diff options
| author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2019-10-11 17:22:50 -0400 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2019-10-12 20:48:06 -0400 |
| commit | 17911ff38aa58d3c95c07589dbf5d3564c4cf3c5 (patch) | |
| tree | 0437649533f3c50b4207fd9368bf47ae06bcfe95 /kernel/trace/trace_events_hist.c | |
| parent | 8530dec63e7b486e3761cc3d74a22de301845ff5 (diff) | |
tracing: Add locked_down checks to the open calls of files created for tracefs
Added various checks on open tracefs calls to see if tracefs is in lockdown
mode, and if so, to return -EPERM.
Note, the event format files (which are basically standard on all machines)
as well as the enabled_functions file (which shows what is currently being
traced) are not lockde down. Perhaps they should be, but it seems counter
intuitive to lockdown information to help you know if the system has been
modified.
Link: http://lkml.kernel.org/r/CAHk-=wj7fGPKUspr579Cii-w_y60PtRaiDgKuxVtBAMK0VNNkA@mail.gmail.com
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace_events_hist.c')
| -rw-r--r-- | kernel/trace/trace_events_hist.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index dd18d76bf1bd..57648c5aa679 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -7,6 +7,7 @@ #include <linux/module.h> #include <linux/kallsyms.h> +#include <linux/security.h> #include <linux/mutex.h> #include <linux/slab.h> #include <linux/stacktrace.h> @@ -1448,6 +1449,10 @@ static int synth_events_open(struct inode *inode, struct file *file) { int ret; + ret = security_locked_down(LOCKDOWN_TRACEFS); + if (ret) + return ret; + if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { ret = dyn_events_release_all(&synth_event_ops); if (ret < 0) @@ -5515,6 +5520,12 @@ static int hist_show(struct seq_file *m, void *v) static int event_hist_open(struct inode *inode, struct file *file) { + int ret; + + ret = security_locked_down(LOCKDOWN_TRACEFS); + if (ret) + return ret; + return single_open(file, hist_show, file); } |