From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yb1-f202.google.com (mail-yb1-f202.google.com [209.85.219.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1B5BB72 for ; Wed, 13 Oct 2021 18:17:35 +0000 (UTC) Received: by mail-yb1-f202.google.com with SMTP id p8-20020a056902114800b005bad2571fbeso3991993ybu.23 for ; Wed, 13 Oct 2021 11:17:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=4Xp81G5gu+GVQC6nDFOKXKxKiHI1/VWta4gwSbjLNy8=; b=lYVdwZp+WUP+p7kjwZi3YG+l5DntTZRPJ2u0QYLrbQeGMwJlDILX5sMscVRVcyQgRU QYIaGEJbDrdrkCXHSB8QLScHi4LISaBgJL5rMHiErMgk7JionKq5V4Pi2b8AMAe44uYY mSg+wC4qohxA1DzHfnar9vyp4IgGq04qZcHWN/bAetbs12V84OWeid44X0WUluDqUTOQ hG4Xb7v6FhLfCRzLwYvk+tx/AO8gW1QTDSxonUXNcfUqTN4HfsjH6H9dKSu4dg0EOtmn LZRroCmn0D5yg5XtUmXUFTCiDPXuUCski7zrptT3RyoHk3HcBNIaXdAzd0V8ibCWDrm/ fR8A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=4Xp81G5gu+GVQC6nDFOKXKxKiHI1/VWta4gwSbjLNy8=; b=6YuxCMkIQpeMqJgHhY2Pf9a99zRPGcVXfKweEm8vjyJ0syE/Fct0O5fIZpVk8dP8Ru a7c1lgtxSj6NX8/uoJaP02bBB0v21l6WkhGt+oWFse+5CAD3hAp9+2KatFE3+kK7WmCu yWjmi3T783eVw6xSbfTTqh8M8jxdYCAL4pnnpEoe/2Un35N2rXPrK01VsJzQwL89aB5I WI1Rx60oGBiJznzZLuiqHRBw+MxGtyT0Uj0seoS/hfs/n9k0eEKMwm00HNZVtpxjYLYt cebEfxBRHONJ9Pq6E5fUNjoCDKOeU37t/SyQ94ALlKjKVqhKD+TpttaJNINMvz4I5GaF 8ORQ== X-Gm-Message-State: AOAM532DZvU1u4y6Gdvu7mnJ/vEGCrorvEWGfuZprLTfPSZRSBNb0qBv MviGSfo/l77lT0EpKOfETdLGPtr5YASa+czq2pE= X-Google-Smtp-Source: ABdhPJwfOX+06p6IWXOO2fyionbsLW/uPZ3rJH/DQZhYPquzPNHFEqW+3Af1FidHpvBclmfhJoQleHN40gKpi9FbUng= X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:9ea6:6c27:1876:926c]) (user=samitolvanen job=sendgmr) by 2002:a25:a089:: with SMTP id y9mr998734ybh.474.1634149054240; Wed, 13 Oct 2021 11:17:34 -0700 (PDT) Date: Wed, 13 Oct 2021 11:16:57 -0700 In-Reply-To: <20211013181658.1020262-1-samitolvanen@google.com> Message-Id: <20211013181658.1020262-15-samitolvanen@google.com> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20211013181658.1020262-1-samitolvanen@google.com> X-Developer-Key: i=samitolvanen@google.com; a=openpgp; fpr=35CCFB63B283D6D3AEB783944CB5F6848BBC56EE X-Developer-Signature: v=1; a=openpgp-sha256; l=1741; h=from:subject; bh=/pDfN4tCkwWT5Z/C8RPpxpsDI4YiDV/Z436g/w8+UyE=; b=owEB7QES/pANAwAKAUy19oSLvFbuAcsmYgBhZyKaMymlHFFQPJvWCB2V+lErjUmlnn1iBJYCBoQa oblgBRuJAbMEAAEKAB0WIQQ1zPtjsoPW0663g5RMtfaEi7xW7gUCYWcimgAKCRBMtfaEi7xW7oHdC/ 9MrKLp0CtcToPDhWw+aY9NAsfBzIC0bTwAuCDUIVvP7ya3YdaC7ArJtJrTIcuEhoJkbvyRQhYf9sLF NHIbeEs63iMVP9eo1hyZJh2n21vIyVLr2hZCTKMaKDnvwCoXHJmka/ZWnlCp2dcZwb7SXNI/C+2Jn9 uoxMqqBFkg0dDrin1EDCfxsbOjjyVsLdp4rV0Rj3ByH21+bBM4dukk+HJHSUfWcfgys75A3Wj1nFEV JI5kRiSelHD1OMpVUKEFNW1O+ld4UAmE6SCbVk1y1O6U/6csLeiTG0TYwQeqUHzctwWfidE65Xm4wI FhK+23zt5GFpmpejHlIzC5qYAY2lSdt9Mo2qVwy4H4R6EWK6tbmz+YHXRhKl2NUXOd/zIdmtOsoM1b /+TtR3EQUUJlN8X5iUkXFUSjI12eL0eU0A7YPnf7PQo8wvDOflbPQcQPYbuPDkpYOzJqRwqKeJBQUG erZ7/C4jOv53BDYZySy5jJl2vQY9PUGwog7UhwV29fpWM= X-Mailer: git-send-email 2.33.0.1079.g6e70778dc9-goog Subject: [PATCH v5 14/15] x86, kprobes: Fix optprobe_template_func type mismatch From: Sami Tolvanen To: x86@kernel.org Cc: Kees Cook , Josh Poimboeuf , Peter Zijlstra , Nathan Chancellor , Nick Desaulniers , Sedat Dilek , Steven Rostedt , linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" The optprobe_template_func symbol is defined in inline assembly, but it's not marked global, which conflicts with the C declaration needed for STACK_FRAME_NON_STANDARD and confuses the compiler when CONFIG_CFI_CLANG is enabled. Marking the symbol global would make the compiler happy, but as the compiler also generates a CFI jump table entry for all address-taken functions, the jump table ends up containing a jump to the .rodata section where optprobe_template_func resides, which results in an objtool warning. Use ASM_STACK_FRAME_NON_STANDARD instead to avoid both issues. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Nick Desaulniers Tested-by: Sedat Dilek --- arch/x86/kernel/kprobes/opt.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index 71425ebba98a..95375ef5deee 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -103,6 +103,7 @@ static void synthesize_set_arg1(kprobe_opcode_t *addr, unsigned long val) asm ( ".pushsection .rodata\n" "optprobe_template_func:\n" + ASM_STACK_FRAME_NON_STANDARD(optprobe_template_func) ".global optprobe_template_entry\n" "optprobe_template_entry:\n" #ifdef CONFIG_X86_64 @@ -154,9 +155,6 @@ asm ( "optprobe_template_end:\n" ".popsection\n"); -void optprobe_template_func(void); -STACK_FRAME_NON_STANDARD(optprobe_template_func); - #define TMPL_CLAC_IDX \ ((long)optprobe_template_clac - (long)optprobe_template_entry) #define TMPL_MOVE_IDX \ -- 2.33.0.1079.g6e70778dc9-goog