On 2004-10-02 03:52, Ryan Sommers <rya...@gamersimpact.com> wrote:

This might break things because the user hasn't specified -i and will suddenly get a prompt. Unexpected prompts might never get an answer.

I liked what Max Laier proposed though, about making this tunable and defaulting to off. See below for the behavior of what I've come up with:

On 2004-10-02 11:23, Max Laier <ma...@love2party.net> wrote:

Agreed. Thanks for the feedback. Positive replies are not the only sort that are worth a lot :-)

How does the following look instead of forcing stuff to the user?

1. Silently erroring out:

chroot# export RM_PROTECT_ROOT=1 chroot# /bin/rm -fr / chroot# echo $? 1 chroot# /bin/rm -fr .././ chroot# echo $? 1

2. Warning with an error message because RM_PROTECT_ROOT is set:

chroot# export RM_PROTECT_ROOT=1 chroot# /bin/rm -r / rm: recursive rm of / not allowed chroot# /bin/rm -r .././ rm: recursive rm of / not allowed

3. The current behavior as a default when RM_PROTECT_ROOT is unset:

chroot# unset RM_PROTECT_ROOT chroot# /bin/rm -r / override rwxr-xr-x 0/0 for /bin/rm? ^Cchroot# chroot# chroot# chroot# /bin/rm -fr / rm: /libexec/ld-elf.so.1: Operation not permitted rm: /libexec: Directory not empty rm: /lib/libc.so.5: Operation not permitted rm: /lib/libcrypt.so.2: Operation not permitted rm: /lib: Directory not empty rm: /: Is a directory chroot# ls -l ls: not found chroot# echo * lib libexec chroot# cd lib chroot# echo * libc.so.5 libcrypt.so.2 chroot# exit

Here's the updated diff:

%%% Index: rm.c =================================================================== RCS file: /home/ncvs/src/bin/rm/rm.c,v retrieving revision 1.47 diff -u -r1.47 rm.c --- rm.c 6 Apr 2004 20:06:50 -0000 1.47 +++ rm.c 2 Oct 2004 10:06:59 -0000 @@ -57,7 +57,7 @@ #include <sysexits.h> #include <unistd.h>

-int dflag, eval, fflag, iflag, Pflag, vflag, Wflag, stdin_ok; +int dflag, eval, fflag, iflag, Pflag, vflag, Wflag, stdin_ok, protect_root; uid_t uid;

int check(char *, char *, struct stat *); @@ -100,6 +100,10 @@ exit(eval); }

+ protect_root = 0; + if (getenv("RM_PROTECT_ROOT") != NULL) + protect_root = 1; + Pflag = rflag = 0; while ((ch = getopt(argc, argv, "dfiPRrvW")) != -1) switch(ch) { @@ -157,6 +161,8 @@ void rm_tree(char **argv) { + static char *rpath = NULL; + char **argv_tmp; FTS *fts; FTSENT *p; int needstat; @@ -164,6 +170,25 @@ int rval;

/* + * If enabled in the environment with RM_PROTECT_ROOT disable the + * ability to recursively remove the root directory. + */ + if (protect_root) { + if (rpath == NULL && + (rpath = malloc(PATH_MAX * sizeof(char))) == NULL) + err(1, "malloc"); + for (argv_tmp = argv; *argv_tmp != NULL; argv_tmp++) { + if (realpath(*argv_tmp, rpath) == NULL && + strcmp(rpath, "/") != 0) + continue; + if (fflag != 0) + exit (1); + else + errx(1, "recursive rm of / not allowed"); + } + } + + /* * Remove a file hierarchy. If forcing removal (-f), or interactive * (-i) or can't ask anyway (stdin_ok), don't stat the file. */ %%%