From patchwork Tue May 29 22:15:27 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Garnier X-Patchwork-Id: 10437347 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id ACE6B601E9 for ; Tue, 29 May 2018 22:23:22 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 974FC28236 for ; Tue, 29 May 2018 22:23:22 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8BD8D286BE; Tue, 29 May 2018 22:23:22 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id 60F1928236 for ; Tue, 29 May 2018 22:23:21 +0000 (UTC) Received: (qmail 23843 invoked by uid 550); 29 May 2018 22:18:35 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 23768 invoked from network); 29 May 2018 22:18:32 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=9y4mL1N7jEIVWjL94WzknwWKjgV561ZdkhyUvn+ff1w=; b=LTXCR+yntZFtieqyRHnARiGBaRnfto/kqcrjt+BUpJ00FwRKwhgH0OQMQMc6cOCKNZ fFms9oSXvAmHYKpf66qkulZFnNMmFohP96Z+g+ZglVT5KaJSpWV11ECPEDOrRYuJxfKc 4OYgzqLaC5qlg9vzo4D4aJQeRZvTbc4abPLHFPVpn2J9raLX8Hdu9A3Yl7xbgTusb76g c/ytbtsJD2gN/4Nw2Gc53Ciw61tvj+hDMx6HtloaqBnoL0OzJElVzS0AH+YcR1nb9vEa AnjJEQBiUeb5/sZB5KPLSZC/BeqF0ALbys9D5bCxULWECDCxmrkXnlR3ksicgllTUH2U jc9g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=9y4mL1N7jEIVWjL94WzknwWKjgV561ZdkhyUvn+ff1w=; b=XAAHzkyJgbuXAJBvPUNl0rawsBYKuPBSHun+ZR2d3VUD42vssypGDYbZtjyz7rh3H+ zAy/ERt9xs1gtQs3rg0fMd6BQBmGa4Ps8sFPBrG1wF4fAGVBt42nvPktw3MOb4VZ/VTf 4yUnj8TijUrf6H3aOjaj7rrdoJfcPJ6wByNJGOSi25aohRTDo3SJ6amAE5wR39PPfyq1 rcLIiN4hU5jMwwNGiOCIK96Xe248QE6dY8dT1htG0Ry6YZYbvDWGwzRp13g5DNkERJGz 47Q+zGOpEJ4ci9KwE3223qQDHkO+mDuVWSuy0v0DzZOuk6hjZoy0pG2j8BiOvcmKhgGY mMYw== X-Gm-Message-State: ALKqPwdMRDVdjTH+mI/sUZxtb6SH328yBvBF6NwoIukQBO6yZ3qDk8YM CfaneiCFj86XVd6su5HblRBJ/JjTy/I= X-Google-Smtp-Source: ADUXVKI0RGHALQ+SVYnYqfH5k+Ds2bz2f8JuAffPlGTrNtAi5c7u7Wzzm/n2ynoC6KwJjpzofCOB7A== X-Received: by 2002:a17:902:704c:: with SMTP id h12-v6mr204187plt.269.1527632300277; Tue, 29 May 2018 15:18:20 -0700 (PDT) From: Thomas Garnier To: kernel-hardening@lists.openwall.com Cc: Thomas Garnier , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Kate Stewart , "H.J. Lu" , Greg Kroah-Hartman , Philippe Ombredanne , linux-kernel@vger.kernel.org Subject: [PATCH v4 26/27] x86/relocs: Add option to generate 64-bit relocations Date: Tue, 29 May 2018 15:15:27 -0700 Message-Id: <20180529221625.33541-27-thgarnie@google.com> X-Mailer: git-send-email 2.17.0.921.gf22659ad46-goog In-Reply-To: <20180529221625.33541-1-thgarnie@google.com> References: <20180529221625.33541-1-thgarnie@google.com> X-Virus-Scanned: ClamAV using ClamSMTP The x86 relocation tool generates a list of 32-bit signed integers. There was no need to use 64-bit integers because all addresses where above the 2G top of the memory. This change add a large-reloc option to generate 64-bit unsigned integers. It can be used when the kernel plan to go below the top 2G and 32-bit integers are not enough. Signed-off-by: Thomas Garnier --- arch/x86/tools/relocs.c | 60 +++++++++++++++++++++++++++------- arch/x86/tools/relocs.h | 4 +-- arch/x86/tools/relocs_common.c | 15 ++++++--- 3 files changed, 60 insertions(+), 19 deletions(-) diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c index 29283ad3950f..a29cccceaac6 100644 --- a/arch/x86/tools/relocs.c +++ b/arch/x86/tools/relocs.c @@ -13,8 +13,14 @@ static Elf_Ehdr ehdr; +#if ELF_BITS == 64 +typedef uint64_t rel_off_t; +#else +typedef uint32_t rel_off_t; +#endif + struct relocs { - uint32_t *offset; + rel_off_t *offset; unsigned long count; unsigned long size; }; @@ -685,7 +691,7 @@ static void print_absolute_relocs(void) printf("\n"); } -static void add_reloc(struct relocs *r, uint32_t offset) +static void add_reloc(struct relocs *r, rel_off_t offset) { if (r->count == r->size) { unsigned long newsize = r->size + 50000; @@ -1061,26 +1067,48 @@ static void sort_relocs(struct relocs *r) qsort(r->offset, r->count, sizeof(r->offset[0]), cmp_relocs); } -static int write32(uint32_t v, FILE *f) +static int write32(rel_off_t rel, FILE *f) { - unsigned char buf[4]; + unsigned char buf[sizeof(uint32_t)]; + uint32_t v = (uint32_t)rel; put_unaligned_le32(v, buf); - return fwrite(buf, 1, 4, f) == 4 ? 0 : -1; + return fwrite(buf, 1, sizeof(buf), f) == sizeof(buf) ? 0 : -1; } -static int write32_as_text(uint32_t v, FILE *f) +static int write32_as_text(rel_off_t rel, FILE *f) { + uint32_t v = (uint32_t)rel; return fprintf(f, "\t.long 0x%08"PRIx32"\n", v) > 0 ? 0 : -1; } -static void emit_relocs(int as_text, int use_real_mode) +static int write64(rel_off_t rel, FILE *f) +{ + unsigned char buf[sizeof(uint64_t)]; + uint64_t v = (uint64_t)rel; + + put_unaligned_le64(v, buf); + return fwrite(buf, 1, sizeof(buf), f) == sizeof(buf) ? 0 : -1; +} + +static int write64_as_text(rel_off_t rel, FILE *f) +{ + uint64_t v = (uint64_t)rel; + return fprintf(f, "\t.quad 0x%016"PRIx64"\n", v) > 0 ? 0 : -1; +} + +static void emit_relocs(int as_text, int use_real_mode, int use_large_reloc) { int i; - int (*write_reloc)(uint32_t, FILE *) = write32; + int (*write_reloc)(rel_off_t, FILE *); int (*do_reloc)(struct section *sec, Elf_Rel *rel, Elf_Sym *sym, const char *symname); + if (use_large_reloc) + write_reloc = write64; + else + write_reloc = write32; + #if ELF_BITS == 64 if (!use_real_mode) do_reloc = do_reloc64; @@ -1091,6 +1119,9 @@ static void emit_relocs(int as_text, int use_real_mode) do_reloc = do_reloc32; else do_reloc = do_reloc_real; + + /* Large relocations only for 64-bit */ + use_large_reloc = 0; #endif /* Collect up the relocations */ @@ -1114,8 +1145,13 @@ static void emit_relocs(int as_text, int use_real_mode) * gas will like. */ printf(".section \".data.reloc\",\"a\"\n"); - printf(".balign 4\n"); - write_reloc = write32_as_text; + if (use_large_reloc) { + printf(".balign 8\n"); + write_reloc = write64_as_text; + } else { + printf(".balign 4\n"); + write_reloc = write32_as_text; + } } if (use_real_mode) { @@ -1183,7 +1219,7 @@ static void print_reloc_info(void) void process(FILE *fp, int use_real_mode, int as_text, int show_absolute_syms, int show_absolute_relocs, - int show_reloc_info) + int show_reloc_info, int use_large_reloc) { regex_init(use_real_mode); read_ehdr(fp); @@ -1206,5 +1242,5 @@ void process(FILE *fp, int use_real_mode, int as_text, print_reloc_info(); return; } - emit_relocs(as_text, use_real_mode); + emit_relocs(as_text, use_real_mode, use_large_reloc); } diff --git a/arch/x86/tools/relocs.h b/arch/x86/tools/relocs.h index 43c83c0fd22c..3d401da59df7 100644 --- a/arch/x86/tools/relocs.h +++ b/arch/x86/tools/relocs.h @@ -31,8 +31,8 @@ enum symtype { void process_32(FILE *fp, int use_real_mode, int as_text, int show_absolute_syms, int show_absolute_relocs, - int show_reloc_info); + int show_reloc_info, int use_large_reloc); void process_64(FILE *fp, int use_real_mode, int as_text, int show_absolute_syms, int show_absolute_relocs, - int show_reloc_info); + int show_reloc_info, int use_large_reloc); #endif /* RELOCS_H */ diff --git a/arch/x86/tools/relocs_common.c b/arch/x86/tools/relocs_common.c index 6634352a20bc..11f49adf1c06 100644 --- a/arch/x86/tools/relocs_common.c +++ b/arch/x86/tools/relocs_common.c @@ -12,14 +12,14 @@ void die(char *fmt, ...) static void usage(void) { - die("relocs [--abs-syms|--abs-relocs|--reloc-info|--text|--realmode]" \ - " vmlinux\n"); + die("relocs [--abs-syms|--abs-relocs|--reloc-info|--text|--realmode|" \ + "--large-reloc] vmlinux\n"); } int main(int argc, char **argv) { int show_absolute_syms, show_absolute_relocs, show_reloc_info; - int as_text, use_real_mode; + int as_text, use_real_mode, use_large_reloc; const char *fname; FILE *fp; int i; @@ -30,6 +30,7 @@ int main(int argc, char **argv) show_reloc_info = 0; as_text = 0; use_real_mode = 0; + use_large_reloc = 0; fname = NULL; for (i = 1; i < argc; i++) { char *arg = argv[i]; @@ -54,6 +55,10 @@ int main(int argc, char **argv) use_real_mode = 1; continue; } + if (strcmp(arg, "--large-reloc") == 0) { + use_large_reloc = 1; + continue; + } } else if (!fname) { fname = arg; @@ -75,11 +80,11 @@ int main(int argc, char **argv) if (e_ident[EI_CLASS] == ELFCLASS64) process_64(fp, use_real_mode, as_text, show_absolute_syms, show_absolute_relocs, - show_reloc_info); + show_reloc_info, use_large_reloc); else process_32(fp, use_real_mode, as_text, show_absolute_syms, show_absolute_relocs, - show_reloc_info); + show_reloc_info, use_large_reloc); fclose(fp); return 0; }