linux-kernel - [PATCH 04/13] FS-Cache: Handle a new operation submitted against a killed object

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20150226140221.2387.88860.stgit@warthog.procyon.org.uk>
Date:	Thu, 26 Feb 2015 14:02:21 +0000
From:	David Howells <dhowells@...hat.com>
To:	linux-cachefs@...hat.com
Cc:	dhowells@...hat.com, linux-fsdevel@...r.kernel.org,
	linux-nfs@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH 04/13] FS-Cache: Handle a new operation submitted against a
 killed object

Reject new operations that are being submitted against an object if that
object has failed its lookup or creation states or has been killed by the
cache backend for some other reason, such as having been culled.

Signed-off-by: David Howells <dhowells@...hat.com>
---

 fs/fscache/object.c    |    2 ++
 fs/fscache/operation.c |    6 ++++++
 2 files changed, 8 insertions(+)

diff --git a/fs/fscache/object.c b/fs/fscache/object.c
index 12bb468bf0ae..9b79fc9a1464 100644
--- a/fs/fscache/object.c
+++ b/fs/fscache/object.c
@@ -610,6 +610,8 @@ static const struct fscache_state *fscache_lookup_failure(struct fscache_object
 	object->cache->ops->lookup_complete(object);
 	fscache_stat_d(&fscache_n_cop_lookup_complete);
 
+	set_bit(FSCACHE_OBJECT_KILLED_BY_CACHE, &object->flags);
+
 	cookie = object->cookie;
 	set_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
 	if (test_and_clear_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags))
diff --git a/fs/fscache/operation.c b/fs/fscache/operation.c
index dec6defe3be3..18658fffbba1 100644
--- a/fs/fscache/operation.c
+++ b/fs/fscache/operation.c
@@ -176,6 +176,9 @@ int fscache_submit_exclusive_op(struct fscache_object *object,
 		list_add_tail(&op->pend_link, &object->pending_ops);
 		fscache_stat(&fscache_n_op_pend);
 		ret = 0;
+	} else if (flags & BIT(FSCACHE_OBJECT_KILLED_BY_CACHE)) {
+		op->state = FSCACHE_OP_ST_CANCELLED;
+		ret = -ENOBUFS;
 	} else {
 		fscache_report_unexpected_submission(object, op, ostate);
 		op->state = FSCACHE_OP_ST_CANCELLED;
@@ -249,6 +252,9 @@ int fscache_submit_op(struct fscache_object *object,
 		list_add_tail(&op->pend_link, &object->pending_ops);
 		fscache_stat(&fscache_n_op_pend);
 		ret = 0;
+	} else if (flags & BIT(FSCACHE_OBJECT_KILLED_BY_CACHE)) {
+		op->state = FSCACHE_OP_ST_CANCELLED;
+		ret = -ENOBUFS;
 	} else {
 		fscache_report_unexpected_submission(object, op, ostate);
 		ASSERT(!fscache_object_is_active(object));

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/