diff options
| author | Dapeng Mi <dapeng1.mi@linux.intel.com> | 2026-06-16 12:46:54 +0800 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2026-06-30 11:46:08 +0200 |
| commit | a4573a3838ae4fc73b70019cfa1dac9aaea7cc2f (patch) | |
| tree | c3c3078ddc2cbb07cbfa5dda3e123d244f09061f | |
| parent | 166f10836a653dfa280d4335603b52f685b8b1ef (diff) | |
| download | linux-a4573a3838ae4fc73b70019cfa1dac9aaea7cc2f.tar.gz linux-a4573a3838ae4fc73b70019cfa1dac9aaea7cc2f.zip | |
perf/core: Check kernel access when kernel callchains are requested
perf_event_open() currently gates perf_allow_kernel() only on
!attr.exclude_kernel.
However, users can still request kernel callchain collection with
attr.exclude_callchain_kernel == 0 even when attr.exclude_kernel == 1.
That still requires kernel profiling privilege, but the existing check
does not enforce it.
Update the permission check to call perf_allow_kernel() when either
kernel sampling is requested or kernel callchains are requested.
This keeps permission checks aligned with requested data and prevents
unprivileged use of kernel callchain capture.
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260616044654.3468742-9-dapeng1.mi@linux.intel.com
| -rw-r--r-- | kernel/events/core.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index dd3bd9cf1986..0f29d17a600d 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -13932,7 +13932,9 @@ SYSCALL_DEFINE5(perf_event_open, if (err) return err; - if (!attr.exclude_kernel) { + if (!attr.exclude_kernel || + ((attr.sample_type & PERF_SAMPLE_CALLCHAIN) && + !attr.exclude_callchain_kernel)) { err = perf_allow_kernel(); if (err) return err; |