Revert "exec: load_script: don't blindly truncate shebang string"

This reverts commit 8099b047ec.

It turns out that people do actually depend on the shebang string being
truncated, and on the fact that an interpreter (like perl) will often
just re-interpret it entirely to get the full argument list.

Reported-by: Samuel Dionne-Riel <samuel@dionne-riel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Linus Torvalds 2019-02-14 15:02:18 -08:00
parent 23e93c9b2c
commit cb5b020a8d
1 changed files with 3 additions and 7 deletions

View File

@ -42,14 +42,10 @@ static int load_script(struct linux_binprm *bprm)
fput(bprm->file);
bprm->file = NULL;
for (cp = bprm->buf+2;; cp++) {
if (cp >= bprm->buf + BINPRM_BUF_SIZE)
return -ENOEXEC;
if (!*cp || (*cp == '\n'))
break;
}
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'))