From: Josef Bacik <josef@redhat.com>
To: linux-btrfs@vger.kernel.org
Subject: [PATCH] Btrfs: set trans to null in reserve_metadata_bytes if we commit the transaction
Date: Tue, 26 Oct 2010 12:54:30 -0400 [thread overview]
Message-ID: <1288112070-2676-1-git-send-email-josef@redhat.com> (raw)
btrfs_commit_transaction will free our trans, but because we pass trans to
shrink_delalloc we could possibly have a use after free situation. So instead
if we commit the transaction, set trans to null and set committed to true so we
don't keep trying to commit a transaction. This fixes a panic I could reproduce
at will. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
---
fs/btrfs/extent-tree.c | 9 ++++++---
1 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 180a501..e2dfd4a 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3157,6 +3157,7 @@ static int reserve_metadata_bytes(struct btrfs_trans_handle *trans,
int retries = 0;
int ret = 0;
bool reserved = false;
+ bool committed = false;
again:
ret = -ENOSPC;
@@ -3249,17 +3250,19 @@ again:
goto out;
ret = -EAGAIN;
- if (trans)
+ if (trans || committed)
goto out;
-
ret = -ENOSPC;
trans = btrfs_join_transaction(root, 1);
if (IS_ERR(trans))
goto out;
ret = btrfs_commit_transaction(trans, root);
- if (!ret)
+ if (!ret) {
+ trans = NULL;
+ committed = true;
goto again;
+ }
out:
if (reserved) {
--
1.6.6.1
reply other threads:[~2010-10-26 16:54 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1288112070-2676-1-git-send-email-josef@redhat.com \
--to=josef@redhat.com \
--cc=linux-btrfs@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).