kernel/linux.git/drivers/net/wan, branch linux-5.11.y

net: lapbether: Prevent racing when checking whether the netif is running

2021-05-14T08:50:00+00:00

[ Upstream commit 5acd0cfbfbb5a688da1bfb1a2152b0c855115a35 ] There are two "netif_running" checks in this driver. One is in "lapbeth_xmit" and the other is in "lapbeth_rcv". They serve to make sure that the LAPB APIs called in these functions are called before "lapb_unregister" is called by the "ndo_stop" function. However, these "netif_running" checks are unreliable, because it's possible that immediately after "netif_running" returns true, "ndo_stop" is called (which causes "lapb_unregister" to be called). This patch adds locking to make sure "lapbeth_xmit" and "lapbeth_rcv" can reliably check and ensure the netif is running while doing their work. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xie He Acked-by: Martin Schiller Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

Revert "drivers/net/wan/hdlc_fr: Fix a double free in pvc_xmit"

2021-05-14T08:49:32+00:00

commit d362fd0be456dba2d3d58a90b7a193962776562b upstream. This reverts commit 1b479fb80160 ("drivers/net/wan/hdlc_fr: Fix a double free in pvc_xmit"). 1. This commit is incorrect. "__skb_pad" will NOT free the skb on failure when its "free_on_error" parameter is "false". 2. This commit claims to fix my commit. But it didn't CC me?? Fixes: 1b479fb80160 ("drivers/net/wan/hdlc_fr: Fix a double free in pvc_xmit") Cc: Lv Yunlong Signed-off-by: Xie He Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

drivers/net/wan/hdlc_fr: Fix a double free in pvc_xmit

2021-04-14T06:47:18+00:00

[ Upstream commit 1b479fb801602b22512f53c19b1f93a4fc5d5d9d ] In pvc_xmit, if __skb_pad(skb, pad, false) failed, it will free the skb in the first time and goto drop. But the same skb is freed by kfree_skb(skb) in the second time in drop. Maintaining the original function unchanged, my patch adds a new label out to avoid the double free if __skb_pad() failed. Fixes: f5083d0cee08a ("drivers/net/wan/hdlc_fr: Improvements to the code of pvc_xmit") Signed-off-by: Lv Yunlong Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: wan/lmc: unregister device when no matching device is found

2021-04-07T13:02:29+00:00

[ Upstream commit 62e69bc419772638369eff8ff81340bde8aceb61 ] lmc set sc->lmc_media pointer when there is a matching device. However, when no matching device is found, this pointer is NULL and the following dereference will result in a null-ptr-deref. To fix this issue, unregister the hdlc device and return an error. [ 4.569359] BUG: KASAN: null-ptr-deref in lmc_init_one.cold+0x2b6/0x55d [lmc] [ 4.569748] Read of size 8 at addr 0000000000000008 by task modprobe/95 [ 4.570102] [ 4.570187] CPU: 0 PID: 95 Comm: modprobe Not tainted 5.11.0-rc7 #94 [ 4.570527] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-48-gd9c812dda519-preb4 [ 4.571125] Call Trace: [ 4.571261] dump_stack+0x7d/0xa3 [ 4.571445] kasan_report.cold+0x10c/0x10e [ 4.571667] ? lmc_init_one.cold+0x2b6/0x55d [lmc] [ 4.571932] lmc_init_one.cold+0x2b6/0x55d [lmc] [ 4.572186] ? lmc_mii_readreg+0xa0/0xa0 [lmc] [ 4.572432] local_pci_probe+0x6f/0xb0 [ 4.572639] pci_device_probe+0x171/0x240 [ 4.572857] ? pci_device_remove+0xe0/0xe0 [ 4.573080] ? kernfs_create_link+0xb6/0x110 [ 4.573315] ? sysfs_do_create_link_sd.isra.0+0x76/0xe0 [ 4.573598] really_probe+0x161/0x420 [ 4.573799] driver_probe_device+0x6d/0xd0 [ 4.574022] device_driver_attach+0x82/0x90 [ 4.574249] ? device_driver_attach+0x90/0x90 [ 4.574485] __driver_attach+0x60/0x100 [ 4.574694] ? device_driver_attach+0x90/0x90 [ 4.574931] bus_for_each_dev+0xe1/0x140 [ 4.575146] ? subsys_dev_iter_exit+0x10/0x10 [ 4.575387] ? klist_node_init+0x61/0x80 [ 4.575602] bus_add_driver+0x254/0x2a0 [ 4.575812] driver_register+0xd3/0x150 [ 4.576021] ? 0xffffffffc0018000 [ 4.576202] do_one_initcall+0x84/0x250 [ 4.576411] ? trace_event_raw_event_initcall_finish+0x150/0x150 [ 4.576733] ? unpoison_range+0xf/0x30 [ 4.576938] ? ____kasan_kmalloc.constprop.0+0x84/0xa0 [ 4.577219] ? unpoison_range+0xf/0x30 [ 4.577423] ? unpoison_range+0xf/0x30 [ 4.577628] do_init_module+0xf8/0x350 [ 4.577833] load_module+0x3fe6/0x4340 [ 4.578038] ? vm_unmap_ram+0x1d0/0x1d0 [ 4.578247] ? ____kasan_kmalloc.constprop.0+0x84/0xa0 [ 4.578526] ? module_frob_arch_sections+0x20/0x20 [ 4.578787] ? __do_sys_finit_module+0x108/0x170 [ 4.579037] __do_sys_finit_module+0x108/0x170 [ 4.579278] ? __ia32_sys_init_module+0x40/0x40 [ 4.579523] ? file_open_root+0x200/0x200 [ 4.579742] ? do_sys_open+0x85/0xe0 [ 4.579938] ? filp_open+0x50/0x50 [ 4.580125] ? exit_to_user_mode_prepare+0xfc/0x130 [ 4.580390] do_syscall_64+0x33/0x40 [ 4.580586] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 4.580859] RIP: 0033:0x7f1a724c3cf7 [ 4.581054] Code: 48 89 57 30 48 8b 04 24 48 89 47 38 e9 1d a0 02 00 48 89 f8 48 89 f7 48 89 d6 48 891 [ 4.582043] RSP: 002b:00007fff44941c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [ 4.582447] RAX: ffffffffffffffda RBX: 00000000012ada70 RCX: 00007f1a724c3cf7 [ 4.582827] RDX: 0000000000000000 RSI: 00000000012ac9e0 RDI: 0000000000000003 [ 4.583207] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000001 [ 4.583587] R10: 00007f1a72527300 R11: 0000000000000246 R12: 00000000012ac9e0 [ 4.583968] R13: 0000000000000000 R14: 00000000012acc90 R15: 0000000000000001 [ 4.584349] ================================================================== Signed-off-by: Tong Zhang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: hdlc_x25: Prevent racing between "x25_close" and "x25_xmit"/"x25_rx"

2021-03-30T12:30:20+00:00

[ Upstream commit bf0ffea336b493c0a8c8bc27b46683ecf1e8f294 ] "x25_close" is called by "hdlc_close" in "hdlc.c", which is called by hardware drivers' "ndo_stop" function. "x25_xmit" is called by "hdlc_start_xmit" in "hdlc.c", which is hardware drivers' "ndo_start_xmit" function. "x25_rx" is called by "hdlc_rcv" in "hdlc.c", which receives HDLC frames from "net/core/dev.c". "x25_close" races with "x25_xmit" and "x25_rx" because their callers race. However, we need to ensure that the LAPB APIs called in "x25_xmit" and "x25_rx" are called before "lapb_unregister" is called in "x25_close". This patch adds locking to ensure when "x25_xmit" and "x25_rx" are doing their work, "lapb_unregister" is not yet called in "x25_close". Reasons for not solving the racing between "x25_close" and "x25_xmit" by calling "netif_tx_disable" in "x25_close": 1. We still need to solve the racing between "x25_close" and "x25_rx"; 2. The design of the HDLC subsystem assumes the HDLC hardware drivers have full control over the TX queue, and the HDLC protocol drivers (like this driver) have no control. Controlling the queue here in the protocol driver may interfere with hardware drivers' control of the queue. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xie He Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: wan: fix error return code of uhdlc_init()

2021-03-30T12:30:08+00:00

[ Upstream commit 62765d39553cfd1ad340124fe1e280450e8c89e2 ] When priv->rx_skbuff or priv->tx_skbuff is NULL, no error return code of uhdlc_init() is assigned. To fix this bug, ret is assigned with -ENOMEM in these cases. Reported-by: TOTE Robot Signed-off-by: Jia-Ju Bai Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: lapbether: Remove netif_start_queue / netif_stop_queue

2021-03-17T16:11:24+00:00

commit f7d9d4854519fdf4d45c70a4d953438cd88e7e58 upstream. For the devices in this driver, the default qdisc is "noqueue", because their "tx_queue_len" is 0. In function "__dev_queue_xmit" in "net/core/dev.c", devices with the "noqueue" qdisc are specially handled. Packets are transmitted without being queued after a "dev->flags & IFF_UP" check. However, it's possible that even if this check succeeds, "ops->ndo_stop" may still have already been called. This is because in "__dev_close_many", "ops->ndo_stop" is called before clearing the "IFF_UP" flag. If we call "netif_stop_queue" in "ops->ndo_stop", then it's possible in "__dev_queue_xmit", it sees the "IFF_UP" flag is present, and then it checks "netif_xmit_stopped" and finds that the queue is already stopped. In this case, it will complain that: "Virtual device ... asks to queue packet!" To prevent "__dev_queue_xmit" from generating this complaint, we should not call "netif_stop_queue" in "ops->ndo_stop". We also don't need to call "netif_start_queue" in "ops->ndo_open", because after a netdev is allocated and registered, the "__QUEUE_STATE_DRV_XOFF" flag is initially not set, so there is no need to call "netif_start_queue" to clear it. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xie He Acked-by: Martin Schiller Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: hdlc_x25: Return meaningful error code in x25_open

2021-02-05T02:13:25+00:00

It's not meaningful to pass on LAPB error codes to HDLC code or other parts of the system, because they will not understand the error codes. Instead, use system-wide recognizable error codes. Fixes: f362e5fe0f1f ("wan/hdlc_x25: make lapb params configurable") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Xie He Acked-by: Martin Schiller Link: https://lore.kernel.org/r/20210203071541.86138-1-xie.he.0141@gmail.com Signed-off-by: Jakub Kicinski

wan: ds26522: select CONFIG_BITREVERSE

2021-01-05T23:50:36+00:00

Without this, the driver runs into a link failure arm-linux-gnueabi-ld: drivers/net/wan/slic_ds26522.o: in function `slic_ds26522_probe': slic_ds26522.c:(.text+0x100c): undefined reference to `byte_rev_table' arm-linux-gnueabi-ld: slic_ds26522.c:(.text+0x1cdc): undefined reference to `byte_rev_table' arm-linux-gnueabi-ld: drivers/net/wan/slic_ds26522.o: in function `slic_write': slic_ds26522.c:(.text+0x1e4c): undefined reference to `byte_rev_table' Fixes: c37d4a0085c5 ("Maxim/driver: Add driver for maxim ds26522") Signed-off-by: Arnd Bergmann Signed-off-by: David S. Miller

net: hdlc_ppp: Fix issues when mod_timer is called while timer is running

2020-12-28T23:09:04+00:00

ppp_cp_event is called directly or indirectly by ppp_rx with "ppp->lock" held. It may call mod_timer to add a new timer. However, at the same time ppp_timer may be already running and waiting for "ppp->lock". In this case, there's no need for ppp_timer to continue running and it can just exit. If we let ppp_timer continue running, it may call add_timer. This causes kernel panic because add_timer can't be called with a timer pending. This patch fixes this problem. Fixes: e022c2f07ae5 ("WAN: new synchronous PPP implementation for generic HDLC.") Cc: Krzysztof Halasa Signed-off-by: Xie He Signed-off-by: David S. Miller