Re: [Qemu-devel] [RFC PATCH] char-socket: hold chr_write_lock during tcp_chr_free_connection()

[Daniel P . Berrangé]

On Wed, Feb 06, 2019 at 01:52:59PM +0100, Paolo Bonzini wrote:
> On 06/02/19 13:49, Daniel P. Berrangé wrote:
> > On Wed, Feb 06, 2019 at 02:43:45PM +0200, Alberto Garcia wrote:
> >> There's a race condition in which the tcp_chr_read() ioc handler can
> >> close a connection that is being written to from another thread.
> > Isn't the chardev only ever supposed to be read/written from a
> > single thread.
> > 
> 
> No, writes from multiple threads are allowed; of course they have to
> have proper locking to avoid mixing messages.
> 
> Reads have to happen from a single thread because they are tied to the
> chr_read handlers.

Ok, then we really ought to have full locking around tcp_chr_disconnect

Regards,
Daniel
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