. ld.so is linked at 0 but it can relocate itself; we wish to load ld.so higher though to trap NULL dereferences. if we know we have to execute ld.so, vfs tells libexec to put it higher.
681 lines
21 KiB
C
681 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 <machine/vmparam.h>
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#include <assert.h>
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#include <fcntl.h>
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#define _KERNEL /* for ELF_AUX_ENTRIES */
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#include <libexec.h>
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/* fields only used by elf and in VFS */
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struct vfs_exec_info {
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struct exec_info args; /* libexec exec args */
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struct vnode *vp; /* Exec file's vnode */
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struct vmnt *vmp; /* Exec file's vmnt */
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struct stat sb; /* Exec file's stat structure */
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int userflags; /* exec() flags from userland */
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int is_dyn; /* Dynamically linked executable */
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int elf_main_fd; /* Dyn: FD of main program execuatble */
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char execname[PATH_MAX]; /* Full executable invocation */
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};
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static void lock_exec(void);
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static void unlock_exec(void);
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static int patch_stack(struct vnode *vp, char stack[ARG_MAX],
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size_t *stk_bytes, char path[PATH_MAX]);
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static int is_script(struct vfs_exec_info *execi);
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static int insert_arg(char stack[ARG_MAX], size_t *stk_bytes, char *arg,
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int replace);
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static void clo_exec(struct fproc *rfp);
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static int stack_prepare_elf(struct vfs_exec_info *execi,
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char *curstack, size_t *frame_len, vir_bytes *vsp, int *extrabase);
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static int map_header(struct vfs_exec_info *execi);
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static int read_seg(struct exec_info *execi, off_t off, off_t seg_addr, size_t seg_bytes);
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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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typedef int (*exechook_t)(struct vfs_exec_info *execpackage);
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typedef int (*stackhook_t)(struct vfs_exec_info *execi, char *curstack,
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size_t *frame_len, vir_bytes *, int *extrabase);
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struct exec_loaders {
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libexec_exec_loadfunc_t load_object; /* load executable into memory */
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stackhook_t setup_stack; /* prepare stack before argc and argv push */
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};
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static const struct exec_loaders exec_loaders[] = {
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{ libexec_load_elf, stack_prepare_elf },
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{ NULL, NULL }
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};
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/*===========================================================================*
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* lock_exec *
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*===========================================================================*/
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static void lock_exec(void)
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{
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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_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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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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static 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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* get_read_vp *
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*===========================================================================*/
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static int get_read_vp(struct vfs_exec_info *execi,
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char *fullpath, int copyprogname, int sugid, struct lookup *resolve, struct fproc *fp)
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{
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/* Make the executable that we want to exec() into the binary pointed
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* to by 'fullpath.' This function fills in necessary details in the execi
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* structure, such as opened vnode. It unlocks and releases the vnode if
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* it was already there. This makes it easy to change the executable
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* during the exec(), which is often necessary, by calling this function
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* more than once. This is specifically necessary when we discover the
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* executable is actually a script or a dynamically linked executable.
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*/
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int r;
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/* Caller wants to switch vp to the file in 'fullpath.'
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* unlock and put it first if there is any there.
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*/
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if(execi->vp) {
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unlock_vnode(execi->vp);
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put_vnode(execi->vp);
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execi->vp = NULL;
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}
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/* Remember/overwrite the executable name if requested. */
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if(copyprogname) {
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char *cp = strrchr(fullpath, '/');
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if(cp) cp++;
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else cp = fullpath;
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strlcpy(execi->args.progname, cp, sizeof(execi->args.progname));
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execi->args.progname[sizeof(execi->args.progname)-1] = '\0';
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}
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/* Open executable */
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if ((execi->vp = eat_path(resolve, fp)) == NULL)
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return err_code;
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unlock_vmnt(execi->vmp);
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if (!S_ISREG(execi->vp->v_mode))
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return ENOEXEC;
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else if ((r = forbidden(fp, execi->vp, X_BIT)) != OK)
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return r;
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else
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r = req_stat(execi->vp->v_fs_e, execi->vp->v_inode_nr,
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VFS_PROC_NR, (vir_bytes) &(execi->sb), 0);
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if (r != OK) return r;
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/* If caller wants us to, honour suid/guid mode bits. */
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if (sugid) {
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/* Deal with setuid/setgid executables */
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if (execi->vp->v_mode & I_SET_UID_BIT) {
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execi->args.new_uid = execi->vp->v_uid;
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execi->args.allow_setuid = 1;
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}
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if (execi->vp->v_mode & I_SET_GID_BIT) {
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execi->args.new_gid = execi->vp->v_gid;
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execi->args.allow_setuid = 1;
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}
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}
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/* Read in first chunk of file. */
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if((r=map_header(execi)) != OK)
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return r;
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return OK;
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}
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#define FAILCHECK(expr) if((r=(expr)) != OK) { goto pm_execfinal; } while(0)
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#define Get_read_vp(e,f,p,s,rs,fp) do { \
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r=get_read_vp(&e,f,p,s,rs,fp); if(r != OK) { FAILCHECK(r); } \
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} while(0)
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/*===========================================================================*
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* pm_exec *
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*===========================================================================*/
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int pm_exec(endpoint_t proc_e, vir_bytes path, size_t path_len,
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vir_bytes frame, size_t frame_len, vir_bytes *pc,
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vir_bytes *newsp, int user_exec_flags)
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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, slot;
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vir_bytes vsp;
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struct fproc *rfp;
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int extrabase = 0;
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static char mbuf[ARG_MAX]; /* buffer for stack and zeroes */
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struct vfs_exec_info execi;
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int i;
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static char fullpath[PATH_MAX],
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elf_interpreter[PATH_MAX],
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finalexec[PATH_MAX];
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struct lookup resolve;
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stackhook_t makestack = NULL;
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lock_exec();
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/* unset execi values are 0. */
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memset(&execi, 0, sizeof(execi));
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/* passed from exec() libc code */
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execi.userflags = user_exec_flags;
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execi.args.stack_high = kinfo.user_sp;
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execi.args.stack_size = DEFAULT_STACK_LIMIT;
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okendpt(proc_e, &slot);
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rfp = fp = &fproc[slot];
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lookup_init(&resolve, fullpath, PATH_NOFLAGS, &execi.vmp, &execi.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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/* 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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FAILCHECK(ENOMEM); /* stack too big */
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r = sys_datacopy(proc_e, (vir_bytes) frame, SELF, (vir_bytes) mbuf,
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(size_t) 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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FAILCHECK(r);
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}
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/* The default is to keep the original user and group IDs */
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execi.args.new_uid = rfp->fp_effuid;
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execi.args.new_gid = rfp->fp_effgid;
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/* Get the exec file name. */
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FAILCHECK(fetch_name(path, path_len, fullpath));
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strlcpy(finalexec, fullpath, PATH_MAX);
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/* Get_read_vp will return an opened vn in execi.
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* if necessary it releases the existing vp so we can
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* switch after we find out what's inside the file.
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* It reads the start of the file.
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*/
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Get_read_vp(execi, fullpath, 1, 1, &resolve, fp);
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/* If this is a script (i.e. has a #!/interpreter line),
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* retrieve the name of the interpreter and open that
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* executable instead.
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*/
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if(is_script(&execi)) {
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/* patch_stack will add interpreter name and
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* args to stack and retrieve the new binary
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* name into fullpath.
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*/
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FAILCHECK(fetch_name(path, path_len, fullpath));
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FAILCHECK(patch_stack(execi.vp, mbuf, &frame_len, fullpath));
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strlcpy(finalexec, fullpath, PATH_MAX);
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Get_read_vp(execi, fullpath, 1, 0, &resolve, fp);
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}
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/* If this is a dynamically linked executable, retrieve
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* the name of that interpreter in elf_interpreter and open that
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* executable instead. But open the current executable in an
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* fd for the current process.
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*/
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if(elf_has_interpreter(execi.args.hdr, execi.args.hdr_len,
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elf_interpreter, sizeof(elf_interpreter))) {
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/* Switch the executable vnode to the interpreter */
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execi.is_dyn = 1;
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/* The interpreter (loader) needs an fd to the main program,
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* which is currently in finalexec
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*/
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if((r = execi.elf_main_fd = common_open(finalexec, O_RDONLY, 0)) < 0) {
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printf("VFS: exec: dynamic: open main exec failed %s (%d)\n",
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fullpath, r);
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FAILCHECK(r);
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}
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/* ld.so is linked at 0, but it can relocate itself; we
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* want it higher to trap NULL pointer dereferences.
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*/
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execi.args.load_offset = 0x10000;
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/* Remember it */
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strlcpy(execi.execname, finalexec, PATH_MAX);
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/* The executable we need to execute first (loader)
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* is in elf_interpreter, and has to be in fullpath to
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* be looked up
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*/
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strlcpy(fullpath, elf_interpreter, PATH_MAX);
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Get_read_vp(execi, fullpath, 0, 0, &resolve, fp);
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}
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/* callback functions and data */
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execi.args.copymem = read_seg;
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execi.args.clearproc = libexec_clearproc_vm_procctl;
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execi.args.clearmem = libexec_clear_sys_memset;
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execi.args.allocmem_prealloc = libexec_alloc_mmap_prealloc;
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execi.args.allocmem_ondemand = libexec_alloc_mmap_ondemand;
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execi.args.opaque = &execi;
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execi.args.proc_e = proc_e;
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execi.args.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.args);
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/* Loaded successfully, so no need to try other loaders */
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if (r == OK) { makestack = exec_loaders[i].setup_stack; break; }
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}
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FAILCHECK(r);
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/* Inform PM */
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FAILCHECK(libexec_pm_newexec(proc_e, &execi.args));
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/* Save off PC */
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*pc = execi.args.pc;
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/* call a stack-setup function if this executable type wants it */
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vsp = execi.args.stack_high - frame_len;
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if(makestack) FAILCHECK(makestack(&execi, mbuf, &frame_len, &vsp, &extrabase));
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/* Patch up stack and copy it from VFS to new core image. */
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libexec_patch_ptr(mbuf, vsp + extrabase);
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FAILCHECK(sys_datacopy(SELF, (vir_bytes) mbuf, proc_e, (vir_bytes) vsp,
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(phys_bytes)frame_len));
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/* Return new stack pointer to caller */
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*newsp = vsp;
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clo_exec(rfp);
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if (execi.args.allow_setuid) {
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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.args.new_uid;
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rfp->fp_effgid = execi.args.new_gid;
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}
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/* Remember the new name of the process */
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strlcpy(rfp->fp_name, execi.args.progname, PROC_NAME_LEN);
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pm_execfinal:
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if (execi.vp != NULL) {
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unlock_vnode(execi.vp);
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put_vnode(execi.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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static int stack_prepare_elf(struct vfs_exec_info *execi, char *frame, size_t *framelen,
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vir_bytes *newsp, int *extrabase)
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{
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AuxInfo *a, *term;
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Elf_Ehdr *elf_header;
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int nulls;
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char **mysp = (char **) frame,
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**mysp_end = (char **) ((char *)frame + *framelen);
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if(!execi->is_dyn)
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return OK;
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assert(execi->args.hdr_len >= sizeof(*elf_header));
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elf_header = (Elf_Ehdr *) execi->args.hdr;
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/* exec() promises stack space. Now find it. */
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mysp++; /* skip argc */
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/* find a terminating NULL entry twice: one for argv[], one for envp[]. */
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for(nulls = 0; nulls < 2; nulls++) {
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assert(mysp < mysp_end);
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while(*mysp && mysp < mysp_end) mysp++; /* find terminating NULL */
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if(mysp >= mysp_end) {
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printf("VFS: malformed stack for exec()\n");
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return ENOEXEC;
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}
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assert(!*mysp);
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mysp++;
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}
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/* Userland provides a fully filled stack frame, with argc, argv, envp
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* and then all the argv and envp strings; consistent with ELF ABI, except
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* for a list of Aux vectors that should be between envp points and the
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* start of the strings.
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*
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* It would take some very unpleasant hackery to insert the aux vectors before
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* the strings, and correct all the pointers, so the exec code in libc makes
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* space for us first and indicates the fact it did this with this flag.
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*/
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if(!(execi->userflags & PMEF_AUXVECTORSPACE)) {
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char *f = (char *) mysp;
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int remain;
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vir_bytes extrabytes = sizeof(*a) * PMEF_AUXVECTORS;
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/* Create extrabytes more space */
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remain = *framelen - (int)(f - frame);
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if(*framelen + extrabytes >= ARG_MAX)
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return ENOMEM;
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*framelen += extrabytes;
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*newsp -= extrabytes;
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*extrabase += extrabytes;
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memmove(f+extrabytes, f, remain);
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memset(f, 0, extrabytes);
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}
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/* Ok, what mysp points to now we can use for the aux vectors. */
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a = (AuxInfo *) mysp;
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#define AUXINFO(type, value) \
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{ assert((char *) a < (char *) mysp_end); a->a_type = type; a->a_v = value; a++; }
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#if 0
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AUXINFO(AT_PHENT, elf_header->e_phentsize);
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AUXINFO(AT_PHNUM, elf_header->e_phnum);
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#endif
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AUXINFO(AT_BASE, execi->args.load_base);
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AUXINFO(AT_ENTRY, execi->args.pc);
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AUXINFO(AT_PAGESZ, PAGE_SIZE);
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AUXINFO(AT_EXECFD, execi->elf_main_fd);
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/* This is where we add the AT_NULL */
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term = a;
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/* Always terminate with AT_NULL */
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AUXINFO(AT_NULL, 0);
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/* Empty space starts here, if any. */
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if((execi->userflags & PMEF_EXECNAMESPACE1)
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&& strlen(execi->execname) < PMEF_EXECNAMELEN1) {
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char *spacestart;
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vir_bytes userp;
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/* Make space for the real closing AT_NULL entry. */
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AUXINFO(AT_NULL, 0);
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/* Empty space starts here; we can put the name here. */
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spacestart = (char *) a;
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strlcpy(spacestart, execi->execname, PATH_MAX);
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/* What will the address of the string for the user be */
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userp = *newsp + (spacestart-frame);
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/* Move back to where the AT_NULL is */
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a = term;
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AUXINFO(AT_SUN_EXECNAME, userp);
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AUXINFO(AT_NULL, 0);
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}
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return OK;
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}
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/*===========================================================================*
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* is_script *
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*===========================================================================*/
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static int is_script(struct vfs_exec_info *execi)
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{
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/* Is Interpreted script? */
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assert(execi->args.hdr != NULL);
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return(execi->args.hdr[0] == '#' && execi->args.hdr[1] == '!'
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&& execi->args.hdr_len >= 2);
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}
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/*===========================================================================*
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* patch_stack *
|
|
*===========================================================================*/
|
|
static int patch_stack(vp, stack, stk_bytes, path)
|
|
struct vnode *vp; /* pointer for open script file */
|
|
char stack[ARG_MAX]; /* pointer to stack image within VFS */
|
|
size_t *stk_bytes; /* size of initial stack */
|
|
char path[PATH_MAX]; /* path to script file */
|
|
{
|
|
/* Patch the argument vector to include the path name of the script to be
|
|
* interpreted, and all strings on the #! line. Returns the path name of
|
|
* the interpreter.
|
|
*/
|
|
enum { INSERT=FALSE, REPLACE=TRUE };
|
|
int n, r;
|
|
off_t pos;
|
|
char *sp, *interp = NULL;
|
|
u64_t new_pos;
|
|
unsigned int cum_io;
|
|
char buf[_MAX_BLOCK_SIZE];
|
|
|
|
/* Make 'path' the new argv[0]. */
|
|
if (!insert_arg(stack, stk_bytes, path, REPLACE)) return(ENOMEM);
|
|
|
|
pos = 0; /* Read from the start of the file */
|
|
|
|
/* Issue request */
|
|
r = req_readwrite(vp->v_fs_e, vp->v_inode_nr, cvul64(pos), READING,
|
|
VFS_PROC_NR, buf, _MAX_BLOCK_SIZE, &new_pos, &cum_io);
|
|
if (r != OK) return(r);
|
|
|
|
n = vp->v_size;
|
|
if (n > _MAX_BLOCK_SIZE)
|
|
n = _MAX_BLOCK_SIZE;
|
|
if (n < 2) return ENOEXEC;
|
|
|
|
sp = &(buf[2]); /* just behind the #! */
|
|
n -= 2;
|
|
if (n > PATH_MAX) n = PATH_MAX;
|
|
|
|
/* Use the 'path' variable for temporary storage */
|
|
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 *
|
|
*===========================================================================*/
|
|
static int insert_arg(
|
|
char stack[ARG_MAX], /* pointer to stack image within PM */
|
|
size_t *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;
|
|
vir_bytes a0, a1;
|
|
size_t 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);
|
|
|
|
strlcpy(stack + a0, arg, PATH_MAX); /* 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. */
|
|
libexec_patch_ptr(stack, (vir_bytes) offset);
|
|
((char **) stack)[1] = (char *) a0; /* set argv[0] correctly */
|
|
return(TRUE);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* read_seg *
|
|
*===========================================================================*/
|
|
static int read_seg(struct exec_info *execi, off_t off, off_t seg_addr, size_t seg_bytes)
|
|
{
|
|
/*
|
|
* 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;
|
|
u64_t new_pos;
|
|
unsigned int cum_io;
|
|
struct vnode *vp = ((struct vfs_exec_info *) execi->opaque)->vp;
|
|
|
|
/* Make sure that the file is big enough */
|
|
if (off + seg_bytes > LONG_MAX) return(EIO);
|
|
if ((unsigned long) vp->v_size < off+seg_bytes) return(EIO);
|
|
|
|
if ((r = req_readwrite(vp->v_fs_e, vp->v_inode_nr, cvul64(off), READING,
|
|
execi->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\n");
|
|
|
|
return(r);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* clo_exec *
|
|
*===========================================================================*/
|
|
static 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 *
|
|
*===========================================================================*/
|
|
static int map_header(struct vfs_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 */
|
|
|
|
/* How much is sensible to read */
|
|
execi->args.hdr_len = MIN(execi->vp->v_size, sizeof(hdr));
|
|
execi->args.hdr = hdr;
|
|
|
|
r = req_readwrite(execi->vp->v_fs_e, execi->vp->v_inode_nr,
|
|
cvul64(pos), READING, VFS_PROC_NR, hdr,
|
|
execi->args.hdr_len, &new_pos, &cum_io);
|
|
if (r != OK) {
|
|
printf("VFS: exec: map_header: req_readwrite failed\n");
|
|
return(r);
|
|
}
|
|
|
|
return(OK);
|
|
}
|