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Blame 0005-curl-Don-t-deref-NULL-pointer-in-call-to-aio_poll.patch

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From 1ea3e3a38b5bdb144a7206654c51f8f4768077f3 Mon Sep 17 00:00:00 2001
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From: "Richard W.M. Jones" <rjones@redhat.com>
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Date: Thu, 28 Aug 2014 09:04:21 +0100
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Subject: [PATCH] curl: Don't deref NULL pointer in call to aio_poll.
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MIME-Version: 1.0
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Content-Type: text/plain; charset=UTF-8
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Content-Transfer-Encoding: 8bit
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In commit 63f0f45f2e89b60ff8245fec81328ddfde42a303 the following
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mechanical change was made:
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         if (!state) {
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-            qemu_aio_wait();
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+            aio_poll(state->s->aio_context, true);
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         }
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The new code now checks if state is NULL and then dereferences it
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('state->s') which is obviously incorrect.
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This commit replaces state->s->aio_context with
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bdrv_get_aio_context(bs), fixing this problem.  The two other hunks
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are concerned with getting the BlockDriverState pointer bs to where it
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is needed.
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The original bug causes a segfault when using libguestfs to access a
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VMware vCenter Server and doing any kind of complex read-heavy
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operations.  With this commit the segfault goes away.
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Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
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Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
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Reviewed-by: BenoƮt Canet <benoit.canet@nodalink.com>
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Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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(cherry picked from commit a2f468e48f8b6559ec9123e94948bc373b788941)
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---
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 block/curl.c | 8 ++++----
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 1 file changed, 4 insertions(+), 4 deletions(-)
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diff --git a/block/curl.c b/block/curl.c
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index 537e257..d28b701 100644
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--- a/block/curl.c
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+++ b/block/curl.c
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@@ -357,7 +357,7 @@ static void curl_multi_timeout_do(void *arg)
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 #endif
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 }
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-static CURLState *curl_init_state(BDRVCURLState *s)
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+static CURLState *curl_init_state(BlockDriverState *bs, BDRVCURLState *s)
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 {
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     CURLState *state = NULL;
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     int i, j;
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@@ -375,7 +375,7 @@ static CURLState *curl_init_state(BDRVCURLState *s)
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             break;
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         }
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         if (!state) {
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-            aio_poll(state->s->aio_context, true);
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+            aio_poll(bdrv_get_aio_context(bs), true);
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         }
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     } while(!state);
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@@ -566,7 +566,7 @@ static int curl_open(BlockDriverState *bs, QDict *options, int flags,
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     DPRINTF("CURL: Opening %s\n", file);
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     s->aio_context = bdrv_get_aio_context(bs);
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     s->url = g_strdup(file);
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-    state = curl_init_state(s);
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+    state = curl_init_state(bs, s);
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     if (!state)
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         goto out_noclean;
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@@ -651,7 +651,7 @@ static void curl_readv_bh_cb(void *p)
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     }
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     // No cache found, so let's start a new request
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-    state = curl_init_state(s);
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+    state = curl_init_state(acb->common.bs, s);
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     if (!state) {
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         acb->common.cb(acb->common.opaque, -EIO);
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         qemu_aio_release(acb);