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envelope-from=pbonzini@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org If hostlen is zero, there is a possibility that addrstr[hostlen - 1] underflows and, if a closing bracked is there, hostlen - 2 is passed to g_strndup() on the next line. If websocket==false then addrstr[0] would be a colon, but if websocket==true this could in principle happen. Fix it by checking hostlen. Reported by Coverity. Signed-off-by: Paolo Bonzini --- ui/vnc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ui/vnc.c b/ui/vnc.c index bbd8b6baaeca..9d8a24dd8a69 100644 --- a/ui/vnc.c +++ b/ui/vnc.c @@ -3751,7 +3751,7 @@ static int vnc_display_get_address(const char *addrstr, addr->type = SOCKET_ADDRESS_TYPE_INET; inet = &addr->u.inet; - if (addrstr[0] == '[' && addrstr[hostlen - 1] == ']') { + if (hostlen && addrstr[0] == '[' && addrstr[hostlen - 1] == ']') { inet->host = g_strndup(addrstr + 1, hostlen - 2); } else { inet->host = g_strndup(addrstr, hostlen);