From 85f726a35e504418607b77c5e7da165dc1ea63ce Mon Sep 17 00:00:00 2001 From: Tom Zanussi Date: Tue, 5 Mar 2019 10:12:00 -0600 Subject: tracing: Use strncpy instead of memcpy when copying comm in trace.c Because there may be random garbage beyond a string's null terminator, code that might use the entire comm array e.g. histogram keys, can give unexpected results if that garbage is copied in too, so avoid that possibility by using strncpy instead of memcpy. Link: http://lkml.kernel.org/r/1d6ebac26570c2a29ce9fb575379f17ef5c8b81b.1551802084.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi Suggested-by: Steven Rostedt (VMware) Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 3835f7ed3293..e9cc47e59d25 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1497,7 +1497,7 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) max_data->critical_start = data->critical_start; max_data->critical_end = data->critical_end; - memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); + strncpy(max_data->comm, tsk->comm, TASK_COMM_LEN); max_data->pid = tsk->pid; /* * If tsk == current, then use current_uid(), as that does not use @@ -1923,7 +1923,7 @@ static inline char *get_saved_cmdlines(int idx) static inline void set_cmdline(int idx, const char *cmdline) { - memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); + strncpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); } static int allocate_cmdlines_buffer(unsigned int val, -- cgit v1.2.3