Peter Zijlstra dab72c3c32 objtool: Add entry UNRET validation ... commit a09a6e2399 upstream. Since entry asm is tricky, add a validation pass that ensures the retbleed mitigation has been done before the first actual RET instruction. Entry points are those that either have UNWIND_HINT_ENTRY, which acts as UNWIND_HINT_EMPTY but marks the instruction as an entry point, or those that have UWIND_HINT_IRET_REGS at +0. This is basically a variant of validate_branch() that is intra-function and it will simply follow all branches from marked entry points and ensures that all paths lead to ANNOTATE_UNRET_END. If a path hits RET or an indirection the path is a fail and will be reported. There are 3 ANNOTATE_UNRET_END instances: - UNTRAIN_RET itself - exception from-kernel; this path doesn't need UNTRAIN_RET - all early exceptions; these also don't need UNTRAIN_RET Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Borislav Petkov <bp@suse.de> [cascardo: tools/objtool/builtin-check.c no link option validation] [cascardo: tools/objtool/check.c opts.ibt is ibt] [cascardo: tools/objtool/include/objtool/builtin.h leave unret option as bool, no struct opts] [cascardo: objtool is still called from scripts/link-vmlinux.sh] [cascardo: no IBT support] Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-07-23 12:54:06 +02:00
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asm	tools arch: Update arch/x86/lib/mem{cpy,set}_64.S copies used in 'perf bench mem memcpy'	2021-05-10 09:01:00 -03:00
asm-generic	x86/insn: Use get_unaligned() instead of memcpy()	2021-11-18 19:16:30 +01:00
linux	objtool: Add entry UNRET validation	2022-07-23 12:54:06 +02:00
nolibc	tools/nolibc: fix incorrect truncation of exit code	2022-01-27 11:02:51 +01:00
tools
trace/events
uapi	bpf: Fix comment for helper bpf_current_task_under_cgroup()	2022-04-08 14:24:14 +02:00
vdso	tools headers: Synchronize linux/bits.h with the kernel sources	2020-04-14 11:40:05 -03:00