linux/kernel/events
Yabin Cui 02e184476e perf/core: Force USER_DS when recording user stack data
Perf can record user stack data in response to a synchronous request, such
as a tracepoint firing. If this happens under set_fs(KERNEL_DS), then we
end up reading user stack data using __copy_from_user_inatomic() under
set_fs(KERNEL_DS). I think this conflicts with the intention of using
set_fs(KERNEL_DS). And it is explicitly forbidden by hardware on ARM64
when both CONFIG_ARM64_UAO and CONFIG_ARM64_PAN are used.

So fix this by forcing USER_DS when recording user stack data.

Signed-off-by: Yabin Cui <yabinc@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 88b0193d94 ("perf/callchain: Force USER_DS when invoking perf_callchain_user()")
Link: http://lkml.kernel.org/r/20180823225935.27035-1-yabinc@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 14:01:46 +02:00
..
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
callchain.c treewide: convert ISO_8859-1 text comments to utf-8 2018-08-23 18:48:43 -07:00
core.c perf/core: Force USER_DS when recording user stack data 2018-09-10 14:01:46 +02:00
hw_breakpoint.c perf/hw_breakpoint: Enable breakpoint in modify_user_hw_breakpoint 2018-08-30 14:49:23 -03:00
internal.h perf: Make perf_callchain function static 2018-01-08 12:33:01 -03:00
ring_buffer.c Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-24 20:29:15 +08:00
uprobes.c Updates for v4.19: 2018-08-20 18:32:00 -07:00