kernel/linux.git/net/appletalk, branch v5.10.257

net: appletalk: Fix use-after-free in AARP proxy probe

2025-08-28T14:22:30+00:00

[ Upstream commit 6c4a92d07b0850342d3becf2e608f805e972467c ] The AARP proxy‐probe routine (aarp_proxy_probe_network) sends a probe, releases the aarp_lock, sleeps, then re-acquires the lock. During that window an expire timer thread (__aarp_expire_timer) can remove and kfree() the same entry, leading to a use-after-free. race condition: cpu 0 | cpu 1 atalk_sendmsg() | atif_proxy_probe_device() aarp_send_ddp() | aarp_proxy_probe_network() mod_timer() | lock(aarp_lock) // LOCK!! timeout around 200ms | alloc(aarp_entry) and then call | proxies[hash] = aarp_entry aarp_expire_timeout() | aarp_send_probe() | unlock(aarp_lock) // UNLOCK!! lock(aarp_lock) // LOCK!! | msleep(100); __aarp_expire_timer(&proxies[ct]) | free(aarp_entry) | unlock(aarp_lock) // UNLOCK!! | | lock(aarp_lock) // LOCK!! | UAF aarp_entry !! ================================================================== BUG: KASAN: slab-use-after-free in aarp_proxy_probe_network+0x560/0x630 net/appletalk/aarp.c:493 Read of size 4 at addr ffff8880123aa360 by task repro/13278 CPU: 3 UID: 0 PID: 13278 Comm: repro Not tainted 6.15.2 #3 PREEMPT(full) Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1b0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xc1/0x630 mm/kasan/report.c:521 kasan_report+0xca/0x100 mm/kasan/report.c:634 aarp_proxy_probe_network+0x560/0x630 net/appletalk/aarp.c:493 atif_proxy_probe_device net/appletalk/ddp.c:332 [inline] atif_ioctl+0xb58/0x16c0 net/appletalk/ddp.c:857 atalk_ioctl+0x198/0x2f0 net/appletalk/ddp.c:1818 sock_do_ioctl+0xdc/0x260 net/socket.c:1190 sock_ioctl+0x239/0x6a0 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x194/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcb/0x250 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Allocated: aarp_alloc net/appletalk/aarp.c:382 [inline] aarp_proxy_probe_network+0xd8/0x630 net/appletalk/aarp.c:468 atif_proxy_probe_device net/appletalk/ddp.c:332 [inline] atif_ioctl+0xb58/0x16c0 net/appletalk/ddp.c:857 atalk_ioctl+0x198/0x2f0 net/appletalk/ddp.c:1818 Freed: kfree+0x148/0x4d0 mm/slub.c:4841 __aarp_expire net/appletalk/aarp.c:90 [inline] __aarp_expire_timer net/appletalk/aarp.c:261 [inline] aarp_expire_timeout+0x480/0x6e0 net/appletalk/aarp.c:317 The buggy address belongs to the object at ffff8880123aa300 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 96 bytes inside of freed 192-byte region [ffff8880123aa300, ffff8880123aa3c0) Memory state around the buggy address: ffff8880123aa200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880123aa280: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880123aa300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880123aa380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880123aa400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kito Xu (veritas501) Link: https://patch.msgid.link/20250717012843.880423-1-hxzene@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: appletalk: fix kerneldoc warnings

2025-08-28T14:22:30+00:00

[ Upstream commit 709565ae14aa2670d6b480be46720856e804af41 ] net/appletalk/aarp.c:68: warning: Function parameter or member 'dev' not described in 'aarp_entry' net/appletalk/aarp.c:68: warning: Function parameter or member 'expires_at' not described in 'aarp_entry' net/appletalk/aarp.c:68: warning: Function parameter or member 'hwaddr' not described in 'aarp_entry' net/appletalk/aarp.c:68: warning: Function parameter or member 'last_sent' not described in 'aarp_entry' net/appletalk/aarp.c:68: warning: Function parameter or member 'next' not described in 'aarp_entry' net/appletalk/aarp.c:68: warning: Function parameter or member 'packet_queue' not described in 'aarp_entry' net/appletalk/aarp.c:68: warning: Function parameter or member 'status' not described in 'aarp_entry' net/appletalk/aarp.c:68: warning: Function parameter or member 'target_addr' not described in 'aarp_entry' net/appletalk/aarp.c:68: warning: Function parameter or member 'xmit_count' not described in 'aarp_entry' net/appletalk/ddp.c:1422: warning: Function parameter or member 'dev' not described in 'atalk_rcv' net/appletalk/ddp.c:1422: warning: Function parameter or member 'orig_dev' not described in 'atalk_rcv' net/appletalk/ddp.c:1422: warning: Function parameter or member 'pt' not described in 'atalk_rcv' net/appletalk/ddp.c:1422: warning: Function parameter or member 'skb' not described in 'atalk_rcv' Signed-off-by: Andrew Lunn Link: https://lore.kernel.org/r/20201028005527.930388-1-andrew@lunn.ch Signed-off-by: Jakub Kicinski Stable-dep-of: 6c4a92d07b08 ("net: appletalk: Fix use-after-free in AARP proxy probe") Signed-off-by: Sasha Levin

net: appletalk: Fix device refcount leak in atrtr_create()

2025-07-17T16:27:58+00:00

[ Upstream commit 711c80f7d8b163d3ecd463cd96f07230f488e750 ] When updating an existing route entry in atrtr_create(), the old device reference was not being released before assigning the new device, leading to a device refcount leak. Fix this by calling dev_put() to release the old device reference before holding the new one. Fixes: c7f905f0f6d4 ("[ATALK]: Add missing dev_hold() to atrtr_create().") Signed-off-by: Kito Xu Link: https://patch.msgid.link/tencent_E1A26771CDAB389A0396D1681A90A49E5D09@qq.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

appletalk: Fix Use-After-Free in atalk_ioctl

2023-12-20T14:44:29+00:00

[ Upstream commit 189ff16722ee36ced4d2a2469d4ab65a8fee4198 ] Because atalk_ioctl() accesses sk->sk_receive_queue without holding a sk->sk_receive_queue.lock, it can cause a race with atalk_recvmsg(). A use-after-free for skb occurs with the following flow. ``` atalk_ioctl() -> skb_peek() atalk_recvmsg() -> skb_recv_datagram() -> skb_free_datagram() ``` Add sk->sk_receive_queue.lock to atalk_ioctl() to fix this issue. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Hyunwoo Kim Link: https://lore.kernel.org/r/20231213041056.GA519680@v4bel-B760M-AORUS-ELITE-AX Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

appletalk: Fix skb allocation size in loopback case

2021-04-07T13:00:08+00:00

[ Upstream commit 39935dccb21c60f9bbf1bb72d22ab6fd14ae7705 ] If a DDP broadcast packet is sent out to a non-gateway target, it is also looped back. There is a potential for the loopback device to have a longer hardware header length than the original target route's device, which can result in the skb not being created with enough room for the loopback device's hardware header. This patch fixes the issue by determining that a loopback will be necessary prior to allocating the skb, and if so, ensuring the skb has enough room. This was discovered while testing a new driver that creates a LocalTalk network interface (LTALK_HLEN = 1). It caused an skb_under_panic. Signed-off-by: Doug Brown Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

appletalk: Fix atalk_proc_init() return path

2020-08-03T22:48:32+00:00

Add a missing return statement to atalk_proc_init so it doesn't return -ENOMEM when successful. This allows the appletalk module to load properly. Fixes: e2bcd8b0ce6e ("appletalk: use remove_proc_subtree to simplify procfs code") Link: https://www.downtowndougbrown.com/2020/08/hacking-up-a-fix-for-the-broken-appletalk-kernel-module-in-linux-5-1-and-newer/ Reported-by: Christopher KOBAYASHI Reported-by: Doug Brown Signed-off-by: Vincent Duvert [lukas: add missing tags] Signed-off-by: Lukas Wunner Cc: stable@vger.kernel.org # v5.1+ Cc: Yue Haibing Signed-off-by: David S. Miller

net: make ->{get,set}sockopt in proto_ops optional

2020-07-20T01:16:41+00:00

Just check for a NULL method instead of wiring up sock_no_{get,set}sockopt. Signed-off-by: Christoph Hellwig Acked-by: Marc Kleine-Budde Signed-off-by: David S. Miller

ipv4,appletalk: move SIOCADDRT and SIOCDELRT handling into ->compat_ioctl

2020-05-19T00:35:02+00:00

To prepare removing the global routing_ioctl hack start lifting the code into the ipv4 and appletalk ->compat_ioctl handlers. Unlike the existing handler we don't bother copying in the name - there are no compat issues for char arrays. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

appletalk: factor out a atrtr_ioctl_addrt helper

2020-05-19T00:35:02+00:00

Add a helper than can be shared with the upcoming compat ioctl handler. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

appletalk: enforce CAP_NET_RAW for raw sockets

2019-09-24T14:37:18+00:00

When creating a raw AF_APPLETALK socket, CAP_NET_RAW needs to be checked first. Signed-off-by: Ori Nimron Signed-off-by: Greg Kroah-Hartman Signed-off-by: David S. Miller