diff --git a/include/zfs_fletcher.h b/include/zfs_fletcher.h
index e913a0bd7..ca1a09292 100644
--- a/include/zfs_fletcher.h
+++ b/include/zfs_fletcher.h
@@ -76,19 +76,19 @@ typedef struct zfs_fletcher_superscalar {
 } zfs_fletcher_superscalar_t;
 
 typedef struct zfs_fletcher_sse {
-	uint64_t v[2] __attribute__((aligned(16)));
+	uint64_t v[2];
 } zfs_fletcher_sse_t;
 
 typedef struct zfs_fletcher_avx {
-	uint64_t v[4] __attribute__((aligned(32)));
+	uint64_t v[4];
 } zfs_fletcher_avx_t;
 
 typedef struct zfs_fletcher_avx512 {
-	uint64_t v[8] __attribute__((aligned(64)));
+	uint64_t v[8];
 } zfs_fletcher_avx512_t;
 
 typedef struct zfs_fletcher_aarch64_neon {
-	uint64_t v[2] __attribute__((aligned(16)));
+	uint64_t v[2];
 } zfs_fletcher_aarch64_neon_t;
 
 
@@ -161,20 +161,4 @@ _ZFS_FLETCHER_H const fletcher_4_ops_t fletcher_4_aarch64_neon_ops;
 }
 #endif
 
-#if	defined(ZFS_UBSAN_ENABLED)
-#if	defined(__has_attribute)
-#if	__has_attribute(no_sanitize_undefined)
-#define	ZFS_NO_SANITIZE_UNDEFINED __attribute__((no_sanitize_undefined))
-#elif	__has_attribute(no_sanitize)
-#define	ZFS_NO_SANITIZE_UNDEFINED __attribute__((no_sanitize("undefined")))
-#else
-#error	"Compiler has to support attribute "
-	"`no_sanitize_undefined` or `no_sanitize(\"undefined\")`"
-	"when compiling with UBSan enabled"
-#endif	/* __has_attribute(no_sanitize_undefined) */
-#endif	/* defined(__has_attribute) */
-#else
-#define	ZFS_NO_SANITIZE_UNDEFINED
-#endif	/* defined(ZFS_UBSAN_ENABLED) */
-
 #endif	/* _ZFS_FLETCHER_H */
diff --git a/module/zcommon/zfs_fletcher.c b/module/zcommon/zfs_fletcher.c
index eae854f3d..1d9b1cffc 100644
--- a/module/zcommon/zfs_fletcher.c
+++ b/module/zcommon/zfs_fletcher.c
@@ -301,21 +301,18 @@ fletcher_2_byteswap(const void *buf, uint64_t size,
 	(void) fletcher_2_incremental_byteswap((void *) buf, size, zcp);
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_scalar_init(fletcher_4_ctx_t *ctx)
 {
 	ZIO_SET_CHECKSUM(&ctx->scalar, 0, 0, 0, 0);
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_scalar_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp)
 {
 	memcpy(zcp, &ctx->scalar, sizeof (zio_cksum_t));
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_scalar_native(fletcher_4_ctx_t *ctx, const void *buf,
     uint64_t size)
@@ -339,7 +336,6 @@ fletcher_4_scalar_native(fletcher_4_ctx_t *ctx, const void *buf,
 	ZIO_SET_CHECKSUM(&ctx->scalar, a, b, c, d);
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_scalar_byteswap(fletcher_4_ctx_t *ctx, const void *buf,
     uint64_t size)
diff --git a/module/zcommon/zfs_fletcher_aarch64_neon.c b/module/zcommon/zfs_fletcher_aarch64_neon.c
index cd5fe545a..26f2115c4 100644
--- a/module/zcommon/zfs_fletcher_aarch64_neon.c
+++ b/module/zcommon/zfs_fletcher_aarch64_neon.c
@@ -48,14 +48,12 @@
 #include <sys/string.h>
 #include <zfs_fletcher.h>
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_aarch64_neon_init(fletcher_4_ctx_t *ctx)
 {
 	memset(ctx->aarch64_neon, 0, 4 * sizeof (zfs_fletcher_aarch64_neon_t));
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_aarch64_neon_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp)
 {
diff --git a/module/zcommon/zfs_fletcher_avx512.c b/module/zcommon/zfs_fletcher_avx512.c
index 81182ead2..95fc2b151 100644
--- a/module/zcommon/zfs_fletcher_avx512.c
+++ b/module/zcommon/zfs_fletcher_avx512.c
@@ -35,14 +35,12 @@
 #define	__asm __asm__ __volatile__
 #endif
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_avx512f_init(fletcher_4_ctx_t *ctx)
 {
 	memset(ctx->avx512, 0, 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)
 {
diff --git a/module/zcommon/zfs_fletcher_intel.c b/module/zcommon/zfs_fletcher_intel.c
index 6108bda7a..34590a155 100644
--- a/module/zcommon/zfs_fletcher_intel.c
+++ b/module/zcommon/zfs_fletcher_intel.c
@@ -47,14 +47,12 @@
 #include <sys/simd.h>
 #include <zfs_fletcher.h>
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_avx2_init(fletcher_4_ctx_t *ctx)
 {
 	memset(ctx->avx, 0, 4 * sizeof (zfs_fletcher_avx_t));
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_avx2_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp)
 {
diff --git a/module/zcommon/zfs_fletcher_sse.c b/module/zcommon/zfs_fletcher_sse.c
index 096472c9a..8ab9b9acb 100644
--- a/module/zcommon/zfs_fletcher_sse.c
+++ b/module/zcommon/zfs_fletcher_sse.c
@@ -49,14 +49,12 @@
 #include <sys/byteorder.h>
 #include <zfs_fletcher.h>
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_sse2_init(fletcher_4_ctx_t *ctx)
 {
 	memset(ctx->sse, 0, 4 * sizeof (zfs_fletcher_sse_t));
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_sse2_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp)
 {
diff --git a/module/zcommon/zfs_fletcher_superscalar.c b/module/zcommon/zfs_fletcher_superscalar.c
index 8b5b72a7b..2a80816ff 100644
--- a/module/zcommon/zfs_fletcher_superscalar.c
+++ b/module/zcommon/zfs_fletcher_superscalar.c
@@ -47,14 +47,12 @@
 #include <sys/string.h>
 #include <zfs_fletcher.h>
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_superscalar_init(fletcher_4_ctx_t *ctx)
 {
 	memset(ctx->superscalar, 0, 4 * sizeof (zfs_fletcher_superscalar_t));
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_superscalar_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp)
 {
@@ -70,7 +68,6 @@ fletcher_4_superscalar_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp)
 	ZIO_SET_CHECKSUM(zcp, A, B, C, D);
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_superscalar_native(fletcher_4_ctx_t *ctx,
     const void *buf, uint64_t size)
@@ -110,7 +107,6 @@ fletcher_4_superscalar_native(fletcher_4_ctx_t *ctx,
 	ctx->superscalar[3].v[1] = d2;
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_superscalar_byteswap(fletcher_4_ctx_t *ctx,
     const void *buf, uint64_t size)
diff --git a/module/zcommon/zfs_fletcher_superscalar4.c b/module/zcommon/zfs_fletcher_superscalar4.c
index bef387933..0b52bb63d 100644
--- a/module/zcommon/zfs_fletcher_superscalar4.c
+++ b/module/zcommon/zfs_fletcher_superscalar4.c
@@ -47,14 +47,12 @@
 #include <sys/string.h>
 #include <zfs_fletcher.h>
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_superscalar4_init(fletcher_4_ctx_t *ctx)
 {
 	memset(ctx->superscalar, 0, 4 * sizeof (zfs_fletcher_superscalar_t));
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_superscalar4_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp)
 {
@@ -84,7 +82,6 @@ fletcher_4_superscalar4_fini(fletcher_4_ctx_t *ctx, zio_cksum_t *zcp)
 	ZIO_SET_CHECKSUM(zcp, A, B, C, D);
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_superscalar4_native(fletcher_4_ctx_t *ctx,
     const void *buf, uint64_t size)
@@ -150,7 +147,6 @@ fletcher_4_superscalar4_native(fletcher_4_ctx_t *ctx,
 	ctx->superscalar[3].v[3] = d4;
 }
 
-ZFS_NO_SANITIZE_UNDEFINED
 static void
 fletcher_4_superscalar4_byteswap(fletcher_4_ctx_t *ctx,
     const void *buf, uint64_t size)