kernel/git/stable/linux.git/drivers/isdn/mISDN/layer2.c, branch master

net: remove ISDN subsystem and Bluetooth CMTP

2026-04-23T17:24:02+00:00

Remove the ISDN (mISDN, CAPI) subsystem and Bluetooth CMTP protocol from the kernel tree. ISDN is a pretty old technology and it's unclear whether anyone still uses it. I went over the last few years of git history and all the commits are either tree-wide conversions or syzbot/static analyzer fixes. When we discussed removal in the past IIRC there were some concerns about ISDN still being used in parts of Germany. Unfortunately, the code base is quite old, none of the current maintainers are familiar with it and AI tools will have a field day finding bugs here. Delete this code and preserve it in an out-of-tree repository for any remaining users: https://github.com/linux-netdev/mod-orphan UAPI constants AF_ISDN/PF_ISDN and the SELinux isdn_socket class are preserved for ABI stability, but the rest of uAPI is removed. Signed-off-by: Jakub Kicinski Acked-by: Greg Kroah-Hartman Acked-by: Stephen Hemminger Acked-by: Luiz Augusto von Dentz Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260421022108.1299678-1-kuba@kernel.org Signed-off-by: Paolo Abeni

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

mISDN: Delete unnecessary checks before the macro call “dev_kfree_skb”

2019-08-22T23:22:03+00:00

The dev_kfree_skb() function performs also input parameter validation. Thus the test around the shown calls is not needed. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring Signed-off-by: David S. Miller

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174

2019-05-30T18:26:41+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 655 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Kate Stewart Reviewed-by: Richard Fontana Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de Signed-off-by: Greg Kroah-Hartman

mISDN: Fix null pointer dereference at mISDN_FsmNew

2017-08-11T21:56:23+00:00

If mISDN_FsmNew() fails to allocate memory for jumpmatrix then null pointer dereference will occur on any write to jumpmatrix. The patch adds check on successful allocation and corresponding error handling. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Anton Vasilyev Signed-off-by: David S. Miller

networking: introduce and use skb_put_data()

2017-06-16T15:48:37+00:00

A common pattern with skb_put() is to just want to memcpy() some data into the new space, introduce skb_put_data() for this. An spatch similar to the one for skb_put_zero() converts many of the places using it: @@ identifier p, p2; expression len, skb, data; type t, t2; @@ ( -p = skb_put(skb, len); +p = skb_put_data(skb, data, len); | -p = (t)skb_put(skb, len); +p = skb_put_data(skb, data, len); ) ( p2 = (t2)p; -memcpy(p2, data, len); | -memcpy(p, data, len); ) @@ type t, t2; identifier p, p2; expression skb, data; @@ t *p; ... ( -p = skb_put(skb, sizeof(t)); +p = skb_put_data(skb, data, sizeof(t)); | -p = (t *)skb_put(skb, sizeof(t)); +p = skb_put_data(skb, data, sizeof(t)); ) ( p2 = (t2)p; -memcpy(p2, data, sizeof(*p)); | -memcpy(p, data, sizeof(*p)); ) @@ expression skb, len, data; @@ -memcpy(skb_put(skb, len), data, len); +skb_put_data(skb, data, len); (again, manually post-processed to retain some comments) Reviewed-by: Stephen Hemminger Signed-off-by: Johannes Berg Signed-off-by: David S. Miller

mISDN: fix OOM condition for sending queued I-Frames

2015-10-22T14:23:19+00:00

The old code did not check the return value of skb_clone(). The extra skb_clone() is not needed at all, if using skb_realloc_headroom() instead, which gives us a private copy with enough headroom as well. We need to requeue the original skb if the call failed, because we cannot inform upper layers about the data loss. Restructure the code to minimise rollback effort if it happens. This fix kernel bug #86091 Thanks to Insu Yun to remind me on this issue. Signed-off-by: Karsten Keil Signed-off-by: David S. Miller

mISDN: Bugfix for layer2 fixed TEI mode

2012-08-06T20:22:50+00:00

If a fixed TEI is used, the initial state of the layer 2 statmachine need to be 4 (TEI assigned). This was true only for Point to Point connections, but not for the other fixed TEIs. It was not found before, because usually only the TEI 0 is used as fixed TEI for PtP mode, but if you try X31 packet mode connections with SAPI 16, TEI 1, it did fail. Signed-off-by: Karsten Keil Cc: # 3.5.x Signed-off-by: David S. Miller

mISDN: Help to identify the card

2012-05-04T15:56:19+00:00

With multiple cards is hard to figure out which port caused trouble int the layer2 routines (e.g. got a timeout). Now we have the informations in the log output. Signed-off-by: Karsten Keil Signed-off-by: David S. Miller