dwarf-reader: handle binaries with missing symtab

Message ID 20200127073846.107009-1-maennich@google.com
State Committed
Headers
Series dwarf-reader: handle binaries with missing symtab |

Commit Message

Aleksei Vetrov via Libabigail Jan. 1, 2020, midnight UTC
  A broken elf file might not have a valid symtab. As of now we would hit
an ABG_ASSERT and crash. Let's catch that case and bail out instead.

        * src/abg-dwarf-reader.cc (load_symbol_maps_from_symtab_section):
        Handle elf file with missing symtab.
        * tests/test-read-dwarf.cc (InOutSpec): add test case.
        * tests/data/test-read-dwarf/test26-bogus-binary.elf: new test data.

Signed-off-by: Matthias Maennich <maennich@google.com>
---
 src/abg-dwarf-reader.cc                           |   3 ++-
 .../data/test-read-dwarf/test26-bogus-binary.elf  | Bin 0 -> 200 bytes
 tests/test-read-dwarf.cc                          |   6 ++++++
 3 files changed, 8 insertions(+), 1 deletion(-)
 create mode 100644 tests/data/test-read-dwarf/test26-bogus-binary.elf
  

Comments

Dodji Seketeli Jan. 1, 2020, midnight UTC | #1
Hello Matthias,

Matthias Maennich <maennich@google.com> a ?crit:

> A broken elf file might not have a valid symtab. As of now we would hit
> an ABG_ASSERT and crash. Let's catch that case and bail out instead.
>
>         * src/abg-dwarf-reader.cc (load_symbol_maps_from_symtab_section):
>         Handle elf file with missing symtab.
>         * tests/test-read-dwarf.cc (InOutSpec): add test case.
>         * tests/data/test-read-dwarf/test26-bogus-binary.elf: new test data.

This is OK to commit to master.

Thanks!
  
Aleksei Vetrov via Libabigail Jan. 1, 2020, midnight UTC | #2
On Mon, Jan 27, 2020 at 04:21:21PM +0100, Dodji Seketeli wrote:
>Hello Matthias,
>
>Matthias Maennich <maennich@google.com> a ?crit:
>
>> A broken elf file might not have a valid symtab. As of now we would hit
>> an ABG_ASSERT and crash. Let's catch that case and bail out instead.
>>
>>         * src/abg-dwarf-reader.cc (load_symbol_maps_from_symtab_section):
>>         Handle elf file with missing symtab.
>>         * tests/test-read-dwarf.cc (InOutSpec): add test case.
>>         * tests/data/test-read-dwarf/test26-bogus-binary.elf: new test data.
>
>This is OK to commit to master.

Done. Thanks!

Cheers,
Matthias

>
>Thanks!
>
>-- 
>		Dodji
  

Patch

diff --git a/src/abg-dwarf-reader.cc b/src/abg-dwarf-reader.cc
index 555170eccdf0..f6ab72c7dabb 100644
--- a/src/abg-dwarf-reader.cc
+++ b/src/abg-dwarf-reader.cc
@@ -7396,7 +7396,8 @@  public:
     size_t nb_syms = symtab_sheader->sh_size / symtab_sheader->sh_entsize;
 
     Elf_Data* symtab = elf_getdata(symtab_section, 0);
-    ABG_ASSERT(symtab);
+    if (!symtab)
+      return false;
 
     GElf_Ehdr elf_header;
     ABG_ASSERT(gelf_getehdr(elf_handle(), &elf_header));
diff --git a/tests/data/test-read-dwarf/test26-bogus-binary.elf b/tests/data/test-read-dwarf/test26-bogus-binary.elf
new file mode 100644
index 0000000000000000000000000000000000000000..e16c0b84907c315362bdf8a887468bb0dae0aaf8
GIT binary patch
literal 200
zcmb<-^>JflWMpArWB>vXLl?wgVBmmIU~+W{8xV-GvGMV-0tNp6XW(I|0|EvyAg>OH
z|NV!8d{-C?L^J>Y9}YGEqz4M1e1;u$4BS9AP!wn@gz*a`2NVZ#L5dj||Ns9Dq;LVS
NlEggSq|7`9I{+HKKxzO0

literal 0
HcmV?d00001

diff --git a/tests/test-read-dwarf.cc b/tests/test-read-dwarf.cc
index 8f460fef3f8f..c33c77290850 100644
--- a/tests/test-read-dwarf.cc
+++ b/tests/test-read-dwarf.cc
@@ -259,6 +259,12 @@  InOutSpec in_out_specs[] =
     "",
     "",
   },
+  {
+    "data/test-read-dwarf/test26-bogus-binary.elf",
+    "",
+    "",
+    "",
+  },
   // This should be the last entry.
   {NULL, NULL, NULL, NULL}
 };