34a8901eb8
. if not, NULL *interp is dereferenced
722 lines
21 KiB
C
722 lines
21 KiB
C
/* This file handles the EXEC system call. It performs the work as follows:
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* - see if the permissions allow the file to be executed
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* - read the header and extract the sizes
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* - fetch the initial args and environment from the user space
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* - allocate the memory for the new process
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* - copy the initial stack from PM to the process
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* - read in the text and data segments and copy to the process
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* - take care of setuid and setgid bits
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* - fix up 'mproc' table
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* - tell kernel about EXEC
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* - save offset to initial argc (for ps)
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*
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* The entry points into this file are:
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* pm_exec: perform the EXEC system call
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*/
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#include "fs.h"
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#include <sys/stat.h>
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#include <minix/callnr.h>
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#include <minix/endpoint.h>
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#include <minix/com.h>
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#include <minix/u64.h>
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#include <a.out.h>
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#include <signal.h>
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#include <stdlib.h>
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#include <string.h>
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#include <dirent.h>
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#include <sys/param.h>
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#include "fproc.h"
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#include "path.h"
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#include "param.h"
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#include "vnode.h"
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#include <minix/vfsif.h>
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#include <assert.h>
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#include <libexec.h>
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#include "exec.h"
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FORWARD _PROTOTYPE( void lock_exec, (void) );
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FORWARD _PROTOTYPE( void unlock_exec, (void) );
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FORWARD _PROTOTYPE( int exec_newmem, (int proc_e, vir_bytes text_addr, vir_bytes text_bytes,
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vir_bytes data_addr, vir_bytes data_bytes,
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vir_bytes tot_bytes, vir_bytes frame_len, int sep_id,
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int is_elf, dev_t st_dev, ino_t st_ino, time_t ctime,
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char *progname, int new_uid, int new_gid,
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vir_bytes *stack_topp, int *load_textp,
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int *setugidp) );
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FORWARD _PROTOTYPE( int is_script, (const char *exec_hdr, size_t exec_len));
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FORWARD _PROTOTYPE( int patch_stack, (struct vnode *vp, char stack[ARG_MAX],
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vir_bytes *stk_bytes, char path[PATH_MAX]) );
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FORWARD _PROTOTYPE( int insert_arg, (char stack[ARG_MAX], vir_bytes *stk_bytes,
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char *arg, int replace) );
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FORWARD _PROTOTYPE( void patch_ptr, (char stack[ARG_MAX], vir_bytes base));
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FORWARD _PROTOTYPE( void clo_exec, (struct fproc *rfp) );
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FORWARD _PROTOTYPE( int read_seg, (struct vnode *vp, off_t off, int proc_e,
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int seg, vir_bytes seg_addr,
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phys_bytes seg_bytes) );
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FORWARD _PROTOTYPE( int load_aout, (struct exec_info *execi) );
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FORWARD _PROTOTYPE( int load_elf, (struct exec_info *execi) );
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FORWARD _PROTOTYPE( int map_header, (char **exec_hdr,
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const struct vnode *vp) );
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#define PTRSIZE sizeof(char *) /* Size of pointers in argv[] and envp[]. */
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/* Array of loaders for different object file formats */
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struct exec_loaders {
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int (*load_object)(struct exec_info *);
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};
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PRIVATE const struct exec_loaders exec_loaders[] = {
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{ load_aout },
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{ load_elf },
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{ NULL }
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};
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PRIVATE char hdr[PAGE_SIZE]; /* Assume that header is not larger than a page */
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/*===========================================================================*
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* lock_exec *
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*===========================================================================*/
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PRIVATE void lock_exec(void)
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{
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message org_m_in;
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struct fproc *org_fp;
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struct worker_thread *org_self;
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/* First try to get it right off the bat */
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if (mutex_trylock(&exec_lock) == 0)
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return;
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org_m_in = m_in;
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org_fp = fp;
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org_self = self;
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if (mutex_lock(&exec_lock) != 0)
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panic("Could not obtain lock on exec");
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m_in = org_m_in;
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fp = org_fp;
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self = org_self;
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}
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/*===========================================================================*
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* unlock_exec *
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*===========================================================================*/
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PRIVATE void unlock_exec(void)
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{
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if (mutex_unlock(&exec_lock) != 0)
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panic("Could not release lock on exec");
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}
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/*===========================================================================*
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* pm_exec *
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*===========================================================================*/
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PUBLIC int pm_exec(int proc_e, char *path, vir_bytes path_len, char *frame,
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vir_bytes frame_len, vir_bytes *pc)
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{
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/* Perform the execve(name, argv, envp) call. The user library builds a
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* complete stack image, including pointers, args, environ, etc. The stack
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* is copied to a buffer inside VFS, and then to the new core image.
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*/
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int r, r1, round, slot;
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vir_bytes vsp;
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struct fproc *rfp;
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struct vnode *vp;
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struct vmnt *vmp;
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char *cp;
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static char mbuf[ARG_MAX]; /* buffer for stack and zeroes */
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struct exec_info execi;
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int i;
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char fullpath[PATH_MAX];
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struct lookup resolve;
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lock_exec();
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okendpt(proc_e, &slot);
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rfp = fp = &fproc[slot];
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vp = NULL;
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lookup_init(&resolve, fullpath, PATH_NOFLAGS, &vmp, &vp);
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resolve.l_vmnt_lock = VMNT_READ;
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resolve.l_vnode_lock = VNODE_READ;
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/* Get the exec file name. */
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if ((r = fetch_name(path, path_len, 0, fullpath)) != OK)
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goto pm_execfinal;
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/* Fetch the stack from the user before destroying the old core image. */
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if (frame_len > ARG_MAX) {
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printf("VFS: pm_exec: stack too big\n");
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r = ENOMEM; /* stack too big */
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goto pm_execfinal;
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}
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r = sys_datacopy(proc_e, (vir_bytes) frame, SELF, (vir_bytes) mbuf,
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(phys_bytes) frame_len);
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if (r != OK) { /* can't fetch stack (e.g. bad virtual addr) */
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printf("VFS: pm_exec: sys_datacopy failed\n");
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goto pm_execfinal;
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}
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/* The default is to keep the original user and group IDs */
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execi.new_uid = rfp->fp_effuid;
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execi.new_gid = rfp->fp_effgid;
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for (round = 0; round < 2; round++) {
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/* round = 0 (first attempt), or 1 (interpreted script) */
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/* Save the name of the program */
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(cp = strrchr(fullpath, '/')) ? cp++ : (cp = fullpath);
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strncpy(execi.progname, cp, PROC_NAME_LEN-1);
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execi.progname[PROC_NAME_LEN-1] = '\0';
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execi.setugid = 0;
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/* Open executable */
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if ((vp = eat_path(&resolve, fp)) == NULL) {
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r = err_code;
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goto pm_execfinal;
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}
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execi.vp = vp;
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unlock_vmnt(vmp);
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if ((vp->v_mode & I_TYPE) != I_REGULAR)
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r = ENOEXEC;
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else if ((r1 = forbidden(vp, X_BIT)) != OK)
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r = r1;
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else
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r = req_stat(vp->v_fs_e, vp->v_inode_nr, VFS_PROC_NR,
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(char *) &(execi.sb), 0, 0);
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if (r != OK) goto pm_execfinal;
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if (round == 0) {
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/* Deal with setuid/setgid executables */
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if (vp->v_mode & I_SET_UID_BIT) {
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execi.new_uid = vp->v_uid;
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execi.setugid = 1;
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}
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if (vp->v_mode & I_SET_GID_BIT) {
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execi.new_gid = vp->v_gid;
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execi.setugid = 1;
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}
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}
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r = map_header(&execi.hdr, execi.vp);
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if (r != OK) goto pm_execfinal;
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if (!is_script(execi.hdr, execi.vp->v_size) || round != 0)
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break;
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/* Get fresh copy of the file name. */
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if ((r = fetch_name(path, path_len, 0, fullpath)) != OK)
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printf("VFS pm_exec: 2nd fetch_name failed\n");
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else if ((r = patch_stack(vp, mbuf, &frame_len, fullpath)) != OK)
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printf("VFS pm_exec: patch_stack failed\n");
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unlock_vnode(vp);
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put_vnode(vp);
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vp = NULL;
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if (r != OK) goto pm_execfinal;
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}
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execi.proc_e = proc_e;
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execi.frame_len = frame_len;
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for (i = 0; exec_loaders[i].load_object != NULL; i++) {
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r = (*exec_loaders[i].load_object)(&execi);
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/* Loaded successfully, so no need to try other loaders */
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if (r == OK) break;
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}
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if (r != OK) { /* No exec loader could load the object */
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r = ENOEXEC;
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goto pm_execfinal;
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}
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/* Save off PC */
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*pc = execi.pc;
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/* Patch up stack and copy it from VFS to new core image. */
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vsp = execi.stack_top;
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vsp -= frame_len;
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patch_ptr(mbuf, vsp);
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if ((r = sys_datacopy(SELF, (vir_bytes) mbuf, proc_e, (vir_bytes) vsp,
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(phys_bytes)frame_len)) != OK) {
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printf("VFS: datacopy failed (%d) trying to copy to %lu\n", r, vsp);
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goto pm_execfinal;
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}
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if (r != OK) goto pm_execfinal;
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clo_exec(rfp);
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if (execi.setugid) {
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/* If after loading the image we're still allowed to run with
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* setuid or setgid, change credentials now */
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rfp->fp_effuid = execi.new_uid;
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rfp->fp_effgid = execi.new_gid;
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}
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pm_execfinal:
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if (vp != NULL) {
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unlock_vnode(vp);
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put_vnode(vp);
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}
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unlock_exec();
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return(r);
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}
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/*===========================================================================*
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* load_aout *
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*===========================================================================*/
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PRIVATE int load_aout(struct exec_info *execi)
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{
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int r;
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struct vnode *vp;
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int proc_e;
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off_t off;
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int hdrlen;
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int sep_id;
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vir_bytes text_bytes, data_bytes, bss_bytes;
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phys_bytes tot_bytes; /* total space for program, including gap */
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assert(execi != NULL);
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assert(execi->hdr != NULL);
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assert(execi->vp != NULL);
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proc_e = execi->proc_e;
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vp = execi->vp;
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/* Read the file header and extract the segment sizes. */
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r = read_header_aout(execi->hdr, execi->vp->v_size, &sep_id,
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&text_bytes, &data_bytes, &bss_bytes,
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&tot_bytes, &execi->pc, &hdrlen);
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if (r != OK) return(r);
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r = exec_newmem(proc_e, 0 /* text_addr */, text_bytes,
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0 /* data_addr */, data_bytes + bss_bytes, tot_bytes,
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execi->frame_len, sep_id, 0 /* is_elf */, vp->v_dev, vp->v_inode_nr,
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execi->sb.st_ctime,
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execi->progname, execi->new_uid, execi->new_gid,
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&execi->stack_top, &execi->load_text, &execi->setugid);
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if (r != OK) {
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printf("VFS: load_aout: exec_newmem failed: %d\n", r);
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return(r);
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}
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off = hdrlen;
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/* Read in text and data segments. */
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if (execi->load_text)
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r = read_seg(vp, off, proc_e, T, 0, text_bytes);
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off += text_bytes;
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if (r == OK)
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r = read_seg(vp, off, proc_e, D, 0, data_bytes);
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return(r);
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}
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/*===========================================================================*
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* load_elf *
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*===========================================================================*/
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PRIVATE int load_elf(struct exec_info *execi)
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{
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int r;
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struct vnode *vp;
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int proc_e;
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phys_bytes tot_bytes; /* total space for program, including gap */
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vir_bytes text_vaddr, text_paddr, text_filebytes, text_membytes;
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vir_bytes data_vaddr, data_paddr, data_filebytes, data_membytes;
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off_t text_offset, data_offset;
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int sep_id, is_elf;
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assert(execi != NULL);
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assert(execi->hdr != NULL);
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assert(execi->vp != NULL);
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proc_e = execi->proc_e;
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vp = execi->vp;
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/* Read the file header and extract the segment sizes. */
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r = read_header_elf(execi->hdr, &text_vaddr, &text_paddr,
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&text_filebytes, &text_membytes,
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&data_vaddr, &data_paddr,
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&data_filebytes, &data_membytes,
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&execi->pc, &text_offset, &data_offset);
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if (r != OK) return(r);
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sep_id = 0;
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is_elf = 1;
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tot_bytes = 0; /* Use default stack size */
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r = exec_newmem(proc_e,
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trunc_page(text_vaddr), text_membytes,
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trunc_page(data_vaddr), data_membytes,
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tot_bytes, execi->frame_len, sep_id, is_elf,
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vp->v_dev, vp->v_inode_nr, execi->sb.st_ctime,
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execi->progname, execi->new_uid, execi->new_gid,
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&execi->stack_top, &execi->load_text, &execi->setugid);
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if (r != OK) {
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printf("VFS: load_elf: exec_newmem failed: %d\n", r);
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return(r);
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}
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/* Read in text and data segments. */
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if (execi->load_text)
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r = read_seg(vp, text_offset, proc_e, T, text_vaddr, text_filebytes);
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if (r == OK)
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r = read_seg(vp, data_offset, proc_e, D, data_vaddr, data_filebytes);
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return(r);
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}
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/*===========================================================================*
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* exec_newmem *
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*===========================================================================*/
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PRIVATE int exec_newmem(
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int proc_e,
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vir_bytes text_addr,
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vir_bytes text_bytes,
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vir_bytes data_addr,
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vir_bytes data_bytes,
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vir_bytes tot_bytes,
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vir_bytes frame_len,
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int sep_id,
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int is_elf,
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dev_t st_dev,
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ino_t st_ino,
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time_t ctime,
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char *progname,
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int new_uid,
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int new_gid,
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vir_bytes *stack_topp,
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int *load_textp,
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int *setugidp
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)
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{
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/* Allocate a new memory map for a process that tries to exec */
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int r;
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struct exec_newmem e;
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message m;
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assert(setugidp != NULL);
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e.text_addr = text_addr;
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e.text_bytes = text_bytes;
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e.data_addr = data_addr;
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e.data_bytes = data_bytes;
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e.tot_bytes = tot_bytes;
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e.args_bytes = frame_len;
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e.sep_id = sep_id;
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e.is_elf = is_elf;
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e.st_dev = st_dev;
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e.st_ino = st_ino;
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e.enst_ctime = ctime;
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e.new_uid = new_uid;
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e.new_gid = new_gid;
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e.setugid = *setugidp;
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strncpy(e.progname, progname, sizeof(e.progname)-1);
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e.progname[sizeof(e.progname)-1] = '\0';
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m.m_type = EXEC_NEWMEM;
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m.EXC_NM_PROC = proc_e;
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m.EXC_NM_PTR = (char *)&e;
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if ((r = sendrec(PM_PROC_NR, &m)) != OK) return(r);
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*stack_topp = m.m1_i1;
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*load_textp = !!(m.m1_i2 & EXC_NM_RF_LOAD_TEXT);
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*setugidp = !!(m.m1_i2 & EXC_NM_RF_ALLOW_SETUID);
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return(m.m_type);
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}
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/*===========================================================================*
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* is_script *
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*===========================================================================*/
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PRIVATE int is_script(const char *exec_hdr, size_t exec_len)
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{
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/* Is Interpreted script? */
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assert(exec_hdr != NULL);
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return(exec_hdr[0] == '#' && exec_hdr[1] == '!' && exec_len >= 2);
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}
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/*===========================================================================*
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* patch_stack *
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*===========================================================================*/
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PRIVATE int patch_stack(vp, stack, stk_bytes, path)
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struct vnode *vp; /* pointer for open script file */
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char stack[ARG_MAX]; /* pointer to stack image within VFS */
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vir_bytes *stk_bytes; /* size of initial stack */
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char path[PATH_MAX]; /* path to script file */
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{
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/* Patch the argument vector to include the path name of the script to be
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* interpreted, and all strings on the #! line. Returns the path name of
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* the interpreter.
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*/
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enum { INSERT=FALSE, REPLACE=TRUE };
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int n, r;
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off_t pos;
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char *sp, *interp = NULL;
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u64_t new_pos;
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unsigned int cum_io;
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char buf[_MAX_BLOCK_SIZE];
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/* Make 'path' the new argv[0]. */
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if (!insert_arg(stack, stk_bytes, path, REPLACE)) return(ENOMEM);
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pos = 0; /* Read from the start of the file */
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/* Issue request */
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r = req_readwrite(vp->v_fs_e, vp->v_inode_nr, cvul64(pos), READING,
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VFS_PROC_NR, buf, _MAX_BLOCK_SIZE, &new_pos, &cum_io);
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if (r != OK) return(r);
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n = vp->v_size;
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if (n > _MAX_BLOCK_SIZE)
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n = _MAX_BLOCK_SIZE;
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if (n < 2) return ENOEXEC;
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sp = &(buf[2]); /* just behind the #! */
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n -= 2;
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if (n > PATH_MAX) n = PATH_MAX;
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/* Use the 'path' variable for temporary storage */
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memcpy(path, sp, n);
|
|
|
|
if ((sp = memchr(path, '\n', n)) == NULL) /* must be a proper line */
|
|
return(ENOEXEC);
|
|
|
|
/* Move sp backwards through script[], prepending each string to stack. */
|
|
for (;;) {
|
|
/* skip spaces behind argument. */
|
|
while (sp > path && (*--sp == ' ' || *sp == '\t')) {}
|
|
if (sp == path) break;
|
|
|
|
sp[1] = 0;
|
|
/* Move to the start of the argument. */
|
|
while (sp > path && sp[-1] != ' ' && sp[-1] != '\t') --sp;
|
|
|
|
interp = sp;
|
|
if (!insert_arg(stack, stk_bytes, sp, INSERT)) {
|
|
printf("VFS: patch_stack: insert_arg failed\n");
|
|
return(ENOMEM);
|
|
}
|
|
}
|
|
|
|
if(!interp)
|
|
return ENOEXEC;
|
|
|
|
/* Round *stk_bytes up to the size of a pointer for alignment contraints. */
|
|
*stk_bytes= ((*stk_bytes + PTRSIZE - 1) / PTRSIZE) * PTRSIZE;
|
|
|
|
if (interp != path)
|
|
memmove(path, interp, strlen(interp)+1);
|
|
return(OK);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* insert_arg *
|
|
*===========================================================================*/
|
|
PRIVATE int insert_arg(
|
|
char stack[ARG_MAX], /* pointer to stack image within PM */
|
|
vir_bytes *stk_bytes, /* size of initial stack */
|
|
char *arg, /* argument to prepend/replace as new argv[0] */
|
|
int replace
|
|
)
|
|
{
|
|
/* Patch the stack so that arg will become argv[0]. Be careful, the stack may
|
|
* be filled with garbage, although it normally looks like this:
|
|
* nargs argv[0] ... argv[nargs-1] NULL envp[0] ... NULL
|
|
* followed by the strings "pointed" to by the argv[i] and the envp[i]. The
|
|
* pointers are really offsets from the start of stack.
|
|
* Return true iff the operation succeeded.
|
|
*/
|
|
int offset, a0, a1, old_bytes = *stk_bytes;
|
|
|
|
/* Prepending arg adds at least one string and a zero byte. */
|
|
offset = strlen(arg) + 1;
|
|
|
|
a0 = (int) ((char **) stack)[1]; /* argv[0] */
|
|
if (a0 < 4 * PTRSIZE || a0 >= old_bytes) return(FALSE);
|
|
|
|
a1 = a0; /* a1 will point to the strings to be moved */
|
|
if (replace) {
|
|
/* Move a1 to the end of argv[0][] (argv[1] if nargs > 1). */
|
|
do {
|
|
if (a1 == old_bytes) return(FALSE);
|
|
--offset;
|
|
} while (stack[a1++] != 0);
|
|
} else {
|
|
offset += PTRSIZE; /* new argv[0] needs new pointer in argv[] */
|
|
a0 += PTRSIZE; /* location of new argv[0][]. */
|
|
}
|
|
|
|
/* stack will grow by offset bytes (or shrink by -offset bytes) */
|
|
if ((*stk_bytes += offset) > ARG_MAX) return(FALSE);
|
|
|
|
/* Reposition the strings by offset bytes */
|
|
memmove(stack + a1 + offset, stack + a1, old_bytes - a1);
|
|
|
|
strcpy(stack + a0, arg); /* Put arg in the new space. */
|
|
|
|
if (!replace) {
|
|
/* Make space for a new argv[0]. */
|
|
memmove(stack + 2 * PTRSIZE, stack + 1 * PTRSIZE, a0 - 2 * PTRSIZE);
|
|
|
|
((char **) stack)[0]++; /* nargs++; */
|
|
}
|
|
/* Now patch up argv[] and envp[] by offset. */
|
|
patch_ptr(stack, (vir_bytes) offset);
|
|
((char **) stack)[1] = (char *) a0; /* set argv[0] correctly */
|
|
return(TRUE);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* patch_ptr *
|
|
*===========================================================================*/
|
|
PRIVATE void patch_ptr(
|
|
char stack[ARG_MAX], /* pointer to stack image within PM */
|
|
vir_bytes base /* virtual address of stack base inside user */
|
|
)
|
|
{
|
|
/* When doing an exec(name, argv, envp) call, the user builds up a stack
|
|
* image with arg and env pointers relative to the start of the stack. Now
|
|
* these pointers must be relocated, since the stack is not positioned at
|
|
* address 0 in the user's address space.
|
|
*/
|
|
|
|
char **ap, flag;
|
|
vir_bytes v;
|
|
|
|
flag = 0; /* counts number of 0-pointers seen */
|
|
ap = (char **) stack; /* points initially to 'nargs' */
|
|
ap++; /* now points to argv[0] */
|
|
while (flag < 2) {
|
|
if (ap >= (char **) &stack[ARG_MAX]) return; /* too bad */
|
|
if (*ap != NULL) {
|
|
v = (vir_bytes) *ap; /* v is relative pointer */
|
|
v += base; /* relocate it */
|
|
*ap = (char *) v; /* put it back */
|
|
} else {
|
|
flag++;
|
|
}
|
|
ap++;
|
|
}
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* read_seg *
|
|
*===========================================================================*/
|
|
PRIVATE int read_seg(
|
|
struct vnode *vp, /* inode descriptor to read from */
|
|
off_t off, /* offset in file */
|
|
int proc_e, /* process number (endpoint) */
|
|
int seg, /* T, D, or S */
|
|
vir_bytes seg_addr, /* address to load segment */
|
|
phys_bytes seg_bytes /* how much is to be transferred? */
|
|
)
|
|
{
|
|
/*
|
|
* The byte count on read is usually smaller than the segment count, because
|
|
* a segment is padded out to a click multiple, and the data segment is only
|
|
* partially initialized.
|
|
*/
|
|
int r;
|
|
unsigned n, o;
|
|
u64_t new_pos;
|
|
unsigned int cum_io;
|
|
static char buf[128 * 1024];
|
|
|
|
assert((seg == T)||(seg == D));
|
|
|
|
/* Make sure that the file is big enough */
|
|
if (vp->v_size < off+seg_bytes) return(EIO);
|
|
|
|
if (seg == T) {
|
|
/* We have to use a copy loop until safecopies support segments */
|
|
o = 0;
|
|
while (o < seg_bytes) {
|
|
n = seg_bytes - o;
|
|
if (n > sizeof(buf))
|
|
n = sizeof(buf);
|
|
|
|
if ((r = req_readwrite(vp->v_fs_e,vp->v_inode_nr,cvul64(off+o),
|
|
READING, VFS_PROC_NR, buf,
|
|
n, &new_pos, &cum_io)) != OK) {
|
|
printf("VFS: read_seg: req_readwrite failed (text)\n");
|
|
return(r);
|
|
}
|
|
|
|
if (cum_io != n) {
|
|
printf(
|
|
"VFSread_seg segment has not been read properly by exec() \n");
|
|
return(EIO);
|
|
}
|
|
|
|
if ((r = sys_vircopy(VFS_PROC_NR, D, (vir_bytes)buf, proc_e,
|
|
seg, seg_addr + o, n)) != OK) {
|
|
printf("VFS: read_seg: copy failed (text)\n");
|
|
return(r);
|
|
}
|
|
|
|
o += n;
|
|
}
|
|
return(OK);
|
|
} else if (seg == D) {
|
|
|
|
if ((r = req_readwrite(vp->v_fs_e, vp->v_inode_nr, cvul64(off), READING,
|
|
proc_e, (char*)seg_addr, seg_bytes,
|
|
&new_pos, &cum_io)) != OK) {
|
|
printf("VFS: read_seg: req_readwrite failed (data)\n");
|
|
return(r);
|
|
}
|
|
|
|
if (r == OK && cum_io != seg_bytes)
|
|
printf("VFS: read_seg segment has not been read properly by exec()\n");
|
|
|
|
return(r);
|
|
}
|
|
|
|
return(OK);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* clo_exec *
|
|
*===========================================================================*/
|
|
PRIVATE void clo_exec(struct fproc *rfp)
|
|
{
|
|
/* Files can be marked with the FD_CLOEXEC bit (in fp->fp_cloexec).
|
|
*/
|
|
int i;
|
|
|
|
/* Check the file desriptors one by one for presence of FD_CLOEXEC. */
|
|
for (i = 0; i < OPEN_MAX; i++)
|
|
if ( FD_ISSET(i, &rfp->fp_cloexec_set))
|
|
(void) close_fd(rfp, i);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* map_header *
|
|
*===========================================================================*/
|
|
PRIVATE int map_header(char **exec_hdr, const struct vnode *vp)
|
|
{
|
|
int r;
|
|
u64_t new_pos;
|
|
unsigned int cum_io;
|
|
off_t pos;
|
|
|
|
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);
|
|
if (r != OK) {
|
|
printf("VFS: exec: map_header: req_readwrite failed\n");
|
|
return(r);
|
|
}
|
|
|
|
*exec_hdr = hdr;
|
|
return(OK);
|
|
}
|