From owner-freebsd-wireless@FreeBSD.ORG Sat Apr 25 01:04:06 2015 Return-Path: Delivered-To: freebsd-wireless@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 6E977D6F for ; Sat, 25 Apr 2015 01:04:06 +0000 (UTC) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 3DC1E1A70 for ; Sat, 25 Apr 2015 01:04:06 +0000 (UTC) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.14.9/8.14.9) with ESMTP id t3P146OA025666 for ; Sat, 25 Apr 2015 01:04:06 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-wireless@FreeBSD.org Subject: [Bug 199676] [net80211] [patch]: fix possible kernel panic in IBSS mode (iv_bss may be freed twice) Date: Sat, 25 Apr 2015 01:04:06 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: wireless X-Bugzilla-Version: 11.0-CURRENT X-Bugzilla-Keywords: patch X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: s3erios@gmail.com X-Bugzilla-Status: New X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-wireless@FreeBSD.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status keywords bug_severity priority component assigned_to reporter attachments.created Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-wireless@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: "Discussions of 802.11 stack, tools device driver development." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 25 Apr 2015 01:04:06 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=199676 Bug ID: 199676 Summary: [net80211] [patch]: fix possible kernel panic in IBSS mode (iv_bss may be freed twice) Product: Base System Version: 11.0-CURRENT Hardware: Any OS: Any Status: New Keywords: patch Severity: Affects Only Me Priority: --- Component: wireless Assignee: freebsd-wireless@FreeBSD.org Reporter: s3erios@gmail.com Keywords: patch Created attachment 155958 --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=155958&action=edit Remove old iv_bss entry from the node table This may happen on RUN -> SCAN -> RUN -> SCAN state transition: 1. RUN -> SCAN: in ieee80211_sta_join1(): iv_bss will be moved to obss, refcnt will be reduced by 2 (default minimum). Now, if old iv_bss have some extra references (for example, from unacknowledged probe responses), it will not be freed and will stay in the node table. 2. SCAN -> RUN. 3. If old iv_bss will not be deleted by the time when the next RUN -> SCAN state transition occurs, then sta_leave() will reduce it's reference counter once more. As a result, two last users will free it -> this will lead to kernel panic. In this patch old iv_bss entry is explicitly removed from the node table in ieee80211_sta_join1() (as a result, it will not be processed by sta_leave()). -- You are receiving this mail because: You are the assignee for the bug.