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recognize and execute dynamically linked executables

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. generalize libexec slightly to get some more necessary information
	  from ELF files, e.g. the interpreter
	. execute dynamically linked executables when exec()ed by VFS
	. switch to netbsd variant of elf32.h exclusively, solves some
	  conflicting headers
This commit is contained in:
Ben Gras 2012-04-03 15:52:25 +02:00
parent 927b9ef243
commit 53002f6f6c
21 changed files with 540 additions and 477 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
common/include/sys/Makefile.inc
View file

@ -2,7 +2,7 @@
.PATH: ${MINIXSRCDIR}/common/include/sys
INCS+= elf32.h elf64.h elf_common.h elf_generic.h \
INCS+= elf64.h elf_common.h elf_generic.h \
ioc_block.h ioc_fbd.h ioc_file.h ioc_tape.h ioc_disk.h \
ioc_memory.h ioc_sound.h ioc_tty.h \
kbdio.h mtio.h svrctl.h video.h vm.h procfs.h elf_core.h exec_elf.h \

249
common/include/sys/elf32.h
View file

@ -1,249 +0,0 @@
/*-
* Copyright (c) 1996-1998 John D. Polstra.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _SYS_ELF32_H_
#define _SYS_ELF32_H_ 1
#include <sys/elf_common.h>
/*
* ELF definitions common to all 32-bit architectures.
*/
typedef uint32_t Elf32_Addr;
typedef uint16_t Elf32_Half;
typedef uint32_t Elf32_Off;
typedef int32_t Elf32_Sword;
typedef uint32_t Elf32_Word;
#if defined(__ACK__)
typedef uint32_t Elf32_Lword;
#else
typedef uint64_t Elf32_Lword;
#endif
typedef Elf32_Word Elf32_Hashelt;
/* Non-standard class-dependent datatype used for abstraction. */
typedef Elf32_Word Elf32_Size;
typedef Elf32_Sword Elf32_Ssize;
/*
* ELF header.
*/
typedef struct {
unsigned char e_ident[EI_NIDENT]; /* File identification. */
Elf32_Half e_type; /* File type. */
Elf32_Half e_machine; /* Machine architecture. */
Elf32_Word e_version; /* ELF format version. */
Elf32_Addr e_entry; /* Entry point. */
Elf32_Off e_phoff; /* Program header file offset. */
Elf32_Off e_shoff; /* Section header file offset. */
Elf32_Word e_flags; /* Architecture-specific flags. */
Elf32_Half e_ehsize; /* Size of ELF header in bytes. */
Elf32_Half e_phentsize; /* Size of program header entry. */
Elf32_Half e_phnum; /* Number of program header entries. */
Elf32_Half e_shentsize; /* Size of section header entry. */
Elf32_Half e_shnum; /* Number of section header entries. */
Elf32_Half e_shstrndx; /* Section name strings section. */
} Elf32_Ehdr;
/*
* Section header.
*/
typedef struct {
Elf32_Word sh_name; /* Section name (index into the
section header string table). */
Elf32_Word sh_type; /* Section type. */
Elf32_Word sh_flags; /* Section flags. */
Elf32_Addr sh_addr; /* Address in memory image. */
Elf32_Off sh_offset; /* Offset in file. */
Elf32_Word sh_size; /* Size in bytes. */
Elf32_Word sh_link; /* Index of a related section. */
Elf32_Word sh_info; /* Depends on section type. */
Elf32_Word sh_addralign; /* Alignment in bytes. */
Elf32_Word sh_entsize; /* Size of each entry in section. */
} Elf32_Shdr;
/*
* Program header.
*/
typedef struct {
Elf32_Word p_type; /* Entry type. */
Elf32_Off p_offset; /* File offset of contents. */
Elf32_Addr p_vaddr; /* Virtual address in memory image. */
Elf32_Addr p_paddr; /* Physical address (not used). */
Elf32_Word p_filesz; /* Size of contents in file. */
Elf32_Word p_memsz; /* Size of contents in memory. */
Elf32_Word p_flags; /* Access permission flags. */
Elf32_Word p_align; /* Alignment in memory and file. */
} Elf32_Phdr;
/*
* Dynamic structure. The ".dynamic" section contains an array of them.
*/
typedef struct {
Elf32_Sword d_tag; /* Entry type. */
union {
Elf32_Word d_val; /* Integer value. */
Elf32_Addr d_ptr; /* Address value. */
} d_un;
} Elf32_Dyn;
/*
* Relocation entries.
*/
/* Relocations that don't need an addend field. */
typedef struct {
Elf32_Addr r_offset; /* Location to be relocated. */
Elf32_Word r_info; /* Relocation type and symbol index. */
} Elf32_Rel;
/* Relocations that need an addend field. */
typedef struct {
Elf32_Addr r_offset; /* Location to be relocated. */
Elf32_Word r_info; /* Relocation type and symbol index. */
Elf32_Sword r_addend; /* Addend. */
} Elf32_Rela;
/* Macros for accessing the fields of r_info. */
#define ELF32_R_SYM(info) ((info) >> 8)
#define ELF32_R_TYPE(info) ((unsigned char)(info))
/* Macro for constructing r_info from field values. */
#define ELF32_R_INFO(sym, type) (((sym) << 8) + (unsigned char)(type))
/*
* Note entry header
*/
typedef Elf_Note Elf32_Nhdr;
/*
* Move entry
*/
typedef struct {
Elf32_Lword m_value; /* symbol value */
Elf32_Word m_info; /* size + index */
Elf32_Word m_poffset; /* symbol offset */
Elf32_Half m_repeat; /* repeat count */
Elf32_Half m_stride; /* stride info */
} Elf32_Move;
/*
* The macros compose and decompose values for Move.r_info
*
* sym = ELF32_M_SYM(M.m_info)
* size = ELF32_M_SIZE(M.m_info)
* M.m_info = ELF32_M_INFO(sym, size)
*/
#define ELF32_M_SYM(info) ((info)>>8)
#define ELF32_M_SIZE(info) ((unsigned char)(info))
#define ELF32_M_INFO(sym, size) (((sym)<<8)+(unsigned char)(size))
/*
* Hardware/Software capabilities entry
*/
typedef struct {
Elf32_Word c_tag; /* how to interpret value */
union {
Elf32_Word c_val;
Elf32_Addr c_ptr;
} c_un;
} Elf32_Cap;
/*
* Symbol table entries.
*/
typedef struct {
Elf32_Word st_name; /* String table index of name. */
Elf32_Addr st_value; /* Symbol value. */
Elf32_Word st_size; /* Size of associated object. */
unsigned char st_info; /* Type and binding information. */
unsigned char st_other; /* Reserved (not used). */
Elf32_Half st_shndx; /* Section index of symbol. */
} Elf32_Sym;
/* Macros for accessing the fields of st_info. */
#define ELF32_ST_BIND(info) ((info) >> 4)
#define ELF32_ST_TYPE(info) ((info) & 0xf)
/* Macro for constructing st_info from field values. */
#define ELF32_ST_INFO(bind, type) (((bind) << 4) + ((type) & 0xf))
/* Macro for accessing the fields of st_other. */
#define ELF32_ST_VISIBILITY(oth) ((oth) & 0x3)
/* Structures used by Sun & GNU symbol versioning. */
typedef struct
{
Elf32_Half vd_version;
Elf32_Half vd_flags;
Elf32_Half vd_ndx;
Elf32_Half vd_cnt;
Elf32_Word vd_hash;
Elf32_Word vd_aux;
Elf32_Word vd_next;
} Elf32_Verdef;
typedef struct
{
Elf32_Word vda_name;
Elf32_Word vda_next;
} Elf32_Verdaux;
typedef struct
{
Elf32_Half vn_version;
Elf32_Half vn_cnt;
Elf32_Word vn_file;
Elf32_Word vn_aux;
Elf32_Word vn_next;
} Elf32_Verneed;
typedef struct
{
Elf32_Word vna_hash;
Elf32_Half vna_flags;
Elf32_Half vna_other;
Elf32_Word vna_name;
Elf32_Word vna_next;
} Elf32_Vernaux;
typedef Elf32_Half Elf32_Versym;
typedef struct {
Elf32_Half si_boundto; /* direct bindings - symbol bound to */
Elf32_Half si_flags; /* per symbol flags */
} Elf32_Syminfo;
#endif /* !_SYS_ELF32_H_ */

74
include/arch/i386/include/elf.h
View file

@ -33,84 +33,10 @@
* ELF definitions for the i386 architecture.
*/
#include <sys/elf32.h> /* Definitions common to all 32 bit architectures. */
#if defined(__ELF_WORD_SIZE) && __ELF_WORD_SIZE == 64
#include <sys/elf64.h> /* Definitions common to all 64 bit architectures. */
#endif
#ifndef __ELF_WORD_SIZE
#define __ELF_WORD_SIZE 32 /* Used by <sys/elf_generic.h> */
#endif
#include <sys/elf_generic.h>
#define ELF_ARCH EM_386
#define ELF_MACHINE_OK(x) ((x) == EM_386 || (x) == EM_486)
/*
* Auxiliary vector entries for passing information to the interpreter.
*
* The i386 supplement to the SVR4 ABI specification names this "auxv_t",
* but POSIX lays claim to all symbols ending with "_t".
*/
typedef struct { /* Auxiliary vector entry on initial stack */
int a_type; /* Entry type. */
union {
long a_val; /* Integer value. */
void *a_ptr; /* Address. */
void (*a_fcn)(void); /* Function pointer (not used). */
} a_un;
} Elf32_Auxinfo;
#if __ELF_WORD_SIZE == 64
/* Fake for amd64 loader support */
typedef struct {
int fake;
} Elf64_Auxinfo;
#endif
__ElfType(Auxinfo);
/* Values for a_type. */
#define AT_NULL 0 /* Terminates the vector. */
#define AT_IGNORE 1 /* Ignored entry. */
#define AT_EXECFD 2 /* File descriptor of program to load. */
#define AT_PHDR 3 /* Program header of program already loaded. */
#define AT_PHENT 4 /* Size of each program header entry. */
#define AT_PHNUM 5 /* Number of program header entries. */
#define AT_PAGESZ 6 /* Page size in bytes. */
#define AT_BASE 7 /* Interpreter's base address. */
#define AT_FLAGS 8 /* Flags (unused for i386). */
#define AT_ENTRY 9 /* Where interpreter should transfer control. */
#define AT_NOTELF 10 /* Program is not ELF ?? */
#define AT_UID 11 /* Real uid. */
#define AT_EUID 12 /* Effective uid. */
#define AT_GID 13 /* Real gid. */
#define AT_EGID 14 /* Effective gid. */
#define AT_EXECPATH 15 /* Path to the executable. */
#define AT_CANARY 16 /* Canary for SSP. */
#define AT_CANARYLEN 17 /* Length of the canary. */
#define AT_OSRELDATE 18 /* OSRELDATE. */
#define AT_NCPUS 19 /* Number of CPUs. */
#define AT_PAGESIZES 20 /* Pagesizes. */
#define AT_PAGESIZESLEN 21 /* Number of pagesizes. */
#define AT_COUNT 22 /* Count of defined aux entry types. */
/*
* Relocation types.
*/
#define R_386_COUNT 38 /* Count of defined relocation types. */
/* Define "machine" characteristics */
#define ELF_TARG_CLASS ELFCLASS32
#define ELF_TARG_DATA ELFDATA2LSB
#define ELF_TARG_MACH EM_386
#define ELF_TARG_VER 1
#define ET_DYN_LOAD_ADDR 0x01001000
#endif /* !_MACHINE_ELF_H_ */

8
include/minix/com.h
View file

@ -542,6 +542,12 @@
#define PR_FORK_MSGADDR m1_p1 /* reply message address of forked child */
#define PR_CTX_PTR m1_p1 /* pointer to mcontext_t structure */
/* Field names for EXEC sent from userland to PM. */
#define PMEXEC_FLAGS m1_i3 /* PMEF_* */
#define PMEF_AUXVECTORS 20
#define PMEF_AUXVECTORSPACE 0x01 /* space for PMEF_AUXVECTORS on stack */
/* Flags for PR_FORK_FLAGS. */
#define PFF_VMINHIBIT 0x01 /* Don't schedule until release by VM. */
@ -797,10 +803,12 @@
*/
# define PM_FRAME m7_p2 /* arguments and environment */
# define PM_FRAME_LEN m7_i3 /* size of frame */
# define PM_EXECFLAGS m7_i4 /* PMEXEC_FLAGS */
/* Additional parameters for PM_EXEC_REPLY and PM_CORE_REPLY */
# define PM_STATUS m7_i2 /* OK or failure */
# define PM_PC m7_p1 /* program counter */
# define PM_NEWSP m7_p2 /* possibly-changed stack ptr */
/* Additional parameters for PM_FORK and PM_SRV_FORK */
# define PM_PPROC m7_i2 /* parent process endpoint */

4
include/sys/Makefile
View file

@ -47,9 +47,7 @@ INCSYMLINKS=\
sys/sha1.h ${NETBSDINCSDIR}/sha1.h \
sys/sha2.h ${NETBSDINCSDIR}/sha2.h \
sys/md4.h ${NETBSDINCSDIR}/md4.h \
sys/md5.h ${NETBSDINCSDIR}/md5.h \
sys/exec_elf.h ${NETBSDINCSDIR}/elf.h \
sys/md5.h ${NETBSDINCSDIR}/md5.h
#INCSYMLINKS+= ../soundcard.h ${INCSDIR}/soundcard.h

2
kernel/arch/i386/pre_init.c
View file

@ -369,6 +369,7 @@ static void mb_extract_image(multiboot_info_t mbi)
/* Save memory map for kernel tasks */
r = read_header_elf((const char *)MULTIBOOT_KERNEL_ADDR,
4096, /* everything is there */
&text_vaddr, &text_paddr,
&text_filebytes, &text_membytes,
&data_vaddr, &data_paddr,
@ -401,6 +402,7 @@ static void mb_extract_image(multiboot_info_t mbi)
/* Load boot image services into memory and save memory map */
for (i = 0; module < &mb_module_info[mods_count]; ++module, ++i) {
r = read_header_elf((const char *)module->mod_start,
module->mod_end - module->mod_start + 1,
&text_vaddr, &text_paddr,
&text_filebytes, &text_membytes,
&data_vaddr, &data_paddr,

21
lib/libc/sys-minix/execve.c
View file

@ -10,6 +10,7 @@
#include <unistd.h>
#include <string.h>
#include <stddef.h>
#include <sys/exec_elf.h>
#ifdef __weak_alias
__weak_alias(execve, _execve)
@ -23,6 +24,7 @@ int execve(const char *path, char * const *argv, char * const *envp)
char **vp;
char *sp;
size_t argc;
int vectors;
size_t frame_size;
size_t string_off;
size_t n;
@ -55,9 +57,14 @@ int execve(const char *path, char * const *argv, char * const *envp)
string_off+= sizeof(*ap);
}
/* Add an argument count and two terminating nulls. */
frame_size+= sizeof(argc) + sizeof(*ap) + sizeof(*ep);
string_off+= sizeof(argc) + sizeof(*ap) + sizeof(*ep);
/* Add an argument count, two terminating nulls and
* space for the ELF aux vectors, that must come before
* (i.e. at a higher address) then the strings.
*/
vectors = sizeof(argc) + sizeof(*ap) + sizeof(*ep) +
sizeof(AuxInfo) * PMEF_AUXVECTORS;
frame_size+= vectors;
string_off+= vectors;
/* Align. */
frame_size= (frame_size + sizeof(char *) - 1) & ~(sizeof(char *) - 1);
@ -100,15 +107,17 @@ int execve(const char *path, char * const *argv, char * const *envp)
/* Padding. */
while (sp < frame + frame_size) *sp++= 0;
/* Clear unused message fields */
memset(&m, 0, sizeof(m));
/* We can finally make the system call. */
m.m1_i1 = strlen(path) + 1;
m.m1_i2 = frame_size;
m.m1_p1 = (char *) __UNCONST(path);
m.m1_p2 = frame;
/* Clear unused fields */
m.m1_i3 = 0;
m.m1_p3 = NULL;
/* Tell PM/VFS we have left space for the aux vectors */
m.PMEXEC_FLAGS = PMEF_AUXVECTORSPACE;
(void) _syscall(PM_PROC_NR, EXEC, &m);

154
lib/libexec/exec_elf.c
View file

@ -7,6 +7,8 @@
#include <unistd.h>
#include <errno.h>
#include <libexec.h>
#include <string.h>
#include <machine/elf.h>
/* For verbose logging */
#define ELF_DEBUG 0
@ -16,10 +18,63 @@
#define SECTOR_SIZE 512
static int __elfN(check_header)(const Elf_Ehdr *hdr);
static int check_header(const Elf_Ehdr *hdr);
static int elf_sane(const Elf_Ehdr *hdr)
{
if (check_header(hdr) != OK) {
return 0;
}
if((hdr->e_type != ET_EXEC) && (hdr->e_type != ET_DYN)) {
return 0;
}
if ((hdr->e_phoff > SECTOR_SIZE) ||
(hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > SECTOR_SIZE) {
#if ELF_DEBUG
printf("peculiar phoff\n");
#endif
return 0;
}
return 1;
}
static int elf_ph_sane(const Elf_Phdr *phdr)
{
if (rounddown((uintptr_t)phdr, sizeof(Elf_Addr)) != (uintptr_t)phdr) {
return 0;
}
return 1;
}
static int elf_unpack(const char *exec_hdr,
int hdr_len, const Elf_Ehdr **hdr, const Elf_Phdr **phdr)
{
*hdr = (const Elf_Ehdr *)exec_hdr;
if(!elf_sane(*hdr)) {
#if ELF_DEBUG
printf("elf_sane failed\n");
#endif
return ENOEXEC;
}
*phdr = (const Elf_Phdr *)(exec_hdr + (*hdr)->e_phoff);
if(!elf_ph_sane(*phdr)) {
#if ELF_DEBUG
printf("elf_ph_sane failed\n");
#endif
return ENOEXEC;
}
#if 0
if((int)((*phdr) + (*hdr)->e_phnum) >= hdr_len) return ENOEXEC;
#endif
return OK;
}
int read_header_elf(
const char *exec_hdr, /* executable header */
int hdr_len, /* significant bytes in exec_hdr */
vir_bytes *text_vaddr, /* text virtual address */
phys_bytes *text_paddr, /* text physical address */
vir_bytes *text_filebytes, /* text segment size (in the file) */
@ -36,7 +91,7 @@ int read_header_elf(
const Elf_Ehdr *hdr = NULL;
const Elf_Phdr *phdr = NULL;
unsigned long seg_filebytes, seg_membytes;
int i = 0;
int e, i = 0;
*text_vaddr = *text_paddr = 0;
*text_filebytes = *text_membytes = 0;
@ -44,27 +99,12 @@ int read_header_elf(
*data_filebytes = *data_membytes = 0;
*pc = *text_offset = *data_offset = 0;
hdr = (const Elf_Ehdr *)exec_hdr;
if (__elfN(check_header)(hdr) != OK || (hdr->e_type != ET_EXEC))
{
return ENOEXEC;
}
if ((hdr->e_phoff > SECTOR_SIZE) ||
(hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > SECTOR_SIZE) {
return ENOEXEC;
}
phdr = (const Elf_Phdr *)(exec_hdr + hdr->e_phoff);
if (
#ifdef __NBSD_LIBC
rounddown((uintptr_t)phdr, sizeof(Elf_Addr)) != (uintptr_t)phdr
#else
!_minix_aligned(hdr->e_phoff, Elf_Addr)
if((e=elf_unpack(exec_hdr, hdr_len, &hdr, &phdr)) != OK) {
#if ELF_DEBUG
printf("elf_unpack failed\n");
#endif
) {
return ENOEXEC;
}
return e;
}
#if ELF_DEBUG
printf("Program header file offset (phoff): %ld\n", hdr->e_phoff);
@ -124,7 +164,12 @@ int read_header_elf(
return OK;
}
static int __elfN(check_header)(const Elf_Ehdr *hdr)
#define IS_ELF(ehdr) ((ehdr).e_ident[EI_MAG0] == ELFMAG0 && \
(ehdr).e_ident[EI_MAG1] == ELFMAG1 && \
(ehdr).e_ident[EI_MAG2] == ELFMAG2 && \
(ehdr).e_ident[EI_MAG3] == ELFMAG3)
static int check_header(const Elf_Ehdr *hdr)
{
if (!IS_ELF(*hdr) ||
hdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
@ -135,3 +180,66 @@ static int __elfN(check_header)(const Elf_Ehdr *hdr)
return OK;
}
int elf_phdr(const char *exec_hdr, int hdr_len, vir_bytes *ret_phdr)
{
const Elf_Ehdr *hdr = NULL;
const Elf_Phdr *phdr = NULL;
int e, i, have_computed_phdr = 1;
if((e=elf_unpack(exec_hdr, hdr_len, &hdr, &phdr)) != OK) return e;
for (i = 0; i < hdr->e_phnum; i++) {
switch (phdr[i].p_type) {
case PT_LOAD:
/* compute phdr based on this heuristic, to be used
* if there is no PT_PHDR
*/
if(phdr[i].p_offset == 0) {
*ret_phdr = phdr[i].p_vaddr + hdr->e_phoff;
have_computed_phdr = 1;
}
break;
case PT_PHDR:
*ret_phdr = phdr[i].p_vaddr;
return OK;
default:
break;;
}
}
if(have_computed_phdr) return OK;
return ENOENT;
}
/* Return >0 if there is an ELF interpreter (i.e. it is a dynamically linked
* executable) and we could extract it successfully.
* Return 0 if there isn't one.
* Return <0 on error.
*/
int elf_has_interpreter(const char *exec_hdr, /* executable header */
int hdr_len, char *interp, int maxsz)
{
const Elf_Ehdr *hdr = NULL;
const Elf_Phdr *phdr = NULL;
int e, i;
if((e=elf_unpack(exec_hdr, hdr_len, &hdr, &phdr)) != OK) return e;
for (i = 0; i < hdr->e_phnum; i++) {
switch (phdr[i].p_type) {
case PT_INTERP:
if(!interp) return 1;
if(phdr[i].p_filesz >= maxsz)
return -1;
if(phdr[i].p_offset + phdr[i].p_filesz >= hdr_len)
return -1;
memcpy(interp, exec_hdr + phdr[i].p_offset, phdr[i].p_filesz);
interp[phdr[i].p_filesz] = '\0';
return 1;
default:
continue;
}
}
return 0;
}

7
lib/libexec/libexec.h
View file

@ -1,7 +1,7 @@
#ifndef _LIBEXEC_H_
#define _LIBEXEC_H_ 1
#include <machine/elf.h>
#include <sys/exec_elf.h>
/* a.out routines */
int read_header_aout(const char *exec_hdr, size_t exec_len, int *sep_id,
@ -10,11 +10,14 @@ int read_header_aout(const char *exec_hdr, size_t exec_len, int *sep_id,
int *hdrlenp);
/* ELF routines */
int read_header_elf(const char *exec_hdr,
int read_header_elf(const char *exec_hdr, int hdr_len,
vir_bytes *text_vaddr, phys_bytes *text_paddr,
vir_bytes *text_filebytes, vir_bytes *text_membytes,
vir_bytes *data_vaddr, phys_bytes *data_paddr,
vir_bytes *data_filebytes, vir_bytes *data_membytes,
vir_bytes *pc, off_t *text_offset, off_t *data_offset);
int elf_has_interpreter(const char *exec_hdr, int hdr_len, char *interp, int maxsz);
int elf_phdr(const char *exec_hdr, int hdr_len, vir_bytes *phdr);
#endif /* !_LIBEXEC_H_ */

4
libexec/ld.elf_so/Makefile
View file

@ -38,7 +38,11 @@ M= ${.CURDIR}/arch/${ARCHSUBDIR}
(${MACHINE_ARCH} == "vax")) && \
${MKPIC} != "no"
.if ${CC} == "gcc"
LDFLAGS+= -shared -symbolic -nostartfiles
.else
LDFLAGS+= -shared -Wl,-Bsymbolic -nostartfiles
.endif
LDFLAGS+= -Wl,-static
LDFLAGS+= -Wl,--warn-shared-textrel

54
libexec/ld.elf_so/map_object.c
View file

@ -53,6 +53,53 @@ static int protflags(int); /* Elf flags -> mmap protection */
#define EA_UNDEF (~(Elf_Addr)0)
#ifdef __minix
#define mmap minix_mmap_emulator
#define munmap minix_munmap
/* for minix, ignore MAP_SHARED and MAP_FILE for now. */
#define MAP_SHARED 0
#define MAP_FILE 0
#endif
#undef MINIXVERBOSE
static void * minix_mmap_emulator(void *addrhint, size_t size, int prot, int flags, int fd, off_t off)
{
void *ret;
int mapflags;
size_t s;
mapflags = flags & (MAP_FIXED);
#ifdef MINIXVERBOSE
if(addrhint) {
fprintf(stderr, "0x%lx-0x%lx requested\n", addrhint,
(char *) addrhint + size);
}
#endif
if((ret = minix_mmap(addrhint, size, PROT_READ|PROT_WRITE,
MAP_ANON|MAP_PRIVATE|MAP_PREALLOC|mapflags, -1, 0)) == MAP_FAILED) {
return ret;
}
if(!(mapflags & MAP_ANON)) {
if((s=pread(fd, ret, size, off)) <= 0) {
munmap(ret, size);
return MAP_FAILED;
}
}
#ifdef MINIXVERBOSE
fprintf(stderr, "0x%lx-0x%lx mapped\n",
ret, (char *) ret + size);
#endif
return ret;
}
/*
* Map a shared object into memory. The argument is a file descriptor,
* which must be open on the object and positioned at its beginning.
@ -296,8 +343,15 @@ _rtld_map_object(const char *path, int fd, const struct stat *sb)
base_addr = NULL;
#endif
mapsize = base_vlimit - base_vaddr;
#ifndef __minix
mapbase = mmap(base_addr, mapsize, text_flags,
mapflags | MAP_FILE | MAP_PRIVATE, fd, base_offset);
#else
/* minix doesn't want overlapping mmap()s */
mapbase = mmap(base_addr, obj->textsize, text_flags,
mapflags | MAP_FILE | MAP_PRIVATE, fd, base_offset);
#endif
if (mapbase == MAP_FAILED) {
_rtld_error("mmap of entire address space failed: %s",
xstrerror(errno));

11
servers/pm/exec.c
View file

@ -47,6 +47,7 @@ int do_exec()
m.PM_PATH_LEN = m_in.exec_len;
m.PM_FRAME = m_in.frame_ptr;
m.PM_FRAME_LEN = m_in.frame_len;
m.PM_EXECFLAGS = m_in.PMEXEC_FLAGS;
tell_vfs(mp, &m);
@ -148,7 +149,7 @@ int do_execrestart()
result= m_in.EXC_RS_RESULT;
pc= (vir_bytes)m_in.EXC_RS_PC;
exec_restart(rmp, result, pc);
exec_restart(rmp, result, pc, rmp->mp_frame_addr);
return OK;
}
@ -157,13 +158,13 @@ int do_execrestart()
/*===========================================================================*
* exec_restart *
*===========================================================================*/
void exec_restart(rmp, result, pc)
void exec_restart(rmp, result, pc, vfs_newsp)
struct mproc *rmp;
int result;
vir_bytes pc;
vir_bytes vfs_newsp;
{
int r, sn;
char *new_sp;
if (result != OK)
{
@ -202,8 +203,8 @@ vir_bytes pc;
}
#endif /* USE_TRACE */
new_sp= (char *)rmp->mp_frame_addr;
r= sys_exec(rmp->mp_endpoint, new_sp, rmp->mp_name, pc);
/* Call kernel to exec with SP and PC set by VFS. */
r= sys_exec(rmp->mp_endpoint, (char *) vfs_newsp, rmp->mp_name, pc);
if (r != OK) panic("sys_exec failed: %d", r);
}

3
servers/pm/main.c
View file

@ -447,7 +447,8 @@ static void handle_vfs_reply()
break;
case PM_EXEC_REPLY:
exec_restart(rmp, m_in.PM_STATUS, (vir_bytes)m_in.PM_PC);
exec_restart(rmp, m_in.PM_STATUS, (vir_bytes)m_in.PM_PC,
(vir_bytes)m_in.PM_NEWSP);
break;

2
servers/pm/proto.h
View file

@ -20,7 +20,7 @@ int do_brk(void);
int do_exec(void);
int do_exec_newmem(void);
int do_execrestart(void);
void exec_restart(struct mproc *rmp, int result, vir_bytes pc);
void exec_restart(struct mproc *rmp, int result, vir_bytes pc, vir_bytes sp);
/* forkexit.c */
int do_fork(void);

7
servers/rs/exec.c
View file

@ -253,7 +253,7 @@ static int load_elf(struct exec_info *execi)
proc_e = execi->proc_e;
/* Read the file header and extract the segment sizes. */
r = read_header_elf(execi->image, &text_vaddr, &text_paddr,
r = read_header_elf(execi->image, execi->image_len, &text_vaddr, &text_paddr,
&text_filebytes, &text_membytes,
&data_vaddr, &data_paddr,
&data_filebytes, &data_membytes,
@ -262,6 +262,11 @@ static int load_elf(struct exec_info *execi)
return(r);
}
if(elf_has_interpreter(execi->image, execi->image_len, NULL, 0)) {
printf("RS: can't execute dynamically linked executables\n");
return ENOEXEC;
}
new_uid= getuid();
new_gid= getgid();
allow_setuid = 0;

3
servers/vfs/coredump.c
View file

@ -4,11 +4,12 @@
#include "fproc.h"
#include <minix/vm.h>
#include <sys/mman.h>
#include <machine/elf.h>
#include <sys/exec_elf.h>
#include "param.h"
/* Include ELF headers */
#include <sys/elf_core.h>
#include <machine/elf.h>
static void fill_elf_header(Elf32_Ehdr *elf_header, int phnum);
static void fill_prog_header(Elf32_Phdr *prog_header, Elf32_Word

393
servers/vfs/exec.c
View file

@ -31,10 +31,14 @@
#include "param.h"
#include "vnode.h"
#include <minix/vfsif.h>
#include <machine/vmparam.h>
#include <assert.h>
#include <libexec.h>
#include <fcntl.h>
#include "exec.h"
#define _KERNEL /* for ELF_AUX_ENTRIES */
#include <libexec.h>
static void lock_exec(void);
static void unlock_exec(void);
static int exec_newmem(int proc_e, vir_bytes text_addr, vir_bytes text_bytes,
@ -42,9 +46,9 @@ static int exec_newmem(int proc_e, vir_bytes text_addr, vir_bytes text_bytes,
vir_bytes frame_len, int sep_id, int is_elf, dev_t st_dev,
ino_t st_ino, time_t ctime, char *progname, int new_uid, int new_gid,
vir_bytes *stack_topp, int *load_textp, int *setugidp);
static int is_script(const char *exec_hdr, size_t exec_len);
static int patch_stack(struct vnode *vp, char stack[ARG_MAX],
size_t *stk_bytes, char path[PATH_MAX]);
static int is_script(struct exec_info *execi);
static int insert_arg(char stack[ARG_MAX], size_t *stk_bytes, char *arg,
int replace);
static void patch_ptr(char stack[ARG_MAX], vir_bytes base);
@ -53,23 +57,27 @@ static int read_seg(struct vnode *vp, off_t off, int proc_e, int seg,
vir_bytes seg_addr, phys_bytes seg_bytes);
static int load_aout(struct exec_info *execi);
static int load_elf(struct exec_info *execi);
static int map_header(char **exec_hdr, const struct vnode *vp);
static int stack_prepare_elf(struct exec_info *execi,
char *curstack, size_t *frame_len, int *extrabase);
static int map_header(struct exec_info *execi);
#define PTRSIZE sizeof(char *) /* Size of pointers in argv[] and envp[]. */
/* Array of loaders for different object file formats */
typedef int (*exechook_t)(struct exec_info *execpackage);
typedef int (*stackhook_t)(struct exec_info *execi, char *curstack,
size_t *frame_len, int *extrabase);
struct exec_loaders {
int (*load_object)(struct exec_info *);
exechook_t load_object; /* load executable into memory */
stackhook_t setup_stack; /* prepare stack before argc and argv push */
};
static const struct exec_loaders exec_loaders[] = {
{ load_aout },
{ load_elf },
{ NULL }
{ load_aout, NULL },
{ load_elf, stack_prepare_elf },
{ NULL, NULL }
};
static char hdr[PAGE_SIZE]; /* Assume that header is not larger than a page */
/*===========================================================================*
* lock_exec *
*===========================================================================*/
@ -101,112 +109,186 @@ static void unlock_exec(void)
panic("Could not release lock on exec");
}
/*===========================================================================*
* get_read_vp *
*===========================================================================*/
static int get_read_vp(struct exec_info *execi, char *fullpath,
int copyprogname, int sugid, struct lookup *resolve, struct fproc *fp)
{
/* Make the executable that we want to exec() into the binary pointed
* to by 'fullpath.' This function fills in necessary details in the execi
* structure, such as opened vnode. It unlocks and releases the vnode if
* it was already there. This makes it easy to change the executable
* during the exec(), which is often necessary, by calling this function
* more than once. This is specifically necessary when we discover the
* executable is actually a script or a dynamically linked executable.
*/
int r;
/* Caller wants to switch vp to the file in 'fullpath.'
* unlock and put it first if there is any there.
*/
if(execi->vp) {
unlock_vnode(execi->vp);
put_vnode(execi->vp);
execi->vp = NULL;
}
/* Remember/overwrite the executable name if requested. */
if(copyprogname) {
char *cp = strrchr(fullpath, '/');
if(cp) cp++;
else cp = fullpath;
strncpy(execi->progname, cp, sizeof(execi->progname)-1);
execi->progname[sizeof(execi->progname)-1] = '\0';
}
/* Open executable */
if ((execi->vp = eat_path(resolve, fp)) == NULL)
return err_code;
unlock_vmnt(execi->vmp);
if ((execi->vp->v_mode & I_TYPE) != I_REGULAR)
return ENOEXEC;
else if ((r = forbidden(fp, execi->vp, X_BIT)) != OK)
return r;
else
r = req_stat(execi->vp->v_fs_e, execi->vp->v_inode_nr,
VFS_PROC_NR, (vir_bytes) &(execi->sb), 0, 0);
if (r != OK) return r;
/* If caller wants us to, honour suid/guid mode bits. */
if (sugid) {
/* Deal with setuid/setgid executables */
if (execi->vp->v_mode & I_SET_UID_BIT) {
execi->new_uid = execi->vp->v_uid;
execi->setugid = 1;
}
if (execi->vp->v_mode & I_SET_GID_BIT) {
execi->new_gid = execi->vp->v_gid;
execi->setugid = 1;
}
}
/* Read in first chunk of file. */
if((r=map_header(execi)) != OK)
return r;
return OK;
}
#define FAILCHECK(expr) if((r=(expr)) != OK) { goto pm_execfinal; } while(0)
#define Get_read_vp(e,f,p,s,rs,fp) do { \
r=get_read_vp(&e,f,p,s,rs,fp); if(r != OK) { FAILCHECK(r); } \
} while(0)
/*===========================================================================*
* pm_exec *
*===========================================================================*/
int pm_exec(endpoint_t proc_e, vir_bytes path, size_t path_len,
vir_bytes frame, size_t frame_len, vir_bytes *pc)
vir_bytes frame, size_t frame_len, vir_bytes *pc,
vir_bytes *newsp, int user_exec_flags)
{
/* Perform the execve(name, argv, envp) call. The user library builds a
* complete stack image, including pointers, args, environ, etc. The stack
* is copied to a buffer inside VFS, and then to the new core image.
*/
int r, r1, round, slot;
int r, slot;
vir_bytes vsp;
struct fproc *rfp;
struct vnode *vp;
struct vmnt *vmp;
char *cp;
int extrabase = 0;
static char mbuf[ARG_MAX]; /* buffer for stack and zeroes */
struct exec_info execi;
int i;
char fullpath[PATH_MAX];
static char fullpath[PATH_MAX],
elf_interpreter[PATH_MAX],
finalexec[PATH_MAX];
struct lookup resolve;
stackhook_t makestack = NULL;
lock_exec();
/* unset execi values are 0. */
memset(&execi, 0, sizeof(execi));
/* passed from exec() libc code */
execi.userflags = user_exec_flags;
okendpt(proc_e, &slot);
rfp = fp = &fproc[slot];
vp = NULL;
lookup_init(&resolve, fullpath, PATH_NOFLAGS, &vmp, &vp);
lookup_init(&resolve, fullpath, PATH_NOFLAGS, &execi.vmp, &execi.vp);
resolve.l_vmnt_lock = VMNT_READ;
resolve.l_vnode_lock = VNODE_READ;
/* Get the exec file name. */
if ((r = fetch_name(path, path_len, fullpath)) != OK)
goto pm_execfinal;
/* Fetch the stack from the user before destroying the old core image. */
if (frame_len > ARG_MAX) {
r = ENOMEM; /* stack too big */
goto pm_execfinal;
}
if (frame_len > ARG_MAX)
FAILCHECK(ENOMEM); /* stack too big */
r = sys_datacopy(proc_e, (vir_bytes) frame, SELF, (vir_bytes) mbuf,
(size_t) frame_len);
if (r != OK) { /* can't fetch stack (e.g. bad virtual addr) */
printf("VFS: pm_exec: sys_datacopy failed\n");
goto pm_execfinal;
FAILCHECK(r);
}
/* The default is to keep the original user and group IDs */
execi.new_uid = rfp->fp_effuid;
execi.new_gid = rfp->fp_effgid;
for (round = 0; round < 2; round++) {
/* round = 0 (first attempt), or 1 (interpreted script) */
/* Save the name of the program */
(cp = strrchr(fullpath, '/')) ? cp++ : (cp = fullpath);
/* Get the exec file name. */
FAILCHECK(fetch_name(path, path_len, fullpath));
strcpy(finalexec, fullpath);
strncpy(execi.progname, cp, PROC_NAME_LEN-1);
execi.progname[PROC_NAME_LEN-1] = '\0';
execi.setugid = 0;
/* Get_read_vp will return an opened vn in execi.
* if necessary it releases the existing vp so we can
* switch after we find out what's inside the file.
* It reads the start of the file.
*/
Get_read_vp(execi, fullpath, 1, 1, &resolve, fp);
/* Open executable */
if ((vp = eat_path(&resolve, fp)) == NULL) {
r = err_code;
goto pm_execfinal;
/* If this is a script (i.e. has a #!/interpreter line),
* retrieve the name of the interpreter and open that
* executable instead.
*/
if(is_script(&execi)) {
/* patch_stack will add interpreter name and
* args to stack and retrieve the new binary
* name into fullpath.
*/
FAILCHECK(fetch_name(path, path_len, fullpath));
FAILCHECK(patch_stack(execi.vp, mbuf, &frame_len, fullpath));
strcpy(finalexec, fullpath);
Get_read_vp(execi, fullpath, 1, 0, &resolve, fp);
}
/* If this is a dynamically linked executable, retrieve
* the name of that interpreter in elf_interpreter and open that
* executable instead. But open the current executable in an
* fd for the current process.
*/
if(elf_has_interpreter(execi.hdr, execi.hdr_len,
elf_interpreter, sizeof(elf_interpreter))) {
/* Switch the executable vnode to the interpreter */
execi.is_dyn = 1;
/* The interpreter (loader) needs an fd to the main program,
* which is currently in finalexec
*/
if((r = execi.elf_main_fd = common_open(finalexec, O_RDONLY, 0)) < 0) {
printf("VFS: exec: dynamic: open main exec failed %s (%d)\n",
fullpath, r);
FAILCHECK(r);
}
execi.vp = vp;
unlock_vmnt(vmp);
if ((vp->v_mode & I_TYPE) != I_REGULAR)
r = ENOEXEC;
else if ((r1 = forbidden(fp, vp, X_BIT)) != OK)
r = r1;
else
r = req_stat(vp->v_fs_e, vp->v_inode_nr, VFS_PROC_NR,
(vir_bytes) &(execi.sb), 0, 0);
if (r != OK) goto pm_execfinal;
if (round == 0) {
/* Deal with setuid/setgid executables */
if (vp->v_mode & I_SET_UID_BIT) {
execi.new_uid = vp->v_uid;
execi.setugid = 1;
}
if (vp->v_mode & I_SET_GID_BIT) {
execi.new_gid = vp->v_gid;
execi.setugid = 1;
}
}
r = map_header(&execi.hdr, execi.vp);
if (r != OK) goto pm_execfinal;
if (!is_script(execi.hdr, execi.vp->v_size) || round != 0)
break;
/* Get fresh copy of the file name. */
if ((r = fetch_name(path, path_len, fullpath)) != OK)
printf("VFS pm_exec: 2nd fetch_name failed\n");
else
r = patch_stack(vp, mbuf, &frame_len, fullpath);
unlock_vnode(vp);
put_vnode(vp);
vp = NULL;
if (r != OK) goto pm_execfinal;
/* The executable we need to execute first (loader)
* is in elf_interpreter, and has to be in fullpath to
* be looked up
*/
strcpy(fullpath, elf_interpreter);
Get_read_vp(execi, fullpath, 0, 0, &resolve, fp);
}
execi.proc_e = proc_e;
@ -215,28 +297,27 @@ int pm_exec(endpoint_t proc_e, vir_bytes path, size_t path_len,
for (i = 0; exec_loaders[i].load_object != NULL; i++) {
r = (*exec_loaders[i].load_object)(&execi);
/* Loaded successfully, so no need to try other loaders */
if (r == OK) break;
if (r == OK) { makestack = exec_loaders[i].setup_stack; break; }
}
if (r != OK) { /* No exec loader could load the object */
r = ENOEXEC;
goto pm_execfinal;
}
FAILCHECK(r);
/* Save off PC */
*pc = execi.pc;
/* Patch up stack and copy it from VFS to new core image. */
/* call a stack-setup function if this executable type wants it */
vsp = execi.stack_top;
vsp -= frame_len;
patch_ptr(mbuf, vsp);
if ((r = sys_datacopy(SELF, (vir_bytes) mbuf, proc_e, (vir_bytes) vsp,
(phys_bytes)frame_len)) != OK) {
printf("VFS: datacopy failed (%d) trying to copy to %lu\n", r, vsp);
goto pm_execfinal;
}
if(makestack) FAILCHECK(makestack(&execi, mbuf, &frame_len, &extrabase));
/* Patch up stack and copy it from VFS to new core image. */
vsp -= frame_len;
patch_ptr(mbuf, vsp + extrabase);
FAILCHECK(sys_datacopy(SELF, (vir_bytes) mbuf, proc_e, (vir_bytes) vsp,
(phys_bytes)frame_len));
/* Return new stack pointer to caller */
*newsp = vsp;
if (r != OK) goto pm_execfinal;
clo_exec(rfp);
if (execi.setugid) {
@ -246,10 +327,13 @@ int pm_exec(endpoint_t proc_e, vir_bytes path, size_t path_len,
rfp->fp_effgid = execi.new_gid;
}
/* Remember the new name of the process */
strcpy(rfp->fp_name, execi.progname);
pm_execfinal:
if (vp != NULL) {
unlock_vnode(vp);
put_vnode(vp);
if (execi.vp != NULL) {
unlock_vnode(execi.vp);
put_vnode(execi.vp);
}
unlock_exec();
return(r);
@ -306,6 +390,79 @@ static int load_aout(struct exec_info *execi)
return(r);
}
static int stack_prepare_elf(struct exec_info *execi, char *frame, size_t *framelen, int *extrabase)
{
AuxInfo *a;
Elf_Ehdr *elf_header;
int nulls;
char **mysp = (char **) frame,
**mysp_end = (char **) ((char *)frame + *framelen);
if(!execi->is_dyn)
return OK;
assert(execi->hdr_len >= sizeof(*elf_header));
elf_header = (Elf_Ehdr *) execi->hdr;
/* exec() promises stack space. Now find it. */
mysp++; /* skip argc */
/* find a terminating NULL entry twice: one for argv[], one for envp[]. */
for(nulls = 0; nulls < 2; nulls++) {
assert(mysp < mysp_end);
while(*mysp && mysp < mysp_end) mysp++; /* find terminating NULL */
if(mysp >= mysp_end) {
printf("VFS: malformed stack for exec()\n");
return ENOEXEC;
}
assert(!*mysp);
mysp++;
}
/* Userland provides a fully filled stack frame, with argc, argv, envp
* and then all the argv and envp strings; consistent with ELF ABI, except
* for a list of Aux vectors that should be between envp points and the
* start of the strings.
*
* It would take some very unpleasant hackery to insert the aux vectors before
* the strings, and correct all the pointers, so the exec code in libc makes
* space for us first and indicates the fact it did this with this flag.
*/
if(!(execi->userflags & PMEF_AUXVECTORSPACE)) {
char *f = (char *) mysp;
int remain;
vir_bytes extrabytes = sizeof(*a) * PMEF_AUXVECTORS;
/* Create extrabytes more space */
remain = *framelen - (int)(f - frame);
if(*framelen + extrabytes >= ARG_MAX)
return ENOMEM;
*framelen += extrabytes;
*extrabase += extrabytes;
memmove(f+extrabytes, f, remain);
memset(f, 0, extrabytes);
}
/* Ok, what mysp points to now we can use for the aux vectors. */
a = (AuxInfo *) mysp;
#define AUXINFO(type, value) \
{ assert((char *) a < (char *) mysp_end); a->a_type = type; a->a_v = value; a++; }
#if 0
AUXINFO(AT_PHDR, execi->elf_phdr);
AUXINFO(AT_PHENT, elf_header->e_phentsize);
AUXINFO(AT_PHNUM, elf_header->e_phnum);
#endif
AUXINFO(AT_BASE, execi->elf_base);
AUXINFO(AT_ENTRY, execi->pc);
AUXINFO(AT_PAGESZ, PAGE_SIZE);
AUXINFO(AT_EXECFD, execi->elf_main_fd);
/* Always terminate with AT_NULL */
AUXINFO(AT_NULL, 0);
return OK;
}
/*===========================================================================*
* load_elf *
*===========================================================================*/
@ -318,7 +475,8 @@ static int load_elf(struct exec_info *execi)
vir_bytes text_vaddr, text_paddr, text_filebytes, text_membytes;
vir_bytes data_vaddr, data_paddr, data_filebytes, data_membytes;
off_t text_offset, data_offset;
int sep_id, is_elf;
int sep_id, is_elf, i;
vir_bytes text_base, data_base;
assert(execi != NULL);
assert(execi->hdr != NULL);
@ -327,20 +485,39 @@ static int load_elf(struct exec_info *execi)
proc_e = execi->proc_e;
vp = execi->vp;
/* this function can load the dynamic linker, but that
* shouldn't require an interpreter itself.
*/
i = elf_has_interpreter(execi->hdr, execi->hdr_len, NULL, 0);
if(i > 0) {
printf("VFS: cannot load dynamically linked executable\n");
return ENOEXEC;
}
/* Read the file header and extract the segment sizes. */
r = read_header_elf(execi->hdr, &text_vaddr, &text_paddr,
r = read_header_elf(execi->hdr, execi->hdr_len, &text_vaddr, &text_paddr,
&text_filebytes, &text_membytes,
&data_vaddr, &data_paddr,
&data_filebytes, &data_membytes,
&execi->pc, &text_offset, &data_offset);
if (r != OK) return(r);
if (r != OK) {
return(r);
}
if(elf_phdr(execi->hdr, execi->hdr_len, &execi->elf_phdr) == OK)
if(execi->elf_phdr == 0) /* 0 should indicate: not known */
printf("VFS: warning: unexpected zero elf_phdr\n");
sep_id = 0;
is_elf = 1;
tot_bytes = 0; /* Use default stack size */
text_base = trunc_page(text_vaddr);
data_base = trunc_page(data_vaddr);
execi->elf_base = MIN(text_base, data_base);
r = exec_newmem(proc_e,
trunc_page(text_vaddr), text_membytes,
trunc_page(data_vaddr), data_membytes,
text_base, text_membytes,
data_base, data_membytes,
tot_bytes, execi->frame_len, sep_id, is_elf,
vp->v_dev, vp->v_inode_nr, execi->sb.st_ctime,
execi->progname, execi->new_uid, execi->new_gid,
@ -424,12 +601,12 @@ static int exec_newmem(
/*===========================================================================*
* is_script *
*===========================================================================*/
static int is_script(const char *exec_hdr, size_t exec_len)
static int is_script(struct exec_info *execi)
{
/* Is Interpreted script? */
assert(exec_hdr != NULL);
assert(execi->hdr != NULL);
return(exec_hdr[0] == '#' && exec_hdr[1] == '!' && exec_len >= 2);
return(execi->hdr[0] == '#' && execi->hdr[1] == '!' && execi->hdr_len >= 2);
}
/*===========================================================================*
@ -695,23 +872,27 @@ static void clo_exec(struct fproc *rfp)
/*===========================================================================*
* map_header *
*===========================================================================*/
static int map_header(char **exec_hdr, const struct vnode *vp)
static int map_header(struct exec_info *execi)
{
int r;
u64_t new_pos;
unsigned int cum_io;
off_t pos;
static char hdr[PAGE_SIZE]; /* Assume that header is not larger than a page */
pos = 0; /* Read from the start of the file */
r = req_readwrite(vp->v_fs_e, vp->v_inode_nr, cvul64(pos), READING,
VFS_PROC_NR, hdr, MIN(vp->v_size, PAGE_SIZE),
&new_pos, &cum_io);
/* How much is sensible to read */
execi->hdr_len = MIN(execi->vp->v_size, sizeof(hdr));
execi->hdr = hdr;
r = req_readwrite(execi->vp->v_fs_e, execi->vp->v_inode_nr,
cvul64(pos), READING, VFS_PROC_NR, hdr,
execi->hdr_len, &new_pos, &cum_io);
if (r != OK) {
printf("VFS: exec: map_header: req_readwrite failed\n");
return(r);
}
*exec_hdr = hdr;
return(OK);
}

9
servers/vfs/exec.h
View file

@ -4,6 +4,7 @@
struct exec_info {
int proc_e; /* Process endpoint */
char *hdr; /* Exec file's header */
int hdr_len; /* How many bytes are in hdr */
vir_bytes pc; /* Entry point of exec file */
vir_bytes stack_top; /* Top of the stack */
vir_bytes frame_len; /* Stack size */
@ -12,8 +13,16 @@ struct exec_info {
int load_text; /* Load text section? */
int setugid; /* Allow set{u,g}id execution? */
struct vnode *vp; /* Exec file's vnode */
struct vmnt *vmp; /* Exec file's vmnt */
struct stat sb; /* Exec file's stat structure */
char progname[PROC_NAME_LEN]; /* Program name */
int userflags; /* exec() flags from userland */
/* fields only used by elf and in VFS */
int is_dyn; /* Dynamically linked executable */
vir_bytes elf_phdr; /* Program header location */
vir_bytes elf_base; /* Userland addr load address */
int elf_main_fd; /* Dyn: FD of main program execuatble */
};
#endif /* !_VFS_EXEC_H_ */

1
servers/vfs/fproc.h
View file

@ -46,6 +46,7 @@ EXTERN struct fproc {
mutex_t fp_lock; /* mutex to lock fproc object */
struct job fp_job; /* pending job */
thread_t fp_wtid; /* Thread ID of worker */
char fp_name[PROC_NAME_LEN]; /* Last exec() */
#if LOCK_DEBUG
int fp_vp_rdlocks; /* number of read-only locks on vnodes */
int fp_vmnt_rdlocks; /* number of read-only locks on vmnts */

5
servers/vfs/main.c
View file

@ -791,7 +791,7 @@ void reply(endpoint_t whom, int result)
static void service_pm_postponed(void)
{
int r;
vir_bytes pc;
vir_bytes pc, newsp;
switch(job_call_nr) {
case PM_EXEC:
@ -807,13 +807,14 @@ static void service_pm_postponed(void)
stack_frame_len = (size_t) job_m_in.PM_FRAME_LEN;
r = pm_exec(proc_e, exec_path, exec_path_len, stack_frame,
stack_frame_len, &pc);
stack_frame_len, &pc, &newsp, m_in.PM_EXECFLAGS);
/* Reply status to PM */
m_out.m_type = PM_EXEC_REPLY;
m_out.PM_PROC = proc_e;
m_out.PM_PC = (void*) pc;
m_out.PM_STATUS = r;
m_out.PM_NEWSP = (void *) newsp;
}
break;

4
servers/vfs/proto.h
View file

@ -70,8 +70,8 @@ int map_service(struct rprocpub *rpub);
void write_elf_core_file(struct filp *f, int csig, char *exe_name);
/* exec.c */
int pm_exec(int proc_e, vir_bytes path, size_t path_len, vir_bytes frame,
size_t frame_len, vir_bytes *pc);
int pm_exec(endpoint_t proc_e, vir_bytes path, size_t path_len, vir_bytes frame,
size_t frame_len, vir_bytes *pc, vir_bytes *newsp, int flags);
#define check_bsf_lock() do { \
assert(mutex_trylock(&bsf_lock) == 0); \
unlock_bsf(); \