Improve failure loggin when reading kernel config

aya-rs · Sep 27, 2024 · d1e8243 · d1e8243
1 parent 005fb60
commit d1e8243
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Showing 2 changed files with 49 additions and 32 deletions.
diff --git a/aya-obj/src/btf/btf.rs b/aya-obj/src/btf/btf.rs
@@ -544,7 +544,9 @@ impl Btf {
         target_var_name: &str,
     ) -> Result<(String, Var), BtfError> {
         for t in &self.types.types {
-            let BtfType::DataSec(d) = t else { continue; };
+            let BtfType::DataSec(d) = t else {
+                continue;
+            };
             let sec_name = self.string_at(d.name_offset)?;
 
             for d in &d.entries {

diff --git a/aya/src/bpf.rs b/aya/src/bpf.rs
@@ -159,37 +159,8 @@ fn compute_kconfig_definition(features: &Features) -> HashMap<String, Vec<u8>> {
         to_bytes(bpf_syscall_wrapper).to_vec(),
     );
 
-    let mut raw_config_opt = None;
-
-    let proc_config_path = PathBuf::from("/proc/config.gz");
-
-    if proc_config_path.exists() {
-        if let Ok(file) = File::open(proc_config_path) {
-            let mut file = GzDecoder::new(file);
-            let mut output = String::new();
-            if file.read_to_string(&mut output).is_ok() {
-                raw_config_opt = Some(output);
-            }
-        }
-    }
-
-    if raw_config_opt.is_none() {
-        if let Ok(release) = sys::kernel_release() {
-            let config_path = PathBuf::from("/boot").join(format!("config-{}", release));
-
-            if config_path.exists() {
-                if let Ok(mut file) = File::open(config_path) {
-                    let mut output = String::new();
-                    if file.read_to_string(&mut output).is_ok() {
-                        raw_config_opt = Some(output);
-                    }
-                }
-            }
-        }
-    }
-
-    if let Some(raw_config) = raw_config_opt {
-        for line in raw_config.split('\n') {
+    if let Some(raw_config) = read_kconfig() {
+        for line in raw_config.lines() {
             if !line.starts_with("CONFIG_") {
                 continue;
             }
@@ -230,6 +201,50 @@ fn compute_kconfig_definition(features: &Features) -> HashMap<String, Vec<u8>> {
     result
 }
 
+fn read_kconfig() -> Option<String> {
+    let config_path = PathBuf::from("/proc/config.gz");
+    if config_path.exists() {
+        debug!("Found kernel config at {}", config_path.to_string_lossy());
+        return read_kconfig_file(&config_path, true);
+    }
+
+    let Ok(release) = sys::kernel_release() else {
+        return None;
+    };
+
+    let config_path = PathBuf::from("/boot").join(format!("config-{}", release));
+    if config_path.exists() {
+        debug!("Found kernel config at {}", config_path.to_string_lossy());
+        return read_kconfig_file(&config_path, false);
+    }
+
+    None
+}
+
+fn read_kconfig_file(path: &PathBuf, gzip: bool) -> Option<String> {
+    let mut output = String::new();
+
+    let res = if gzip {
+        File::open(path)
+            .map(GzDecoder::new)
+            .and_then(|mut file| file.read_to_string(&mut output))
+    } else {
+        File::open(path).and_then(|mut file| file.read_to_string(&mut output))
+    };
+
+    match res {
+        Ok(_) => Some(output),
+        Err(e) => {
+            warn!(
+                "Unable to read kernel config {}: {:?}",
+                path.to_string_lossy(),
+                e
+            );
+            None
+        }
+    }
+}
+
 /// Builder style API for advanced loading of eBPF programs.
 ///
 /// Loading eBPF code involves a few steps, including loading maps and applying