[pbs-devel] [PATCH proxmox-backup v2] tape: mam: actually enforcing the length when writing attributes

[Dominik Csapak]

we have to check against the length of the attribute, not the u16
maximum value. also improve the log output to tell the user what
the actual length was

Signed-off-by: Dominik Csapak <d.csapak at proxmox.com>
---
changes from v1:
* include the lengths in the error message
 pbs-tape/src/sg_tape/mam.rs | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/pbs-tape/src/sg_tape/mam.rs b/pbs-tape/src/sg_tape/mam.rs
index 4e995d0b..d8398e58 100644
--- a/pbs-tape/src/sg_tape/mam.rs
+++ b/pbs-tape/src/sg_tape/mam.rs
@@ -169,8 +169,12 @@ pub fn write_mam_attribute<F: AsRawFd>(
     attr_data.extend(data);
     if !data.is_empty() && data.len() < attribute.len as usize {
         attr_data.resize(attr_data.len() - data.len() + attribute.len as usize, 0);
-    } else if data.len() > u16::MAX as usize {
-        bail!("data to long");
+    } else if data.len() > attribute.len as usize {
+        bail!(
+            "attribute data length {} over the maximum allowed length {}",
+            data.len(),
+            attribute.len
+        );
     }
 
     parameters.extend(attr_data);
-- 
2.39.2