kernel/drivers/net/arcnet/com20020-pci.c, branch linux-6.18.y

net: arcnet: com20020-pci: fix support for 2.5Mbit cards

2026-03-12T11:09:34Z

[ Upstream commit c7d9be66b71af490446127c6ffcb66d6bb71b8b9 ] Commit 8c14f9c70327 ("ARCNET: add com20020 PCI IDs with metadata") converted the com20020-pci driver to use a card info structure instead of a single flag mask in driver_data. However, it failed to take into account that in the original code, driver_data of 0 indicates a card with no special flags, not a card that should not have any card info structure. This introduced a null pointer dereference when cards with no flags were probed. Commit bd6f1fd5d33d ("net: arcnet: com20020: Fix null-ptr-deref in com20020pci_probe()") then papered over this issue by rejecting cards with no driver_data instead of resolving the problem at its source. Fix the original issue by introducing a new card info structure for 2.5Mbit cards that does not set any flags and using it if no driver_data is present. Fixes: 8c14f9c70327 ("ARCNET: add com20020 PCI IDs with metadata") Fixes: bd6f1fd5d33d ("net: arcnet: com20020: Fix null-ptr-deref in com20020pci_probe()") Cc: stable@vger.kernel.org Reviewed-by: Simon Horman Signed-off-by: Ethan Nelson-Moore Link: https://patch.msgid.link/20260213045510.32368-1-enelsonmoore@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

arcnet: Add NULL check in com20020pci_probe()

2025-04-04T14:30:51Z

devm_kasprintf() returns NULL when memory allocation fails. Currently, com20020pci_probe() does not check for this case, which results in a NULL pointer dereference. Add NULL check after devm_kasprintf() to prevent this issue and ensure no resources are left allocated. Fixes: 6b17a597fc2f ("arcnet: restoring support for multiple Sohard Arcnet cards") Signed-off-by: Henry Martin Link: https://patch.msgid.link/20250402135036.44697-1-bsdhenrymartin@gmail.com Signed-off-by: Jakub Kicinski

net: fill in MODULE_DESCRIPTION()s for missing arcnet

2024-02-15T16:03:46Z

W=1 builds now warn if module is built without a MODULE_DESCRIPTION(). Add descriptions to the ARC modules. Signed-off-by: Breno Leitao Link: https://lore.kernel.org/r/20240214152741.670178-8-leitao@debian.org Signed-off-by: Jakub Kicinski

arcnet: restoring support for multiple Sohard Arcnet cards

2023-12-05T02:01:20Z

Probe of Sohard Arcnet cards fails, if 2 or more cards are installed in a system. See kernel log: [ 2.759203] arcnet: arcnet loaded [ 2.763648] arcnet:com20020: COM20020 chipset support (by David Woodhouse et al.) [ 2.770585] arcnet:com20020_pci: COM20020 PCI support [ 2.772295] com20020 0000:02:00.0: enabling device (0000 -> 0003) [ 2.772354] (unnamed net_device) (uninitialized): PLX-PCI Controls ... [ 3.071301] com20020 0000:02:00.0 arc0-0 (uninitialized): PCI COM20020: station FFh found at F080h, IRQ 101. [ 3.071305] com20020 0000:02:00.0 arc0-0 (uninitialized): Using CKP 64 - data rate 2.5 Mb/s [ 3.071534] com20020 0000:07:00.0: enabling device (0000 -> 0003) [ 3.071581] (unnamed net_device) (uninitialized): PLX-PCI Controls ... [ 3.369501] com20020 0000:07:00.0: Led pci:green:tx:0-0 renamed to pci:green:tx:0-0_1 due to name collision [ 3.369535] com20020 0000:07:00.0: Led pci:red:recon:0-0 renamed to pci:red:recon:0-0_1 due to name collision [ 3.370586] com20020 0000:07:00.0 arc0-0 (uninitialized): PCI COM20020: station E1h found at C000h, IRQ 35. [ 3.370589] com20020 0000:07:00.0 arc0-0 (uninitialized): Using CKP 64 - data rate 2.5 Mb/s [ 3.370608] com20020: probe of 0000:07:00.0 failed with error -5 commit 5ef216c1f848 ("arcnet: com20020-pci: add rotary index support") changes the device name of all COM20020 based PCI cards, even if only some cards support this: snprintf(dev->name, sizeof(dev->name), "arc%d-%d", dev->dev_id, i); The error happens because all Sohard Arcnet cards would be called arc0-0, since the Sohard Arcnet cards don't have a PLX rotary coder. I.e. EAE Arcnet cards have a PLX rotary coder, which sets the first decimal, ensuring unique devices names. This patch adds two new card feature flags to indicate which cards support LEDs and the PLX rotary coder. For EAE based cards the names still depend on the PLX rotary coder (untested, since missing EAE hardware). For Sohard based cards, this patch will result in devices being called arc0, arc1, ... (tested). Signed-off-by: Thomas Reichinger Fixes: 5ef216c1f848 ("arcnet: com20020-pci: add rotary index support") Link: https://lore.kernel.org/r/20231130113503.6812-1-thomas.reichinger@sohard.de Signed-off-by: Jakub Kicinski

net: arcnet: com20020: Fix null-ptr-deref in com20020pci_probe()

2022-03-03T10:29:13Z

During driver initialization, the pointer of card info, i.e. the variable 'ci' is required. However, the definition of 'com20020pci_id_table' reveals that this field is empty for some devices, which will cause null pointer dereference when initializing these devices. The following log reveals it: [ 3.973806] KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] [ 3.973819] RIP: 0010:com20020pci_probe+0x18d/0x13e0 [com20020_pci] [ 3.975181] Call Trace: [ 3.976208] local_pci_probe+0x13f/0x210 [ 3.977248] pci_device_probe+0x34c/0x6d0 [ 3.977255] ? pci_uevent+0x470/0x470 [ 3.978265] really_probe+0x24c/0x8d0 [ 3.978273] __driver_probe_device+0x1b3/0x280 [ 3.979288] driver_probe_device+0x50/0x370 Fix this by checking whether the 'ci' is a null pointer first. Fixes: 8c14f9c70327 ("ARCNET: add com20020 PCI IDs with metadata") Signed-off-by: Zheyu Ma Signed-off-by: David S. Miller

net: remove single-byte netdev->dev_addr writes

2021-10-13T17:03:59Z

Make the drivers which use single-byte netdev addresses (netdev->addr_len == 1) use the appropriate address setting helpers. arcnet copies from int variables and io reads a lot, so add a helper for arcnet drivers to use. Similar helper could be reused for phonet and appletalk but there isn't any good central location where we could put it, and netdevice.h is already very crowded. Acked-by: Sebastian Reichel # for HSI Link: https://lore.kernel.org/r/20211012142757.4124842-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

net: arcnet: com20020 fix error handling

2021-03-14T21:17:48Z

There are two issues when handling error case in com20020pci_probe() 1. priv might be not initialized yet when calling com20020pci_remove() from com20020pci_probe(), since the priv is set at the very last but it can jump to error handling in the middle and priv remains NULL. 2. memory leak - the net device is allocated in alloc_arcdev but not properly released if error happens in the middle of the big for loop [ 1.529110] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 1.531447] RIP: 0010:com20020pci_remove+0x15/0x60 [com20020_pci] [ 1.536805] Call Trace: [ 1.536939] com20020pci_probe+0x3f2/0x48c [com20020_pci] [ 1.537226] local_pci_probe+0x48/0x80 [ 1.539918] com20020pci_init+0x3f/0x1000 [com20020_pci] Signed-off-by: Tong Zhang Signed-off-by: David S. Miller

net: arcnet: Fix RESET flag handling

2021-01-30T04:54:06Z

The main arcnet interrupt handler calls arcnet_close() then arcnet_open(), if the RESET status flag is encountered. This is invalid: 1) In general, interrupt handlers should never call ->ndo_stop() and ->ndo_open() functions. They are usually full of blocking calls and other methods that are expected to be called only from drivers init and exit code paths. 2) arcnet_close() contains a del_timer_sync(). If the irq handler interrupts the to-be-deleted timer, del_timer_sync() will just loop forever. 3) arcnet_close() also calls tasklet_kill(), which has a warning if called from irq context. 4) For device reset, the sequence "arcnet_close(); arcnet_open();" is not complete. Some children arcnet drivers have special init/exit code sequences, which then embed a call to arcnet_open() and arcnet_close() accordingly. Check drivers/net/arcnet/com20020.c. Run the device RESET sequence from a scheduled workqueue instead. Signed-off-by: Ahmed S. Darwish Signed-off-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20210128194802.727770-1-a.darwish@linutronix.de Signed-off-by: Jakub Kicinski

arcnet: com20020-pci: constify attribute_group structures.

2017-07-18T19:04:56Z

attribute_group are not supposed to change at runtime. All functions working with attribute_group provided by work with const attribute_group. So mark the non-const structs as const. File size before: text data bss dec hex filename 3409 948 28 4385 1121 drivers/net/arcnet/com20020-pci.o File size After adding 'const': text data bss dec hex filename 3473 884 28 4385 1121 drivers/net/arcnet/com20020-pci.o Signed-off-by: Arvind Yadav Signed-off-by: David S. Miller

arcnet: com20020-pci: Fix an error handling path in 'com20020pci_probe()'

2017-07-07T08:29:10Z

If this memory allocation fails, we should go through the error handling path as done everywhere else in this function before returning. Signed-off-by: Christophe JAILLET Signed-off-by: David S. Miller