From bce7698e2e6565bb765bd0522337f29f5f312624 Mon Sep 17 00:00:00 2001 From: Haojie Li Date: Tue, 25 Aug 2026 18:08:45 +0800 Subject: drm/mediatek: Add missing IS_ERR check for ovl_adaptor platform device platform_device_register_data() can fail and return an ERR_PTR, but the return value is used without checking, leading to an invalid pointer being stored in ddp_comp[].dev and passed to component_match_add() and mtk_ddp_comp_init(), which could result in a kernel crash. Add an IS_ERR() check to jump to the error handling path on failure. Fixes: 0d9eee9118b7 ("drm/mediatek: Add drm ovl_adaptor sub driver for MT8195") Cc: stable@vger.kernel.org Signed-off-by: Haojie Li Reviewed-by: CK Hu Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20260825100845.438893-1-lihaojie@kylinos.cn/ Signed-off-by: Chun-Kuang Hu --- tools/perf/util/fncache.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 tools/perf/util/fncache.c (limited to 'tools/perf/util/fncache.c') diff --git a/tools/perf/util/fncache.c b/tools/perf/util/fncache.c new file mode 100644 index 000000000..bf9559c55 --- /dev/null +++ b/tools/perf/util/fncache.c @@ -0,0 +1,68 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Manage a cache of file names' existence */ +#include +#include +#include +#include +#include +#include "fncache.h" +#include "hashmap.h" + +static struct hashmap *fncache; + +static size_t fncache__hash(long key, void *ctx __maybe_unused) +{ + return str_hash((const char *)key); +} + +static bool fncache__equal(long key1, long key2, void *ctx __maybe_unused) +{ + return strcmp((const char *)key1, (const char *)key2) == 0; +} + +static void fncache__init(void) +{ + fncache = hashmap__new(fncache__hash, fncache__equal, /*ctx=*/NULL); +} + +static struct hashmap *fncache__get(void) +{ + static pthread_once_t fncache_once = PTHREAD_ONCE_INIT; + + pthread_once(&fncache_once, fncache__init); + + return fncache; +} + +static bool lookup_fncache(const char *name, bool *res) +{ + long val; + + if (!hashmap__find(fncache__get(), name, &val)) + return false; + + *res = (val != 0); + return true; +} + +static void update_fncache(const char *name, bool res) +{ + char *old_key = NULL, *key = strdup(name); + + if (key) { + hashmap__set(fncache__get(), key, res, &old_key, /*old_value*/NULL); + free(old_key); + } +} + +/* No LRU, only use when bounded in some other way. */ +bool file_available(const char *name) +{ + bool res; + + if (lookup_fncache(name, &res)) + return res; + res = access(name, R_OK) == 0; + update_fncache(name, res); + return res; +} -- cgit v1.3.1