zdb: Silence Coverity complaint about verify_livelist_allocs()

svb is declared on the stack. We then set parts of svb.svb_dva with
DVA_SET_VDEV(), DVA_SET_OFFSET() and DVA_SET_ASIZE(). However, the DVA
contains other fields for pad, GRID and G. When setting the fields we
use, we technically read uninitialized bits  from the fields we do not
use. This makes Coverity and Clang's Static Analyzer complain.
Presumably, other static analyzers might complain too.

There is no real bug here, but we are still technically reading
undefined data and unless we stop doing that, static analyzers will
complain about it in perpetuum and this could obscure real issues. We
silence the static analyzer complaints by using a 0 struct initializer.

Reported by: Coverity (CID 1524627)
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14210
This commit is contained in:
Richard Yao 2022-11-16 16:23:53 -05:00 committed by Brian Behlendorf
parent 8532da5e20
commit 887fb37843
1 changed files with 1 additions and 1 deletions

View File

@ -468,7 +468,7 @@ static void
verify_livelist_allocs(metaslab_verify_t *mv, uint64_t txg, verify_livelist_allocs(metaslab_verify_t *mv, uint64_t txg,
uint64_t offset, uint64_t size) uint64_t offset, uint64_t size)
{ {
sublivelist_verify_block_t svb; sublivelist_verify_block_t svb = {{{0}}};
DVA_SET_VDEV(&svb.svb_dva, mv->mv_vdid); DVA_SET_VDEV(&svb.svb_dva, mv->mv_vdid);
DVA_SET_OFFSET(&svb.svb_dva, offset); DVA_SET_OFFSET(&svb.svb_dva, offset);
DVA_SET_ASIZE(&svb.svb_dva, size); DVA_SET_ASIZE(&svb.svb_dva, size);