From 96fc598f76beac1deb0c9564dc67416f70ae4ac4 Mon Sep 17 00:00:00 2001
From: Ming-Hung Tsai <mtsai@redhat.com>
Date: Tue, 30 Jan 2024 15:20:31 +0800
Subject: [PATCH 5/6] [cache_check] Fix boundary check on the bitset for cached
 blocks

The bitset for cached block addresses grows dynamically if the metadata
is not shutdown properly, in which the size hint of the slow (backing)
device is not available. Fix a bug in determining whether resizing is
needed (bz2258485).

(cherry picked from commit d2390a50f38d88f0f32b13e59444bbbca7e660b3)
---
 src/cache/check.rs   |  6 +++---
 tests/cache_check.rs | 45 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+), 3 deletions(-)

diff --git a/src/cache/check.rs b/src/cache/check.rs
index 18bd51b3..c71d3059 100644
--- a/src/cache/check.rs
+++ b/src/cache/check.rs
@@ -19,7 +19,7 @@ use crate::report::*;
 
 //------------------------------------------
 
-// 16m entries is capable for a 1TB cache with 64KB block size
+// 16m entries is capable to address a 1TB device with 64KB block size
 const DEFAULT_OBLOCKS: usize = 16777216;
 
 fn inc_superblock(sm: &ASpaceMap) -> anyhow::Result<()> {
@@ -82,7 +82,7 @@ mod format1 {
             }
             let mut seen_oblocks = self.seen_oblocks.lock().unwrap();
 
-            if m.oblock as usize > seen_oblocks.len() {
+            if m.oblock as usize >= seen_oblocks.len() {
                 seen_oblocks.grow(m.oblock as usize + 1);
             } else if seen_oblocks.contains(m.oblock as usize) {
                 return Err(array::value_err("origin block already mapped".to_string()));
@@ -179,7 +179,7 @@ mod format2 {
                 ));
             }
 
-            if m.oblock as usize > seen_oblocks.len() {
+            if m.oblock as usize >= seen_oblocks.len() {
                 seen_oblocks.grow(m.oblock as usize + 1);
             } else if seen_oblocks.contains(m.oblock as usize) {
                 return Err(array::value_err("origin block already mapped".to_string()));
diff --git a/tests/cache_check.rs b/tests/cache_check.rs
index 81f4c578..8988694a 100644
--- a/tests/cache_check.rs
+++ b/tests/cache_check.rs
@@ -11,6 +11,8 @@ use common::program::*;
 use common::target::*;
 use common::test_dir::*;
 
+use std::io::Write;
+
 //------------------------------------------
 
 const USAGE: &str = "Validates cache metadata on a device or file.
@@ -294,3 +296,46 @@ fn no_clear_needs_check_if_error() -> Result<()> {
 }
 
 //------------------------------------------
+
+fn metadata_without_slow_dev_size_info(use_v1: bool) -> Result<()> {
+    let mut td = TestDir::new()?;
+
+    // The input metadata has a cached oblock with address equals to the default bitset size
+    // boundary (DEFAULT_OBLOCKS = 16777216), triggering bitset resize.
+    let xml = td.mk_path("meta.xml");
+    let mut file = std::fs::File::create(&xml)?;
+    file.write_all(b"<superblock uuid=\"\" block_size=\"128\" nr_cache_blocks=\"1024\" policy=\"smq\" hint_width=\"4\">
+  <mappings>
+    <mapping cache_block=\"0\" origin_block=\"16777216\" dirty=\"false\"/>
+  </mappings>
+  <hints>
+    <hint cache_block=\"0\" data=\"AAAAAA==\"/>
+  </hints>
+</superblock>")?;
+
+    let md = td.mk_path("meta.bin");
+    thinp::file_utils::create_sized_file(&md, 4096 * 4096)?;
+
+    let cache_restore_args = if use_v1 {
+        args!["-i", &xml, "-o", &md, "--metadata-version=1"]
+    } else {
+        args!["-i", &xml, "-o", &md, "--metadata-version=2"]
+    };
+
+    run_ok(cache_restore_cmd(cache_restore_args))?;
+    run_ok(cache_check_cmd(args![&md]))?;
+
+    Ok(())
+}
+
+#[test]
+fn metadata_v1_without_slow_dev_size_info() -> Result<()> {
+    metadata_without_slow_dev_size_info(true)
+}
+
+#[test]
+fn metadata_v2_without_slow_dev_size_info() -> Result<()> {
+    metadata_without_slow_dev_size_info(false)
+}
+
+//------------------------------------------
-- 
2.43.0