kernel/linux.git/fs/erofs/decompressor_zstd.c, branch v6.12.81

erofs: avoid infinite loop due to incomplete zstd-compressed data

2025-11-24T09:35:49+00:00

[ Upstream commit f2a12cc3b97f062186568a7b94ddb7aa2ef68140 ] Currently, the decompression logic incorrectly spins if compressed data is truncated in crafted (deliberately corrupted) images. Fixes: 7c35de4df105 ("erofs: Zstandard compression support") Reported-by: Robert Morris Closes: https://lore.kernel.org/r/50958.1761605413@localhost Signed-off-by: Gao Xiang Reviewed-by: Chunhai Guo Reviewed-by: Chao Yu Signed-off-by: Sasha Levin

erofs: tidy up stream decompressors

2024-07-09T11:04:41+00:00

Just use a generic helper to prepare buffers for all supported stream decompressors, eliminating similar logic. Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20240709094106.3018109-3-hsiangkao@linux.alibaba.com

erofs: refine z_erofs_{init,exit}_subsystem()

2024-07-09T11:04:40+00:00

Introduce z_erofs_{init,exit}_decompressor() to unexport z_erofs_{deflate,lzma,zstd}_{init,exit}(). Besides, call them in z_erofs_{init,exit}_subsystem() for simplicity. Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20240709094106.3018109-2-hsiangkao@linux.alibaba.com

erofs: move each decompressor to its own source file

2024-07-09T11:04:40+00:00

Thus *_config() function declarations can be avoided. Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20240709094106.3018109-1-hsiangkao@linux.alibaba.com

erofs: Zstandard compression support

2024-05-08T23:46:56+00:00

Add Zstandard compression as the 4th supported algorithm since it becomes more popular now and some end users have asked this for quite a while [1][2]. Each EROFS physical cluster contains only one valid standard Zstandard frame as described in [3] so that decompression can be performed on a per-pcluster basis independently. Currently, it just leverages multi-call stream decompression APIs with internal sliding window buffers. One-shot or bufferless decompression could be implemented later for even better performance if needed. [1] https://github.com/erofs/erofs-utils/issues/6 [2] https://lore.kernel.org/r/Y08h+z6CZdnS1XBm@B-P7TQMD6M-0146.lan [3] https://www.rfc-editor.org/rfc/rfc8478.txt Acked-by: Chao Yu Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20240508234453.17896-1-xiang@kernel.org