ostree/libmount-unref.patch
2017-02-23 11:05:00 -05:00

44 lines
1.3 KiB
Diff

From 4c3ef23b59c870281a75424c74ec0b6b5a4ae5e8 Mon Sep 17 00:00:00 2001
From: Colin Walters <walters@verbum.org>
Date: Thu, 23 Feb 2017 09:40:17 -0500
Subject: [PATCH] deploy: Correctly use libmount unref() calls rather than
free()
We saw a random ostree SEGV start popping up in our CI environment:
https://github.com/projectatomic/rpm-ostree/pull/641#issuecomment-281870424
Looking at this code more and comparing it to what util-linux does, I noticed we
had a write-after-free, since `mnt_unref_table()` will invoke
`mnt_unref_cache()` on its cache, and that function does:
```
if (cache) {
cache->rfcount--;
```
unconditionally.
Fix this by using `unref()`.
---
src/libostree/ostree-sysroot-deploy.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/src/libostree/ostree-sysroot-deploy.c b/src/libostree/ostree-sysroot-deploy.c
index cb5a461..5a3f6d8 100644
--- a/src/libostree/ostree-sysroot-deploy.c
+++ b/src/libostree/ostree-sysroot-deploy.c
@@ -1692,8 +1692,8 @@ is_ro_mount (const char *path)
fs = mnt_table_find_target(tb, path, MNT_ITER_BACKWARD);
is_mount = fs && mnt_fs_get_target (fs);
- mnt_free_cache (cache);
- mnt_free_table (tb);
+ mnt_unref_cache (cache);
+ mnt_unref_table (tb);
if (!is_mount)
return FALSE;
--
2.9.3