on MIPS64 we have "ZZZZZZZZ" instead of "/bin/sh", for example:
https://people.freebsd.org/~br/kyua_mips/bin_cat_cat_test_align.html
Using strdup helps
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jmmv - Group Reviewers
tests - Commits
- rS306440: Fix conversion from C++ std::string into C const char *.
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it comes from conversion from C++ std::string to C const char * using c_str()
This C++ function returns the correct value "/bin/sh":
std::string
impl::get(const std::string& name, const std::string& default_value)
{
const char *a;
a = atf_env_get_with_default(name.c_str(), default_value.c_str());
printf("a is %s\n", a);
return (a);}
but then we converting it to C using c_str() here:
sh_argv[0] = atf::env::get("ATF_SHELL", ATF_SHELL).c_str();
and it gets to ZZZZZZZZZ
We use GCC 4.2.1 on MIPS, may be this is a reason ?
The only strdup() helps for me
| contrib/atf/atf-sh/atf-check.cpp | ||
|---|---|---|
| 351 | The original code is bogus because this statement is constructing a temporary std::string and getting a pointer to its contents. When the assignment is complete, the temporary std::string is destroyed so the pointer is invalid. I guess that the STL in your platform (or something else, who knows) is being compiled with a debug option that is zeroing out (with Zs) the std::string's contents to spot this use-after-free issue. If you do the following right after the assignment of "cmd": const std::string shell = atf::env::get("ATF_SHELL", ATF_SHELL).c_str(); then you can do: sh_argv[0] = shell.c_str(); I bet this will work, and is better than the strdup hack. | |
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Note that this is not a workaround: this is a proper fix for broken code.
| contrib/atf/atf-sh/atf-check.cpp | ||
|---|---|---|
| 351 | For style reasons, please move this to right after line 348, as I previously said. | |
| contrib/atf/atf-sh/atf-check.cpp | ||
|---|---|---|
| 349 | Remove the c_str() from here, or else you are creating an extra string for no reason. | |