Fix stack buffer overflow in Schedule_Weekly_Schedule_Set#1222
Merged
skarg merged 2 commits intobacnet-stack:masterfrom Feb 7, 2026
Merged
Fix stack buffer overflow in Schedule_Weekly_Schedule_Set#1222skarg merged 2 commits intobacnet-stack:masterfrom
skarg merged 2 commits intobacnet-stack:masterfrom
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The memcpy was using sizeof(BACNET_WEEKLY_SCHEDULE) instead of sizeof(BACNET_DAILY_SCHEDULE), causing it to read 6784 bytes from a 968-byte source buffer, leading to stack buffer overflow and segmentation fault in the test_schedule unit test. This fixes the test_schedule test failure detected by ASAN: ERROR: AddressSanitizer: stack-buffer-overflow on address ... READ of size 6784 at 0x... partially underflows this variable Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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Pull request overview
Fixes a memory-safety bug in the Schedule object implementation by correcting the memcpy() size used when setting a single daily schedule entry within Schedule_Weekly_Schedule_Set().
Changes:
- Correct
memcpy()length fromsizeof(BACNET_WEEKLY_SCHEDULE)tosizeof(BACNET_DAILY_SCHEDULE)when copying one array element.
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skarg
approved these changes
Feb 7, 2026
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Summary
Fix stack buffer overflow in Schedule_Weekly_Schedule_Set() function.
Problem
The memcpy in Schedule_Weekly_Schedule_Set() was using sizeof(BACNET_WEEKLY_SCHEDULE) instead of sizeof(BACNET_DAILY_SCHEDULE). This caused it to read 6784 bytes from a 968-byte source
buffer, leading to:
Stack buffer overflow detected by AddressSanitizer
Segmentation fault in test_schedule unit test
Test failure: 99% tests passed, 1 test failed
Root Cause
Fix
Changed the memcpy size parameter from sizeof(BACNET_WEEKLY_SCHEDULE) to sizeof(BACNET_DAILY_SCHEDULE) since we are copying a single daily schedule element to the array at the specified
index.
Test Results
All 262 tests now pass (100%)
No AddressSanitizer errors
test_schedule test now passes
Checklist
Code compiles cleanly
All tests pass
Tested with AddressSanitizer - no memory errors
Follows project coding style