Steven Rostedt (VMware) 9dc9648942 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 20:33:22 +01:00
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blktrace.c
bpf_trace.c
ftrace.c	ftrace: Fix kmemleak in unregister_ftrace_graph	2017-10-12 11:27:33 +02:00
Kconfig
Makefile	Makefile: Mute warning for __builtin_return_address(>0) for tracing only	2016-09-30 10:18:35 +02:00
power-traces.c
ring_buffer.c	ring-buffer: Mask out the info bits when returning buffer page length	2018-01-02 20:33:22 +01:00
ring_buffer_benchmark.c
rpm-traces.c
trace.c	tracing: Fix crash when it fails to alloc ring buffer	2018-01-02 20:33:22 +01:00
trace.h
trace_benchmark.c
trace_benchmark.h
trace_branch.c
trace_clock.c
trace_entries.h
trace_event_perf.c
trace_events.c
trace_events_filter.c	tracing: Fix freeing of filter in create_filter() when set_str is false	2017-08-30 10:19:24 +02:00
trace_events_filter_test.h
trace_events_trigger.c
trace_export.c
trace_functions.c
trace_functions_graph.c	fgraph: Handle a case where a tracer ignores set_graph_notrace	2017-01-09 08:07:50 +01:00
trace_irqsoff.c
trace_kdb.c
trace_kprobe.c	tracing/kprobes: Allow to create probe with a module name starting with a digit	2017-07-15 11:57:45 +02:00
trace_mmiotrace.c
trace_nop.c
trace_output.c
trace_output.h
trace_printk.c
trace_probe.c
trace_probe.h
trace_sched_switch.c
trace_sched_wakeup.c
trace_selftest.c	ftrace: Fix selftest goto location on error	2017-09-27 11:00:16 +02:00
trace_selftest_dynamic.c
trace_seq.c
trace_stack.c
trace_stat.c
trace_stat.h
trace_syscalls.c
trace_uprobe.c