Annotation of qemu/linux-user/linuxload.c, revision 1.1.1.9

1.1.1.3   root        1: /* Code for loading Linux executables.  Mostly linux kernel code.  */
1.1       root        2: 
                      3: #include <sys/types.h>
                      4: #include <sys/stat.h>
                      5: #include <fcntl.h>
                      6: #include <errno.h>
                      7: #include <unistd.h>
                      8: #include <stdio.h>
                      9: #include <stdlib.h>
                     10: 
                     11: #include "qemu.h"
                     12: 
                     13: #define NGROUPS 32
                     14: 
                     15: /* ??? This should really be somewhere else.  */
1.1.1.3   root       16: abi_long memcpy_to_target(abi_ulong dest, const void *src,
                     17:                           unsigned long len)
1.1       root       18: {
                     19:     void *host_ptr;
                     20: 
1.1.1.3   root       21:     host_ptr = lock_user(VERIFY_WRITE, dest, len, 0);
                     22:     if (!host_ptr)
                     23:         return -TARGET_EFAULT;
1.1       root       24:     memcpy(host_ptr, src, len);
                     25:     unlock_user(host_ptr, dest, 1);
1.1.1.3   root       26:     return 0;
1.1       root       27: }
                     28: 
                     29: static int count(char ** vec)
                     30: {
                     31:     int                i;
                     32: 
                     33:     for(i = 0; *vec; i++) {
                     34:         vec++;
                     35:     }
                     36: 
                     37:     return(i);
                     38: }
                     39: 
                     40: static int prepare_binprm(struct linux_binprm *bprm)
                     41: {
                     42:     struct stat                st;
                     43:     int mode;
1.1.1.8   root       44:     int retval;
1.1       root       45: 
                     46:     if(fstat(bprm->fd, &st) < 0) {
                     47:        return(-errno);
                     48:     }
                     49: 
                     50:     mode = st.st_mode;
                     51:     if(!S_ISREG(mode)) {       /* Must be regular file */
                     52:        return(-EACCES);
                     53:     }
                     54:     if(!(mode & 0111)) {       /* Must have at least one execute bit set */
                     55:        return(-EACCES);
                     56:     }
                     57: 
                     58:     bprm->e_uid = geteuid();
                     59:     bprm->e_gid = getegid();
                     60: 
                     61:     /* Set-uid? */
                     62:     if(mode & S_ISUID) {
                     63:        bprm->e_uid = st.st_uid;
                     64:     }
                     65: 
                     66:     /* Set-gid? */
                     67:     /*
                     68:      * If setgid is set but no group execute bit then this
                     69:      * is a candidate for mandatory locking, not a setgid
                     70:      * executable.
                     71:      */
                     72:     if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
                     73:        bprm->e_gid = st.st_gid;
                     74:     }
                     75: 
1.1.1.7   root       76:     retval = read(bprm->fd, bprm->buf, BPRM_BUF_SIZE);
                     77:     if (retval < 0) {
1.1       root       78:        perror("prepare_binprm");
                     79:        exit(-1);
                     80:     }
1.1.1.7   root       81:     if (retval < BPRM_BUF_SIZE) {
                     82:         /* Make sure the rest of the loader won't read garbage.  */
                     83:         memset(bprm->buf + retval, 0, BPRM_BUF_SIZE - retval);
1.1       root       84:     }
1.1.1.7   root       85:     return retval;
1.1       root       86: }
                     87: 
                     88: /* Construct the envp and argv tables on the target stack.  */
1.1.1.3   root       89: abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
                     90:                               abi_ulong stringp, int push_ptr)
1.1       root       91: {
1.1.1.4   root       92:     TaskState *ts = (TaskState *)thread_env->opaque;
1.1.1.3   root       93:     int n = sizeof(abi_ulong);
                     94:     abi_ulong envp;
                     95:     abi_ulong argv;
1.1       root       96: 
                     97:     sp -= (envc + 1) * n;
                     98:     envp = sp;
                     99:     sp -= (argc + 1) * n;
                    100:     argv = sp;
                    101:     if (push_ptr) {
1.1.1.3   root      102:         /* FIXME - handle put_user() failures */
                    103:         sp -= n;
                    104:         put_user_ual(envp, sp);
                    105:         sp -= n;
                    106:         put_user_ual(argv, sp);
                    107:     }
                    108:     sp -= n;
                    109:     /* FIXME - handle put_user() failures */
                    110:     put_user_ual(argc, sp);
1.1.1.4   root      111:     ts->info->arg_start = stringp;
1.1       root      112:     while (argc-- > 0) {
1.1.1.3   root      113:         /* FIXME - handle put_user() failures */
                    114:         put_user_ual(stringp, argv);
                    115:         argv += n;
1.1       root      116:         stringp += target_strlen(stringp) + 1;
                    117:     }
1.1.1.4   root      118:     ts->info->arg_end = stringp;
1.1.1.3   root      119:     /* FIXME - handle put_user() failures */
                    120:     put_user_ual(0, argv);
1.1       root      121:     while (envc-- > 0) {
1.1.1.3   root      122:         /* FIXME - handle put_user() failures */
                    123:         put_user_ual(stringp, envp);
                    124:         envp += n;
1.1       root      125:         stringp += target_strlen(stringp) + 1;
                    126:     }
1.1.1.3   root      127:     /* FIXME - handle put_user() failures */
                    128:     put_user_ual(0, envp);
1.1       root      129: 
                    130:     return sp;
                    131: }
                    132: 
1.1.1.3   root      133: int loader_exec(const char * filename, char ** argv, char ** envp,
1.1.1.4   root      134:              struct target_pt_regs * regs, struct image_info *infop,
                    135:              struct linux_binprm *bprm)
1.1       root      136: {
                    137:     int retval;
                    138:     int i;
                    139: 
1.1.1.4   root      140:     bprm->p = TARGET_PAGE_SIZE*MAX_ARG_PAGES-sizeof(unsigned int);
1.1.1.7   root      141:     memset(bprm->page, 0, sizeof(bprm->page));
1.1       root      142:     retval = open(filename, O_RDONLY);
                    143:     if (retval < 0)
                    144:         return retval;
1.1.1.4   root      145:     bprm->fd = retval;
                    146:     bprm->filename = (char *)filename;
                    147:     bprm->argc = count(argv);
                    148:     bprm->argv = argv;
                    149:     bprm->envc = count(envp);
                    150:     bprm->envp = envp;
1.1       root      151: 
1.1.1.4   root      152:     retval = prepare_binprm(bprm);
1.1       root      153: 
                    154:     if(retval>=0) {
1.1.1.4   root      155:         if (bprm->buf[0] == 0x7f
                    156:                 && bprm->buf[1] == 'E'
                    157:                 && bprm->buf[2] == 'L'
                    158:                 && bprm->buf[3] == 'F') {
1.1.1.6   root      159:             retval = load_elf_binary(bprm, regs, infop);
1.1       root      160: #if defined(TARGET_HAS_BFLT)
1.1.1.4   root      161:         } else if (bprm->buf[0] == 'b'
                    162:                 && bprm->buf[1] == 'F'
                    163:                 && bprm->buf[2] == 'L'
                    164:                 && bprm->buf[3] == 'T') {
                    165:             retval = load_flt_binary(bprm,regs,infop);
1.1       root      166: #endif
                    167:         } else {
                    168:             fprintf(stderr, "Unknown binary format\n");
                    169:             return -1;
                    170:         }
                    171:     }
1.1.1.3   root      172: 
1.1       root      173:     if(retval>=0) {
                    174:         /* success.  Initialize important registers */
                    175:         do_init_thread(regs, infop);
                    176:         return retval;
                    177:     }
                    178: 
                    179:     /* Something went wrong, return the inode and free the argument pages*/
                    180:     for (i=0 ; i<MAX_ARG_PAGES ; i++) {
1.1.1.9 ! root      181:         g_free(bprm->page[i]);
1.1       root      182:     }
                    183:     return(retval);
                    184: }

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