libssh2_userauth_keyboard_interactive_ex callback and memory allocation #1078
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bagder
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Jun 1, 2023
Because of how libssh2_userauth_keyboard_interactive_ex() works: the libcurl callback allocates memory that is later free()d by libssh2, we must set the custom memory functions. Reverts 8b5f100 Ref: libssh2/libssh2#1078
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It's surely confusing and non-obvious, but unless we want to change the API to never free() or return allocated pointers (to be freed by callers), we might make this gotcha clearer in the docs. |
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Yeah, I don't think we can fix this without adding a replacement function, and until someone wants to work on that I think clarifying this caveat in the documentation is the next best thing. At least there is a functioning workaround! |
bagder
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Jun 1, 2023
Because of how libssh2_userauth_keyboard_interactive_ex() works: the libcurl callback allocates memory that is later free()d by libssh2, we must set the custom memory functions. Reverts 8b5f100 Ref: libssh2/libssh2#1078 Closes #11235
bch
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Jul 19, 2023
Because of how libssh2_userauth_keyboard_interactive_ex() works: the libcurl callback allocates memory that is later free()d by libssh2, we must set the custom memory functions. Reverts 8b5f100 Ref: libssh2/libssh2#1078 Closes curl#11235
ptitSeb
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Sep 25, 2023
Because of how libssh2_userauth_keyboard_interactive_ex() works: the libcurl callback allocates memory that is later free()d by libssh2, we must set the custom memory functions. Reverts 8b5f100 Ref: libssh2/libssh2#1078 Closes curl#11235
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Describe the bug
The function
libssh2_userauth_keyboard_interactive_excalls a function in the app to return a set of passwords.These passwords are documented as:
String values will be free(3)ed by the library.This is a problem on (for example) Windows when libssh2 is used as a DLL, as then they use memory models that cannot be shared between an application and the DLL.
This happens on git master and this issue has probably always existed. It can be circumvented by providing custom memory functions using
libssh2_session_init_ex.The text was updated successfully, but these errors were encountered: