diff options
| author | Steven Rostedt (Red Hat) <rostedt@goodmis.org> | 2014-11-19 16:56:41 +0100 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2014-11-20 04:01:16 +0100 |
| commit | 820b75f63d0152dbb9ff4accf274408592d613f2 (patch) | |
| tree | ffe2dd4764a94f0d84877b45b9a14f59d5e63c93 /kernel/trace | |
| parent | tracing: Use trace_seq_used() and seq_buf_used() instead of len (diff) | |
| download | linux-820b75f63d0152dbb9ff4accf274408592d613f2.tar.xz linux-820b75f63d0152dbb9ff4accf274408592d613f2.zip | |
tracing: Add paranoid size check in trace_printk_seq()
To be really paranoid about writing out of bound data in
trace_printk_seq(), add another check of len compared to size.
Link: http://lkml.kernel.org/r/20141119144004.GB2332@dhcp128.suse.cz
Suggested-by: Petr Mladek <pmladek@suse.cz>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 9023446b2c2b..26facec4625e 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -6656,6 +6656,14 @@ trace_printk_seq(struct trace_seq *s) if (s->seq.len >= TRACE_MAX_PRINT) s->seq.len = TRACE_MAX_PRINT; + /* + * More paranoid code. Although the buffer size is set to + * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just + * an extra layer of protection. + */ + if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) + s->seq.len = s->seq.size - 1; + /* should be zero ended, but we are paranoid. */ s->buffer[s->seq.len] = 0; |