diff options
| -rw-r--r-- | fs/bcachefs/compress.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/fs/bcachefs/compress.c b/fs/bcachefs/compress.c index 27bbc265d550..78757dcede36 100644 --- a/fs/bcachefs/compress.c +++ b/fs/bcachefs/compress.c @@ -336,8 +336,19 @@ static int attempt_compress(struct bch_fs *c, ZSTD_CCtx *ctx = zstd_init_cctx(workspace, zstd_cctx_workspace_bound(&c->zstd_params.cParams)); + /* + * ZSTD requires that when we decompress we pass in the exact + * compressed size - rounding it up to the nearest sector + * doesn't work, so we use the first 4 bytes of the buffer for + * that. + * + * Additionally, the ZSTD code seems to have a bug where it will + * write just past the end of the buffer - so subtract a fudge + * factor (7 bytes) from the dst buffer size to account for + * that. + */ size_t len = zstd_compress_cctx(ctx, - dst + 4, dst_len - 4, + dst + 4, dst_len - 4 - 7, src, src_len, &c->zstd_params); if (zstd_is_error(len)) |