Fix size calculation in my_strlcat#3500
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ptitSeb merged 1 commit intoptitSeb:mainfrom Feb 12, 2026
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Previously, strncat was called with the total buffer size, ignoring the length of the existing string in 'dst'. This caused a buffer overflow when appending to a non-empty string. Fixed by passing 'remaining space' (total - current - 1) to strncat: strncat(dst, src, l-s-1); // Remaining space in buffer Also fix strlcpy off-by-one buffer overflow: dest[len-1]=0; // Write NUL within buffer bounds
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strncat was called with the total buffer size, ignoring the length of the existing string in 'dst'. This caused a buffer overflow when appending to a non-empty string.
Fixed by passing 'remaining space' (total - current - 1) to strncat:
strncat(dst, src, l-s-1); // Remaining space in buffer
Also fix strlcpy off-by-one buffer overflow:
dest[len-1]=0; // Write NUL within buffer bounds