Hello, enclosed is a patch that prevents tar from dereferencing NULL with --listed-incremental. The bug was introduced in 2b1bffb. Original bug report, including a reproducer and backtrace, is located in our bugzilla:
https://bugzilla.redhat.com/635318 I must admit I don't understand much the code, but the attached patch at least solves the reported crash. Thanks in advance for review! Kamil
From 0d96d7d41737f8a92484ec9afef0c430fdc07e0a Mon Sep 17 00:00:00 2001 From: Kamil Dudka <[email protected]> Date: Mon, 20 Sep 2010 09:41:08 +0200 Subject: [PATCH] tar: do not crash with --listed-incremental originally reported at https://bugzilla.redhat.com/635318 * src/incremen.c (append_incremental_renames): Avoid invalid dereference in case dir == NULL. --- src/incremen.c | 7 +++++-- 1 files changed, 5 insertions(+), 2 deletions(-) diff --git a/src/incremen.c b/src/incremen.c index c6d4f4c..2bd3f4d 100644 --- a/src/incremen.c +++ b/src/incremen.c @@ -893,8 +893,11 @@ append_incremental_renames (struct directory *dir) if (obstack_object_size (&stk) != size) { obstack_1grow (&stk, 0); - dumpdir_free (dir->dump); - dir->dump = dumpdir_create (obstack_finish (&stk)); + if (dir) + { + dumpdir_free (dir->dump); + dir->dump = dumpdir_create (obstack_finish (&stk)); + } } obstack_free (&stk, NULL); } -- 1.7.2.3
