linux-stable/kernel/trace
Steven Rostedt (VMware) 66f833dbed ring-buffer: Mask out the info bits when returning buffer page length
commit 45d8b80c2a upstream.

Two info bits were added to the "commit" part of the ring buffer data page
when returned to be consumed. This was to inform the user space readers that
events have been missed, and that the count may be stored at the end of the
page.

What wasn't handled, was the splice code that actually called a function to
return the length of the data in order to zero out the rest of the page
before sending it up to user space. These data bits were returned with the
length making the value negative, and that negative value was not checked.
It was compared to PAGE_SIZE, and only used if the size was less than
PAGE_SIZE. Luckily PAGE_SIZE is unsigned long which made the compare an
unsigned compare, meaning the negative size value did not end up causing a
large portion of memory to be randomly zeroed out.

Fixes: 66a8cb95ed ("ring-buffer: Add place holder recording of dropped events")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-02 20:31:03 +01:00
..
blktrace.c blktrace: Fix potential deadlock between delete & sysfs ops 2017-09-25 08:56:05 -06:00
bpf_trace.c bpf: fix corruption on concurrent perf_event_output calls 2017-12-25 14:26:31 +01:00
ftrace.c ftrace: Fix kmemleak in unregister_ftrace_graph 2017-10-03 10:27:32 -04:00
Kconfig tracing: Rename update the enum_map file 2017-06-13 17:13:06 -04:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
power-traces.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ring_buffer.c ring-buffer: Mask out the info bits when returning buffer page length 2018-01-02 20:31:03 +01:00
ring_buffer_benchmark.c ring-buffer: Have ring_buffer_alloc_read_page() return error on offline CPU 2017-08-02 14:23:02 -04:00
rpm-traces.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace.c tracing: Fix crash when it fails to alloc ring buffer 2018-01-02 20:30:55 +01:00
trace.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_benchmark.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_benchmark.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_branch.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_clock.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/clock.h> 2017-03-02 08:42:27 +01:00
trace_entries.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_event_perf.c perf/ftrace: Fix double traces of perf on ftrace:function 2017-08-29 13:29:29 +02:00
trace_events.c tracing: Fix clear of RECORDED_TGID flag when disabling trace event 2017-09-05 12:00:09 -04:00
trace_events_filter.c mm: treewide: remove GFP_TEMPORARY allocation flag 2017-09-13 18:53:16 -07:00
trace_events_filter_test.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_events_hist.c tracing: Exclude 'generic fields' from histograms 2017-12-25 14:26:27 +01:00
trace_events_trigger.c sched/headers: Prepare to use <linux/rcuupdate.h> instead of <linux/rculist.h> in <linux/sched.h> 2017-03-02 08:42:38 +01:00
trace_export.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_functions.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_functions_graph.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_hwlat.c trace: make trace_hwlat timestamp y2038 safe 2017-05-08 17:15:15 -07:00
trace_irqsoff.c clocksource: Use a plain u64 instead of cycle_t 2016-12-25 11:04:12 +01:00
trace_kdb.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_kprobe.c perf/ftrace: Fix double traces of perf on ftrace:function 2017-08-29 13:29:29 +02:00
trace_mmiotrace.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_nop.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_output.c sched/tracing: Use common task-state helpers 2017-09-29 11:02:45 +02:00
trace_output.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_printk.c tracing: Handle NULL formats in hold_module_trace_bprintk_format() 2016-06-20 09:46:12 -04:00
trace_probe.c tracing/probes: Fix a warning message to show correct maximum length 2017-02-15 10:32:48 -05:00
trace_probe.h perf/core: Rename CONFIG_[UK]PROBE_EVENT to CONFIG_[UK]PROBE_EVENTS 2017-03-01 10:26:39 +01:00
trace_sched_switch.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_sched_wakeup.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_selftest.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_selftest_dynamic.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_seq.c tracing: use %*pb[l] to print bitmaps including cpumasks and nodemasks 2015-02-13 21:21:37 -08:00
trace_stack.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_stat.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_stat.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_syscalls.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_uprobe.c perf/ftrace: Fix double traces of perf on ftrace:function 2017-08-29 13:29:29 +02:00
tracing_map.c tracing: Fix kmemleak in tracing_map_array_free() 2017-08-24 10:05:51 -04:00
tracing_map.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00