[Libguestfs] [PATCH 1/4] common/mlpcre: Raise Invalid_argument if PCRE.sub n parameter is negative.

--- common/mlpcre/pcre-c.c | 7 +++++-- common/mlpcre/pcre_tests.ml | 7 +++++++ 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/common/mlpcre/pcre-c.c b/common/mlpcre/pcre-c.c index 6fae0e6f4..da9b50d34 100644 --- a/common/mlpcre/pcre-c.c +++ b/common/mlpcre/pcre-c.c @@ -201,6 +201,7 @@ value guestfs_int_pcre_sub (value nv) { CAMLparam1 (nv); + int n = Int_val (nv); CAMLlocal1 (strv); int len; CLEANUP_FREE char *str = NULL; @@ -209,8 +210,10 @@ guestfs_int_pcre_sub (value nv) if (m == NULL) raise_pcre_error ("PCRE.sub called without calling PCRE.matches", 0); - len = pcre_get_substring (m->subject, m->vec, m->r, Int_val (nv), - (const char **) &str); + if (n < 0) + caml_invalid_argument ("PCRE.sub: n must be >= 0"); + + len = pcre_get_substring (m->subject, m->vec, m->r, n, (const char **) &str); if (len == PCRE_ERROR_NOSUBSTRING) caml_raise_not_found (); diff --git a/common/mlpcre/pcre_tests.ml b/common/mlpcre/pcre_tests.ml index e5214eab8..2b18f462f 100644 --- a/common/mlpcre/pcre_tests.ml +++ b/common/mlpcre/pcre_tests.ml @@ -69,6 +69,13 @@ let () = | PCRE.Error (msg, code) -> failwith (sprintf "PCRE error: %s (PCRE error code %d)" msg code) +(* Run some out of range [sub] calls to ensure an exception is thrown. *) +let () = + let re2 = compile "(a+)(b*)" in + ignore (matches re2 "ccac"); + (try ignore (sub 3) with Not_found -> ()); + (try ignore (sub (-1)) with Invalid_argument _ -> ()) + (* Compile some bad regexps and check that an exception is thrown. * It would be nice to check the error message is right but * that involves dealing with language and future changes of -- 2.13.2