From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C0DE360A2601 for ; Thu, 12 Nov 2026 16:39:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=coo7c6ez; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=lCDGyKKY DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References :Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Unsubscribe-Post: List-Owner; bh=P2GAXQL+CRALZ6ktolsI+wkJgETtKYVg5/S1WwdnjP8=; b=coo7c6ezLHRqm8 Z5fxU7agNThzwhH/hz/xjtgURpYVdtMvi2RZ0kndZjpzk5CbS0UGhkP7RGGuh5B7+iOSpTUCG53rc fVtvm15roNFH2rUrst7gZaJaeuE5dhtGfoCv+Nx1zOt1Q8SN45KRR7LRh7bjdr6EYqaaop8EiU6sp ErIldCz12JxJTnTjArGabtTgNzQO1WTbzZrLz3scGI6ZL/AdWvx0nwbZvJMEMpSD66NrK1+KlTYuH cgb0ZJ8RqHVgEpfKyVJzU2hzSXSg6ubqp+jgxmRESE1rCOETbO6/pm5BOFPecBk0JMHl04qzChM+Z oU+nFSI83c/JbWSynwVA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xRXpO-0000000AdEG-0X2E; Thu, 12 Nov 2026 16:39:10 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xRXoJ-0000000AcaA-0kyb; Thu, 12 Nov 2026 16:38:03 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id DE86445050; Thu, 12 Nov 2026 16:38:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 460611F000C6; Thu, 12 Nov 2026 16:37:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794501482; bh=P2GAXQL+CRALZ6ktolsI+wkJgETtKYVg5/S1WwdnjP8=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=lCDGyKKYBC8Fs6CZs83hFW2kfQvIWzrbx55R2xhY23bPVejs4jP03UhTMbPYwkdFq 6QnSYzu3WeVqWx+Ar0edjh2cqOYYgzZqe/DZ5+wO5as7ByI7SvXh6bulOXMCzm12Eu kASOJRtSewIDlEzyPzzCY1AdAWX/EVv1Af43bEp/TzGRyu8tlqudESjSsVdhjFBpbc gPakCksrVRPklHGcZFFoijOXgWwbOd12WzoiKbEcn8WBWaclGOUWPLB0E7xNqJ2ACq pLxZ0JI0ySEeRWv9k3TGyTyi5fx1EhNiDCo/FW3wSZW06JeHOMYn6a8E5q27+Wxlkv sJ5MuJnwBIRmA== From: Christian Brauner Date: Thu, 12 Nov 2026 17:37:08 +0100 Subject: [PATCH RFC 2/4] sh/crash_dump: check ioremap() in copy_oldmem_page() X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261112-work-procfs-oldmem-v1-2-ecdcafd99265@kernel.org> References: <20261112-work-procfs-oldmem-v1-0-ecdcafd99265@kernel.org> In-Reply-To: <20261112-work-procfs-oldmem-v1-0-ecdcafd99265@kernel.org> To: linux-fsdevel@vger.kernel.org Cc: Linus Torvalds , Breno Leitao , Chris Mason , Thomas Gleixner , x86@kernel.org, kexec@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org, David Hildenbrand , "Christian Brauner (Amutable)" , stable@vger.kernel.org X-Mailer: b4 0.17-dev-ce4c1 X-Developer-Signature: v=1; a=openpgp-sha256; l=1003; i=brauner@kernel.org; h=from:subject:message-id; bh=q6FpWygcFHpF/XYp2OeRsrvJ/y8aBzOdxnvKzJI5CUg=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWR9fR2ZXPfx+k0nz9UdCcufZi5bEfNP4/gkpZxGBe7ty U5mqhMMO0pZGMS4GGTFFFkc2k3C5ZbzVGw2ytSAmcPKBDKEgYtTACbCX8DIsO3Srhdppo67Nmsn CMzvSEg8stFmw5lYXa2tcWbPH7+Ou8Pwv/BN4KTdgsEMAr8vHor9ftTa73Deda0PH0/LeesVzJZ gZQIA X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 copy_oldmem_page() maps a page of the old kernel with ioremap() and copies from it without checking whether the mapping worked. If it didn't, the copy reads from an offset into the NULL page. Return -ENOMEM like the other architectures do. read_from_oldmem() turns that into -EFAULT like any other short copy. Fixes: 4d5ade5b29c6 ("sh: kdump support.") Cc: stable@vger.kernel.org Signed-off-by: Christian Brauner (Amutable) --- arch/sh/kernel/crash_dump.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/sh/kernel/crash_dump.c b/arch/sh/kernel/crash_dump.c index 19ce6a950aaca..85c0e58f1a59f 100644 --- a/arch/sh/kernel/crash_dump.c +++ b/arch/sh/kernel/crash_dump.c @@ -20,6 +20,9 @@ ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, return 0; vaddr = ioremap(pfn << PAGE_SHIFT, PAGE_SIZE); + if (!vaddr) + return -ENOMEM; + csize = copy_to_iter(vaddr + offset, csize, iter); iounmap(vaddr); -- 2.53.0