Ticket History #8846: Fix SPNEGO fallback context handling

Fix SPNEGO fallback context handling

In init_ctx_call_init(), if gss_init_sec_context() fails while
producing the first SPNEGO initiator token, we remove the first
candidate mechanism from sc->mech_set and try again. If
sc->ctx_handle is present after the error (more likely after commit
56f7b1bc95a2a3eeb420e069e7655fb181ade5cf), we must clear it before
falling back or it will cause subsequent attempts to fail.

(cherry picked from commit 40ecfad10dd36700028ff0f3d0d79ce7925fe545)

https://github.com/krb5/krb5/commit/e72efb781a8fcf6a8fb9d2db17cd81a01ed489e2
Author: Greg Hudson <ghudson@mit.edu>
Commit: e72efb781a8fcf6a8fb9d2db17cd81a01ed489e2
Branch: krb5-1.16
src/lib/gssapi/spnego/spnego_mech.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)

Fix SPNEGO fallback context handling

In init_ctx_call_init(), if gss_init_sec_context() fails while
producing the first SPNEGO initiator token, we remove the first
candidate mechanism from sc->mech_set and try again. If
sc->ctx_handle is present after the error (more likely after commit
56f7b1bc95a2a3eeb420e069e7655fb181ade5cf), we must clear it before
falling back or it will cause subsequent attempts to fail.

(cherry picked from commit 40ecfad10dd36700028ff0f3d0d79ce7925fe545)

https://github.com/krb5/krb5/commit/206edea3b1e10bfef331d7e03dcb1e1b55c40d79
Author: Greg Hudson <ghudson@mit.edu>
Commit: 206edea3b1e10bfef331d7e03dcb1e1b55c40d79
Branch: krb5-1.17
src/lib/gssapi/spnego/spnego_mech.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)