flat: fix uninitialized ptr with shared libs
The new credentials code broke load_flat_shared_library() as it now uses
an uninitialized cred pointer.
Reported-by: Bernd Schmidt <bernds_cb1@t-online.de>
Tested-by: Bernd Schmidt <bernds_cb1@t-online.de>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: David Howells <dhowells@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 697f6b5..e92f229 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -828,15 +828,22 @@
if (IS_ERR(bprm.file))
return res;
+ bprm.cred = prepare_exec_creds();
+ res = -ENOMEM;
+ if (!bprm.cred)
+ goto out;
+
res = prepare_binprm(&bprm);
if (res <= (unsigned long)-4096)
res = load_flat_file(&bprm, libs, id, NULL);
- if (bprm.file) {
- allow_write_access(bprm.file);
- fput(bprm.file);
- bprm.file = NULL;
- }
+
+ abort_creds(bprm.cred);
+
+out:
+ allow_write_access(bprm.file);
+ fput(bprm.file);
+
return(res);
}