bootchart: fix a potential buffer overrun

If the configured number of samples was close to MAXSAMPLES,
the samples buffer could be overrun:

- by 1, because of off-by-one in the condition (samples > arg_samples_len),
and
- by many in case of an overrun, because the number of samples to
  capture was increased, instead of being decreased.

Simplify things by converting to a normal for-loop.

In store.c: change buffer size from 4095 to 4096. 4095 is a strange
number.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/bootchart/store.c b/src/bootchart/store.c
index 343365e612..b2652c8d93 100644
--- a/src/bootchart/store.c
+++ b/src/bootchart/store.c
@@ -114,7 +114,7 @@ static int pid_cmdline_strscpy(char *buffer, size_t buf_len, int pid) {
 void log_sample(int sample) {
         static int vmstat;
         static int schedstat;
-        char buf[4095];
+        char buf[4096];
         char key[256];
         char val[256];
         char rt[256];