From patchwork Fri Feb 2 11:01:31 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Amir Goldstein X-Patchwork-Id: 13542748 Received: from mail-wr1-f52.google.com (mail-wr1-f52.google.com [209.85.221.52]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F316A1AAD0; Fri, 2 Feb 2024 11:01:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.52 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706871702; cv=none; b=WcGFwxU5tFZ16s+m4oeRWFxTeZ13zupWPvGRMhEaaLfI8PtWqYcAqveTJJkuOUuPGoFnhyndouJFMxapqyGfm788OfI42toNTu+oc779qpsQgck7FzbRlB169HiYA5BDRgqkK/3XsKZ5GEV+InpJHd/C8hOAjDcMHdVckS6lm9c= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706871702; c=relaxed/simple; bh=hkpeaV8u9rmcrplO8sPRlu+Yw3e2erGl5bp7bG2DOfw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=TFTbWElt7asO8f66GfFvAc8CJTSBfTg9eVy7g4u9kOCOT+M8G5gQIp8Sx73LnYX7Qav3v035vSYaqprlmwCAPxgIYobo87+kOHEpIAx6N+NePncVGmjTu9wGfLykPrxNZLI+qGFZifw+wB9bYhao9r4MKJy7kZyeV1JmTuERYRA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=FeL6hCmb; arc=none smtp.client-ip=209.85.221.52 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="FeL6hCmb" Received: by mail-wr1-f52.google.com with SMTP id ffacd0b85a97d-33b1b95df3bso624581f8f.0; Fri, 02 Feb 2024 03:01:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1706871699; x=1707476499; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=CzmNNtzVgqF5REdEifiI9TBBkr8i4rasQbivXnMhC5s=; b=FeL6hCmb3/6na+gdBYOsw+A2lgrlWL9nH5/whv9CwM3Q9bopJyrVsiBvwYTv2sCqWT FtbSeq3uzf5hf9CtllcRt1kkGuIoAqzK7Nt8q3fsaFxiLG4D7BnOHB3x6YEi1nloOqrU lR1a4uXaiic5AsaOXEkNw9ZVtPj1mZE8eRRCmMIH2lFs6VsUhSevVUMjKEqWr+0JG9uS oPmD1ojABWYnZ2UzcYGhnAoF5f2fg5+0EmIVqeoqRfFLk2lVpHSpkLu11s1JGRlEmoRS 4z4kqgUf/zBERszZTq+aFODyJUA73l01HDbXuTLSW4CTWqXac90VIyTnN2fTqH/4CWPM Bbpw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1706871699; x=1707476499; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=CzmNNtzVgqF5REdEifiI9TBBkr8i4rasQbivXnMhC5s=; b=LIdw4U+1Wuv95tIWC1dkf75iyi53av/LMedGttPRAT54ufOgubsxBLa/ix42pQraxC 3UKtnHVWVjMGrYrvJlJJ/Q3tTycNKzmL9iPktAONvHpxUHs4HcFxHoUpcPv6uw/r2xrP WuvlB9h1Ni4eFM9u5pmf1WWyNG1p+KHHr5KFXPVYY+9USbCxjpQ8ky1cgnCkkaPMY90S YJ8DtHf0DB2ynFXe8w2u/1Quep3uJFrJQ3JWgsfiv7Hk8HC/K719p9VaNkXkiErX8nwq wCdjQePKr9k2He62U4J0UeMqzUNh4nIn9pb2kbg2IOfGaumXCPQYSdHAUwzOpiVa8oOm qb2g== X-Gm-Message-State: AOJu0YyvJO2dWeUDKnbJXV7H/+1Kf3jfTNktI8ZP9RC1iXPSN7W+zlIv +LKnKr2R9vSOjsIOCYAGH6M1sQeAOn2M/9xbZZcMFXspoY/i1JaGHOy/Ostr X-Google-Smtp-Source: AGHT+IGQp/TFEs6vLHnvcpQ9wYgdEEgTUtqawicb5Y+dLtAyDjU6To3cL+VhE5Zuzz5cC/lNV8zKBg== X-Received: by 2002:a5d:4211:0:b0:33b:1a6b:eeea with SMTP id n17-20020a5d4211000000b0033b1a6beeeamr2515307wrq.51.1706871699076; Fri, 02 Feb 2024 03:01:39 -0800 (PST) X-Forwarded-Encrypted: i=0; AJvYcCU1njgsFsNu3ozm6VYL92LQ5nas6y8HlqyjAI0+IO01MSu0lp61gFEqpgprJwU3hyCVOSHczUtPTDrN3Gdo2ROG9t0wswdF6/ww6XHdWzuyelHzmUk7g3dinqRwykPqhsUtat5p6TRkjyXiuzamooobLXhBDmFAWtegjLG6Bf7+jJBWr4snAstJ6YHlauZkXoq6EzE818Ip5ri0MMvjQrneVyMdtCAK/hA9z3AJgvuJm17xT0CChHEec316qVxdCPufruO/4bTTJngRsDqG Received: from amir-ThinkPad-T480.lan (46-117-242-41.bb.netvision.net.il. [46.117.242.41]) by smtp.gmail.com with ESMTPSA id a13-20020a5d4d4d000000b0033b0924543asm1654180wru.108.2024.02.02.03.01.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 02 Feb 2024 03:01:38 -0800 (PST) From: Amir Goldstein To: Miklos Szeredi Cc: Al Viro , Christian Brauner , Stefan Berger , Mimi Zohar , linux-unionfs@vger.kernel.org, linux-integrity@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH 1/2] fs: make file_dentry() a simple accessor Date: Fri, 2 Feb 2024 13:01:31 +0200 Message-Id: <20240202110132.1584111-2-amir73il@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240202110132.1584111-1-amir73il@gmail.com> References: <20240202110132.1584111-1-amir73il@gmail.com> Precedence: bulk X-Mailing-List: linux-integrity@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 file_dentry() is a relic from the days that overlayfs was using files with a "fake" path, meaning, f_path on overlayfs and f_inode on underlying fs. In those days, file_dentry() was needed to get the underlying fs dentry that matches f_inode. Files with "fake" path should not exist nowadays, so make file_dentry() a simple accessor and use an assertion to make sure that file_dentry() was not papering over filesystem bugs. Signed-off-by: Amir Goldstein Tested-by: Stefan Berger --- include/linux/fs.h | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/include/linux/fs.h b/include/linux/fs.h index 023f37c60709..de9aa86d2624 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1078,9 +1078,20 @@ static inline struct inode *file_inode(const struct file *f) return f->f_inode; } +/* + * file_dentry() is a relic from the days that overlayfs was using files with a + * "fake" path, meaning, f_path on overlayfs and f_inode on underlying fs. + * In those days, file_dentry() was needed to get the underlying fs dentry that + * matches f_inode. + * Files with "fake" path should not exist nowadays, so use an assertion to make + * sure that file_dentry() was not papering over filesystem bugs. + */ static inline struct dentry *file_dentry(const struct file *file) { - return d_real(file->f_path.dentry, file_inode(file)); + struct dentry *dentry = file->f_path.dentry; + + WARN_ON_ONCE(d_inode(dentry) != file_inode(file)); + return dentry; } struct fasync_struct {