From patchwork Thu Feb 3 15:08:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Duoming Zhou X-Patchwork-Id: 12734267 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E6FFC433F5 for ; Thu, 3 Feb 2022 15:09:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351658AbiBCPJW (ORCPT ); Thu, 3 Feb 2022 10:09:22 -0500 Received: from mail.zju.edu.cn ([61.164.42.155]:24924 "EHLO zju.edu.cn" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S235565AbiBCPJV (ORCPT ); Thu, 3 Feb 2022 10:09:21 -0500 Received: from ubuntu.localdomain (unknown [10.15.192.164]) by mail-app4 (Coremail) with SMTP id cS_KCgCnHSkN8PthWcOkCA--.54810S2; Thu, 03 Feb 2022 23:09:05 +0800 (CST) From: Duoming Zhou To: linux-hams@vger.kernel.org Cc: dan.carpenter@oracle.com, thomas@osteried.de, jreuter@yaina.de, ralf@linux-mips.org, davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Duoming Zhou Subject: [PATCH] ax25: fix reference count leaks of ax25_dev Date: Thu, 3 Feb 2022 23:08:11 +0800 Message-Id: <20220203150811.42256-1-duoming@zju.edu.cn> X-Mailer: git-send-email 2.17.1 X-CM-TRANSID: cS_KCgCnHSkN8PthWcOkCA--.54810S2 X-Coremail-Antispam: 1UD129KBjvJXoW3JFy5Jr1DKFW5ZFW8uw4fuFg_yoWxtr18pF W0kayrArWktF47Ar4rGw4xWF15AryIv39rXryUuF1Ikw1rX3s8JF18tryUKry3GrWfAr18 X34DXr45Ar48AF7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvm1xkIjI8I6I8E6xAIw20EY4v20xvaj40_Wr0E3s1l1IIY67AE w4v_Jr0_Jr4l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2 IY67AKxVW5JVW7JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVWxJVW8Jr1l84ACjcxK6I8E 87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_GcCE3s1le2I262IYc4CY6c 8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_ Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwI xGrwACjI8F5VA0II8E6IAqYI8I648v4I1lFIxGxcIEc7CjxVA2Y2ka0xkIwI1l42xK82IY c2Ij64vIr41l42xK82IY6x8ErcxFaVAv8VW8uw4UJr1UMxC20s026xCaFVCjc4AY6r1j6r 4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF 67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2I x0cI8IcVCY1x0267AKxVWUJVW8JwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2 z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnU UI43ZEXa7VUbXdbUUUUUU== X-CM-SenderInfo: qssqjiasttq6lmxovvfxof0/ Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org The previous commit d01ffb9eee4a ("ax25: add refcount in ax25_dev to avoid UAF bugs") introduces refcount into ax25_dev, but there are reference leak paths in ax25_ctl_ioctl(), ax25_fwd_ioctl(), ax25_rt_add(), ax25_rt_del() and ax25_rt_opt(). This patch uses ax25_dev_put() and adjusts the position of ax25_addr_ax25dev() to fix reference cout leaks of ax25_dev. Fixes: d01ffb9eee4a ("ax25: add refcount in ax25_dev to avoid UAF bugs") Signed-off-by: Duoming Zhou Reviewed-by: Dan Carpenter --- include/net/ax25.h | 8 +++++--- net/ax25/af_ax25.c | 12 ++++++++---- net/ax25/ax25_dev.c | 24 +++++++++++++++++------- net/ax25/ax25_route.c | 16 +++++++++++----- 4 files changed, 41 insertions(+), 19 deletions(-) diff --git a/include/net/ax25.h b/include/net/ax25.h index 50b417df622..8221af1811d 100644 --- a/include/net/ax25.h +++ b/include/net/ax25.h @@ -294,10 +294,12 @@ static __inline__ void ax25_cb_put(ax25_cb *ax25) } } -#define ax25_dev_hold(__ax25_dev) \ - refcount_inc(&((__ax25_dev)->refcount)) +static inline void ax25_dev_hold(ax25_dev *ax25_dev) +{ + refcount_inc(&ax25_dev->refcount); +} -static __inline__ void ax25_dev_put(ax25_dev *ax25_dev) +static inline void ax25_dev_put(ax25_dev *ax25_dev) { if (refcount_dec_and_test(&ax25_dev->refcount)) { kfree(ax25_dev); diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c index 32f61978ff2..3e49d28824e 100644 --- a/net/ax25/af_ax25.c +++ b/net/ax25/af_ax25.c @@ -359,21 +359,25 @@ static int ax25_ctl_ioctl(const unsigned int cmd, void __user *arg) if (copy_from_user(&ax25_ctl, arg, sizeof(ax25_ctl))) return -EFAULT; - if ((ax25_dev = ax25_addr_ax25dev(&ax25_ctl.port_addr)) == NULL) - return -ENODEV; - if (ax25_ctl.digi_count > AX25_MAX_DIGIS) return -EINVAL; if (ax25_ctl.arg > ULONG_MAX / HZ && ax25_ctl.cmd != AX25_KILL) return -EINVAL; + ax25_dev = ax25_addr_ax25dev(&ax25_ctl.port_addr); + if (!ax25_dev) + return -ENODEV; + digi.ndigi = ax25_ctl.digi_count; for (k = 0; k < digi.ndigi; k++) digi.calls[k] = ax25_ctl.digi_addr[k]; - if ((ax25 = ax25_find_cb(&ax25_ctl.source_addr, &ax25_ctl.dest_addr, &digi, ax25_dev->dev)) == NULL) + ax25 = ax25_find_cb(&ax25_ctl.source_addr, &ax25_ctl.dest_addr, &digi, ax25_dev->dev); + if (!ax25) { + ax25_dev_put(ax25_dev); return -ENOTCONN; + } switch (ax25_ctl.cmd) { case AX25_KILL: diff --git a/net/ax25/ax25_dev.c b/net/ax25/ax25_dev.c index 770b787fb7b..d2a244e1c26 100644 --- a/net/ax25/ax25_dev.c +++ b/net/ax25/ax25_dev.c @@ -85,8 +85,8 @@ void ax25_dev_device_up(struct net_device *dev) spin_lock_bh(&ax25_dev_lock); ax25_dev->next = ax25_dev_list; ax25_dev_list = ax25_dev; - ax25_dev_hold(ax25_dev); spin_unlock_bh(&ax25_dev_lock); + ax25_dev_hold(ax25_dev); ax25_register_dev_sysctl(ax25_dev); } @@ -115,8 +115,8 @@ void ax25_dev_device_down(struct net_device *dev) if ((s = ax25_dev_list) == ax25_dev) { ax25_dev_list = s->next; - ax25_dev_put(ax25_dev); spin_unlock_bh(&ax25_dev_lock); + ax25_dev_put(ax25_dev); dev->ax25_ptr = NULL; dev_put_track(dev, &ax25_dev->dev_tracker); ax25_dev_put(ax25_dev); @@ -126,8 +126,8 @@ void ax25_dev_device_down(struct net_device *dev) while (s != NULL && s->next != NULL) { if (s->next == ax25_dev) { s->next = ax25_dev->next; - ax25_dev_put(ax25_dev); spin_unlock_bh(&ax25_dev_lock); + ax25_dev_put(ax25_dev); dev->ax25_ptr = NULL; dev_put_track(dev, &ax25_dev->dev_tracker); ax25_dev_put(ax25_dev); @@ -150,25 +150,35 @@ int ax25_fwd_ioctl(unsigned int cmd, struct ax25_fwd_struct *fwd) switch (cmd) { case SIOCAX25ADDFWD: - if ((fwd_dev = ax25_addr_ax25dev(&fwd->port_to)) == NULL) + fwd_dev = ax25_addr_ax25dev(&fwd->port_to); + if (!fwd_dev) { + ax25_dev_put(ax25_dev); return -EINVAL; - if (ax25_dev->forward != NULL) + } + if (ax25_dev->forward) { + ax25_dev_put(fwd_dev); + ax25_dev_put(ax25_dev); return -EINVAL; + } ax25_dev->forward = fwd_dev->dev; ax25_dev_put(fwd_dev); + ax25_dev_put(ax25_dev); break; case SIOCAX25DELFWD: - if (ax25_dev->forward == NULL) + if (!ax25_dev->forward) { + ax25_dev_put(ax25_dev); return -EINVAL; + } ax25_dev->forward = NULL; + ax25_dev_put(ax25_dev); break; default: + ax25_dev_put(ax25_dev); return -EINVAL; } - ax25_dev_put(ax25_dev); return 0; } diff --git a/net/ax25/ax25_route.c b/net/ax25/ax25_route.c index 1e32693833e..9751207f775 100644 --- a/net/ax25/ax25_route.c +++ b/net/ax25/ax25_route.c @@ -75,11 +75,13 @@ static int __must_check ax25_rt_add(struct ax25_routes_struct *route) ax25_dev *ax25_dev; int i; - if ((ax25_dev = ax25_addr_ax25dev(&route->port_addr)) == NULL) - return -EINVAL; if (route->digi_count > AX25_MAX_DIGIS) return -EINVAL; + ax25_dev = ax25_addr_ax25dev(&route->port_addr); + if (!ax25_dev) + return -EINVAL; + write_lock_bh(&ax25_route_lock); ax25_rt = ax25_route_list; @@ -91,6 +93,7 @@ static int __must_check ax25_rt_add(struct ax25_routes_struct *route) if (route->digi_count != 0) { if ((ax25_rt->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL) { write_unlock_bh(&ax25_route_lock); + ax25_dev_put(ax25_dev); return -ENOMEM; } ax25_rt->digipeat->lastrepeat = -1; @@ -101,6 +104,7 @@ static int __must_check ax25_rt_add(struct ax25_routes_struct *route) } } write_unlock_bh(&ax25_route_lock); + ax25_dev_put(ax25_dev); return 0; } ax25_rt = ax25_rt->next; @@ -108,6 +112,7 @@ static int __must_check ax25_rt_add(struct ax25_routes_struct *route) if ((ax25_rt = kmalloc(sizeof(ax25_route), GFP_ATOMIC)) == NULL) { write_unlock_bh(&ax25_route_lock); + ax25_dev_put(ax25_dev); return -ENOMEM; } @@ -116,11 +121,11 @@ static int __must_check ax25_rt_add(struct ax25_routes_struct *route) ax25_rt->dev = ax25_dev->dev; ax25_rt->digipeat = NULL; ax25_rt->ip_mode = ' '; - ax25_dev_put(ax25_dev); if (route->digi_count != 0) { if ((ax25_rt->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL) { write_unlock_bh(&ax25_route_lock); kfree(ax25_rt); + ax25_dev_put(ax25_dev); return -ENOMEM; } ax25_rt->digipeat->lastrepeat = -1; @@ -133,6 +138,7 @@ static int __must_check ax25_rt_add(struct ax25_routes_struct *route) ax25_rt->next = ax25_route_list; ax25_route_list = ax25_rt; write_unlock_bh(&ax25_route_lock); + ax25_dev_put(ax25_dev); return 0; } @@ -173,8 +179,8 @@ static int ax25_rt_del(struct ax25_routes_struct *route) } } } - ax25_dev_put(ax25_dev); write_unlock_bh(&ax25_route_lock); + ax25_dev_put(ax25_dev); return 0; } @@ -216,8 +222,8 @@ static int ax25_rt_opt(struct ax25_route_opt_struct *rt_option) } out: - ax25_dev_put(ax25_dev); write_unlock_bh(&ax25_route_lock); + ax25_dev_put(ax25_dev); return err; }