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.h | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) create mode 100644 tools/perf/util/rwsem.h (limited to 'tools/perf/util/rwsem.h') diff --git a/tools/perf/util/rwsem.h b/tools/perf/util/rwsem.h new file mode 100644 index 000000000..b102d8143 --- /dev/null +++ b/tools/perf/util/rwsem.h @@ -0,0 +1,30 @@ +#ifndef _PERF_RWSEM_H +#define _PERF_RWSEM_H + +#include +#include "mutex.h" + +/* + * Mutexes have additional error checking. Enable to use a mutex rather than a + * rwlock for debugging. + */ +#define RWS_ERRORCHECK 0 + +struct LOCKABLE rw_semaphore { +#if RWS_ERRORCHECK + struct mutex mtx; +#else + pthread_rwlock_t lock; +#endif +}; + +int init_rwsem(struct rw_semaphore *sem); +int exit_rwsem(struct rw_semaphore *sem); + +int down_read(struct rw_semaphore *sem) SHARED_LOCK_FUNCTION(sem); +int up_read(struct rw_semaphore *sem) UNLOCK_FUNCTION(sem); + +int down_write(struct rw_semaphore *sem) EXCLUSIVE_LOCK_FUNCTION(sem); +int up_write(struct rw_semaphore *sem) UNLOCK_FUNCTION(sem); + +#endif /* _PERF_RWSEM_H */ -- cgit v1.3.1