diff mbox series

elf: _dl_find_object may return 1 during early startup (bug 30515)

Message ID 877cshzzmz.fsf@oldenburg.str.redhat.com
State New
Headers show
Series elf: _dl_find_object may return 1 during early startup (bug 30515) | expand

Commit Message

Florian Weimer June 5, 2023, 3:40 p.m. UTC
Success is reported with a 0 return value, and failure is -1.
Enhance the kitchen sink test elf/tst-audit28 to cover
_dl_find_object as well.

Fixes commit 5d28a8962dcb ("elf: Add _dl_find_object function")
and bug 30515.

Tested on x86_64-linux-gnu.

---
 elf/dl-find_object.c | 2 +-
 elf/tst-auditmod28.c | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)


base-commit: 7f0d9e61f40c669fca3cfd1e342fa8236c7220b7

Comments

Adhemerval Zanella Netto June 6, 2023, 7:45 p.m. UTC | #1
On 05/06/23 12:40, Florian Weimer via Libc-alpha wrote:
> Success is reported with a 0 return value, and failure is -1.
> Enhance the kitchen sink test elf/tst-audit28 to cover
> _dl_find_object as well.
> 
> Fixes commit 5d28a8962dcb ("elf: Add _dl_find_object function")
> and bug 30515.
> 
> Tested on x86_64-linux-gnu.
> 
> ---
>  elf/dl-find_object.c | 2 +-
>  elf/tst-auditmod28.c | 9 +++++++++
>  2 files changed, 10 insertions(+), 1 deletion(-)
> 
> diff --git a/elf/dl-find_object.c b/elf/dl-find_object.c
> index 928eb499cc..c1390ee10f 100644
> --- a/elf/dl-find_object.c
> +++ b/elf/dl-find_object.c
> @@ -46,7 +46,7 @@ _dl_find_object_slow (void *pc, struct dl_find_object *result)
>            struct dl_find_object_internal internal;
>            _dl_find_object_from_map (l, &internal);
>            _dl_find_object_to_external (&internal, result);
> -          return 1;
> +          return 0;
>          }
>  
>    /* Object not found.  */

Ok.

> diff --git a/elf/tst-auditmod28.c b/elf/tst-auditmod28.c
> index f6ab991398..ae9c277f5b 100644
> --- a/elf/tst-auditmod28.c
> +++ b/elf/tst-auditmod28.c
> @@ -71,6 +71,15 @@ la_version (unsigned int current)
>    TEST_VERIFY (dladdr1 (&_exit, &info, &extra_info, RTLD_DL_LINKMAP) != 0);
>    TEST_VERIFY (extra_info == handle);
>  
> +  /* Check _dl_find_object.  */
> +  struct dl_find_object dlfo;
> +  TEST_COMPARE (_dl_find_object (__builtin_return_address (0), &dlfo), 0);
> +  TEST_COMPARE_STRING (basename (dlfo.dlfo_link_map->l_name), LD_SO);

Unfortunately this fails with --enable-hardcoded-path-in-tests, since the INTERP
will be set to ld.so:

x86_64-linux-gnu$ readelf -p .interp elf/tst-audit28

String dump of section '.interp':
  [     0]  [...]/x86_64-linux-gnu/elf/ld.so 

x86_64-linux-gnu$ make test t=elf/tst-audit28
[...]
FAIL: elf/tst-audit28
original exit status 1
tst-auditmod28.c:77: error: string comparison failed
  left string: 5 bytes
  right string: 20 bytes
  left (evaluated from basename (dlfo.dlfo_link_map->l_name)):
      "ld.so"
      6C 64 2E 73 6F
  right (evaluated from LD_SO):
      "ld-linux-x86-64.so.2"
      6C 64 2D 6C 69 6E 75 78 2D 78 38 36 2D 36 34 2E 73 6F 2E 32
[...]

Maybe add a check for either ld.so or LD_SO.

> +  TEST_COMPARE (_dl_find_object (dlsym (handle, "environ"), &dlfo), 0);
> +  TEST_COMPARE_STRING (basename (dlfo.dlfo_link_map->l_name), LIBC_SO);
> +  TEST_COMPARE (_dl_find_object ((void *) 1, &dlfo), -1);
> +  TEST_COMPARE (_dl_find_object ((void *) -1, &dlfo), -1);
> +
>    /* Verify that dlmopen creates a new namespace.  */
>    void *dlmopen_handle = xdlmopen (LM_ID_NEWLM, LIBC_SO, RTLD_NOW);
>    TEST_VERIFY (dlmopen_handle != handle);
> 
> base-commit: 7f0d9e61f40c669fca3cfd1e342fa8236c7220b7
>
diff mbox series

Patch

diff --git a/elf/dl-find_object.c b/elf/dl-find_object.c
index 928eb499cc..c1390ee10f 100644
--- a/elf/dl-find_object.c
+++ b/elf/dl-find_object.c
@@ -46,7 +46,7 @@  _dl_find_object_slow (void *pc, struct dl_find_object *result)
           struct dl_find_object_internal internal;
           _dl_find_object_from_map (l, &internal);
           _dl_find_object_to_external (&internal, result);
-          return 1;
+          return 0;
         }
 
   /* Object not found.  */
diff --git a/elf/tst-auditmod28.c b/elf/tst-auditmod28.c
index f6ab991398..ae9c277f5b 100644
--- a/elf/tst-auditmod28.c
+++ b/elf/tst-auditmod28.c
@@ -71,6 +71,15 @@  la_version (unsigned int current)
   TEST_VERIFY (dladdr1 (&_exit, &info, &extra_info, RTLD_DL_LINKMAP) != 0);
   TEST_VERIFY (extra_info == handle);
 
+  /* Check _dl_find_object.  */
+  struct dl_find_object dlfo;
+  TEST_COMPARE (_dl_find_object (__builtin_return_address (0), &dlfo), 0);
+  TEST_COMPARE_STRING (basename (dlfo.dlfo_link_map->l_name), LD_SO);
+  TEST_COMPARE (_dl_find_object (dlsym (handle, "environ"), &dlfo), 0);
+  TEST_COMPARE_STRING (basename (dlfo.dlfo_link_map->l_name), LIBC_SO);
+  TEST_COMPARE (_dl_find_object ((void *) 1, &dlfo), -1);
+  TEST_COMPARE (_dl_find_object ((void *) -1, &dlfo), -1);
+
   /* Verify that dlmopen creates a new namespace.  */
   void *dlmopen_handle = xdlmopen (LM_ID_NEWLM, LIBC_SO, RTLD_NOW);
   TEST_VERIFY (dlmopen_handle != handle);