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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-02-14 15:02:18 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-02-14 15:02:18 -0800 |
| commit | cb5b020a8d38f77209d0472a0fea755299a8ec78 (patch) | |
| tree | dd680d270410e8df9114ad98246e92c650291318 /fs/binfmt_script.c | |
| parent | 23e93c9b2cde73f9912d0d8534adbddd3dcc48f4 (diff) | |
| download | lwn-cb5b020a8d38f77209d0472a0fea755299a8ec78.tar.gz lwn-cb5b020a8d38f77209d0472a0fea755299a8ec78.zip | |
Revert "exec: load_script: don't blindly truncate shebang string"
This reverts commit 8099b047ecc431518b9bb6bdbba3549bbecdc343.
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>
Diffstat (limited to 'fs/binfmt_script.c')
| -rw-r--r-- | fs/binfmt_script.c | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/fs/binfmt_script.c b/fs/binfmt_script.c index d0078cbb718b..7cde3f46ad26 100644 --- a/fs/binfmt_script.c +++ b/fs/binfmt_script.c @@ -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')) |