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[82.30.61.225]) by smtp.gmail.com with ESMTPSA id j9-20020a05600c190900b0039db31f6372sm26053230wmq.2.2022.07.19.06.51.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 Jul 2022 06:51:30 -0700 (PDT) Date: Tue, 19 Jul 2022 14:51:28 +0100 From: "Dr. David Alan Gilbert" To: Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= Cc: qemu-devel@nongnu.org, Juan Quintela Subject: Re: [PATCH] migration: remove unreachable code after reading data Message-ID: References: <20220627135318.156121-1-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20220627135318.156121-1-berrange@redhat.com> User-Agent: Mutt/2.2.6 (2022-06-05) Received-SPF: pass client-ip=170.10.129.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Daniel P. Berrangé (berrange@redhat.com) wrote: > The code calls qio_channel_read() in a loop when it reports > QIO_CHANNEL_ERR_BLOCK. This code is reported when errno==EAGAIN. > > As such the later block of code will always hit the 'errno != EAGAIN' > condition, making the final 'else' unreachable. > > Fixes: Coverity CID 1490203 > Signed-off-by: Daniel P. Berrangé Queued > --- > migration/qemu-file.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/migration/qemu-file.c b/migration/qemu-file.c > index 1e80d496b7..1615c48b7e 100644 > --- a/migration/qemu-file.c > +++ b/migration/qemu-file.c > @@ -384,10 +384,8 @@ static ssize_t qemu_fill_buffer(QEMUFile *f) > f->total_transferred += len; > } else if (len == 0) { > qemu_file_set_error_obj(f, -EIO, local_error); > - } else if (len != -EAGAIN) { > - qemu_file_set_error_obj(f, len, local_error); > } else { > - error_free(local_error); > + qemu_file_set_error_obj(f, len, local_error); > } > > return len; > -- > 2.36.1 > > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK