From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A59DB2DC32D; Tue, 2 Sep 2025 13:35:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756820129; cv=none; b=ALOhUlPXF6noNPLU66p4hXg6XVc/BtUNmmW8jvAEn2WjGDe7dVWKLq4/fTjKUZ5bdJEKADaa9j9CoLgGPz9jQW3/raXLuF1y9JQWLzDA+6FGbbW+BwXL3xPs2tyWot91cZhyFIhhJPMctBPeBDBzMHWu7yvGSIL+l2AtHh49gEw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756820129; c=relaxed/simple; bh=oyRfPJ6bVOyHtXD7k05ONsEqj2wjoHm51MUzLidoNHU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Rlo/Q9hmatAPq9n4Ri1CkqvCsAX62hPCpXxnf6OQpCvhclx6GwaYyy/m9nwWdKkVOOsFx46vdyS0NZiEQEHgnkLpU7oxqHsb6eUmfBp72a0lMibjlKhQjMdVZU0Yig5s9zpaSa2cdlnuRkABAT0WTlCrvBQfuKwyg4fJahyGbDA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=OpT0NByd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="OpT0NByd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 283EBC4CEED; Tue, 2 Sep 2025 13:35:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1756820129; bh=oyRfPJ6bVOyHtXD7k05ONsEqj2wjoHm51MUzLidoNHU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OpT0NBydwKRUi9iE5lKkzspyHYyB1ztjJsV23zfUfcpVzIlUP/46LeRsc8PcwlotP EmHU05Axgf4IEx6DGPx4v2NV1yywcbLLqdIdT3/a9i0Pejz7mMFXMBW9q5MWuLe2By 44qWqvlZPNMTGfQhrjuHCZZLmih/+dvxXnosuTE0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+942297eecf7d2d61d1f1@syzkaller.appspotmail.com, Takamitsu Iwai , Kuniyuki Iwashima , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.12 61/95] net: rose: include node references in rose_neigh refcount Date: Tue, 2 Sep 2025 15:20:37 +0200 Message-ID: <20250902131941.946022064@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20250902131939.601201881@linuxfoundation.org> References: <20250902131939.601201881@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Takamitsu Iwai [ Upstream commit da9c9c877597170b929a6121a68dcd3dd9a80f45 ] Current implementation maintains two separate reference counting mechanisms: the 'count' field in struct rose_neigh tracks references from rose_node structures, while the 'use' field (now refcount_t) tracks references from rose_sock. This patch merges these two reference counting systems using 'use' field for proper reference management. Specifically, this patch adds incrementing and decrementing of rose_neigh->use when rose_neigh->count is incremented or decremented. This patch also modifies rose_rt_free(), rose_rt_device_down() and rose_clear_route() to properly release references to rose_neigh objects before freeing a rose_node through rose_remove_node(). These changes ensure rose_neigh structures are properly freed only when all references, including those from rose_node structures, are released. As a result, this resolves a slab-use-after-free issue reported by Syzbot. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+942297eecf7d2d61d1f1@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=942297eecf7d2d61d1f1 Signed-off-by: Takamitsu Iwai Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250823085857.47674-4-takamitz@amazon.co.jp Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/rose/rose_route.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/net/rose/rose_route.c b/net/rose/rose_route.c index 42460da0854d5..6acbb795c506d 100644 --- a/net/rose/rose_route.c +++ b/net/rose/rose_route.c @@ -178,6 +178,7 @@ static int __must_check rose_add_node(struct rose_route_struct *rose_route, } } rose_neigh->count++; + rose_neigh_hold(rose_neigh); goto out; } @@ -187,6 +188,7 @@ static int __must_check rose_add_node(struct rose_route_struct *rose_route, rose_node->neighbour[rose_node->count] = rose_neigh; rose_node->count++; rose_neigh->count++; + rose_neigh_hold(rose_neigh); } out: @@ -322,6 +324,7 @@ static int rose_del_node(struct rose_route_struct *rose_route, for (i = 0; i < rose_node->count; i++) { if (rose_node->neighbour[i] == rose_neigh) { rose_neigh->count--; + rose_neigh_put(rose_neigh); if (rose_neigh->count == 0) { rose_remove_neigh(rose_neigh); @@ -430,6 +433,7 @@ int rose_add_loopback_node(const rose_address *address) rose_node_list = rose_node; rose_loopback_neigh->count++; + rose_neigh_hold(rose_loopback_neigh); out: spin_unlock_bh(&rose_node_list_lock); @@ -461,6 +465,7 @@ void rose_del_loopback_node(const rose_address *address) rose_remove_node(rose_node); rose_loopback_neigh->count--; + rose_neigh_put(rose_loopback_neigh); out: spin_unlock_bh(&rose_node_list_lock); @@ -500,6 +505,7 @@ void rose_rt_device_down(struct net_device *dev) memmove(&t->neighbour[i], &t->neighbour[i + 1], sizeof(t->neighbour[0]) * (t->count - i)); + rose_neigh_put(s); } if (t->count <= 0) @@ -543,6 +549,7 @@ static int rose_clear_routes(void) { struct rose_neigh *s, *rose_neigh; struct rose_node *t, *rose_node; + int i; spin_lock_bh(&rose_node_list_lock); spin_lock_bh(&rose_neigh_list_lock); @@ -553,8 +560,12 @@ static int rose_clear_routes(void) while (rose_node != NULL) { t = rose_node; rose_node = rose_node->next; - if (!t->loopback) + + if (!t->loopback) { + for (i = 0; i < rose_node->count; i++) + rose_neigh_put(t->neighbour[i]); rose_remove_node(t); + } } while (rose_neigh != NULL) { @@ -1189,7 +1200,7 @@ static int rose_neigh_show(struct seq_file *seq, void *v) (rose_neigh->loopback) ? "RSLOOP-0" : ax2asc(buf, &rose_neigh->callsign), rose_neigh->dev ? rose_neigh->dev->name : "???", rose_neigh->count, - refcount_read(&rose_neigh->use) - 1, + refcount_read(&rose_neigh->use) - rose_neigh->count - 1, (rose_neigh->dce_mode) ? "DCE" : "DTE", (rose_neigh->restarted) ? "yes" : "no", ax25_display_timer(&rose_neigh->t0timer) / HZ, @@ -1294,6 +1305,7 @@ void __exit rose_rt_free(void) struct rose_neigh *s, *rose_neigh = rose_neigh_list; struct rose_node *t, *rose_node = rose_node_list; struct rose_route *u, *rose_route = rose_route_list; + int i; while (rose_neigh != NULL) { s = rose_neigh; @@ -1307,6 +1319,8 @@ void __exit rose_rt_free(void) t = rose_node; rose_node = rose_node->next; + for (i = 0; i < t->count; i++) + rose_neigh_put(t->neighbour[i]); rose_remove_node(t); } -- 2.50.1