linux-stable/kernel/debug
Sumit Garg a0a4e00a41 kdb: Make memory allocations more robust
commit 93f7a6d818 upstream.

Currently kdb uses in_interrupt() to determine whether its library
code has been called from the kgdb trap handler or from a saner calling
context such as driver init. This approach is broken because
in_interrupt() alone isn't able to determine kgdb trap handler entry from
normal task context. This can happen during normal use of basic features
such as breakpoints and can also be trivially reproduced using:
echo g > /proc/sysrq-trigger

We can improve this by adding check for in_dbg_master() instead which
explicitly determines if we are running in debugger context.

Cc: stable@vger.kernel.org
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/1611313556-4004-1-git-send-email-sumit.garg@linaro.org
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-03 18:22:36 +01:00
..
kdb kdb: Make memory allocations more robust 2021-03-03 18:22:36 +01:00
Makefile
debug_core.c kgdb: Make "kgdbcon" work properly with "kgdb_earlycon" 2020-11-05 11:06:55 +01:00
debug_core.h
gdbstub.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h> 2017-03-02 08:42:29 +01:00