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 13F6DAD48 for ; Wed, 4 Jan 2023 16:26:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 81564C433EF; Wed, 4 Jan 2023 16:26:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672849570; bh=2ggg8c2Xye8irSg9Anz7c2jzhmN6TIIeT0IWYrrQExA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aJOgP7k34prtPyOEyYmXXtxbpf7JFMbYZMdEhP5omN9abYgeYpnFqm4QIxlS/GM5n NTE8RAQz4hgsES81b6IF+s5uOUdKIQXKRMMnBajm1AA8hNLfmJKnLwn3YH1icxnkkW 3h+6ph2q7GCDlN/aL3k6aEdFHXmp285f+AEmztBA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Helge Deller Subject: [PATCH 6.0 121/177] parisc: Fix locking in pdc_iodc_print() firmware call Date: Wed, 4 Jan 2023 17:06:52 +0100 Message-Id: <20230104160511.308769907@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230104160507.635888536@linuxfoundation.org> References: <20230104160507.635888536@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: Helge Deller commit 7236aae5f81f3efbd93d0601e74fc05994bc2580 upstream. Utilize pdc_lock spinlock to protect parallel modifications of the iodc_dbuf[] buffer, check length to prevent buffer overflow of iodc_dbuf[], drop the iodc_retbuf[] buffer and fix some wrong indentings. Signed-off-by: Helge Deller Cc: # 6.0+ Signed-off-by: Greg Kroah-Hartman --- arch/parisc/kernel/firmware.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/arch/parisc/kernel/firmware.c b/arch/parisc/kernel/firmware.c index 6a7e315bcc2e..a115315d88e6 100644 --- a/arch/parisc/kernel/firmware.c +++ b/arch/parisc/kernel/firmware.c @@ -1288,9 +1288,8 @@ void pdc_io_reset_devices(void) #endif /* defined(BOOTLOADER) */ -/* locked by pdc_console_lock */ -static int __attribute__((aligned(8))) iodc_retbuf[32]; -static char __attribute__((aligned(64))) iodc_dbuf[4096]; +/* locked by pdc_lock */ +static char iodc_dbuf[4096] __page_aligned_bss; /** * pdc_iodc_print - Console print using IODC. @@ -1307,6 +1306,9 @@ int pdc_iodc_print(const unsigned char *str, unsigned count) unsigned int i; unsigned long flags; + count = min_t(unsigned int, count, sizeof(iodc_dbuf)); + + spin_lock_irqsave(&pdc_lock, flags); for (i = 0; i < count;) { switch(str[i]) { case '\n': @@ -1322,12 +1324,11 @@ int pdc_iodc_print(const unsigned char *str, unsigned count) } print: - spin_lock_irqsave(&pdc_lock, flags); - real32_call(PAGE0->mem_cons.iodc_io, - (unsigned long)PAGE0->mem_cons.hpa, ENTRY_IO_COUT, - PAGE0->mem_cons.spa, __pa(PAGE0->mem_cons.dp.layers), - __pa(iodc_retbuf), 0, __pa(iodc_dbuf), i, 0); - spin_unlock_irqrestore(&pdc_lock, flags); + real32_call(PAGE0->mem_cons.iodc_io, + (unsigned long)PAGE0->mem_cons.hpa, ENTRY_IO_COUT, + PAGE0->mem_cons.spa, __pa(PAGE0->mem_cons.dp.layers), + __pa(pdc_result), 0, __pa(iodc_dbuf), i, 0); + spin_unlock_irqrestore(&pdc_lock, flags); return i; } @@ -1354,10 +1355,11 @@ int pdc_iodc_getc(void) real32_call(PAGE0->mem_kbd.iodc_io, (unsigned long)PAGE0->mem_kbd.hpa, ENTRY_IO_CIN, PAGE0->mem_kbd.spa, __pa(PAGE0->mem_kbd.dp.layers), - __pa(iodc_retbuf), 0, __pa(iodc_dbuf), 1, 0); + __pa(pdc_result), 0, __pa(iodc_dbuf), 1, 0); ch = *iodc_dbuf; - status = *iodc_retbuf; + /* like convert_to_wide() but for first return value only: */ + status = *(int *)&pdc_result; spin_unlock_irqrestore(&pdc_lock, flags); if (status == 0) -- 2.39.0