From patchwork Tue Aug 20 23:26:22 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Phillip Lougher X-Patchwork-Id: 13770682 Received: from sxb1plsmtpa01-09.prod.sxb1.secureserver.net (sxb1plsmtpa01-09.prod.sxb1.secureserver.net [188.121.53.91]) (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 C417FA55 for ; Wed, 21 Aug 2024 00:11:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=188.121.53.91 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724199087; cv=none; b=sLMuRdQHafBxp7b5kAyw69rPW74GHEbEbIMqt7if2osJkxz1DWq/lGZyH6QkEj1yAUFDqTfeUUaym2m3M+BLlJRtCZ19lB75Frte+tdsPNW2bXWDZtfhdrggI8bP9FTbG+qz/88v3GazGG45CLv6/tTrqtL4Cu4OwitsY5RxTK4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724199087; c=relaxed/simple; bh=eJaeTVak1rt+uWU6m8O4EhDKO+Q3iCdDDptK1WJ+Kks=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=WyXi6/AGXjAD9PhH92km+x4LQRA6QcqAxndXjQIFFHNrEsV++/W+dTfxMz/XhWVPPNdUdGZBjzde3vaylVIaW3P4V1/oRhmhK644pc2garVueQwAAQIro/blyHH5G2E6bDkdKXfmMwDwHg9S6+xSTzPCq392FNtCyLNNSOfHQfM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=squashfs.org.uk; spf=pass smtp.mailfrom=squashfs.org.uk; arc=none smtp.client-ip=188.121.53.91 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=squashfs.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=squashfs.org.uk Received: from phoenix.fritz.box ([82.69.79.175]) by :SMTPAUTH: with ESMTPA id gYEdsqtlu3WfYgYFNshvcb; Tue, 20 Aug 2024 16:26:42 -0700 X-CMAE-Analysis: v=2.4 cv=JvU6r94C c=1 sm=1 tr=0 ts=66c52632 a=84ok6UeoqCVsigPHarzEiQ==:117 a=84ok6UeoqCVsigPHarzEiQ==:17 a=VwQbUJbxAAAA:8 a=FXvPX3liAAAA:8 a=6R2sW40mVC26G-UyxH8A:9 a=AjGcO6oz07-iQ99wixmX:22 a=UObqyxdv-6Yh2QiB9mM_:22 X-SECURESERVER-ACCT: phillip@squashfs.org.uk From: Phillip Lougher To: akpm@linux-foundation.org, brauner@kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: Phillip Lougher Subject: [PATCH 5/4] Squashfs: Ensure all readahead pages have been used Date: Wed, 21 Aug 2024 00:26:22 +0100 Message-Id: <20240820232622.19271-1-phillip@squashfs.org.uk> X-Mailer: git-send-email 2.39.2 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CMAE-Envelope: MS4xfG26RX2Z/qj8AIqoDmXkcgPabMADaY/QzpPxQrFw8jzfgUxug2x3Yrr4qy+kjlUzp1LLhM8ZXB0U90b0DsBUacWMJaMiMmbwBOnqevjLSPM2RStCxSxH IoTQpENi0oFnAVooFhD+HI9nqbnDxXOPAtl6ubLsBADgyAq4lj/CWuBLLQmyTjGcZ10qdZyItO8vkptohwSCeYOxX4Q5RN0uoY2tKlI3s+POtNRwdN0HJywY /bSuZv+3dkmsd9hAgsLaDILA70RR8ZJsfyoGIQLl4VHaEDdfZ+KpM5NdQoe8rYXVZ4CnSdub7Spm4yfV7by+zx9YXxpA7G1nCmGvTuunfHyyUsEDBhnCLR7O YYuP4HTs In the recent work to remove page->index, a sanity check that ensured all the readhead pages were covered by the Squashfs data block was removed [1]. To avoid any regression, this commit adds the sanity check back in an equivalent way. Namely the page actor will now return error if any pages are unused after completion. [1] https://lore.kernel.org/all/20240818235847.170468-3-phillip@squashfs.org.uk/ Signed-off-by: Phillip Lougher --- fs/squashfs/file.c | 4 ++-- fs/squashfs/file_direct.c | 2 +- fs/squashfs/page_actor.h | 6 +++++- 3 files changed, 8 insertions(+), 4 deletions(-) diff --git a/fs/squashfs/file.c b/fs/squashfs/file.c index 5a3745e52025..21aaa96856c1 100644 --- a/fs/squashfs/file.c +++ b/fs/squashfs/file.c @@ -535,7 +535,7 @@ static int squashfs_readahead_fragment(struct page **page, last_page = squashfs_page_actor_free(actor); - if (copied == expected) { + if (copied == expected && !IS_ERR(last_page)) { /* Last page (if present) may have trailing bytes not filled */ bytes = copied % PAGE_SIZE; if (bytes && last_page) @@ -625,7 +625,7 @@ static void squashfs_readahead(struct readahead_control *ractl) last_page = squashfs_page_actor_free(actor); - if (res == expected) { + if (res == expected && !IS_ERR(last_page)) { int bytes; /* Last page (if present) may have trailing bytes not filled */ diff --git a/fs/squashfs/file_direct.c b/fs/squashfs/file_direct.c index 646d4d421f99..22251743fadf 100644 --- a/fs/squashfs/file_direct.c +++ b/fs/squashfs/file_direct.c @@ -80,7 +80,7 @@ int squashfs_readpage_block(struct page *target_page, u64 block, int bsize, if (res < 0) goto mark_errored; - if (res != expected) { + if (res != expected || IS_ERR(last_page)) { res = -EIO; goto mark_errored; } diff --git a/fs/squashfs/page_actor.h b/fs/squashfs/page_actor.h index c6d837f0e9ca..f770a906c2c6 100644 --- a/fs/squashfs/page_actor.h +++ b/fs/squashfs/page_actor.h @@ -37,7 +37,11 @@ static inline struct page *squashfs_page_actor_free(struct squashfs_page_actor * kfree(actor->tmp_buffer); kfree(actor); - return last_page; + + if (actor->next_page == actor->pages) + return last_page; + else + return ERR_PTR(-EIO); } static inline void *squashfs_first_page(struct squashfs_page_actor *actor) {