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 2EC3B881F for ; Fri, 10 Mar 2023 14:43:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 96919C433EF; Fri, 10 Mar 2023 14:43:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678459387; bh=uIHANc4/Iw2UAmASUZe+EttDEtN+24A7thprh1Ird0k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ru8GgaqT9DW+AAEw2vnXGJPJ6zjb7Uny9WQDCasnZ72KrkJxZCNop6/jaWUyJR2ML TtJbD3/Ep4kn72rL9wC6X1A173KgcuoJtN7dQKb92OD89zdou7RCq0mbEHiHQ2J125 BbKUnNebS5PyoT16bfJhqcQ2OP2dNsVm1kYbJMng= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alan Stern , Kees Cook , Sasha Levin Subject: [PATCH 5.4 344/357] USB: ene_usb6250: Allocate enough memory for full object Date: Fri, 10 Mar 2023 14:40:33 +0100 Message-Id: <20230310133749.851743776@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310133733.973883071@linuxfoundation.org> References: <20230310133733.973883071@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Kees Cook [ Upstream commit ce33e64c1788912976b61314b56935abd4bc97ef ] The allocation of PageBuffer is 512 bytes in size, but the dereferencing of struct ms_bootblock_idi (also size 512) happens at a calculated offset within the allocation, which means the object could potentially extend beyond the end of the allocation. Avoid this case by just allocating enough space to catch any accesses beyond the end. Seen with GCC 13: ../drivers/usb/storage/ene_ub6250.c: In function 'ms_lib_process_bootblock': ../drivers/usb/storage/ene_ub6250.c:1050:44: warning: array subscript 'struct ms_bootblock_idi[0]' is partly outside array bounds of 'unsigned char[512]' [-Warray-bounds=] 1050 | if (le16_to_cpu(idi->wIDIgeneralConfiguration) != MS_IDI_GENERAL_CONF) | ^~ ../include/uapi/linux/byteorder/little_endian.h:37:51: note: in definition of macro '__le16_to_cpu' 37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x)) | ^ ../drivers/usb/storage/ene_ub6250.c:1050:29: note: in expansion of macro 'le16_to_cpu' 1050 | if (le16_to_cpu(idi->wIDIgeneralConfiguration) != MS_IDI_GENERAL_CONF) | ^~~~~~~~~~~ In file included from ../drivers/usb/storage/ene_ub6250.c:5: In function 'kmalloc', inlined from 'ms_lib_process_bootblock' at ../drivers/usb/storage/ene_ub6250.c:942:15: ../include/linux/slab.h:580:24: note: at offset [256, 512] into object of size 512 allocated by 'kmalloc_trace' 580 | return kmalloc_trace( | ^~~~~~~~~~~~~~ 581 | kmalloc_caches[kmalloc_type(flags)][index], | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 582 | flags, size); | ~~~~~~~~~~~~ Cc: Alan Stern Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20230204183546.never.849-kees@kernel.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/storage/ene_ub6250.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/storage/ene_ub6250.c b/drivers/usb/storage/ene_ub6250.c index 9c984f3c7248a..b076260a2ca49 100644 --- a/drivers/usb/storage/ene_ub6250.c +++ b/drivers/usb/storage/ene_ub6250.c @@ -938,7 +938,7 @@ static int ms_lib_process_bootblock(struct us_data *us, u16 PhyBlock, u8 *PageDa struct ms_lib_type_extdat ExtraData; struct ene_ub6250_info *info = (struct ene_ub6250_info *) us->extra; - PageBuffer = kmalloc(MS_BYTES_PER_PAGE, GFP_KERNEL); + PageBuffer = kzalloc(MS_BYTES_PER_PAGE * 2, GFP_KERNEL); if (PageBuffer == NULL) return (u32)-1; -- 2.39.2