From f0cfce64b6a061ffeafeda254734f0b1f2f452fd Mon Sep 17 00:00:00 2001 From: Steve Vinoski Date: Sun, 1 Mar 2015 12:33:20 -0500 Subject: Ensure NIF term creation disallows illegal values Add a check to enif_make_double to see if its double argument is infinity or NaN, returning a badarg exception if it is. Change the erl_nif documentation to specify that enif_make_double returns a badarg exception if its double argument is either infinity or NaN. Add tests to nif_SUITE for this change. Add checks to the enif_make* functions for atoms to prevent the creation of atoms whose name lengths are greater than the allowed maximum atom length. The enif_make_atom and enif_make_atom_len functions now return a badarg exception if the input string is too long. The enif_make_existing_atom and enif_make_existing_atom_len functions return false if the input string is too long. Change the erl_nif documentation to reflect the changes to these functions. Add tests to nif_SUITE for these changes. Add a field to ErlNifEnv to track that a NIF has raised an exception via enif_make_badarg. If a NIF calls enif_make_badarg but then ignores its return value and instead tries to return a non-exception term as its return value, the runtime still raises a badarg. This is needed to prevent enif_make_badarg values resulting from calls to enif_make_double, enif_make_atom, or enif_make_atom_len from being erroneously stored within other terms and returned from a NIF. Calling enif_make_badarg but not returning its return value has been documented as being illegal ever since enif_make_badarg was added, but the runtime has not enforced it until now. Add tests for regular and dirty NIFs to ensure that calls to enif_make_badarg result in badarg exceptions even if a NIF fails to return the result of enif_make_badarg as its return value. Add documentation to enif_make_badarg to specify that calling it raises a badarg even if a NIF ignores its return value. --- erts/emulator/beam/beam_emu.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'erts/emulator/beam/beam_emu.c') diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c index 8bfb7d2ad2..d352528059 100644 --- a/erts/emulator/beam/beam_emu.c +++ b/erts/emulator/beam/beam_emu.c @@ -3523,6 +3523,8 @@ get_map_elements_fail: erts_pre_nif(&env, c_p, (struct erl_module_nif*)I[2]); reg[0] = r(0); nif_bif_result = (*fp)(&env, bif_nif_arity, reg); + if (env.exception_thrown) + nif_bif_result = THE_NON_VALUE; erts_post_nif(&env); } ASSERT(!ERTS_PROC_IS_EXITING(c_p) || is_non_value(nif_bif_result)); -- cgit v1.2.3