Fix UB issue which can be caused by not init proto_len before reading it#961
Merged
normanmaurer merged 1 commit intomainfrom Mar 23, 2026
Merged
Fix UB issue which can be caused by not init proto_len before reading it#961normanmaurer merged 1 commit intomainfrom
normanmaurer merged 1 commit intomainfrom
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Motivation: We failed to initialize proto_len and so could end up to undefined behavior. Modifications: - proto_len is now initialized to 0 — eliminating the undefined behaviour from reading it uninitialized. - The CHOOSE_MY_LAST_PROTOCOL branch is now guarded with proto != NULL — if the peer sent no protocols (inlen == 0) the inner loop never runs and proto stays NULL, so we correctly fall through to SSL_TLSEXT_ERR_NOACK instead of doing arithmetic on a null/garbage pointer. Result: Fix UB
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Motivation:
We failed to initialize proto_len and so could end up to undefined behavior.
Modifications:
so we correctly fall through to SSL_TLSEXT_ERR_NOACK instead of doing arithmetic on a null/garbage pointer.
Result:
Fix UB