EbmlMaster: fix invalid reads#352
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We found an upper element and there is not data to read after the current element within its parent. That upper element is misplaced and should be discarded. The last element is truncated and doesn't contain the rest of its data.
When an element from an upper level is found we go up the caller chain, passing the found element but it was not actually used (added to a list or freed). This patch allows setting that element as the ElementLevelA found in the loop. We skip the call the inDataStream.FindNextElement() to find it. The new MaxSizeToRead is the size to read in the next inDataStream.FindNextElement() call. The old MaxSizeToRead <= 0 code seems bogus as it would exit the loop to find elements for that EbmlMaster even though there might still be elements to read.
…arent It could be a file with missing data in the middle. And we shouldn't use a MaxSizeToRead that would be negative. Missing backport to master Reported-by: Benjamin Ali (glitchfox) <glitchfox@benjaminali.com>
retokromer
approved these changes
Jul 23, 2026
mbunkus
approved these changes
Jul 24, 2026
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missing "backports" of #338, #341, and #322
Reported-by: Benjamin Ali (glitchfox) glitchfox@benjaminali.com