From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 066E035AABF; Tue, 26 Aug 2025 14:33:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756218807; cv=none; b=n3GceRcBAmDUkSAb61CCXLC//By38vYJ3m7nmxnfYpJvT5+P3IFGOPRZELl/C1VGD7mRGiJnj7iZTsmPcV0CWbUI261AMYgbIxFZ4luw7kHk3Z0Rt5Y09xyrxy9EfX+adBhu3qCjY2U27mtlnePXa49oWch4J//OXb7+pcQQ4Sc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756218807; c=relaxed/simple; bh=lhnBjVi4+2pIe1jep4sOsHFt5eiD+ou2Lsn52oZvdPU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Qi8nvJPHMFQ80gJvg1sxtmbQeeWTBkegoL2U2725eI3Y1upRabSa7+FU7SpQ0DQGOWLBoaqtx517DjdpN5GVfEyY8A9DWi1EsmCbwbi12VHOsnVkIIC7BMGFT0KkbqkTIEXIQxOL2SusSgInNQxDhmq/Q0lvWOAWDsUUTZkHw8A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=iLM87aEt; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="iLM87aEt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 89D8BC4CEF1; Tue, 26 Aug 2025 14:33:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1756218806; bh=lhnBjVi4+2pIe1jep4sOsHFt5eiD+ou2Lsn52oZvdPU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iLM87aEtbXOjOwZn8aqGtu2x2LK9iTO1lkxvtfbATPt5oC8lcpO1A3j9jWbKM6mlp EQRUOsE4UqEigrHgKq0JdrRNVi8C/C/LjcBlcQPfOnhMbBlVWVP3cR1b4XVhatXcev xbtiCoQa0oIiVtp8xkdgMzPt+8Zy7Bt9ch8CCt6M= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, zhangjian , Trond Myklebust , Sasha Levin Subject: [PATCH 5.4 140/403] NFS: Fix filehandle bounds checking in nfs_fh_to_dentry() Date: Tue, 26 Aug 2025 13:07:46 +0200 Message-ID: <20250826110910.623942587@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250826110905.607690791@linuxfoundation.org> References: <20250826110905.607690791@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust [ Upstream commit ef93a685e01a281b5e2a25ce4e3428cf9371a205 ] The function needs to check the minimal filehandle length before it can access the embedded filehandle. Reported-by: zhangjian Fixes: 20fa19027286 ("nfs: add export operations") Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin --- fs/nfs/export.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/fs/nfs/export.c b/fs/nfs/export.c index deecb67638aa..97b6fa0adb57 100644 --- a/fs/nfs/export.c +++ b/fs/nfs/export.c @@ -67,14 +67,21 @@ nfs_fh_to_dentry(struct super_block *sb, struct fid *fid, struct nfs4_label *label = NULL; struct nfs_fattr *fattr = NULL; struct nfs_fh *server_fh = nfs_exp_embedfh(fid->raw); - size_t fh_size = offsetof(struct nfs_fh, data) + server_fh->size; + size_t fh_size = offsetof(struct nfs_fh, data); const struct nfs_rpc_ops *rpc_ops; struct dentry *dentry; struct inode *inode; - int len = EMBED_FH_OFF + XDR_QUADLEN(fh_size); + int len = EMBED_FH_OFF; u32 *p = fid->raw; int ret; + /* Initial check of bounds */ + if (fh_len < len + XDR_QUADLEN(fh_size) || + fh_len > XDR_QUADLEN(NFS_MAXFHSIZE)) + return NULL; + /* Calculate embedded filehandle size */ + fh_size += server_fh->size; + len += XDR_QUADLEN(fh_size); /* NULL translates to ESTALE */ if (fh_len < len || fh_type != len) return NULL; -- 2.39.5