diff mbox series

trace-cmd library: Fix off by one in tracecmd_read_cpu_first()

Message ID 20220314130201.6356821a@gandalf.local.home (mailing list archive)
State Accepted
Commit 99660051e2b55be77dd638e0cce31ce6879cace5
Headers show
Series trace-cmd library: Fix off by one in tracecmd_read_cpu_first() | expand

Commit Message

Steven Rostedt March 14, 2022, 5:02 p.m. UTC 
From: "Steven Rostedt (Google)" <rostedt@goodmis.org>

The check in tracecmd_read_cpu_first() checks:

  if (cpus > handle->cpus)

When that should be >=, as cpus is the number of CPUs in the array, and
not the last CPU.

This wasn't noticed in tests because it only warns and does not crash.

Fixes: 3869d1529a99 ("trace-cmd library: Do not read CPU greater than CPUs registered")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
 lib/trace-cmd/trace-input.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/lib/trace-cmd/trace-input.c b/lib/trace-cmd/trace-input.c
index 313534d09e86..643dd807c575 100644
--- a/lib/trace-cmd/trace-input.c
+++ b/lib/trace-cmd/trace-input.c
@@ -2028,7 +2028,7 @@  tracecmd_read_cpu_first(struct tracecmd_input *handle, int cpu)
 	unsigned long long page_offset;
 	int ret;
 
-	if (cpu > handle->cpus)
+	if (cpu >= handle->cpus)
 		return NULL;
 
 	page_offset = calc_page_offset(handle, handle->cpu_data[cpu].file_offset);