[PATCH] tracing: Fix mmiotrace possible NULL dereferencing of hiter->dev
Steven Rostedt <[email protected]>
| Newsgroups | org.kernel.vger.linux-trace-kernel,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
From: Steven Rostedt <[email protected]> If the mmio_pipe_open() fails to find a PCI device, the hiter->dev will be assigned to NULL. The mmiotrace read() function dereferences the hiter->dev if hiter exists. Change the test of the read to not only check hiter being NULL, but also the hiter->dev before dereferencing it. Cc: [email protected] Fixes: f984b51e0779 ("ftrace: add mmiotrace plugin") Reported-by: Sashiko Link: https://sashiko.dev/#/patchset/20260715143604.14481-1-gaikwad.dcg%40gmail.com Signed-off-by: Steven Rostedt <[email protected]> --- kernel/trace/trace_mmiotrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c index 20812e7f911f..b88b8d9923ad 100644 --- a/kernel/trace/trace_mmiotrace.c +++ b/kernel/trace/trace_mmiotrace.c @@ -145,7 +145,7 @@ static ssize_t mmio_read(struct trace_iterator *iter, struct file *filp, goto print_out; } - if (!hiter) + if (!hiter || !hiter->dev) return 0; mmio_print_pcidev(s, hiter->dev); -- 2.53.0