From patchwork Wed Aug 14 20:38:22 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13763935 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 17ADB1C688B for ; Wed, 14 Aug 2024 20:39:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723667978; cv=none; b=ny89auA8cSxpdmVHp8hD38W0OZ1Gnq+M9l56LSG+qTCSJPWOOQ5EAcIxr5Ummv/PC7J38UfQ6j3rkfbx1WCrcxOCP3Fg9VzjGs799R53nXOIEKM9wt5BrRkqvlrCOTH5uGkCgNdHL1GJ8Gi6R5yxpUkwPjSV1pcHdZ1TAZAi89c= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723667978; c=relaxed/simple; bh=fZBSvxMxbAQZkZtiGc4RF0+420hS/GpbQoVBSrmCKa8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=IcHm4EQ23u8sHqRAsc/vp3J9Mri/eBavltQu9SMAW8OdIA8DtLqo+nLfm8I9b9sfbUNhygquAaadiCHWi8BHxAhZqAPI/g0nPZlA6YybpBKluHksLOj7+ps5hofqiMPveIWCqBd5L4OmPriut/Mdp87gcRV57oQ7lmVWg5iiXys= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=cZGdWXSp; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="cZGdWXSp" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1723667974; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Wvz9YBrTPFQ9wVYP2d1umk84aV9uv83ek2O7Ma2LSP4=; b=cZGdWXSp8PdnYVqzJ7b4NkixfGE0bANjA2EiFDbbY7sNW5xcdkCmXzdIiIFhTxANr4GRmG GJ8/ipEduMLSLXpt7lvmezQBLlHhZ3EcfeWvi7gzRAQDSa9bnPAHyJq1CL/y6xmt4+ik9w TpYF+5D0uitU8Nt9vZ0duFnTsizCzXY= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-8-9QbQ7aiUNXWL2QCGcnXXHA-1; Wed, 14 Aug 2024 16:39:26 -0400 X-MC-Unique: 9QbQ7aiUNXWL2QCGcnXXHA-1 Received: from mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.15]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 4AA841954B10; Wed, 14 Aug 2024 20:39:19 +0000 (UTC) Received: from warthog.procyon.org.uk.com (unknown [10.42.28.30]) by mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 90C961955E8C; Wed, 14 Aug 2024 20:39:11 +0000 (UTC) From: David Howells To: Christian Brauner , Steve French , Matthew Wilcox Cc: David Howells , Jeff Layton , Gao Xiang , Dominique Martinet , Marc Dionne , Paulo Alcantara , Shyam Prasad N , Tom Talpey , Eric Van Hensbergen , Ilya Dryomov , netfs@lists.linux.dev, linux-afs@lists.infradead.org, linux-cifs@vger.kernel.org, linux-nfs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs@lists.linux.dev, linux-erofs@lists.ozlabs.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Christian Brauner , Gao Xiang Subject: [PATCH v2 02/25] cachefiles: Fix non-taking of sb_writers around set/removexattr Date: Wed, 14 Aug 2024 21:38:22 +0100 Message-ID: <20240814203850.2240469-3-dhowells@redhat.com> In-Reply-To: <20240814203850.2240469-1-dhowells@redhat.com> References: <20240814203850.2240469-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.15 Unlike other vfs_xxxx() calls, vfs_setxattr() and vfs_removexattr() don't take the sb_writers lock, so the caller should do it for them. Fix cachefiles to do this. Fixes: 9ae326a69004 ("CacheFiles: A cache that backs onto a mounted filesystem") Signed-off-by: David Howells cc: Christian Brauner cc: Gao Xiang cc: netfs@lists.linux.dev cc: linux-erofs@lists.ozlabs.org cc: linux-fsdevel@vger.kernel.org --- fs/cachefiles/xattr.c | 34 ++++++++++++++++++++++++++-------- 1 file changed, 26 insertions(+), 8 deletions(-) diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c index 4dd8a993c60a..7c6f260a3be5 100644 --- a/fs/cachefiles/xattr.c +++ b/fs/cachefiles/xattr.c @@ -64,9 +64,15 @@ int cachefiles_set_object_xattr(struct cachefiles_object *object) memcpy(buf->data, fscache_get_aux(object->cookie), len); ret = cachefiles_inject_write_error(); - if (ret == 0) - ret = vfs_setxattr(&nop_mnt_idmap, dentry, cachefiles_xattr_cache, - buf, sizeof(struct cachefiles_xattr) + len, 0); + if (ret == 0) { + ret = mnt_want_write_file(file); + if (ret == 0) { + ret = vfs_setxattr(&nop_mnt_idmap, dentry, + cachefiles_xattr_cache, buf, + sizeof(struct cachefiles_xattr) + len, 0); + mnt_drop_write_file(file); + } + } if (ret < 0) { trace_cachefiles_vfs_error(object, file_inode(file), ret, cachefiles_trace_setxattr_error); @@ -151,8 +157,14 @@ int cachefiles_remove_object_xattr(struct cachefiles_cache *cache, int ret; ret = cachefiles_inject_remove_error(); - if (ret == 0) - ret = vfs_removexattr(&nop_mnt_idmap, dentry, cachefiles_xattr_cache); + if (ret == 0) { + ret = mnt_want_write(cache->mnt); + if (ret == 0) { + ret = vfs_removexattr(&nop_mnt_idmap, dentry, + cachefiles_xattr_cache); + mnt_drop_write(cache->mnt); + } + } if (ret < 0) { trace_cachefiles_vfs_error(object, d_inode(dentry), ret, cachefiles_trace_remxattr_error); @@ -208,9 +220,15 @@ bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume) memcpy(buf->data, p, volume->vcookie->coherency_len); ret = cachefiles_inject_write_error(); - if (ret == 0) - ret = vfs_setxattr(&nop_mnt_idmap, dentry, cachefiles_xattr_cache, - buf, len, 0); + if (ret == 0) { + ret = mnt_want_write(volume->cache->mnt); + if (ret == 0) { + ret = vfs_setxattr(&nop_mnt_idmap, dentry, + cachefiles_xattr_cache, + buf, len, 0); + mnt_drop_write(volume->cache->mnt); + } + } if (ret < 0) { trace_cachefiles_vfs_error(NULL, d_inode(dentry), ret, cachefiles_trace_setxattr_error);