From 506ada89629ec7059b96ecfb0dc7d33ece0103ca Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 4 Sep 2026 17:05:56 -0700 Subject: bpf: mark a NULL kfunc argument precise check_kfunc_arg() allows bpf_register_is_null() for nullable arguments w/o marking the underlying scalar register precise. Hence a checkpoint created on such a path would prune against arbitrary scalar value. Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)") Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com Signed-off-by: Alexei Starovoitov --- tools/perf/util/rwsem.c | 71 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 71 insertions(+) create mode 100644 tools/perf/util/rwsem.c (limited to 'tools/perf/util/rwsem.c') diff --git a/tools/perf/util/rwsem.c b/tools/perf/util/rwsem.c new file mode 100644 index 000000000..9d2683239 --- /dev/null +++ b/tools/perf/util/rwsem.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "util.h" +#include "rwsem.h" + +#if RWS_ERRORCHECK +#include "mutex.h" +#endif + +int init_rwsem(struct rw_semaphore *sem) +{ +#if RWS_ERRORCHECK + mutex_init(&sem->mtx); + return 0; +#else + return pthread_rwlock_init(&sem->lock, NULL); +#endif +} + +int exit_rwsem(struct rw_semaphore *sem) +{ +#if RWS_ERRORCHECK + mutex_destroy(&sem->mtx); + return 0; +#else + return pthread_rwlock_destroy(&sem->lock); +#endif +} + +int down_read(struct rw_semaphore *sem) + NO_THREAD_SAFETY_ANALYSIS +{ +#if RWS_ERRORCHECK + mutex_lock(&sem->mtx); + return 0; +#else + return perf_singlethreaded ? 0 : pthread_rwlock_rdlock(&sem->lock); +#endif +} + +int up_read(struct rw_semaphore *sem) + NO_THREAD_SAFETY_ANALYSIS +{ +#if RWS_ERRORCHECK + mutex_unlock(&sem->mtx); + return 0; +#else + return perf_singlethreaded ? 0 : pthread_rwlock_unlock(&sem->lock); +#endif +} + +int down_write(struct rw_semaphore *sem) + NO_THREAD_SAFETY_ANALYSIS +{ +#if RWS_ERRORCHECK + mutex_lock(&sem->mtx); + return 0; +#else + return perf_singlethreaded ? 0 : pthread_rwlock_wrlock(&sem->lock); +#endif +} + +int up_write(struct rw_semaphore *sem) + NO_THREAD_SAFETY_ANALYSIS +{ +#if RWS_ERRORCHECK + mutex_unlock(&sem->mtx); + return 0; +#else + return perf_singlethreaded ? 0 : pthread_rwlock_unlock(&sem->lock); +#endif +} -- cgit v1.3.1