Another update from Larry:
[oweals/busybox.git] / insmod.c
index 7af135902a9e9e49a0af0534bee265355343b076..27f4a50e2045123f0aa1ce7da403bea9385a8c42 100644 (file)
--- a/insmod.c
+++ b/insmod.c
@@ -1,6 +1,7 @@
 /* vi: set sw=4 ts=4: */
 /*
  * Mini insmod implementation for busybox
+ * This version of insmod now supports x86, ARM, SH3/4, powerpc, and MIPS.
  *
  * Copyright (C) 1999,2000,2001 by Lineo, inc.
  * Written by Erik Andersen <andersen@lineo.com>
  *   I've only tested the code on mpc8xx platforms in big-endian mode.
  *   Did some cleanup and added BB_USE_xxx_ENTRIES...
  *
+ * Quinn Jensen <jensenq@lineo.com> added MIPS support 23-Feb-2001.
+ *   based on modutils-2.4.2
+ *   MIPS specific support for Elf loading and relocation.
+ *   Copyright 1996, 1997 Linux International.
+ *   Contributed by Ralf Baechle <ralf@gnu.ai.mit.edu>
+ *
  * Based almost entirely on the Linux modutils-2.3.11 implementation.
  *   Copyright 1996, 1997 Linux International.
  *   New implementation contributed by Richard Henderson <rth@tamu.edu>
 #include <string.h>
 #include <getopt.h>
 #include <sys/utsname.h>
-#include <sys/syscall.h>
-#include <linux/unistd.h>
 #include "busybox.h"
 
+#ifdef BB_FEATURE_NEW_MODULE_INTERFACE
+# define new_sys_init_module   init_module
+#else
+# define old_sys_init_module   init_module
+#endif
+
 #if defined(__powerpc__)
 #define BB_USE_PLT_ENTRIES
 #define BB_PLT_ENTRY_SIZE 16
 #define BB_GOT_ENTRY_SIZE 4
 #endif
 
+#if defined(__mips__)
+// neither used
+#endif
+
 //----------------------------------------------------------------------------
 //--------modutils module.h, lines 45-242
 //----------------------------------------------------------------------------
 #ifndef MODUTILS_MODULE_H
 static const int MODUTILS_MODULE_H = 1;
 
-#ident "$Id: insmod.c,v 1.49 2001/02/20 20:47:08 andersen Exp $"
+#ident "$Id: insmod.c,v 1.60 2001/04/26 19:29:58 andersen Exp $"
 
 /* This file contains the structures used by the 2.0 and 2.1 kernels.
    We do not use the kernel headers directly because we do not wish
@@ -315,7 +330,7 @@ int delete_module(const char *);
 #ifndef MODUTILS_OBJ_H
 static const int MODUTILS_OBJ_H = 1;
 
-#ident "$Id: insmod.c,v 1.49 2001/02/20 20:47:08 andersen Exp $"
+#ident "$Id: insmod.c,v 1.60 2001/04/26 19:29:58 andersen Exp $"
 
 /* The relocatable object is manipulated using elfin types.  */
 
@@ -361,6 +376,27 @@ static const int MODUTILS_OBJ_H = 1;
 #define Elf32_RelM     Elf32_Rela
 #define ELFDATAM        ELFDATA2MSB
 
+#elif defined(__mips__)
+
+/* Account for ELF spec changes.  */
+#ifndef EM_MIPS_RS3_LE
+#ifdef EM_MIPS_RS4_BE
+#define EM_MIPS_RS3_LE EM_MIPS_RS4_BE
+#else
+#define EM_MIPS_RS3_LE 10
+#endif
+#endif /* !EM_MIPS_RS3_LE */
+
+#define MATCH_MACHINE(x) (x == EM_MIPS || x == EM_MIPS_RS3_LE)
+#define SHT_RELM       SHT_REL
+#define Elf32_RelM     Elf32_Rel
+#ifdef __MIPSEB__
+#define ELFDATAM        ELFDATA2MSB
+#endif
+#ifdef __MIPSEL__
+#define ELFDATAM        ELFDATA2LSB
+#endif
+
 #elif defined(__i386__)
 
 /* presumably we can use these for anything but the SH and ARM*/
@@ -594,6 +630,15 @@ struct arch_got_entry {
 };
 #endif
 
+#if defined(__mips__)
+struct mips_hi16
+{
+  struct mips_hi16 *next;
+  Elf32_Addr *addr;
+  Elf32_Addr value;
+};
+#endif
+
 struct arch_file {
        struct obj_file root;
 #if defined(BB_USE_PLT_ENTRIES)
@@ -602,6 +647,9 @@ struct arch_file {
 #if defined(BB_USE_GOT_ENTRIES)
        struct obj_section *got;
 #endif
+#if defined(__mips__)
+       struct mips_hi16 *mips_hi16_list;
+#endif
 };
 
 struct arch_symbol {
@@ -631,20 +679,8 @@ int n_ext_modules;
 int n_ext_modules_used;
 
 
-
-/* Some firendly syscalls to cheer everyone's day...  */
-#define __NR_new_sys_init_module  __NR_init_module
-_syscall2(int, new_sys_init_module, const char *, name,
-                 const struct new_module *, info)
-#define __NR_old_sys_init_module  __NR_init_module
-_syscall5(int, old_sys_init_module, const char *, name, char *, code,
-                 unsigned, codesize, struct old_mod_routines *, routines,
-                 struct old_symbol_table *, symtab)
-#ifndef BB_RMMOD
-_syscall1(int, delete_module, const char *, name)
-#else
 extern int delete_module(const char *);
-#endif
+
 
 /* This is kind of troublesome. See, we don't actually support
    the m68k or the arm the same way we support i386 and (now)
@@ -657,31 +693,8 @@ extern int delete_module(const char *);
 
    -- Bryan Rittmeyer <bryan@ixiacom.com>                    */
 
-#ifdef BB_FEATURE_OLD_MODULE_INTERFACE
-_syscall1(int, get_kernel_syms, struct old_kernel_sym *, ks)
-#endif
-
-#if defined(__i386__) || defined(__m68k__) || defined(__arm__) \
- || defined(__powerpc__)
-/* Jump through hoops to fixup error return codes */
-#define __NR__create_module  __NR_create_module
-static inline _syscall2(long, _create_module, const char *, name, size_t,
-                                               size)
-unsigned long create_module(const char *name, size_t size)
-{
-       long ret = _create_module(name, size);
-
-       if (ret == -1 && errno > 125) {
-               ret = -errno;
-               errno = 0;
-       }
-       return ret;
-}
-#else
-_syscall2(unsigned long, create_module, const char *, name, size_t, size)
-#endif
-static char m_filename[BUFSIZ + 1] = "\0";
-static char m_fullName[BUFSIZ + 1] = "\0";
+static char m_filename[BUFSIZ + 1];
+static char m_fullName[BUFSIZ + 1];
 
 /*======================================================================*/
 
@@ -703,7 +716,7 @@ static int findNamedModule(const char *fileName, struct stat *statbuf,
                        tmp++;
                if (check_wildcard_match(tmp, fullName) == TRUE) {
                        /* Stop searching if we find a match */
-                       memcpy(m_filename, fileName, strlen(fileName)+1);
+                       safe_strncpy(m_filename, fileName, sizeof(m_filename));
                        return (FALSE);
                }
        }
@@ -724,6 +737,9 @@ struct obj_file *arch_new_file(void)
 #if defined(BB_USE_GOT_ENTRIES)
        f->got = NULL;
 #endif
+#if defined(__mips__)
+       f->mips_hi16_list = NULL;
+#endif
 
        return &f->root;
 }
@@ -756,7 +772,9 @@ arch_apply_relocation(struct obj_file *f,
                                      ElfW(RelM) *rel, ElfW(Addr) v)
 {
        struct arch_file *ifile = (struct arch_file *) f;
+#if !(defined(__mips__))
        struct arch_symbol *isym = (struct arch_symbol *) sym;
+#endif
 
        ElfW(Addr) *loc = (ElfW(Addr) *) (targsec->contents + rel->r_offset);
        ElfW(Addr) dot = targsec->header.sh_addr + rel->r_offset;
@@ -783,6 +801,8 @@ arch_apply_relocation(struct obj_file *f,
        case R_386_NONE:
 #elif defined(__powerpc__)
        case R_PPC_NONE:
+#elif defined(__mips__)
+       case R_MIPS_NONE:
 #endif
                break;
 
@@ -794,6 +814,8 @@ arch_apply_relocation(struct obj_file *f,
        case R_386_32:  
 #elif defined(__powerpc__)
        case R_PPC_ADDR32:
+#elif defined(__mips__)
+       case R_MIPS_32:
 #endif
                *loc += v;
                break;
@@ -812,6 +834,86 @@ arch_apply_relocation(struct obj_file *f,
                break;
 #endif
 
+#if defined(__mips__)
+       case R_MIPS_26:
+               if (v % 4)
+                       ret = obj_reloc_dangerous;
+               if ((v & 0xf0000000) != ((dot + 4) & 0xf0000000))
+                       ret = obj_reloc_overflow;
+               *loc =
+                   (*loc & ~0x03ffffff) | ((*loc + (v >> 2)) &
+                                           0x03ffffff);
+               break;
+
+       case R_MIPS_HI16:
+               {
+                       struct mips_hi16 *n;
+
+                       /* We cannot relocate this one now because we don't know the value
+                          of the carry we need to add.  Save the information, and let LO16
+                          do the actual relocation.  */
+                       n = (struct mips_hi16 *) xmalloc(sizeof *n);
+                       n->addr = loc;
+                       n->value = v;
+                       n->next = ifile->mips_hi16_list;
+                       ifile->mips_hi16_list = n;
+                       break;
+               }
+
+       case R_MIPS_LO16:
+               {
+                       unsigned long insnlo = *loc;
+                       Elf32_Addr val, vallo;
+
+                       /* Sign extend the addend we extract from the lo insn.  */
+                       vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
+
+                       if (ifile->mips_hi16_list != NULL) {
+                               struct mips_hi16 *l;
+
+                               l = ifile->mips_hi16_list;
+                               while (l != NULL) {
+                                       struct mips_hi16 *next;
+                                       unsigned long insn;
+
+                                       /* The value for the HI16 had best be the same. */
+                                       assert(v == l->value);
+
+                                       /* Do the HI16 relocation.  Note that we actually don't
+                                          need to know anything about the LO16 itself, except where
+                                          to find the low 16 bits of the addend needed by the LO16.  */
+                                       insn = *l->addr;
+                                       val =
+                                           ((insn & 0xffff) << 16) +
+                                           vallo;
+                                       val += v;
+
+                                       /* Account for the sign extension that will happen in the
+                                          low bits.  */
+                                       val =
+                                           ((val >> 16) +
+                                            ((val & 0x8000) !=
+                                             0)) & 0xffff;
+
+                                       insn = (insn & ~0xffff) | val;
+                                       *l->addr = insn;
+
+                                       next = l->next;
+                                       free(l);
+                                       l = next;
+                               }
+
+                               ifile->mips_hi16_list = NULL;
+                       }
+
+                       /* Ok, we're done with the HI16 relocs.  Now deal with the LO16.  */
+                       val = v + vallo;
+                       insnlo = (insnlo & ~0xffff) | (val & 0xffff);
+                       *loc = insnlo;
+                       break;
+               }
+#endif
+
 #if defined(__arm__)
 #elif defined(__sh__)
         case R_SH_REL32:
@@ -977,6 +1079,7 @@ arch_apply_relocation(struct obj_file *f,
 
 int arch_create_got(struct obj_file *f)
 {
+#if defined(BB_USE_GOT_ENTRIES) || defined(BB_USE_PLT_ENTRIES)
        struct arch_file *ifile = (struct arch_file *) f;
        int i;
 #if defined(BB_USE_GOT_ENTRIES)
@@ -1077,18 +1180,18 @@ int arch_create_got(struct obj_file *f)
 
 #if defined(BB_USE_GOT_ENTRIES)
        if (got_offset) {
-               struct obj_section* relsec = obj_find_section(f, ".got");
+               struct obj_section* myrelsec = obj_find_section(f, ".got");
 
-               if (relsec) {
-                       obj_extend_section(relsec, got_offset);
+               if (myrelsec) {
+                       obj_extend_section(myrelsec, got_offset);
                } else {
-                       relsec = obj_create_alloced_section(f, ".got", 
+                       myrelsec = obj_create_alloced_section(f, ".got", 
                                                            BB_GOT_ENTRY_SIZE,
                                                            got_offset);
-                       assert(relsec);
+                       assert(myrelsec);
                }
 
-               ifile->got = relsec;
+               ifile->got = myrelsec;
        }
 #endif
 
@@ -1097,6 +1200,7 @@ int arch_create_got(struct obj_file *f)
                ifile->plt = obj_create_alloced_section(f, ".plt", 
                                                        BB_PLT_ENTRY_SIZE, 
                                                        plt_offset);
+#endif
 #endif
        return 1;
 }
@@ -1432,7 +1536,9 @@ struct obj_section *obj_create_alloced_section_first(struct obj_file *f,
 void *obj_extend_section(struct obj_section *sec, unsigned long more)
 {
        unsigned long oldsize = sec->header.sh_size;
-       sec->contents = xrealloc(sec->contents, sec->header.sh_size += more);
+       if (more) { 
+               sec->contents = xrealloc(sec->contents, sec->header.sh_size += more);
+       }
        return sec->contents + oldsize;
 }
 
@@ -1614,19 +1720,19 @@ old_process_module_arguments(struct obj_file *f, int argc, char **argv)
                        while (*q++ == ',');
                } else {
                        char *contents = f->sections[sym->secidx]->contents;
-                       char *loc = contents + sym->value;
+                       char *myloc = contents + sym->value;
                        char *r;                        /* To search for commas */
 
                        /* Break the string with comas */
                        while ((r = strchr(q, ',')) != (char *) NULL) {
                                *r++ = '\0';
-                               obj_string_patch(f, sym->secidx, loc - contents, q);
-                               loc += sizeof(char *);
+                               obj_string_patch(f, sym->secidx, myloc - contents, q);
+                               myloc += sizeof(char *);
                                q = r;
                        }
 
                        /* last part */
-                       obj_string_patch(f, sym->secidx, loc - contents, q);
+                       obj_string_patch(f, sym->secidx, myloc - contents, q);
                }
 
                argc--, argv++;
@@ -1683,8 +1789,11 @@ static int old_get_kernel_symbols(const char *m_name)
        int nks, nms, nmod, i;
 
        nks = get_kernel_syms(NULL);
-       if (nks < 0) {
-               perror_msg("get_kernel_syms: %s", m_name);
+       if (nks <= 0) {
+               if (nks)
+                       perror_msg("get_kernel_syms: %s", m_name);
+               else
+                       error_msg("No kernel symbols");
                return 0;
        }
 
@@ -1704,7 +1813,6 @@ static int old_get_kernel_symbols(const char *m_name)
 
        while (k->name[0] == '#' && k->name[1]) {
                struct old_kernel_sym *k2;
-               struct new_module_symbol *s;
 
                /* Find out how many symbols this module has.  */
                for (k2 = k + 1; k2->name[0] != '#'; ++k2)
@@ -2174,7 +2282,7 @@ static int new_get_kernel_symbols(void)
        module_names = xmalloc(bufsize = 256);
   retry_modules_load:
        if (query_module(NULL, QM_MODULES, module_names, bufsize, &ret)) {
-               if (errno == ENOSPC) {
+               if (errno == ENOSPC && bufsize < ret) {
                        module_names = xrealloc(module_names, bufsize = ret);
                        goto retry_modules_load;
                }
@@ -2183,48 +2291,50 @@ static int new_get_kernel_symbols(void)
        }
 
        n_ext_modules = nmod = ret;
-       ext_modules = modules = xmalloc(nmod * sizeof(*modules));
-       memset(modules, 0, nmod * sizeof(*modules));
 
        /* Collect the modules' symbols.  */
 
-       for (i = 0, mn = module_names, m = modules;
-                i < nmod; ++i, ++m, mn += strlen(mn) + 1) {
-               struct new_module_info info;
-
-               if (query_module(mn, QM_INFO, &info, sizeof(info), &ret)) {
-                       if (errno == ENOENT) {
-                               /* The module was removed out from underneath us.  */
-                               continue;
-                       }
-                       perror_msg("query_module: QM_INFO: %s", mn);
-                       return 0;
-               }
-
-               syms = xmalloc(bufsize = 1024);
-         retry_mod_sym_load:
-               if (query_module(mn, QM_SYMBOLS, syms, bufsize, &ret)) {
-                       switch (errno) {
-                       case ENOSPC:
-                               syms = xrealloc(syms, bufsize = ret);
-                               goto retry_mod_sym_load;
-                       case ENOENT:
-                               /* The module was removed out from underneath us.  */
-                               continue;
-                       default:
-                               perror_msg("query_module: QM_SYMBOLS: %s", mn);
+       if (nmod){
+               ext_modules = modules = xmalloc(nmod * sizeof(*modules));
+               memset(modules, 0, nmod * sizeof(*modules));
+               for (i = 0, mn = module_names, m = modules;
+                        i < nmod; ++i, ++m, mn += strlen(mn) + 1) {
+                       struct new_module_info info;
+       
+                       if (query_module(mn, QM_INFO, &info, sizeof(info), &ret)) {
+                               if (errno == ENOENT) {
+                                       /* The module was removed out from underneath us.  */
+                                       continue;
+                               }
+                               perror_msg("query_module: QM_INFO: %s", mn);
                                return 0;
                        }
-               }
-               nsyms = ret;
-
-               m->name = mn;
-               m->addr = info.addr;
-               m->nsyms = nsyms;
-               m->syms = syms;
-
-               for (j = 0, s = syms; j < nsyms; ++j, ++s) {
-                       s->name += (unsigned long) syms;
+       
+                       syms = xmalloc(bufsize = 1024);
+                 retry_mod_sym_load:
+                       if (query_module(mn, QM_SYMBOLS, syms, bufsize, &ret)) {
+                               switch (errno) {
+                               case ENOSPC:
+                                       syms = xrealloc(syms, bufsize = ret);
+                                       goto retry_mod_sym_load;
+                               case ENOENT:
+                                       /* The module was removed out from underneath us.  */
+                                       continue;
+                               default:
+                                       perror_msg("query_module: QM_SYMBOLS: %s", mn);
+                                       return 0;
+                               }
+                       }
+                       nsyms = ret;
+       
+                       m->name = mn;
+                       m->addr = info.addr;
+                       m->nsyms = nsyms;
+                       m->syms = syms;
+       
+                       for (j = 0, s = syms; j < nsyms; ++j, ++s) {
+                               s->name += (unsigned long) syms;
+                       }
                }
        }
 
@@ -2233,7 +2343,7 @@ static int new_get_kernel_symbols(void)
        syms = xmalloc(bufsize = 16 * 1024);
   retry_kern_sym_load:
        if (query_module(NULL, QM_SYMBOLS, syms, bufsize, &ret)) {
-               if (errno == ENOSPC) {
+               if (errno == ENOSPC && bufsize < ret) {
                        syms = xrealloc(syms, bufsize = ret);
                        goto retry_kern_sym_load;
                }
@@ -2366,6 +2476,9 @@ new_init_module(const char *m_name, struct obj_file *f,
        tgt_long m_addr;
 
        sec = obj_find_section(f, ".this");
+       if (!sec || !sec->contents) { 
+               perror_msg_and_die("corrupt module %s?",m_name);
+       }
        module = (struct new_module *) sec->contents;
        m_addr = sec->header.sh_addr;
 
@@ -2772,7 +2885,7 @@ int obj_create_image(struct obj_file *f, char *image)
        for (sec = f->load_order; sec; sec = sec->load_next) {
                char *secimg;
 
-               if (sec->header.sh_size == 0)
+               if (sec->contents == 0 || sec->header.sh_size == 0)
                        continue;
 
                secimg = image + (sec->header.sh_addr - base);
@@ -2857,7 +2970,7 @@ struct obj_file *obj_load(FILE * fp)
                sec->header = section_headers[i];
                sec->idx = i;
 
-               switch (sec->header.sh_type) {
+               if(sec->header.sh_size) switch (sec->header.sh_type) {
                case SHT_NULL:
                case SHT_NOTE:
                case SHT_NOBITS:
@@ -2917,6 +3030,12 @@ struct obj_file *obj_load(FILE * fp)
        for (i = 0; i < shnum; ++i) {
                struct obj_section *sec = f->sections[i];
 
+               /* .modinfo should be contents only but gcc has no attribute for that.
+                * The kernel may have marked .modinfo as ALLOC, ignore this bit.
+                */
+               if (strcmp(sec->name, ".modinfo") == 0)
+                       sec->header.sh_flags &= ~SHF_ALLOC;
+
                if (sec->header.sh_flags & SHF_ALLOC)
                        obj_insert_section_load_order(f, sec);
 
@@ -2940,22 +3059,20 @@ struct obj_file *obj_load(FILE * fp)
 
                                /* Allocate space for a table of local symbols.  */
                                j = f->local_symtab_size = sec->header.sh_info;
-                               f->local_symtab = xmalloc(j *=
-                                                                                 sizeof(struct obj_symbol *));
-                               memset(f->local_symtab, 0, j);
+                               f->local_symtab = xcalloc(j, sizeof(struct obj_symbol *));
 
                                /* Insert all symbols into the hash table.  */
                                for (j = 1, ++sym; j < nsym; ++j, ++sym) {
                                        const char *name;
                                        if (sym->st_name)
                                                name = strtab + sym->st_name;
-               else
+                                       else
                                                name = f->sections[sym->st_shndx]->name;
 
                                        obj_add_symbol(f, name, j, sym->st_info, sym->st_shndx,
                                                                   sym->st_value, sym->st_size);
-               }
-       }
+                               }
+                       }
                        break;
 
                case SHT_RELM:
@@ -2966,6 +3083,10 @@ struct obj_file *obj_load(FILE * fp)
                                return NULL;
                        }
                        break;
+                       /* XXX  Relocation code from modutils-2.3.19 is not here.
+                        * Why?  That's about 20 lines of code from obj/obj_load.c,
+                        * which gets done in a second pass through the sections.
+                        * This BusyBox insmod does similar work in obj_relocate(). */
                }
        }
 
@@ -3058,7 +3179,8 @@ extern int insmod_main( int argc, char **argv)
 
        if (len > 2 && tmp[len - 2] == '.' && tmp[len - 1] == 'o')
                len -= 2;
-       strncpy(m_fullName, tmp, len);
+       memcpy(m_fullName, tmp, len);
+       m_fullName[len]='\0';
        if (*m_name == '\0') {
                strcpy(m_name, m_fullName);
        }
@@ -3080,7 +3202,7 @@ extern int insmod_main( int argc, char **argv)
                } else
                        error_msg_and_die("No module named '%s' found in '%s'", m_fullName, _PATH_MODULES);
        } else
-               memcpy(m_filename, argv[optind], strlen(argv[optind]));
+               safe_strncpy(m_filename, argv[optind], sizeof(m_filename));
 
 
        if ((f = obj_load(fp)) == NULL)