eal/windows: fix incorrect free condition in getopt implementation
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Commit Message
In the Windows getopt_internal function the condition freeing
the memory allocated by _dupenv_s is correct only for the first
call to the function.
the next callers will try to free the buffer even though the _dupenv_s
call is skipped if the POSIXLY_CORRECT env isn't found (undefined behavior).
Fixed by releasing the buffer in the scope of the same if statement calling _dupenv_s
Fixes: 5e373e456e6acdc ("eal/windows: add getopt implementation")
Cc: stable@dpdk.org
Signed-off-by: Tal Shnaiderman <talshn@nvidia.com>
---
lib/librte_eal/windows/getopt.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
Comments
On Wed, 23 Sep 2020 17:15:38 +0300, Tal Shnaiderman wrote:
> In the Windows getopt_internal function the condition freeing
> the memory allocated by _dupenv_s is correct only for the first
> call to the function.
Hi Tal,
a few days back Khoa To and me privately discussed a patch that makes MinGW
and Clang bith use getopt.c from librte_eal (now only Clang does). That patch
includes adjustments that just remove _dupenv_s() along with the bug. Just
discovered you were not Cc'd, sorry. I put your name in Reported-by and
mentioned the bug in commit message: http://patchwork.dpdk.org/patch/78765/
> From: Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>
> On Wed, 23 Sep 2020 17:15:38 +0300, Tal Shnaiderman wrote:
> > In the Windows getopt_internal function the condition freeing the
> > memory allocated by _dupenv_s is correct only for the first call to
> > the function.
>
> Hi Tal,
>
> a few days back Khoa To and me privately discussed a patch that makes
> MinGW and Clang bith use getopt.c from librte_eal (now only Clang does).
> That patch includes adjustments that just remove _dupenv_s() along with
> the bug. Just discovered you were not Cc'd, sorry. I put your name in
> Reported-by and mentioned the bug in commit message:
> https://nam11.safelinks.protection.outlook.com/?url=http%3A%2F%2Fpatch
> work.dpdk.org%2Fpatch%2F78765%2F&data=02%7C01%7Ctalshn%40nvi
> dia.com%7Cab3a10f2d2ec458a7ef908d860e00e69%7C43083d15727340c1b7db
> 39efd9ccc17a%7C0%7C0%7C637365862717871619&sdata=1xiI9JZ%2BUw
> sv2mj8rkAcff6%2B3KFNYZUiM72ZbnkyokY%3D&reserved=0
Thanks for the update Dmitry, I'll mark this commit as superseded.
@@ -253,16 +253,17 @@ getopt_internal(int nargc, char **nargv, const char *options,
* Disable GNU extensions if POSIXLY_CORRECT is set or options
* string begins with a '+'.
*/
- if (posixly_correct == -1)
+ if (posixly_correct == -1) {
posixly_correct = _dupenv_s(&buf, &len, "POSIXLY_CORRECT");
+ if (!posixly_correct)
+ free(buf);
+ }
if (!posixly_correct || *options == '+')
flags &= ~FLAG_PERMUTE;
else if (*options == '-')
flags |= FLAG_ALLARGS;
if (*options == '+' || *options == '-')
options++;
- if (!posixly_correct)
- free(buf);
/*
* reset if requested
*/