From cb36f4f3529473d977189010f41b9a98c644d2d3 Mon Sep 17 00:00:00 2001 From: Rob Norris Date: Tue, 23 Jul 2024 11:43:18 +1000 Subject: [PATCH] zstream recompress: fix zero recompressed buffer and output If compression happend, any garbage past the compress size was not zeroed out. If compression didn't happen, then the payload size was still set to the rounded-up return from zio_compress_data(), which is dependent on the input, which is not necessarily the logical size. So that's all fixed too, mostly from stealing the math from zio.c. Sponsored-by: Klara, Inc. Sponsored-by: Wasabi Technology, Inc. Signed-off-by: Rob Norris --- cmd/zstream/zstream_recompress.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/cmd/zstream/zstream_recompress.c b/cmd/zstream/zstream_recompress.c index 32ef6fa544..ae2c56320b 100644 --- a/cmd/zstream/zstream_recompress.c +++ b/cmd/zstream/zstream_recompress.c @@ -287,24 +287,26 @@ zstream_do_recompress(int argc, char *argv[]) dbuf, drrw->drr_logical_size); abd_t *pabd = abd_get_from_buf_struct(&abd, buf, bufsz); - payload_size = P2ROUNDUP(zio_compress_data( - ctype, &dabd, &pabd, - drrw->drr_logical_size, level), - SPA_MINBLOCKSIZE); - if (payload_size != drrw->drr_logical_size) { - drrw->drr_compressiontype = ctype; - drrw->drr_compressed_size = - payload_size; - } else { + size_t csize = zio_compress_data(ctype, &dabd, + &pabd, drrw->drr_logical_size, level); + size_t rounded = + P2ROUNDUP(csize, SPA_MINBLOCKSIZE); + if (rounded >= drrw->drr_logical_size) { memcpy(buf, dbuf, payload_size); drrw->drr_compressiontype = 0; drrw->drr_compressed_size = 0; + } else { + abd_zero_off(pabd, csize, + rounded - csize); + drrw->drr_compressiontype = ctype; + drrw->drr_compressed_size = + payload_size = rounded; } abd_free(&abd); abd_free(&dabd); free(dbuf); } else { - drrw->drr_compressiontype = ctype; + drrw->drr_compressiontype = 0; drrw->drr_compressed_size = 0; } break;