linux-brain/kernel/trace
Steven Rostedt (VMware) a0997a86f5 tracing: Check length before giving out the filter buffer
commit b220c049d5196dd94d992dd2dc8cba1a5e6123bf upstream.

When filters are used by trace events, a page is allocated on each CPU and
used to copy the trace event fields to this page before writing to the ring
buffer. The reason to use the filter and not write directly into the ring
buffer is because a filter may discard the event and there's more overhead
on discarding from the ring buffer than the extra copy.

The problem here is that there is no check against the size being allocated
when using this page. If an event asks for more than a page size while being
filtered, it will get only a page, leading to the caller writing more that
what was allocated.

Check the length of the request, and if it is more than PAGE_SIZE minus the
header default back to allocating from the ring buffer directly. The ring
buffer may reject the event if its too big anyway, but it wont overflow.

Link: https://lore.kernel.org/ath10k/1612839593-2308-1-git-send-email-wgong@codeaurora.org/

Cc: stable@vger.kernel.org
Fixes: 0fc1b09ff1 ("tracing: Use temp buffer when filtering events")
Reported-by: Wen Gong <wgong@codeaurora.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-17 10:35:14 +01:00
..
Kconfig tracing/kprobes: Do the notrace functions check without kprobes on ftrace 2021-01-19 18:26:12 +01:00
Makefile tracing: Add unified dynamic event framework 2018-12-08 20:54:09 -05:00
blktrace.c blktrace: ensure our debugfs dir exists 2020-09-03 11:26:42 +02:00
bpf_trace.c bpf: Fix bpf_put_raw_tracepoint()'s use of __module_address() 2020-12-30 11:51:18 +01:00
fgraph.c fgraph: Initialize tracing_graph_pause at task creation 2021-02-10 09:25:29 +01:00
ftrace.c ftrace: Fix updating FTRACE_FL_TRAMP 2020-12-11 13:23:29 +01:00
ftrace_internal.h treewide: Rename rcu_dereference_raw_notrace() to _check() 2019-08-01 14:16:21 -07:00
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
preemptirq_delay_test.c tracing: Use trace_clock_local() for looping in preemptirq_delay_test.c 2018-10-17 15:35:33 -04:00
ring_buffer.c tracing: Fix race in trace_open and buffer resize call 2021-01-30 13:54:10 +01:00
ring_buffer_benchmark.c tracing: Use CONFIG_PREEMPTION 2019-07-31 19:03:35 +02:00
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: Check length before giving out the filter buffer 2021-02-17 10:35:14 +01:00
trace.h ftrace: Handle tracing when switching between context 2020-11-10 12:37:28 +01:00
trace_benchmark.c rcu: Rename cond_resched_rcu_qs() to cond_resched_tasks_rcu_qs() 2018-05-15 10:27:29 -07:00
trace_benchmark.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00
trace_branch.c x86/uaccess, ftrace: Fix ftrace_likely_update() vs. SMAP 2019-04-03 11:02:24 +02:00
trace_clock.c tracing: Add SPDX License format tags to tracing files 2018-08-16 19:08:06 -04:00
trace_dynevent.c tracing: Add tracing_check_open_get_tr() 2019-10-12 20:44:07 -04:00
trace_dynevent.h tracing/dynevent: Pass extra arguments to match operation 2019-08-31 12:19:38 -04:00
trace_entries.h tracing: Set kernel_stack's caller size properly 2020-10-01 13:17:29 +02:00
trace_event_perf.c tracing: Fix race in perf_trace_buf initialization 2019-10-21 19:38:28 -04:00
trace_events.c tracing: Do not count ftrace events in top level enable output 2021-02-17 10:35:14 +01:00
trace_events_filter.c tracing: Avoid memory leak in process_system_preds() 2020-01-09 10:20:00 +01:00
trace_events_filter_test.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00
trace_events_hist.c tracing: fix double free 2020-10-01 13:18:23 +02:00
trace_events_trigger.c tracing: Fix event trigger to accept redundant spaces 2020-06-30 15:37:10 -04:00
trace_export.c tracing: Add trigger file for trace_markers tracefs/ftrace/print 2018-05-29 08:28:53 -04:00
trace_functions.c tracing: Update stack trace skipping for ORC unwinder 2018-01-23 15:57:00 -05:00
trace_functions_graph.c fgraph: Remove redundant ftrace_graph_notrace_addr() test 2019-07-30 21:50:03 -04:00
trace_hwlat.c tracing: Remove WARN_ON in start_thread() 2020-12-08 10:40:28 +01:00
trace_irqsoff.c The biggest change for this release is in the histogram code. 2019-03-11 17:01:32 -07:00
trace_kdb.c tracing: Silence GCC 9 array bounds warning 2019-05-25 23:04:30 -04:00
trace_kprobe.c tracing/kprobe: Fix to support kretprobe events on unloaded modules 2021-02-13 13:52:54 +01:00
trace_kprobe_selftest.c selftest/ftrace: Move kprobe selftest function to separate compile unit 2018-07-30 18:41:04 -04:00
trace_kprobe_selftest.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00
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 tracing: Make the space reserved for the pid wider 2020-10-07 08:01:27 +02:00
trace_output.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00
trace_preemptirq.c lockdep: fix order in trace_hardirqs_off_caller() 2020-10-01 13:18:14 +02:00
trace_printk.c tracing: Add locked_down checks to the open calls of files created for tracefs 2019-10-12 20:48:06 -04:00
trace_probe.c tracing/probe: Fix memleak in fetch_op_data operations 2020-06-24 17:50:51 +02:00
trace_probe.h tracing/uprobe: Fix to make trace_uprobe_filter alignment safe 2020-02-05 21:22:53 +00:00
trace_probe_tmpl.h tracing/probe: Support user-space dereference 2019-05-25 23:04:42 -04:00
trace_sched_switch.c tracing: Fix sched switch start/stop refcount racy updates 2020-02-11 04:35:07 -08:00
trace_sched_wakeup.c kernel/trace: Fix do not unregister tracepoints when register sched_migrate_task fail 2020-01-14 20:08:22 +01:00
trace_selftest.c ftrace: Handle tracing when switching between context 2020-11-10 12:37:28 +01:00
trace_selftest_dynamic.c ftrace: Mark function tracer test functions noinline/noclone 2018-01-23 15:57:29 -05:00
trace_seq.c tracing: Add SPDX License format tags to tracing files 2018-08-16 19:08:06 -04:00
trace_stack.c tracing: Have stack tracer compile when MCOUNT_INSN_SIZE is not defined 2020-01-14 20:08:22 +01:00
trace_stat.c tracing: Fix very unlikely race of registering two stat tracers 2020-02-24 08:36:30 +01:00
trace_stat.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00
trace_syscalls.c syscalls: Remove start and number from syscall_get_arguments() args 2019-04-05 09:26:43 -04:00
trace_uprobe.c tracing/probe: Fix bpf_task_fd_query() for kprobes and uprobes 2020-06-24 17:50:43 +02:00
tracing_map.c tracing: Have the histogram compare functions convert to u64 first 2020-01-09 10:20:00 +01:00
tracing_map.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00