-
-
Notifications
You must be signed in to change notification settings - Fork 32.2k
bpo-34824: Fix a possible NULL pointer dereference in _ssl.c #9606
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
bpo-34824: Fix a possible NULL pointer dereference in _ssl.c #9606
Conversation
On failure, _PyBytes_Resize() will deallocate the bytes object and set "result" to NULL.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Good catch!
Please address the comment.
Modules/_ssl.c
Outdated
@@ -4712,7 +4712,6 @@ _ssl_MemoryBIO_read_impl(PySSLMemoryBIO *self, int len) | |||
nbytes = BIO_read(self->bio, PyBytes_AS_STRING(result), len); | |||
/* There should never be any short reads but check anyway. */ | |||
if ((nbytes < len) && (_PyBytes_Resize(&result, len) < 0)) { | |||
Py_DECREF(result); |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Let's rewrite the block to conform to the style of other _PyBytes_Resize
calls. There is no need to check the return value of _PyBytes_Resize
, because the function returns result
any way.
if (nbytes < len) {
_PyBytes_Resize(&result, len);
}
A Python core developer has requested some changes be made to your pull request before we can consider merging it. If you could please address their requests along with any other requests in other reviews from core developers that would be appreciated. Once you have made the requested changes, please leave a comment on this pull request containing the phrase |
I have made the requested changes; please review again. |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
The current code doesn't have any effect and errors in BIO_read()
are not handled.
Modules/_ssl.c
Outdated
Py_DECREF(result); | ||
return NULL; | ||
if (nbytes < len) { | ||
_PyBytes_Resize(&result, len); |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
This operation doesn't have any effect. There should be nbytes
instead of len
. Note that nbytes
can be negative, this denotes an error.
A Python core developer has requested some changes be made to your pull request before we can consider merging it. If you could please address their requests along with any other requests in other reviews from core developers that would be appreciated. Once you have made the requested changes, please leave a comment on this pull request containing the phrase |
I have made the requested changes; please review again. |
Thanks for making the requested changes! @serhiy-storchaka, @1st1, @tiran: please review the changes made to this pull request. |
if ((nbytes < len) && (_PyBytes_Resize(&result, len) < 0)) { | ||
Py_DECREF(result); | ||
if (nbytes < 0) { | ||
_setSSLError(NULL, 0, __FILE__, __LINE__); | ||
return NULL; |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
result
is leaked here.
I have made the requested changes; please review again. |
Thanks for making the requested changes! @tiran, @serhiy-storchaka, @1st1: please review the changes made to this pull request. |
Thanks @ZackerySpytz for the PR 🌮🎉.. I'm working now to backport this PR to: 3.6, 3.7. |
…H-9606) On failure, _PyBytes_Resize() will deallocate the bytes object and set "result" to NULL. https://bugs.python.org/issue34824 (cherry picked from commit 365ad2e) Co-authored-by: Zackery Spytz <[email protected]>
GH-9743 is a backport of this pull request to the 3.7 branch. |
…H-9606) On failure, _PyBytes_Resize() will deallocate the bytes object and set "result" to NULL. https://bugs.python.org/issue34824 (cherry picked from commit 365ad2e) Co-authored-by: Zackery Spytz <[email protected]>
GH-9744 is a backport of this pull request to the 3.6 branch. |
GH-9743) On failure, _PyBytes_Resize() will deallocate the bytes object and set "result" to NULL. https://bugs.python.org/issue34824 (cherry picked from commit 365ad2e) Co-authored-by: Zackery Spytz <[email protected]>
GH-9744) On failure, _PyBytes_Resize() will deallocate the bytes object and set "result" to NULL. https://bugs.python.org/issue34824 (cherry picked from commit 365ad2e) Co-authored-by: Zackery Spytz <[email protected]>
On failure, _PyBytes_Resize() will deallocate the bytes object and set
"result" to NULL.
https://bugs.python.org/issue34824