cregit-Linux how code gets into the kernel

Release 4.9 fs/binfmt_script.c

Directory: fs
/*
 *  linux/fs/binfmt_script.c
 *
 *  Copyright (C) 1996  Martin von Löwis
 *  original #!-checking implemented by tytso.
 */

#include <linux/module.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/binfmts.h>
#include <linux/init.h>
#include <linux/file.h>
#include <linux/err.h>
#include <linux/fs.h>


static int load_script(struct linux_binprm *bprm) { const char *i_arg, *i_name; char *cp; struct file *file; char interp[BINPRM_BUF_SIZE]; int retval; if ((bprm->buf[0] != '#') || (bprm->buf[1] != '!')) return -ENOEXEC; /* * If the script filename will be inaccessible after exec, typically * because it is a "/dev/fd/<fd>/.." path against an O_CLOEXEC fd, give * up now (on the assumption that the interpreter will want to load * this file). */ if (bprm->interp_flags & BINPRM_FLAGS_PATH_INACCESSIBLE) return -ENOENT; /* * This section does the #! interpretation. * Sorta complicated, but hopefully it will work. -TYT */ allow_write_access(bprm->file); fput(bprm->file); bprm->file = NULL; bprm->buf[BINPRM_BUF_SIZE - 1] = '\0'; if ((cp = strchr(bprm->buf, '\n')) == NULL) cp = bprm->buf+BINPRM_BUF_SIZE-1; *cp = '\0'; while (cp > bprm->buf) { cp--; if ((*cp == ' ') || (*cp == '\t')) *cp = '\0'; else break; } for (cp = bprm->buf+2; (*cp == ' ') || (*cp == '\t'); cp++); if (*cp == '\0') return -ENOEXEC; /* No interpreter name found */ i_name = cp; i_arg = NULL; for ( ; *cp && (*cp != ' ') && (*cp != '\t'); cp++) /* nothing */ ; while ((*cp == ' ') || (*cp == '\t')) *cp++ = '\0'; if (*cp) i_arg = cp; strcpy (interp, i_name); /* * OK, we've parsed out the interpreter name and * (optional) argument. * Splice in (1) the interpreter's name for argv[0] * (2) (optional) argument to interpreter * (3) filename of shell script (replace argv[0]) * * This is done in reverse order, because of how the * user environment and arguments are stored. */ retval = remove_arg_zero(bprm); if (retval) return retval; retval = copy_strings_kernel(1, &bprm->interp, bprm); if (retval < 0) return retval; bprm->argc++; if (i_arg) { retval = copy_strings_kernel(1, &i_arg, bprm); if (retval < 0) return retval; bprm->argc++; } retval = copy_strings_kernel(1, &i_name, bprm); if (retval) return retval; bprm->argc++; retval = bprm_change_interp(interp, bprm); if (retval < 0) return retval; /* * OK, now restart the process with the interpreter's dentry. */ file = open_exec(interp); if (IS_ERR(file)) return PTR_ERR(file); bprm->file = file; retval = prepare_binprm(bprm); if (retval < 0) return retval; return search_binary_handler(bprm); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git40889.67%1266.67%
kees cookkees cook153.30%15.56%
david drysdaledavid drysdale132.86%15.56%
ollie wildollie wild91.98%15.56%
david howellsdavid howells51.10%15.56%
andrew mortonandrew morton40.88%15.56%
linus torvaldslinus torvalds10.22%15.56%
Total455100.00%18100.00%

static struct linux_binfmt script_format = { .module = THIS_MODULE, .load_binary = load_script, };
static int __init init_script_binfmt(void) { register_binfmt(&script_format); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git1583.33%375.00%
al viroal viro316.67%125.00%
Total18100.00%4100.00%


static void __exit exit_script_binfmt(void) { unregister_binfmt(&script_format); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git15100.00%2100.00%
Total15100.00%2100.00%

core_initcall(init_script_binfmt); module_exit(exit_script_binfmt); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git47286.61%1754.84%
kees cookkees cook152.75%13.23%
david drysdaledavid drysdale132.39%13.23%
dave jonesdave jones122.20%39.68%
ollie wildollie wild91.65%13.23%
andrew mortonandrew morton91.65%26.45%
david howellsdavid howells50.92%13.23%
art haasart haas40.73%13.23%
al viroal viro30.55%13.23%
linus torvaldslinus torvalds10.18%13.23%
jan engelhardtjan engelhardt10.18%13.23%
adrian bunkadrian bunk10.18%13.23%
Total545100.00%31100.00%
Directory: fs