[PATCH 0/2] tracing: Fix NULL pointer bug in hist key expressions

[Tom Zanussi]

From: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx>

Hi Steve,

This is a fix for a user-reported bug in the hist triggers, where if a
variable reference is used in an expression in a histogram key, it
results in a NULL pointer dereference and subsequent Oops.

I separated the fix into two small patches, the first preventing the
immediate problem bu disallowing a var_ref from ever accessing a NULL
element, and the second disallowing a user from ever constructing such
a key.

Thanks,

Tom

The following changes since commit ee474b81fe5aa5dc0faae920bf66240fbf55f891:

  tracing/kprobes: Fix strpbrk() argument order (2018-11-05 09:47:14 -0500)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/zanussi/linux-trace.git ftrace/key-ref-fix

Tom Zanussi (2):
  tracing: Prevent hist_field_var_ref() from accessing NULL
    tracing_map_elts
  tracing: Check keys for variable references in expressions too

 kernel/trace/trace_events_hist.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

-- 
2.14.1