Add `--enable-asan` and `--enable-ubsan` switches

`configure` now accepts `--enable-asan` and `--enable-ubsan` switches
which results in passing `-fsanitize=address`
and `-fsanitize=undefined`, respectively, to the compiler. Those
flags are enabled in GitHub workflows for ZTS and zloop. Errors
reported by both instrumentations are corrected, except for:

- Memory leak reporting is (temporarily) suppressed. The cost of
  fixing them is relatively high compared to the gains.

- Checksum computing functions in `module/zcommon/zfs_fletcher*`
  have UBSan errors suppressed. It is completely impractical
  to enforce 64-byte payload alignment there due to performance
  impact.

- There's no ASan heap poisoning in `module/zstd/lib/zstd.c`. A custom
  memory allocator is used there rendering that measure
  unfeasible.

- Memory leaks detection has to be suppressed for `cmd/zvol_id`.
  `zvol_id` is run by udev with the help of `ptrace(2)`. Tracing is
  incompatible with memory leaks detection.

Reviewed-by: Ahelenia Ziemiańska <[email protected]>
Reviewed-by: George Melikov <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: szubersk <[email protected]>
Closes #12928 

1 files changed, 2 insertions, 0 deletions

diff --git a/module/zcommon/zfs_fletcher_avx512.c b/module/zcommon/zfs_fletcher_avx512.c
index 963f089b0..8ee438ab9 100644
--- a/module/zcommon/zfs_fletcher_avx512.c
+++ b/module/zcommon/zfs_fletcher_avx512.c
@@ -35,12 +35,14 @@
 #define	__asm __asm__ __volatile__
 #endif
 
+ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_avx512f_init(fletcher_4_ctx_t *ctx)
 {
 	bzero(ctx->avx512, 4 * sizeof (zfs_fletcher_avx512_t));
 }
 
+ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_avx512f_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp)
 {