openwrtv4/target/linux/generic/pending-4.9/890-uart_optional_sysrq.patch
Stijn Tintel 2d02a4f5bd kernel: update 4.9 to 4.9.44
Refresh patches.
Adapt 704-phy-no-genphy-soft-reset.patch.
Remove brcm2708/950-0005-mm-Remove-the-PFN-busy-warning.patch.
Compile-tested on brcm2708/bcm2708 and x86/64.
Runtime-tested on brcm2708/bcm2708 and x86/64.

Fixes the following vulnerabilities:
- CVE-2017-7533
- CVE-2017-1000111
- CVE-2017-1000112

Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
2017-08-17 12:34:34 +02:00

40 lines
1.3 KiB
Diff

From: John Crispin <john@phrozen.org>
Subject: serial: do not accept sysrq characters via serial port
many embedded boards have a disconnected TTL level serial which can
generate some garbage that can lead to spurious false sysrq detects.
[john@phrozen.org: sent upstream 22.12.2016]
Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
include/linux/serial_core.h | 2 +-
lib/Kconfig.debug | 5 +++++
2 files changed, 6 insertions(+), 1 deletion(-)
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -448,7 +448,7 @@ extern void uart_handle_cts_change(struc
extern void uart_insert_char(struct uart_port *port, unsigned int status,
unsigned int overrun, unsigned int ch, unsigned int flag);
-#ifdef SUPPORT_SYSRQ
+#if defined(SUPPORT_SYSRQ) && defined(CONFIG_MAGIC_SYSRQ_SERIAL)
static inline int
uart_handle_sysrq_char(struct uart_port *port, unsigned int ch)
{
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -397,6 +397,11 @@ config MAGIC_SYSRQ_DEFAULT_ENABLE
This may be set to 1 or 0 to enable or disable them all, or
to a bitmask as described in Documentation/sysrq.txt.
+config MAGIC_SYSRQ_SERIAL
+ bool "Enable magic SysRq key over serial"
+ depends on MAGIC_SYSRQ
+ default y
+
config DEBUG_KERNEL
bool "Kernel debugging"
help