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/testing/selftests/tmpfs/.gitignore | 2 + tools/testing/selftests/tmpfs/Makefile | 7 ++ tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c | 78 ++++++++++++++++++++++ 3 files changed, 87 insertions(+) create mode 100644 tools/testing/selftests/tmpfs/.gitignore create mode 100644 tools/testing/selftests/tmpfs/Makefile create mode 100644 tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c (limited to 'tools/testing/selftests/tmpfs') diff --git a/tools/testing/selftests/tmpfs/.gitignore b/tools/testing/selftests/tmpfs/.gitignore new file mode 100644 index 000000000..b1afaa925 --- /dev/null +++ b/tools/testing/selftests/tmpfs/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +/bug-link-o-tmpfile diff --git a/tools/testing/selftests/tmpfs/Makefile b/tools/testing/selftests/tmpfs/Makefile new file mode 100644 index 000000000..3be931e11 --- /dev/null +++ b/tools/testing/selftests/tmpfs/Makefile @@ -0,0 +1,7 @@ +# SPDX-License-Identifier: GPL-2.0-only +CFLAGS += -Wall -O2 + +TEST_GEN_PROGS := +TEST_GEN_PROGS += bug-link-o-tmpfile + +include ../lib.mk diff --git a/tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c b/tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c new file mode 100644 index 000000000..5cb4e404a --- /dev/null +++ b/tools/testing/selftests/tmpfs/bug-link-o-tmpfile.c @@ -0,0 +1,78 @@ +/* + * Copyright (c) 2019 Alexey Dobriyan + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +/* Test that open(O_TMPFILE), linkat() doesn't screw accounting. */ +#include +#include +#include +#include +#include +#include +#include +#include + +#include "kselftest.h" + +int main(void) +{ + int fd; + + // Setting up kselftest framework + ksft_print_header(); + ksft_set_plan(1); + + // Check if test is run as root + if (geteuid()) { + ksft_exit_skip("This test needs root to run!\n"); + return 1; + } + + if (unshare(CLONE_NEWNS) == -1) { + if (errno == ENOSYS || errno == EPERM) { + ksft_exit_skip("unshare() error: unshare, errno %d\n", errno); + } else { + ksft_exit_fail_msg("unshare() error: unshare, errno %d\n", errno); + } + } + + if (mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL) == -1) { + ksft_exit_fail_msg("mount() error: Root filesystem private mount: Fail %d\n", errno); + } + + /* Our heroes: 1 root inode, 1 O_TMPFILE inode, 1 permanent inode. */ + if (mount(NULL, "/tmp", "tmpfs", 0, "nr_inodes=3") == -1) { + ksft_exit_fail_msg("mount() error: Mounting tmpfs on /tmp: Fail %d\n", errno); + } + + fd = openat(AT_FDCWD, "/tmp", O_WRONLY|O_TMPFILE, 0600); + if (fd == -1) { + ksft_exit_fail_msg("openat() error: Open first temporary file: Fail %d\n", errno); + } + + if (linkat(fd, "", AT_FDCWD, "/tmp/1", AT_EMPTY_PATH) == -1) { + ksft_exit_fail_msg("linkat() error: Linking the temporary file: Fail %d\n", errno); + /* Ensure fd is closed on failure */ + close(fd); + } + close(fd); + + fd = openat(AT_FDCWD, "/tmp", O_WRONLY|O_TMPFILE, 0600); + if (fd == -1) { + ksft_exit_fail_msg("openat() error: Opening the second temporary file: Fail %d\n", errno); + } + ksft_test_result_pass(" "); + ksft_exit_pass(); + return 0; +} -- cgit v1.3.1