From 836b2fe544a5e9b5ce116622cb36fba33838c6fd Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 4 Sep 2026 01:33:23 -0700 Subject: selftests/bpf: Check that JMP32 pointer vs zero jumps are not predicted Add jmp32_ptr_vs_zero_jne: the fall-through of the 32-bit compare, which the verifier used to skip, contains an out of bounds map value access, hence w/o the previous patch the program is accepted. See previous patch for detailed description. Reported-by: Nicholas Carlini Suggested-by: Nicholas Carlini Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/bpf/20260904083325.2083493-6-eddyz87@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- lib/memory-notifier-error-inject.c | 49 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 lib/memory-notifier-error-inject.c (limited to 'lib/memory-notifier-error-inject.c') diff --git a/lib/memory-notifier-error-inject.c b/lib/memory-notifier-error-inject.c new file mode 100644 index 000000000..2c46dde59 --- /dev/null +++ b/lib/memory-notifier-error-inject.c @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include +#include + +#include "notifier-error-inject.h" + +static int priority; +module_param(priority, int, 0); +MODULE_PARM_DESC(priority, "specify memory notifier priority"); + +static struct notifier_err_inject memory_notifier_err_inject = { + .actions = { + { NOTIFIER_ERR_INJECT_ACTION(MEM_GOING_ONLINE) }, + { NOTIFIER_ERR_INJECT_ACTION(MEM_GOING_OFFLINE) }, + {} + } +}; + +static struct dentry *dir; + +static int err_inject_init(void) +{ + int err; + + dir = notifier_err_inject_init("memory", notifier_err_inject_dir, + &memory_notifier_err_inject, priority); + if (IS_ERR(dir)) + return PTR_ERR(dir); + + err = register_memory_notifier(&memory_notifier_err_inject.nb); + if (err) + debugfs_remove_recursive(dir); + + return err; +} + +static void err_inject_exit(void) +{ + unregister_memory_notifier(&memory_notifier_err_inject.nb); + debugfs_remove_recursive(dir); +} + +module_init(err_inject_init); +module_exit(err_inject_exit); + +MODULE_DESCRIPTION("memory notifier error injection module"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Akinobu Mita "); -- cgit v1.3.1