Module Name: src
Committed By: maxv
Date: Mon Sep 25 20:39:21 UTC 2017
Modified Files:
src/sys/lib/libsa: loadfile_elf32.c
Log Message:
Clean up and split loadfile, reduces a patch I have.
To generate a diff of this commit:
cvs rdiff -u -r1.40 -r1.41 src/sys/lib/libsa/loadfile_elf32.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/lib/libsa/loadfile_elf32.c
diff -u src/sys/lib/libsa/loadfile_elf32.c:1.40 src/sys/lib/libsa/loadfile_elf32.c:1.41
--- src/sys/lib/libsa/loadfile_elf32.c:1.40 Tue Apr 18 07:44:20 2017
+++ src/sys/lib/libsa/loadfile_elf32.c Mon Sep 25 20:39:21 2017
@@ -1,12 +1,12 @@
-/* $NetBSD: loadfile_elf32.c,v 1.40 2017/04/18 07:44:20 uwe Exp $ */
+/* $NetBSD: loadfile_elf32.c,v 1.41 2017/09/25 20:39:21 maxv Exp $ */
/*
- * Copyright (c) 1997, 2008 The NetBSD Foundation, Inc.
+ * Copyright (c) 1997, 2008, 2017 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
- * NASA Ames Research Center and by Christos Zoulas.
+ * NASA Ames Research Center, by Christos Zoulas, and by Maxime Villard.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -259,8 +259,220 @@ externalize_shdr(Elf_Byte bo, Elf_Shdr *
#define IS_DATA(p) (p.p_flags & PF_W)
#define IS_BSS(p) (p.p_filesz < p.p_memsz)
+#ifndef MD_LOADSEG /* Allow processor ABI specific segment loads */
+#define MD_LOADSEG(a) /*CONSTCOND*/0
+#endif
+
+/* -------------------------------------------------------------------------- */
+
/*
- * Load the ELF binary into memory. Layout of the memory:
+ * See comment below. This function is in charge of loading the SECTION HEADERS.
+ */
+static int
+ELFNAMEEND(loadsym)(int fd, Elf_Ehdr *elf, Elf_Addr maxp, Elf_Addr elfp,
+ u_long *marks, int flags, Elf_Addr *nmaxp)
+{
+ int boot_load_ctf = 1;
+ Elf_Shdr *shp;
+ Elf_Addr shpp;
+ char *shstr = NULL;
+ ssize_t nr, sz;
+ size_t i, j, shstrsz = 0;
+ u_long offset = marks[MARK_START];
+ struct __packed {
+ Elf_Nhdr nh;
+ uint8_t name[ELF_NOTE_NETBSD_NAMESZ + 1];
+ uint8_t desc[ELF_NOTE_NETBSD_DESCSZ];
+ } note;
+ int first;
+
+ /* some ports dont use the offset */
+ (void)&offset;
+
+ if (lseek(fd, elf->e_shoff, SEEK_SET) == -1) {
+ WARN(("lseek section headers"));
+ return -1;
+ }
+ sz = elf->e_shnum * sizeof(Elf_Shdr);
+ shp = ALLOC(sz);
+
+ nr = read(fd, shp, sz);
+ if (nr == -1) {
+ WARN(("read section headers"));
+ goto out;
+ }
+ if (nr != sz) {
+ errno = EIO;
+ WARN(("read section headers"));
+ goto out;
+ }
+
+ shpp = maxp;
+ maxp += roundup(sz, ELFROUND);
+
+#ifndef _STANDALONE
+ for (i = 0; i < elf->e_shnum; i++)
+ internalize_shdr(elf->e_ident[EI_DATA], &shp[i]);
+#endif
+
+ /*
+ * First load the section names section. Only useful for CTF.
+ */
+ if (boot_load_ctf && (elf->e_shstrndx != SHN_UNDEF)) {
+ Elf_Off shstroff = shp[elf->e_shstrndx].sh_offset;
+ shstrsz = shp[elf->e_shstrndx].sh_size;
+ if (flags & LOAD_SYM) {
+ if (lseek(fd, shstroff, SEEK_SET) == -1) {
+ WARN(("lseek symbols"));
+ goto out;
+ }
+ nr = READ(fd, maxp, shstrsz);
+ if (nr == -1) {
+ WARN(("read symbols"));
+ goto out;
+ }
+ if (nr != (ssize_t)shstrsz) {
+ errno = EIO;
+ WARN(("read symbols"));
+ goto out;
+ }
+ }
+
+ /* Create a local copy */
+ shstr = ALLOC(shstrsz);
+ if (lseek(fd, shstroff, SEEK_SET) == -1) {
+ WARN(("lseek symbols"));
+ goto out;
+ }
+ nr = read(fd, shstr, shstrsz);
+ if (nr == -1) {
+ WARN(("read symbols"));
+ goto out;
+ }
+ shp[elf->e_shstrndx].sh_offset = maxp - elfp;
+ maxp += roundup(shstrsz, ELFROUND);
+ }
+
+ /*
+ * Now load the symbol sections themselves. Make sure the sections are
+ * ELFROUND-aligned. Update sh_offset to be relative to elfp. Set it to
+ * zero when we don't want the sections to be taken care of, the kernel
+ * will properly skip them.
+ */
+ first = 1;
+ for (i = 1; i < elf->e_shnum; i++) {
+ if (i == elf->e_shstrndx) {
+ /* already loaded this section */
+ continue;
+ }
+
+ switch (shp[i].sh_type) {
+ case SHT_PROGBITS:
+ if (boot_load_ctf && shstr) {
+ /* got a CTF section? */
+ if (strncmp(&shstr[shp[i].sh_name],
+ ".SUNW_ctf", 10) == 0) {
+ goto havesym;
+ }
+ }
+
+ shp[i].sh_offset = 0;
+ break;
+ case SHT_STRTAB:
+ for (j = 1; j < elf->e_shnum; j++)
+ if (shp[j].sh_type == SHT_SYMTAB &&
+ shp[j].sh_link == (unsigned int)i)
+ goto havesym;
+ /*
+ * Don't bother with any string table that isn't
+ * referenced by a symbol table.
+ */
+ shp[i].sh_offset = 0;
+ break;
+havesym:
+ case SHT_SYMTAB:
+ if (flags & LOAD_SYM) {
+ PROGRESS(("%s%ld", first ? " [" : "+",
+ (u_long)shp[i].sh_size));
+ if (lseek(fd, shp[i].sh_offset,
+ SEEK_SET) == -1) {
+ WARN(("lseek symbols"));
+ goto out;
+ }
+ nr = READ(fd, maxp, shp[i].sh_size);
+ if (nr == -1) {
+ WARN(("read symbols"));
+ goto out;
+ }
+ if (nr != (ssize_t)shp[i].sh_size) {
+ errno = EIO;
+ WARN(("read symbols"));
+ goto out;
+ }
+ }
+ shp[i].sh_offset = maxp - elfp;
+ maxp += roundup(shp[i].sh_size, ELFROUND);
+ first = 0;
+ break;
+ case SHT_NOTE:
+ if ((flags & LOAD_NOTE) == 0)
+ break;
+ if (shp[i].sh_size < sizeof(note)) {
+ shp[i].sh_offset = 0;
+ break;
+ }
+ if (lseek(fd, shp[i].sh_offset, SEEK_SET) == -1) {
+ WARN(("lseek note"));
+ goto out;
+ }
+ nr = read(fd, ¬e, sizeof(note));
+ if (nr == -1) {
+ WARN(("read note"));
+ goto out;
+ }
+ if (note.nh.n_namesz == ELF_NOTE_NETBSD_NAMESZ &&
+ note.nh.n_descsz == ELF_NOTE_NETBSD_DESCSZ &&
+ note.nh.n_type == ELF_NOTE_TYPE_NETBSD_TAG &&
+ memcmp(note.name, ELF_NOTE_NETBSD_NAME,
+ sizeof(note.name)) == 0) {
+ memcpy(&netbsd_version, ¬e.desc,
+ sizeof(netbsd_version));
+ }
+ shp[i].sh_offset = 0;
+ break;
+ default:
+ shp[i].sh_offset = 0;
+ break;
+ }
+ }
+ if (flags & LOAD_SYM) {
+#ifndef _STANDALONE
+ for (i = 0; i < elf->e_shnum; i++)
+ externalize_shdr(elf->e_ident[EI_DATA], &shp[i]);
+#endif
+ BCOPY(shp, shpp, sz);
+
+ if (first == 0)
+ PROGRESS(("]"));
+ }
+
+ *nmaxp = maxp;
+ DEALLOC(shp, sz);
+ if (shstr != NULL)
+ DEALLOC(shstr, shstrsz);
+ return 0;
+
+out:
+ DEALLOC(shp, sz);
+ if (shstr != NULL)
+ DEALLOC(shstr, shstrsz);
+ return -1;
+}
+
+/* -------------------------------------------------------------------------- */
+
+/*
+ * Load a static ELF binary into memory. Layout of the memory:
* +-----------------+------------+-----------------+-----------------+
* | KERNEL SEGMENTS | ELF HEADER | SECTION HEADERS | SYMBOL SECTIONS |
* +-----------------+------------+-----------------+-----------------+
@@ -273,27 +485,15 @@ externalize_shdr(Elf_Byte bo, Elf_Shdr *
* We just give the kernel a pointer to the ELF HEADER, which is enough for it
* to find the location and number of symbols by itself later.
*/
-
int
ELFNAMEEND(loadfile)(int fd, Elf_Ehdr *elf, u_long *marks, int flags)
{
- Elf_Shdr *shp;
Elf_Phdr *phdr;
- int i, j;
+ int i, first;
ssize_t sz;
- int first;
- Elf_Addr shpp;
Elf_Addr minp = ~0, maxp = 0, pos = 0, elfp = 0;
u_long offset = marks[MARK_START];
ssize_t nr;
- struct __packed {
- Elf_Nhdr nh;
- uint8_t name[ELF_NOTE_NETBSD_NAMESZ + 1];
- uint8_t desc[ELF_NOTE_NETBSD_DESCSZ];
- } note;
- char *shstr = NULL;
- size_t shstrsz = 0;
- int boot_load_ctf = 1;
/* some ports dont use the offset */
(void)&offset;
@@ -325,9 +525,6 @@ ELFNAMEEND(loadfile)(int fd, Elf_Ehdr *e
for (i = 0; i < elf->e_phnum; i++) {
internalize_phdr(elf->e_ident[EI_DATA], &phdr[i]);
-#ifndef MD_LOADSEG /* Allow processor ABI specific segment loads */
-#define MD_LOADSEG(a) /*CONSTCOND*/0
-#endif
if (MD_LOADSEG(&phdr[i]))
goto loadseg;
@@ -390,194 +587,25 @@ ELFNAMEEND(loadfile)(int fd, Elf_Ehdr *e
}
}
DEALLOC(phdr, sz);
+ maxp = roundup(maxp, ELFROUND);
/*
- * Copy the ELF and section headers.
+ * Load the ELF HEADER, SECTION HEADERS and possibly the SYMBOL
+ * SECTIONS.
*/
- maxp = roundup(maxp, ELFROUND);
if (flags & (LOAD_HDR|COUNT_HDR)) {
elfp = maxp;
maxp += sizeof(Elf_Ehdr);
}
-
if (flags & (LOAD_SYM|COUNT_SYM)) {
- if (lseek(fd, elf->e_shoff, SEEK_SET) == -1) {
- WARN(("lseek section headers"));
- return 1;
- }
- sz = elf->e_shnum * sizeof(Elf_Shdr);
-
- shp = ALLOC(sz);
-
- nr = read(fd, shp, sz);
- if (nr == -1) {
- WARN(("read section headers"));
- goto freeshp;
- }
- if (nr != sz) {
- errno = EIO;
- WARN(("read section headers"));
- goto freeshp;
- }
-
- shpp = maxp;
- maxp += roundup(sz, ELFROUND);
-
-#ifndef _STANDALONE
- /* Internalize the section headers. */
- for (i = 0; i < elf->e_shnum; i++)
- internalize_shdr(elf->e_ident[EI_DATA], &shp[i]);
-#endif
-
- /*
- * First load the section names section.
- */
- if (boot_load_ctf && (elf->e_shstrndx != SHN_UNDEF)) {
- Elf_Off shstroff = shp[elf->e_shstrndx].sh_offset;
- shstrsz = shp[elf->e_shstrndx].sh_size;
- if (flags & LOAD_SYM) {
- if (lseek(fd, shstroff, SEEK_SET) == -1) {
- WARN(("lseek symbols"));
- goto freeshp;
- }
- nr = READ(fd, maxp, shstrsz);
- if (nr == -1) {
- WARN(("read symbols"));
- goto freeshp;
- }
- if (nr != (ssize_t)shstrsz) {
- errno = EIO;
- WARN(("read symbols"));
- goto freeshp;
- }
- }
-
- shstr = ALLOC(shstrsz);
- if (lseek(fd, shstroff, SEEK_SET) == -1) {
- WARN(("lseek symbols"));
- goto freeshp;
- }
- nr = read(fd, shstr, shstrsz);
- if (nr == -1) {
- WARN(("read symbols"));
- goto freeshp;
- }
- shp[elf->e_shstrndx].sh_offset = maxp - elfp;
- maxp += roundup(shstrsz, ELFROUND);
+ if (ELFNAMEEND(loadsym)(fd, elf, maxp, elfp, marks, flags,
+ &maxp) == -1) {
+ return 1;
}
-
- /*
- * Now load the symbol sections themselves. Make sure
- * the sections are aligned. Don't bother with any
- * string table that isn't referenced by a symbol
- * table.
- */
- first = 1;
- for (i = 1; i < elf->e_shnum; i++) {
- if (i == elf->e_shstrndx) {
- /* already loaded this section */
- continue;
- }
- switch (shp[i].sh_type) {
- case SHT_PROGBITS:
- if (boot_load_ctf && shstr) {
- /* got a CTF section? */
- if (strncmp(&shstr[shp[i].sh_name],
- ".SUNW_ctf", 10) == 0) {
- goto havesym;
- }
- }
-
- /* Not loading this, so zero out the offset. */
- shp[i].sh_offset = 0;
- break;
- case SHT_STRTAB:
- for (j = 1; j < elf->e_shnum; j++)
- if (shp[j].sh_type == SHT_SYMTAB &&
- shp[j].sh_link == (unsigned int)i)
- goto havesym;
- /* FALLTHROUGH */
- default:
- /* Not loading this, so zero out the offset. */
- shp[i].sh_offset = 0;
- break;
- havesym:
- case SHT_SYMTAB:
- if (flags & LOAD_SYM) {
- PROGRESS(("%s%ld", first ? " [" : "+",
- (u_long)shp[i].sh_size));
- if (lseek(fd, shp[i].sh_offset,
- SEEK_SET) == -1) {
- WARN(("lseek symbols"));
- goto freeshp;
- }
- nr = READ(fd, maxp, shp[i].sh_size);
- if (nr == -1) {
- WARN(("read symbols"));
- goto freeshp;
- }
- if (nr != (ssize_t)shp[i].sh_size) {
- errno = EIO;
- WARN(("read symbols"));
- goto freeshp;
- }
- }
- shp[i].sh_offset = maxp - elfp;
- maxp += roundup(shp[i].sh_size, ELFROUND);
- first = 0;
- break;
- case SHT_NOTE:
- if ((flags & LOAD_NOTE) == 0)
- break;
- if (shp[i].sh_size < sizeof(note)) {
- shp[i].sh_offset = 0;
- break;
- }
- if (lseek(fd, shp[i].sh_offset, SEEK_SET)
- == -1) {
- WARN(("lseek note"));
- goto freeshp;
- }
- nr = read(fd, ¬e, sizeof(note));
- if (nr == -1) {
- WARN(("read note"));
- goto freeshp;
- }
- if (note.nh.n_namesz ==
- ELF_NOTE_NETBSD_NAMESZ &&
- note.nh.n_descsz ==
- ELF_NOTE_NETBSD_DESCSZ &&
- note.nh.n_type ==
- ELF_NOTE_TYPE_NETBSD_TAG &&
- memcmp(note.name, ELF_NOTE_NETBSD_NAME,
- sizeof(note.name)) == 0) {
- memcpy(&netbsd_version, ¬e.desc,
- sizeof(netbsd_version));
- }
- shp[i].sh_offset = 0;
- break;
- }
- }
- if (flags & LOAD_SYM) {
-#ifndef _STANDALONE
- /* Externalize the section headers. */
- for (i = 0; i < elf->e_shnum; i++)
- externalize_shdr(elf->e_ident[EI_DATA],
- &shp[i]);
-#endif
- BCOPY(shp, shpp, sz);
-
- if (first == 0)
- PROGRESS(("]"));
- }
- DEALLOC(shp, sz);
- if (shstr)
- DEALLOC(shstr, shstrsz);
}
/*
- * Frob the copied ELF header to give information relative
- * to elfp.
+ * Update the ELF HEADER to give information relative to elfp.
*/
if (flags & LOAD_HDR) {
elf->e_phoff = 0;
@@ -591,13 +619,6 @@ ELFNAMEEND(loadfile)(int fd, Elf_Ehdr *e
marks[MARK_START] = LOADADDR(minp);
marks[MARK_ENTRY] = LOADADDR(elf->e_entry);
- /*
- * Since there can be more than one symbol section in the code
- * and we need to find strtab too in order to do anything
- * useful with the symbols, we just pass the whole elf
- * header back and we let the kernel debugger find the
- * location and number of symbols by itself.
- */
marks[MARK_NSYM] = 1; /* XXX: Kernel needs >= 0 */
marks[MARK_SYM] = LOADADDR(elfp);
marks[MARK_END] = LOADADDR(maxp);
@@ -606,38 +627,6 @@ ELFNAMEEND(loadfile)(int fd, Elf_Ehdr *e
freephdr:
DEALLOC(phdr, sz);
return 1;
-
-freeshp:
- DEALLOC(shp, sz);
- return 1;
}
-#ifdef TEST
-#include <stdlib.h>
-#include <fcntl.h>
-#include <err.h>
-#include <stdio.h>
-u_int32_t netbsd_version;
-int
-main(int argc, char *argv[])
-{
- int fd;
- u_long marks[MARK_MAX];
- Elf_Ehdr elf;
- if (argc != 2) {
- (void)fprintf(stderr, "Usage: %s <file>\n", getprogname());
- return 1;
- }
- if ((fd = open(argv[1], O_RDONLY)) == -1)
- err(1, "Can't open `%s'", argv[1]);
- if (read(fd, &elf, sizeof(elf)) != sizeof(elf))
- err(1, "Can't read `%s'", argv[1]);
- memset(marks, 0, sizeof(marks));
- marks[MARK_START] = (u_long)malloc(2LL * 1024 * 2024 * 1024);
- ELFNAMEEND(loadfile)(fd, &elf, marks, LOAD_ALL);
- printf("%d\n", netbsd_version);
- return 0;
-}
-#endif
-
#endif /* (ELFSIZE == 32 && BOOT_ELF32) || (ELFSIZE == 64 && BOOT_ELF64) */
