diff --git a/mercurial/exchange.py b/mercurial/exchange.py
--- a/mercurial/exchange.py
+++ b/mercurial/exchange.py
@@ -738,16 +738,20 @@ def unbundle(repo, cg, heads, source, ur
         check_heads(repo, heads, 'uploading changes')
         # push can proceed
         if util.safehasattr(cg, 'params'):
-            tr = repo.transaction('unbundle')
-            tr.hookargs['bundle2-exp'] = '1'
-            r = bundle2.processbundle(repo, cg, lambda: tr).reply
-            cl = repo.unfiltered().changelog
-            p = cl.writepending() and repo.root or ""
-            repo.hook('b2x-pretransactionclose', throw=True, source=source,
-                      url=url, pending=p, **tr.hookargs)
-            tr.close()
-            repo.hook('b2x-transactionclose', source=source, url=url,
-                      **tr.hookargs)
+            try:
+                tr = repo.transaction('unbundle')
+                tr.hookargs['bundle2-exp'] = '1'
+                r = bundle2.processbundle(repo, cg, lambda: tr).reply
+                cl = repo.unfiltered().changelog
+                p = cl.writepending() and repo.root or ""
+                repo.hook('b2x-pretransactionclose', throw=True, source=source,
+                          url=url, pending=p, **tr.hookargs)
+                tr.close()
+                repo.hook('b2x-transactionclose', source=source, url=url,
+                          **tr.hookargs)
+            except Exception, exc:
+                exc.duringunbundle2 = True
+                raise
         else:
             r = changegroup.addchangegroup(repo, cg, source, url)
     finally:
diff --git a/tests/test-bundle2.t b/tests/test-bundle2.t
--- a/tests/test-bundle2.t
+++ b/tests/test-bundle2.t
@@ -1043,3 +1043,40 @@ Doing the actual push: race
   abort: push failed:
   'repository changed while pushing - please try again'
   [255]
+
+Doing the actual push: hook abort
+
+  $ cat << EOF >> $HGRCPATH
+  > [failpush]
+  > reason =
+  > [hooks]
+  > b2x-pretransactionclose.failpush = false
+  > EOF
+
+  $ "$TESTDIR/killdaemons.py" $DAEMON_PIDS
+  $ hg -R other serve -p $HGPORT2 -d --pid-file=other.pid -E other-error.log
+  $ cat other.pid >> $DAEMON_PIDS
+
+  $ hg -R main push other -r e7ec4e813ba6
+  pushing to other
+  searching for changes
+  transaction abort!
+  rollback completed
+  abort: b2x-pretransactionclose.failpush hook exited with status 1
+  [255]
+
+  $ hg -R main push ssh://user@dummy/other -r e7ec4e813ba6
+  pushing to ssh://user@dummy/other
+  searching for changes
+  abort: b2x-pretransactionclose.failpush hook exited with status 1
+  remote: transaction abort!
+  remote: rollback completed
+  [255]
+
+  $ hg -R main push http://localhost:$HGPORT2/ -r e7ec4e813ba6
+  pushing to http://localhost:$HGPORT2/
+  searching for changes
+  abort: b2x-pretransactionclose.failpush hook exited with status 1
+  [255]
+
+