user/sven/linux.git/kernel/livepatch, branch v5.18.3

Merge tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2022-03-29T00:29:53Z

Pull ptrace cleanups from Eric Biederman: "This set of changes removes tracehook.h, moves modification of all of the ptrace fields inside of siglock to remove races, adds a missing permission check to ptrace.c The removal of tracehook.h is quite significant as it has been a major source of confusion in recent years. Much of that confusion was around task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled making the semantics clearer). For people who don't know tracehook.h is a vestiage of an attempt to implement uprobes like functionality that was never fully merged, and was later superseeded by uprobes when uprobes was merged. For many years now we have been removing what tracehook functionaly a little bit at a time. To the point where anything left in tracehook.h was some weird strange thing that was difficult to understand" * tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: ptrace: Remove duplicated include in ptrace.c ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE ptrace: Return the signal to continue with from ptrace_stop ptrace: Move setting/clearing ptrace_message into ptrace_stop tracehook: Remove tracehook.h resume_user_mode: Move to resume_user_mode.h resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume signal: Move set_notify_signal and clear_notify_signal into sched/signal.h task_work: Decouple TIF_NOTIFY_SIGNAL and task_work task_work: Call tracehook_notify_signal from get_signal on all architectures task_work: Introduce task_work_pending task_work: Remove unnecessary include from posix_timers.h ptrace: Remove tracehook_signal_handler ptrace: Remove arch_syscall_{enter,exit}_tracehook ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h ptrace/arm: Rename tracehook_report_syscall report_syscall ptrace: Move ptrace_report_syscall into ptrace.h

Merge tag 'livepatching-for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching

2022-03-28T21:38:31Z

Pull livepatching updates from Petr Mladek: - Forced transitions block only to-be-removed livepatches [Chengming] - Detect when ftrace handler could not be disabled in self-tests [David] - Calm down warning from a static analyzer [Tom] * tag 'livepatching-for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching: livepatch: Reorder to use before freeing a pointer livepatch: Don't block removal of patches that are safe to unload livepatch: Skip livepatch tests if ftrace cannot be configured

Merge tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2022-03-27T17:17:23Z

Pull x86 CET-IBT (Control-Flow-Integrity) support from Peter Zijlstra: "Add support for Intel CET-IBT, available since Tigerlake (11th gen), which is a coarse grained, hardware based, forward edge Control-Flow-Integrity mechanism where any indirect CALL/JMP must target an ENDBR instruction or suffer #CP. Additionally, since Alderlake (12th gen)/Sapphire-Rapids, speculation is limited to 2 instructions (and typically fewer) on branch targets not starting with ENDBR. CET-IBT also limits speculation of the next sequential instruction after the indirect CALL/JMP [1]. CET-IBT is fundamentally incompatible with retpolines, but provides, as described above, speculation limits itself" [1] https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/branch-history-injection.html * tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits) kvm/emulate: Fix SETcc emulation for ENDBR x86/Kconfig: Only allow CONFIG_X86_KERNEL_IBT with ld.lld >= 14.0.0 x86/Kconfig: Only enable CONFIG_CC_HAS_IBT for clang >= 14.0.0 kbuild: Fixup the IBT kbuild changes x86/Kconfig: Do not allow CONFIG_X86_X32_ABI=y with llvm-objcopy x86: Remove toolchain check for X32 ABI capability x86/alternative: Use .ibt_endbr_seal to seal indirect calls objtool: Find unused ENDBR instructions objtool: Validate IBT assumptions objtool: Add IBT/ENDBR decoding objtool: Read the NOENDBR annotation x86: Annotate idtentry_df() x86,objtool: Move the ASM_REACHABLE annotation to objtool.h x86: Annotate call_on_stack() objtool: Rework ASM_REACHABLE x86: Mark __invalid_creds() __noreturn exit: Mark do_group_exit() __noreturn x86: Mark stop_this_cpu() __noreturn objtool: Ignore extra-symbol code objtool: Rename --duplicate to --lto ...

livepatch: Don't block removal of patches that are safe to unload

2022-03-17T18:02:30Z

module_put() is not called for a patch with "forced" flag. It should block the removal of the livepatch module when the code might still be in use after forced transition. klp_force_transition() currently sets "forced" flag for all patches on the list. In fact, any patch can be safely unloaded when it passed through the consistency model in KLP_UNPATCHED transition. In other words, the "forced" flag must be set only for livepatches that are being removed. In particular, set the "forced" flag: + only for klp_transition_patch when the transition to KLP_UNPATCHED state was forced. + all replaced patches when the transition to KLP_PATCHED state was forced and the patch was replacing the existing patches. Signed-off-by: Chengming Zhou Acked-by: Joe Lawrence Reviewed-by: Petr Mladek Tested-by: Petr Mladek [mbenes@suse.cz: wording improvements] Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220312152220.88127-1-zhouchengming@bytedance.com

x86/livepatch: Validate fentry location

2022-03-15T09:32:37Z

Currently livepatch assumes __fentry__ lives at func+0, which is most likely untrue with IBT on. Instead make it use ftrace_location() by default which both validates and finds the actual ip if there is any in the same symbol. Suggested-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20220308154318.285971256@infradead.org

tracehook: Remove tracehook.h

2022-03-10T22:51:51Z

Now that all of the definitions have moved out of tracehook.h into ptrace.h, sched/signal.h, resume_user_mode.h there is nothing left in tracehook.h so remove it. Update the few files that were depending upon tracehook.h to bring in definitions to use the headers they need directly. Reviewed-by: Kees Cook Link: https://lkml.kernel.org/r/20220309162454.123006-13-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman"

livepatch: Fix build failure on 32 bits processors

2022-02-07T10:03:10Z

Trying to build livepatch on powerpc/32 results in: kernel/livepatch/core.c: In function 'klp_resolve_symbols': kernel/livepatch/core.c:221:23: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 221 | sym = (Elf64_Sym *)sechdrs[symndx].sh_addr + ELF_R_SYM(relas[i].r_info); | ^ kernel/livepatch/core.c:221:21: error: assignment to 'Elf32_Sym *' {aka 'struct elf32_sym *'} from incompatible pointer type 'Elf64_Sym *' {aka 'struct elf64_sym *'} [-Werror=incompatible-pointer-types] 221 | sym = (Elf64_Sym *)sechdrs[symndx].sh_addr + ELF_R_SYM(relas[i].r_info); | ^ kernel/livepatch/core.c: In function 'klp_apply_section_relocs': kernel/livepatch/core.c:312:35: error: passing argument 1 of 'klp_resolve_symbols' from incompatible pointer type [-Werror=incompatible-pointer-types] 312 | ret = klp_resolve_symbols(sechdrs, strtab, symndx, sec, sec_objname); | ^~~~~~~ | | | Elf32_Shdr * {aka struct elf32_shdr *} kernel/livepatch/core.c:193:44: note: expected 'Elf64_Shdr *' {aka 'struct elf64_shdr *'} but argument is of type 'Elf32_Shdr *' {aka 'struct elf32_shdr *'} 193 | static int klp_resolve_symbols(Elf64_Shdr *sechdrs, const char *strtab, | ~~~~~~~~~~~~^~~~~~~ Fix it by using the right types instead of forcing 64 bits types. Fixes: 7c8e2bdd5f0d ("livepatch: Apply vmlinux-specific KLP relocations early") Signed-off-by: Christophe Leroy Acked-by: Petr Mladek Acked-by: Joe Lawrence Acked-by: Miroslav Benes Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/5288e11b018a762ea3351cc8fb2d4f15093a4457.1640017960.git.christophe.leroy@csgroup.eu

Merge tag 'livepatching-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching

2022-01-16T08:08:13Z

Pull livepatching updates from Petr Mladek: - Correctly handle kobjects when a livepatch init fails - Avoid CPU hogging when searching for many livepatched symbols - Add livepatch API page into documentation * tag 'livepatching-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching: livepatch: Avoid CPU hogging with cond_resched livepatch: Fix missing unlock on error in klp_enable_patch() livepatch: Fix kobject refcount bug on klp_init_patch_early failure path Documentation: livepatch: Add livepatch API page

livepatch: Fix missing unlock on error in klp_enable_patch()

2022-01-04T12:57:19Z

Add missing unlock when try_module_get() fails in klp_enable_patch(). Fixes: 5ef3dd20555e8e8 ("livepatch: Fix kobject refcount bug on klp_init_patch_early failure path") Reported-by: Hulk Robot Signed-off-by: Yang Yingliang Acked-by: David Vernet Reviewed-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20211225025115.475348-1-yangyingliang@huawei.com

livepatch: Fix kobject refcount bug on klp_init_patch_early failure path

2022-01-04T12:54:24Z

When enabling a klp patch with klp_enable_patch(), klp_init_patch_early() is invoked to initialize the kobjects for the patch itself, as well as the 'struct klp_object' and 'struct klp_func' objects that comprise it. However, there are some error paths in klp_enable_patch() where some kobjects may have been initialized with kobject_init(), but an error code is still returned due to e.g. a 'struct klp_object' having a NULL funcs pointer. In these paths, the initial reference of the kobject of the 'struct klp_patch' may never be released, along with one or more of its objects and their functions, as kobject_put() is not invoked on the cleanup path if klp_init_patch_early() returns an error code. For example, if an object entry such as the following were added to the sample livepatch module's klp patch, it would cause the vmlinux klp_object, and its klp_func which updates 'cmdline_proc_show', to never be released: static struct klp_object objs[] = { { /* name being NULL means vmlinux */ .funcs = funcs, }, { /* NULL funcs -- would cause reference leak */ .name = "kvm", }, { } }; Without this change, if CONFIG_DEBUG_KOBJECT is enabled, and the sample klp patch is loaded, the kobjects (the patch, the vmlinux 'struct klp_object', and its func) are observed as initialized, but never released, in the dmesg log output. With the change, these kobject references no longer fail to be released as the error case is properly handled before they are initialized. Signed-off-by: David Vernet Reviewed-by: Petr Mladek Acked-by: Miroslav Benes Acked-by: Josh Poimboeuf Signed-off-by: Petr Mladek