From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 E1C2043D510; Tue, 21 Jul 2026 22:43:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784673839; cv=none; b=e6ge6vx5IX1yvl2Qon0l0q8mBEk1w3PuC14msqN/73DdFYkZZWsewDywAElNigBhwBXZrrLG5kPmCkvLRSUijOHYwua+LejOzs8eZfVZ07YyLbGu/LF7yzMgWeRaIlYasT0P/+nfozQN/u5fA5Bniq78j+xpM95MqXGyzmTIUGE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784673839; c=relaxed/simple; bh=8rGYmSk5owK58SCjCDIztuWN94BN5pr23rGKXhbkeYA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gECubxW/3krrL3C7+kut01jDb4SHNYn/wFWOV3ga4hIG/MgJ64GtVUq5eiwRcOkq4qyEdthTaKFkmTeXJnifkLvDS3TJFhzyynGgcDQYeVwsKG+6HvvXxfibk6ZF4IQ2z5xKaQcrBnO1o8WBbtUhRNHZIjsUtUCGWhutaxvrV6Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=b59QC5uJ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="b59QC5uJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4B1361F000E9; Tue, 21 Jul 2026 22:43:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784673837; bh=h8sSbqaA7WidDJchwLoYmlzzveI4IeTEuOmP4sfTtqI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=b59QC5uJy2jTJpWzPfeYs1GThgmXus8EK1JNdIjFhauf9oWkB74W1IuFI6J0+q7ZS Ssoj3MTISPemKG3HWWCZyb8jRUJORBDXOjbV/M4Zfi05S/D5mlDbQXCNoxgRUDYuNv Zs9/DSmpNuhxkSfHkvk1E21leBtE+jV5pssB/hzE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yadan Fan , Thomas Bogendoerfer , Sasha Levin Subject: [PATCH 5.10 271/699] MIPS: mm: Fix out-of-bounds write in maar_res_walk() Date: Tue, 21 Jul 2026 17:20:30 +0200 Message-ID: <20260721152401.813753405@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152355.667394603@linuxfoundation.org> References: <20260721152355.667394603@linuxfoundation.org> User-Agent: quilt/0.69 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 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yadan Fan [ Upstream commit 1b001b16bc88f3f7817e228acfd91ee01bdcfcce ] maar_res_walk() uses wi->num_cfg as the index into the fixed-size wi->cfg array, but checks whether the array is full only after it has filled the selected entry. If walk_system_ram_range() reports more than 16 memory ranges, the overflow call writes one struct maar_config past the end of the array before WARN_ON() prevents num_cfg from advancing. Move the full-array check before taking the array slot and return non-zero when the scratch array is full, so walk_system_ram_range() terminates the walk instead of invoking the callback for further ranges. Fixes: a5718fe8f70f ("MIPS: mm: Drop boot_mem_map") Signed-off-by: Yadan Fan Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin --- arch/mips/mm/init.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c index 32e7b869a29105..bd819340d1ffae 100644 --- a/arch/mips/mm/init.c +++ b/arch/mips/mm/init.c @@ -277,9 +277,15 @@ static int maar_res_walk(unsigned long start_pfn, unsigned long nr_pages, void *data) { struct maar_walk_info *wi = data; - struct maar_config *cfg = &wi->cfg[wi->num_cfg]; + struct maar_config *cfg; unsigned int maar_align; + /* Ensure we don't overflow the cfg array */ + if (WARN_ON(wi->num_cfg >= ARRAY_SIZE(wi->cfg))) + return -1; + + cfg = &wi->cfg[wi->num_cfg]; + /* MAAR registers hold physical addresses right shifted by 4 bits */ maar_align = BIT(MIPS_MAAR_ADDR_SHIFT + 4); @@ -288,9 +294,7 @@ static int maar_res_walk(unsigned long start_pfn, unsigned long nr_pages, cfg->upper = ALIGN_DOWN(PFN_PHYS(start_pfn + nr_pages), maar_align) - 1; cfg->attrs = MIPS_MAAR_S; - /* Ensure we don't overflow the cfg array */ - if (!WARN_ON(wi->num_cfg >= ARRAY_SIZE(wi->cfg))) - wi->num_cfg++; + wi->num_cfg++; return 0; } -- 2.53.0