Fix crash when AGWPE connection attempt times out #622
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When a connection attempt via AGWPE had exhausted all retries, Direwolf would crash (segfault) on Linux. This happened because the timer expiry check (dl_timer_expiry) iterates over the state machine list in a way that assumes the list is not modified during iteration. However, recent changes to clean up AGWPE connections violated this assumption, such that a state machine might be removed from the list during iteration. Updating the iterations was missed in those earlier changes. This change replaces the loop structure with one that allows for the modification of the list during iteration. Currently t1_expiry() is the only case in which the list may be modified; however, t3_expiry() and tm201_expiry() loops have also been changed to insure against possible future modifications. Fixes wb2osz#621
wb2osz
approved these changes
Nov 10, 2025
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When a connection attempt via AGWPE had exhausted all retries, Direwolf would crash (segfault) on Linux. This happened because the timer expiry check (dl_timer_expiry) iterates over the state machine list in a way that assumes the list is not modified during iteration. However, recent changes to clean up AGWPE connections violated this assumption, such that a state machine might be removed from the list during iteration. Updating the iterations was missed in those earlier changes.
This change replaces the loop structure with one that allows for the modification of the list during iteration. Currently t1_expiry() is the only case in which the list may be modified; however, t3_expiry() and tm201_expiry() loops have also been changed to insure against possible future modifications.
Fixes #621