kernel/linux.git/include/linux/objtool.h, branch v6.18.21

objtool: Validate kCFI calls

2025-08-18T12:23:09+00:00

Validate that all indirect calls adhere to kCFI rules. Notably doing nocfi indirect call to a cfi function is broken. Apparently some Rust 'core' code violates this and explodes when ran with FineIBT. All the ANNOTATE_NOCFI_SYM sites are prime targets for attackers. - runtime EFI is especially henous because it also needs to disable IBT. Basically calling unknown code without CFI protection at runtime is a massice security issue. - Kexec image handover; if you can exploit this, you get to keep it :-) Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Acked-by: Sean Christopherson Link: https://lkml.kernel.org/r/20250714103441.496787279@infradead.org

objtool: Fix up some outdated references to ENTRY/ENDPROC

2025-03-25T08:20:27+00:00

ENTRY and ENDPROC were deprecated years ago and replaced with SYM_FUNC_{START,END}. Fix up a few outdated references in the objtool documentation and comments. Also fix a few typos. Suggested-by: Brendan Jackman Suggested-by: Miroslav Benes Signed-off-by: Josh Poimboeuf Signed-off-by: Ingo Molnar Cc: Linus Torvalds Link: https://lore.kernel.org/r/5eb7e06e1a0e87aaeda8d583ab060e7638a6ea8e.1742852846.git.jpoimboe@kernel.org

x86/boot: Mark start_secondary() with __noendbr

2025-02-14T09:32:05+00:00

The handoff between the boot stubs and start_secondary() are before IBT is enabled and is definitely not subject to kCFI. As such, suppress all that for this function. Notably when the ENDBR poison would become fatal (ud1 instead of nop) this will trigger a tripple fault because we haven't set up the IDT to handle #UD yet. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Sami Tolvanen Link: https://lore.kernel.org/r/20250207122546.509520369@infradead.org

objtool: Fix ANNOTATE_REACHABLE to be a normal annotation

2024-12-02T11:01:44+00:00

Currently REACHABLE is weird for being on the instruction after the instruction it modifies. Since all REACHABLE annotations have an explicit instruction, flip them around. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20241128094312.494176035@infradead.org

objtool: Convert {.UN}REACHABLE to ANNOTATE

2024-12-02T11:01:44+00:00

Suggested-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20241128094312.353431347@infradead.org

objtool: Collect more annotations in objtool.h

2024-12-02T11:01:43+00:00

Suggested-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20241128094311.786598147@infradead.org

objtool: Convert ANNOTATE_INTRA_FUNCTION_CALL to ANNOTATE

2024-12-02T11:01:42+00:00

Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20241128094311.584892071@infradead.org

objtool: Convert VALIDATE_UNRET_BEGIN to ANNOTATE

2024-12-02T11:01:42+00:00

Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20241128094311.358508242@infradead.org

objtool: Convert instrumentation_{begin,end}() to ANNOTATE

2024-12-02T11:01:41+00:00

Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20241128094311.245980207@infradead.org

objtool: Convert ANNOTATE_NOENDBR to ANNOTATE

2024-12-02T11:01:41+00:00

Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20241128094311.042140333@infradead.org