From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out203-205-221-233.mail.qq.com (out203-205-221-233.mail.qq.com [203.205.221.233]) (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 590F53CF5E for ; Wed, 14 Aug 2024 09:32:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=203.205.221.233 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723627926; cv=none; b=pxZqx6XVCHZGLgbUjitcdxRsa6F7cZUqYrt3hUucXBrKQrstolZaIavMKvkSb/gaawC+GmqwBA2bm69AK7rWipzeze+4HoxQqoMM66KnuU+vveCmMxyKz352wt2LzW3qWqRkzNACC5hXHYX5uDdfCw9zHh6g5p6rN+PQlK3FczQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723627926; c=relaxed/simple; bh=7K1wMLTsX7xoRiV2EGWLfmS4OgCLAEdJHKEzZKgzXg8=; h=Message-ID:From:To:Cc:Subject:Date:In-Reply-To:References: MIME-Version; b=mSZnMKctZcpLbrU3pgYdzb4LA4t0IxRHrfXNcp5TnKDatUgV39CmIL8ejeQtAF2I0Qei90E4D7XJxo0vfBbxMnIT/WtVOaWYOrHrDYJxaRCfCUAw8rSJSJz1Jlt0B7K2ywEOLycVsXZn9xQgj/bjtpQYB5CsZXmegXKBaPWcid8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=qq.com; spf=pass smtp.mailfrom=qq.com; dkim=pass (1024-bit key) header.d=qq.com header.i=@qq.com header.b=xy87WijU; arc=none smtp.client-ip=203.205.221.233 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=qq.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=qq.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=qq.com header.i=@qq.com header.b="xy87WijU" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qq.com; s=s201512; t=1723627613; bh=BjWm5iNW6k12cGHitMBH2GV92WfnpXy1msZhJDgkWs0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=xy87WijUcu4+bjesxdbUY3w9WaKLHUkaeLDT12HViYsBQLTHNPgsoCdxYdt5Z1BH5 56FO6suFDqTbXe5XtkmBw2FwJZj4AzpbcNyysQ/L+obzOSUeAQSug284zXj/TekazX 5+lBqJfFnPHVneqE1fFBmMODm3pwMLjjyIyfScn4= Received: from pek-lxu-l1.wrs.com ([111.198.225.4]) by newxmesmtplogicsvrsza29-0.qq.com (NewEsmtp) with SMTP id 6B395873; Wed, 14 Aug 2024 17:26:51 +0800 X-QQ-mid: xmsmtpt1723627611t4ll7hh0p Message-ID: X-QQ-XMAILINFO: NY/MPejODIJVIqbu1gSDHSOAM7fPuif85TmEWB2TZ/Wuk46c2p3Ue3SwYhvTCM 078wlgS2zKbB2pBY1RmVW/mDZc60oby8r+toV66u3XokAvkp0m2C9fyAFe4OrNfCerg0Xv6Uz+QW FJ6EzK151PdY+SKkqcFYg04Opt3+Zm/XktJySn68uGz5GxrQfJsu/NV3hBpDRmhcvgIede8wEQPX rFGnPSG7AfLEcyxW50I3l8m5iSwzrfIxB2bQ9CxUf7DrQJoRzVCxEC3B5zBFppQvnh7T+iJ3Stj1 OcCDQEvtGo9cE5xSzS2bJOWhuNqxRTL2U/g2Qw+2LC5KL7oVnb1r55VvXDzsygTCJl/KQyoHEtot UsqY3lIaGNU7jOBibiPN7pAgdO+rQrxpWS1ppTY68TD/bcKjjuh5QtGNveQSLElJDXOIfzDFmB75 yw9UhFv2Maj5NouzIA/lDxDvvt4RcXGLndq18yHpTfIWKN+N5h5cRDaVfSSJHrbOW7MruDovYIpV PvbpyUltyfaIPZTnOFbS6oAvVJ7a+T6aNsMaVgk1w0zUSpTQu9y+B7/YhDVL9DNCP6Y4LgNkJf25 5vypNHSdJSlyvx7JFd4BLBXblT7gtJG2ZkqMVVla+Bxv8kIjY3VQ9/1nB1qPQtpfYD2Q9kZxYAnW A3Ea1bp31NqTc6AhlYO7P9GKz5Sr+9wAli/4MdHX+klJlUHHnT039MRpY2oT3szgdhOofLt35KMO OoF1JUQ/NVb+KEH3RNMWOqv0os0RyZKEU/uyX3l0Jno5ZmOkjOtIQxwkL1tI+eDeQW7ytex1z8Qq KVhUsvhS7SqaxC13BhkBncXPVZMO1HrlN4+c6YQpW/Bsm6T5bN8x9sDIB2mW4PSlybMPrFA8saGF G6BYWkqUVsS/XyzFkQR2dFneWDdt1Vj/AmBJEFHwt9OZGD7yfZZrFoTrEde/QP3Q/ZC/9PIc+p X-QQ-XMRINFO: Mp0Kj//9VHAxr69bL5MkOOs= From: Edward Adam Davis To: syzbot+0b74d367d6e80661d6df@syzkaller.appspotmail.com Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [v9fs?] WARNING in v9fs_begin_writeback Date: Wed, 14 Aug 2024 17:26:52 +0800 X-OQ-MSGID: <20240814092651.1028802-2-eadavis@qq.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <0000000000007ec511061f00a7b2@google.com> References: <0000000000007ec511061f00a7b2@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit debug #syz test: upstream c0ecd6388360 diff --git a/fs/9p/vfs_dir.c b/fs/9p/vfs_dir.c index e0d34e4e9076..cb511d49e35a 100644 --- a/fs/9p/vfs_dir.c +++ b/fs/9p/vfs_dir.c @@ -218,8 +218,10 @@ int v9fs_dir_release(struct inode *inode, struct file *filp) if ((S_ISREG(inode->i_mode)) && (filp->f_mode & FMODE_WRITE)) retval = filemap_fdatawrite(inode->i_mapping); + printk("fid: %p, %s\n", fid, __func__); spin_lock(&inode->i_lock); - hlist_del(&fid->ilist); + if (refcount_read(&fid->count) == 1) + hlist_del(&fid->ilist); spin_unlock(&inode->i_lock); put_err = p9_fid_put(fid); retval = retval < 0 ? retval : put_err; diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c index 348cc90bf9c5..acee5f6570a5 100644 --- a/fs/9p/vfs_file.c +++ b/fs/9p/vfs_file.c @@ -52,6 +52,7 @@ int v9fs_file_open(struct inode *inode, struct file *file) omode = v9fs_uflags2omode(file->f_flags, v9fs_proto_dotu(v9ses)); fid = file->private_data; + printk("fid: %p, %s\n", fid, __func__); if (!fid) { fid = v9fs_fid_clone(file_dentry(file)); if (IS_ERR(fid)) @@ -80,6 +81,8 @@ int v9fs_file_open(struct inode *inode, struct file *file) file->private_data = fid; } + else + p9_fid_get(fid); #ifdef CONFIG_9P_FSCACHE if (v9ses->cache & CACHE_FSCACHE)