Re: [Qemu-devel] [PATCH v3 01/26] chardev: avoid crash if no associated address

[Daniel P . Berrangé]

On Mon, Jun 18, 2018 at 06:17:04PM +0200, Marc-André Lureau wrote:
> A socket chardev may not have associated address (when adding client
> fd manually for example). But on disconnect, updating socket filename
> expects an address and may lead to this crash:
> 
>   Thread 1 "qemu-system-x86" received signal SIGSEGV, Segmentation fault.
>   0x0000555555d8c70c in SocketAddress_to_str (prefix=0x555556043062 
> "disconnected:", addr=0x0, is_listen=false, is_telnet=false) at 
> /home/elmarco/src/qq/chardev/char-socket.c:388
>   388     switch (addr->type) {
>   (gdb) bt
>   #0  0x0000555555d8c70c in SocketAddress_to_str (prefix=0x555556043062 
> "disconnected:", addr=0x0, is_listen=false, is_telnet=false) at 
> /home/elmarco/src/qq/chardev/char-socket.c:388
>   #1  0x0000555555d8c8aa in update_disconnected_filename (s=0x555556b1ed00) 
> at /home/elmarco/src/qq/chardev/char-socket.c:419
>   #2  0x0000555555d8c959 in tcp_chr_disconnect (chr=0x555556b1ed00) at 
> /home/elmarco/src/qq/chardev/char-socket.c:438
>   #3  0x0000555555d8cba1 in tcp_chr_hup (channel=0x555556b75690, 
> cond=G_IO_HUP, opaque=0x555556b1ed00) at 
> /home/elmarco/src/qq/chardev/char-socket.c:482
>   #4  0x0000555555da596e in qio_channel_fd_source_dispatch 
> (source=0x555556bb68b0, callback=0x555555d8cb58 <tcp_chr_hup>, 
> user_data=0x555556b1ed00) at /home/elmarco/src/qq/io/channel-watch.c:84
> 
> Replace filename with a generic "disconnected:socket" in this case.
> 
> Signed-off-by: Marc-André Lureau <address@hidden>
> ---
>  chardev/char-socket.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)

Reviewed-by: Daniel P. Berrangé <address@hidden>



Regards,
Daniel
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