       return;
     }
 
+  if (scnname == NULL)
+    {
+      error (0, 0, _("cannot get section name: %s"), elf_errmsg (-1));
+      return;
+    }
   bool is_eh_frame = strcmp (scnname, ".eh_frame") == 0;
   Elf_Data *data;
   if (is_eh_frame)
-- 
2.30.2