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authorFan Wu <fanwu01@zju.edu.cn>2026-08-20 13:53:06 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2026-09-01 16:50:04 +0200
commit263f7d61a4201cde16849b2d016251806e7418be (patch)
tree861df7c5b878b85741cf319ece81111b4c41c3b1 /tools/perf/util/cap.c
downloadlinux-stable-263f7d61a4201cde16849b2d016251806e7418be.tar.gz
linux-stable-263f7d61a4201cde16849b2d016251806e7418be.zip
usb: typec: qcom-pmic-typec: disable cc_debounce_dwork on stopgrafted
cc_debounce_dwork is queued from the set_cc() and start_toggling() callbacks, which run from TCPM's kthread worker. port_stop() returns before tcpm_unregister_port() destroys that worker. Flushing the worker during unregister may therefore run a callback which queues the delayed work after port_stop() has returned. The delayed work can then run after devres has freed pmic_typec_port. Use disable_delayed_work_sync() in port_stop() to cancel a pending instance and prevent the TCPM callbacks from queueing another one. This issue was found by an in-house static analysis tool. Fixes: a4422ff22142 ("usb: typec: qcom: Add Qualcomm PMIC Type-C driver") Cc: stable <stable@kernel.org> # v6.10+ Assisted-by: Codex:gpt-5.6 Signed-off-by: Fan Wu <fanwu01@zju.edu.cn> Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Link: https://patch.msgid.link/20260820135307.153773-2-fanwu01@zju.edu.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'tools/perf/util/cap.c')
-rw-r--r--tools/perf/util/cap.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/tools/perf/util/cap.c b/tools/perf/util/cap.c
new file mode 100644
index 000000000..272bd8255
--- /dev/null
+++ b/tools/perf/util/cap.c
@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Capability utilities
+ */
+
+#include "cap.h"
+#include "debug.h"
+#include <errno.h>
+#include <string.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+
+#define MAX_LINUX_CAPABILITY_U32S _LINUX_CAPABILITY_U32S_3
+
+bool perf_cap__capable(int cap)
+{
+ struct __user_cap_header_struct header = {
+ .version = _LINUX_CAPABILITY_VERSION_3,
+ .pid = 0,
+ };
+ struct __user_cap_data_struct data[MAX_LINUX_CAPABILITY_U32S] = {};
+ __u32 cap_val;
+
+ while (syscall(SYS_capget, &header, &data[0]) == -1) {
+ /* Retry, first attempt has set the header.version correctly. */
+ if (errno == EINVAL && header.version != _LINUX_CAPABILITY_VERSION_3 &&
+ header.version == _LINUX_CAPABILITY_VERSION_1)
+ continue;
+
+ pr_debug2("capget syscall failed (%m) fall back on root check\n");
+ return geteuid() == 0;
+ }
+
+ /* Extract the relevant capability bit. */
+ if (cap >= 32) {
+ if (header.version == _LINUX_CAPABILITY_VERSION_3) {
+ cap_val = data[1].effective;
+ } else {
+ /* Capability beyond 32 is requested but only 32 are supported. */
+ return false;
+ }
+ } else {
+ cap_val = data[0].effective;
+ }
+ return (cap_val & (1 << (cap & 0x1f))) != 0;
+}