fix(exr): use rectangle row stride for partial edge tile reads - #5295
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read_native_tiles() on a tiled EXR whose dimensions aren't a multiple of the tile size wrote past the caller's buffer when reading an edge tile range: both readers used a row stride padded up to a whole number of tiles (nxtiles*tile_width) instead of the caller's actual rectangle width, overrunning the buffer whenever the last tile column is partial. Fixed in both exrinput_c.cpp (Core reader) and exrinput.cpp (classic reader) to use the requested rectangle width as the destination row stride instead. exrinput.cpp additionally needs the pre-clamp width specifically, since read_native_tile() forwards a tile-aligned xend past the image edge for ordinary full-tile reads. Adds testsuite/openexr-partialtile, a compiled regression test that calls read_native_tiles() directly for both readers -- the only path that exercises this code -- and checks pixels and buffer bounds. Assisted-by: Claude Code / Claude Opus 4.8 Signed-off-by: Larry Gritz <lg@larrygritz.com>
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Any comments or concerns about this one? |
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Nearly two weeks old, no objections -> merging. |
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CVE-2026-63422 |
lgritz
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…mySoftwareFoundation#5295) read_native_tiles() on a tiled EXR whose dimensions aren't a multiple of the tile size wrote past the caller's buffer when reading an edge tile range: both readers used a row stride padded up to a whole number of tiles (nxtiles*tile_width) instead of the caller's actual rectangle width, overrunning the buffer whenever the last tile column is partial. Fixed in both exrinput_c.cpp (Core reader) and exrinput.cpp (classic reader) to use the requested rectangle width as the destination row stride instead. exrinput.cpp additionally needs the pre-clamp width specifically, since read_native_tile() forwards a tile-aligned xend past the image edge for ordinary full-tile reads. Adds testsuite/openexr-partialtile, a compiled regression test that calls read_native_tiles() directly for both readers -- the only path that exercises this code -- and checks pixels and buffer bounds. Assisted-by: Claude Code / Claude Opus 4.8 Signed-off-by: Larry Gritz <lg@larrygritz.com>
lgritz
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Jul 22, 2026
…mySoftwareFoundation#5295) read_native_tiles() on a tiled EXR whose dimensions aren't a multiple of the tile size wrote past the caller's buffer when reading an edge tile range: both readers used a row stride padded up to a whole number of tiles (nxtiles*tile_width) instead of the caller's actual rectangle width, overrunning the buffer whenever the last tile column is partial. Fixed in both exrinput_c.cpp (Core reader) and exrinput.cpp (classic reader) to use the requested rectangle width as the destination row stride instead. exrinput.cpp additionally needs the pre-clamp width specifically, since read_native_tile() forwards a tile-aligned xend past the image edge for ordinary full-tile reads. Adds testsuite/openexr-partialtile, a compiled regression test that calls read_native_tiles() directly for both readers -- the only path that exercises this code -- and checks pixels and buffer bounds. Assisted-by: Claude Code / Claude Opus 4.8 Signed-off-by: Larry Gritz <lg@larrygritz.com>
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read_native_tiles() on a tiled EXR whose dimensions aren't a multiple of the tile size wrote past the caller's buffer when reading an edge tile range: both readers used a row stride padded up to a whole number of tiles (nxtiles*tile_width) instead of the caller's actual rectangle width, overrunning the buffer whenever the last tile column is partial.
Fixed in both exrinput_c.cpp (Core reader) and exrinput.cpp (classic reader) to use the requested rectangle width as the destination row stride instead. exrinput.cpp additionally needs the pre-clamp width specifically, since read_native_tile() forwards a tile-aligned xend past the image edge for ordinary full-tile reads.
Adds testsuite/openexr-partialtile, a compiled regression test that calls read_native_tiles() directly for both readers -- the only path that exercises this code -- and checks pixels and buffer bounds.
Assisted-by: Claude Code / Claude Opus 4.8