From 33a154a96e71a34a1bcca9f40da343dbbf7b38b4 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 1 Oct 2026 14:52:55 +0000 Subject: selftests/bpf: Test packet range of pointers sharing an id Add tests where two packet pointers share an id and tightening one pointer's umax from its var_off would put it less than their constant distance from the other's umax: with an index & 0x38 capped at 50, the base pointer keeps umax 50, so the pointer 8 bytes further on must keep umax 58, even though its known bits allow at most 56. These refused a valid program or accepted an out-of-bounds access before the fix: - check the advanced copy, load through the base: valid, was refused; - check the base, load the byte at base + 1 through a copy advanced by 8: was accepted; - check base + 4, load 4 bytes at base + 2 through base + 8: reads two bytes past the checked range, was accepted; - the same as the second with data_meta pointers checked against data: was accepted. These pass with and without the fix and cover nearby paths: - subtract an unknown scalar from a checked pointer and load below it (the range is kept across a new id); - reach a load through two paths whose checks cover 8 and 7 bytes after the loaded pointer; the second path must not be pruned by the first; - spill a copy of a pointer, check the pointer, fill the copy and load one byte past the checked range: the load is refused, and the copy has the range of the check. Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- drivers/firmware/efi/efibc.c | 92 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) create mode 100644 drivers/firmware/efi/efibc.c (limited to 'drivers/firmware/efi/efibc.c') diff --git a/drivers/firmware/efi/efibc.c b/drivers/firmware/efi/efibc.c new file mode 100644 index 000000000..345a10aa7 --- /dev/null +++ b/drivers/firmware/efi/efibc.c @@ -0,0 +1,92 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * efibc: control EFI bootloaders which obey LoaderEntryOneShot var + * Copyright (c) 2013-2016, Intel Corporation. + */ + +#define pr_fmt(fmt) "efibc: " fmt + +#include +#include +#include +#include +#include + +#define MAX_DATA_LEN 512 + +static int efibc_set_variable(efi_char16_t *name, efi_char16_t *value, + unsigned long len) +{ + efi_status_t status; + + status = efi.set_variable(name, &LINUX_EFI_LOADER_ENTRY_GUID, + EFI_VARIABLE_NON_VOLATILE + | EFI_VARIABLE_BOOTSERVICE_ACCESS + | EFI_VARIABLE_RUNTIME_ACCESS, + len * sizeof(efi_char16_t), value); + + if (status != EFI_SUCCESS) { + pr_err("failed to set EFI variable: 0x%lx\n", status); + return -EIO; + } + return 0; +} + +static int efibc_reboot_notifier_call(struct notifier_block *notifier, + unsigned long event, void *data) +{ + efi_char16_t *reason = event == SYS_RESTART ? L"reboot" + : L"shutdown"; + const u8 *str = data; + efi_char16_t *wdata; + unsigned long l; + int ret; + + ret = efibc_set_variable(L"LoaderEntryRebootReason", reason, + ucs2_strlen(reason)); + if (ret || !data) + return NOTIFY_DONE; + + wdata = kmalloc_objs(efi_char16_t, MAX_DATA_LEN); + if (!wdata) + return NOTIFY_DONE; + + for (l = 0; l < MAX_DATA_LEN - 1 && str[l] != '\0'; l++) + wdata[l] = str[l]; + wdata[l] = L'\0'; + + efibc_set_variable(L"LoaderEntryOneShot", wdata, l); + + kfree(wdata); + return NOTIFY_DONE; +} + +static struct notifier_block efibc_reboot_notifier = { + .notifier_call = efibc_reboot_notifier_call, +}; + +static int __init efibc_init(void) +{ + int ret; + + if (!efi_rt_services_supported(EFI_RT_SUPPORTED_SET_VARIABLE)) + return -ENODEV; + + ret = register_reboot_notifier(&efibc_reboot_notifier); + if (ret) + pr_err("unable to register reboot notifier\n"); + + return ret; +} +module_init(efibc_init); + +static void __exit efibc_exit(void) +{ + unregister_reboot_notifier(&efibc_reboot_notifier); +} +module_exit(efibc_exit); + +MODULE_AUTHOR("Jeremy Compostella "); +MODULE_AUTHOR("Matt Gumbel