From: Adam Kupczyk <akupczyk@ibm.com>
Date: Wed, 18 Jun 2025 10:25:21 +0000 (+0000)
Subject: bluestore: Fix _setattr() with rare memory alignments
X-Git-Url: http://git.apps.os.sepia.ceph.com/?a=commitdiff_plain;h=ffb256f9374c7189cf0c0692f9ef6f562d6a2155;p=ceph.git

bluestore: Fix _setattr() with rare memory alignments

Fix case bufferlist is length 0.

Signed-off-by: Adam Kupczyk <akupczyk@ibm.com>
(cherry picked from commit e82bf6d0fd8bf4e461441a7e0cab87397043c754)
---

diff --git a/src/os/bluestore/BlueStore.cc b/src/os/bluestore/BlueStore.cc
index d76442e9a57c0..6ccf1201df216 100644
--- a/src/os/bluestore/BlueStore.cc
+++ b/src/os/bluestore/BlueStore.cc
@@ -18004,11 +18004,15 @@ int BlueStore::_setattr(TransContext *txc,
 	   << " " << name << " (" << val.length() << " bytes)"
 	   << dendl;
   int r = 0;
-
-  if (!val.is_contiguous() || val.front().is_partial()) {
-    val.rebuild();
+  auto& b = o->onode.attrs[name.c_str()];
+  if (val.length() == 0) {
+    b = bufferptr("", 0);
+  } else {
+    if (!val.is_contiguous() || val.front().is_partial()) {
+      val.rebuild();
+    }
+    b = val.front();
   }
-  auto& b = o->onode.attrs[name.c_str()] = val.front();
   b.reassign_to_mempool(mempool::mempool_bluestore_cache_meta);
 
   txc->write_onode(o);