tracing: Fixes for v6.17

tracing fixes for v6.17

- Fix buffer overflow in osnoise_cpu_write()

The allocated buffer to read user space did not add a nul terminating byte after copying from user the string. It then reads the string, and if user space did not add a nul byte, the read will continue beyond the string. Add a nul terminating byte after reading the string.

- Fix missing check for lockdown on tracing

There's a path from kprobe events or uprobe events that can update the tracing system even if lockdown on tracing is activate. Add a check in the dynamic event path.

- Add a recursion check for the function graph return path

Now that fprobes can hook to the function graph tracer and call different code between the entry and the exit, the exit code may now call functions that are not called in entry. This means that the exit handler can possibly trigger recursion that is not caught and cause the system to crash. Add the same recursion checks in the function exit handler as exists in the entry handler path.

git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git
trace/fixes

Head SHA1: 0db0934e7f9bb624ed98a665890dbe249f65b8fd

Masami Hiramatsu (Google) (2):
tracing: dynevent: Add a missing lockdown check on dynevent
tracing: fgraph: Protect return handler from recursion loop

Wang Liang (1):
tracing/osnoise: Fix slab-out-of-bounds in _parse_integer_limit()

----

 kernel/trace/fgraph.c         | 12 ++++++++++++
 kernel/trace/trace_dynevent.c |  4 ++++
 kernel/trace/trace_osnoise.c  |  3 ++-
 3 files changed, 18 insertions(+), 1 deletion(-)