From: Kevin Wolf <kwolf@redhat.com>
Date: Tue, 20 May 2014 11:26:40 +0000 (+0200)
Subject: curl: Handle failure for potentially large allocations
X-Git-Tag: qemu-xen-4.6.0-rc1~264^2~19
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=8dc7a7725bd6db2aa7e3c09b49bc21a1a25f40cb;p=qemu-xen.git

curl: Handle failure for potentially large allocations

Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.

This patch addresses the allocations in the curl block driver.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
---

diff --git a/block/curl.c b/block/curl.c
index 79ff2f1e41..d4b85d20a5 100644
--- a/block/curl.c
+++ b/block/curl.c
@@ -640,7 +640,13 @@ static void curl_readv_bh_cb(void *p)
     state->buf_start = start;
     state->buf_len = acb->end + s->readahead_size;
     end = MIN(start + state->buf_len, s->len) - 1;
-    state->orig_buf = g_malloc(state->buf_len);
+    state->orig_buf = g_try_malloc(state->buf_len);
+    if (state->buf_len && state->orig_buf == NULL) {
+        curl_clean_state(state);
+        acb->common.cb(acb->common.opaque, -ENOMEM);
+        qemu_aio_release(acb);
+        return;
+    }
     state->acb[0] = acb;
 
     snprintf(state->range, 127, "%zd-%zd", start, end);