From 68fa7eaea39a8eca759550a465b3aa58696656bb Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Wed, 8 Jan 2025 10:04:30 +0100 Subject: [PATCH] module: Extend the preempt disabled section in dereference_symbol_descriptor(). [ Upstream commit a145c848d69f9c6f32008d8319edaa133360dd74 ] dereference_symbol_descriptor() needs to obtain the module pointer belonging to pointer in order to resolve that pointer. The returned mod pointer is obtained under RCU-sched/ preempt_disable() guarantees and needs to be used within this section to ensure that the module is not removed in the meantime. Extend the preempt_disable() section to also cover dereference_module_function_descriptor(). Fixes: 04b8eb7a4ccd9 ("symbol lookup: introduce dereference_symbol_descriptor()") Cc: James E.J. Bottomley Cc: Christophe Leroy Cc: Helge Deller Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Naveen N Rao Cc: Nicholas Piggin Cc: Sergey Senozhatsky Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Reviewed-by: Sergey Senozhatsky Acked-by: Peter Zijlstra (Intel) Signed-off-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20250108090457.512198-2-bigeasy@linutronix.de Signed-off-by: Petr Pavlu Signed-off-by: Sasha Levin --- include/linux/kallsyms.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h index 430f1cefbb9e1..ea2eb5fe83a3c 100644 --- a/include/linux/kallsyms.h +++ b/include/linux/kallsyms.h @@ -63,10 +63,10 @@ static inline void *dereference_symbol_descriptor(void *ptr) preempt_disable(); mod = __module_address((unsigned long)ptr); - preempt_enable(); if (mod) ptr = dereference_module_function_descriptor(mod, ptr); + preempt_enable(); #endif return ptr; }