Fix GH-11020: spurious "Illegal IFD size" warning in exif_read_data()#22486
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eyupcanakman wants to merge 1 commit into
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Fix GH-11020: spurious "Illegal IFD size" warning in exif_read_data()#22486eyupcanakman wants to merge 1 commit into
eyupcanakman wants to merge 1 commit into
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When an IFD is not followed by a 4-byte next-IFD offset, the EXIF block has no further IFD. Treat that as the end of the chain and return the parsed tags, instead of warning and discarding them. The bounds check from bug #72094 still applies, so the absent offset bytes are never read.
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exif_read_data()emits a spurious "Illegal IFD size" warning on valid JPEGs whose EXIF block ends right after the IFD entries, with no next-IFD offset following them. The bounds check added for bug #72094 treats that absent offset as an error. A missing offset means there is no further IFD, so the fix returns the parsed tags instead of warning. cmb69 diagnosed this on the issue. The out-of-bounds read the check guards stays intact, because those bytes are never read.Adds a test, and confirms
bug72094.phptstill rejects the malformed inputs.