[PATCH 5.10] static_call: Replace pointless WARN_ON() in static_call_module_notify() - Linux-stable-mirror

26 Jan 2025

From: Thomas Gleixner tglx@linutronix.de
commit fe513c2ef0a172a58f158e2e70465c4317f0a9a2 upstream.
static_call_module_notify() triggers a WARN_ON(), when memory allocation
fails in __static_call_add_module().
That's not really justified, because the failure case must be correctly
handled by the well known call chain and the error code is passed
through to the initiating userspace application.
A memory allocation fail is not a fatal problem, but the WARN_ON() takes
the machine out when panic_on_warn is set.
Replace it with a pr_warn().
Fixes: 9183c3f9ed71 ("static_call: Add inline static call infrastructure")
Signed-off-by: Thomas Gleixner tglx@linutronix.de
Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org
Link: https://lkml.kernel.org/r/8734mf7pmb.ffs@tglx
Signed-off-by: Alexey Nepomnyashih sdl@nppct.ru
---
Backport to fix CVE-2024-49954
Link: https://nvd.nist.gov/vuln/detail/CVE-2024-49954
---
 kernel/static_call.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/static_call.c b/kernel/static_call.c
index e9408409eb46..a008250e2533 100644
--- a/kernel/static_call.c
+++ b/kernel/static_call.c
@@ -431,7 +431,7 @@ static int static_call_module_notify(struct notifier_block *nb,
    case MODULE_STATE_COMING:
    	ret = static_call_add_module(mod);
    	if (ret) {
-			WARN(1, "Failed to allocate memory for static calls");
+			pr_warn("Failed to allocate memory for static calls\n");
    		static_call_del_module(mod);
    	}
    	break;
-- 
2.43.0



    