Commit acbbc036 authored by Amit Shah's avatar Amit Shah Committed by Anthony Liguori
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rng random backend: check for -EAGAIN errors on read 



Not handling EAGAIN triggers the assert

qemu/backends/rng-random.c:44:entropy_available: assertion failed: (len != -1)
Aborted (core dumped)

This happens when starting a guest with '-device virtio-rng-pci',
issuing a 'cat /dev/hwrng' in the guest, while also doing 'cat
/dev/random' on the host.

Reported-by: default avataryunpingzheng <yunzheng@redhat.com>
Signed-off-by: default avatarAmit Shah <amit.shah@redhat.com>
Message-id: eacda84dfaf2d99cf6d250b678be4e4d6c2088fb.1366108096.git.amit.shah@redhat.com
Signed-off-by: default avatarAnthony Liguori <aliguori@us.ibm.com>
parent 7dda5dc8

backends/rng-random.c

+3 −0
Original line number Diff line number Diff line
@@ -41,6 +41,9 @@ static void entropy_available(void *opaque) 
    ssize_t len;



    len = read(s->fd, buffer, s->size);

    if (len < 0 && errno == EAGAIN) {

        return;

    }

    g_assert(len != -1);



    s->receive_func(s->opaque, buffer, len);