kernel/linux.git/drivers/usb/gadget/function/u_ether.c, branch v6.12.80

usb: gadget: f_ncm: Fix net_device lifecycle with device_move

2026-03-25T10:08:41+00:00

[ Upstream commit ec35c1969650e7cb6c8a91020e568ed46e3551b0 ] The network device outlived its parent gadget device during disconnection, resulting in dangling sysfs links and null pointer dereference problems. A prior attempt to solve this by removing SET_NETDEV_DEV entirely [1] was reverted due to power management ordering concerns and a NO-CARRIER regression. A subsequent attempt to defer net_device allocation to bind [2] broke 1:1 mapping between function instance and network device, making it impossible for configfs to report the resolved interface name. This results in a regression where the DHCP server fails on pmOS. Use device_move to reparent the net_device between the gadget device and /sys/devices/virtual/ across bind/unbind cycles. This preserves the network interface across USB reconnection, allowing the DHCP server to retain their binding. Introduce gether_attach_gadget()/gether_detach_gadget() helpers and use __free(detach_gadget) macro to undo attachment on bind failure. The bind_count ensures device_move executes only on the first bind. [1] https://lore.kernel.org/lkml/f2a4f9847617a0929d62025748384092e5f35cce.camel@crapouillou.net/ [2] https://lore.kernel.org/linux-usb/795ea759-7eaf-4f78-81f4-01ffbf2d7961@ixit.cz/ Fixes: 40d133d7f542 ("usb: gadget: f_ncm: convert to new function interface with backward compatibility") Cc: stable Signed-off-by: Kuen-Han Tsai Link: https://patch.msgid.link/20260309-f-ncm-revert-v2-7-ea2afbc7d9b2@google.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_ether: Set is_suspend flag if remote wakeup fails

2025-03-13T12:02:11+00:00

commit 17c2c87c37862c3e95b55f660681cc6e8d66660e upstream. Currently while UDC suspends, u_ether attempts to remote wakeup the host if there are any pending transfers. However, if remote wakeup fails, the UDC remains suspended but the is_suspend flag is not set. And since is_suspend flag isn't set, the subsequent eth_start_xmit() would queue USB requests to suspended UDC. To fix this, bail out from gether_suspend() only if remote wakeup operation is successful. Cc: stable Fixes: 0a1af6dfa077 ("usb: gadget: f_ecm: Add suspend/resume and remote wakeup support") Signed-off-by: Prashanth K Link: https://lore.kernel.org/r/20250212100840.3812153-1-prashanth.k@oss.qualcomm.com Signed-off-by: Greg Kroah-Hartman

Merge 6.10-rc6 into usb-next

2024-07-01T11:59:29+00:00

We need the USB fixes in here as well for some follow-on patches. Signed-off-by: Greg Kroah-Hartman

Revert "usb: gadget: u_ether: Replace netif_stop_queue with netif_device_detach"

2024-06-27T14:24:25+00:00

This reverts commit f49449fbc21e7e9550a5203902d69c8ae7dfd918. This commit breaks u_ether on some setups (at least Merrifield). The fix "usb: gadget: u_ether: Re-attach netif device to mirror detachment" party restores u-ether. However the netif usb: remains up even usb is switched from device to host mode. This creates problems for user space as the interface remains in the routing table while not realy present and network managers (connman) not detecting a network change. Various attempts to find the root cause were unsuccesful up to now. Therefore revert until a solution is found. Link: https://lore.kernel.org/linux-usb/20231006141231.7220-1-hgajjar@de.adit-jv.com/ Reported-by: Andy Shevchenko Reported-by: Ferry Toth Fixes: f49449fbc21e ("usb: gadget: u_ether: Replace netif_stop_queue with netif_device_detach") Cc: stable@vger.kernel.org Signed-off-by: Ferry Toth Link: https://lore.kernel.org/r/20240620204832.24518-3-ftoth@exalondelft.nl Signed-off-by: Greg Kroah-Hartman

Revert "usb: gadget: u_ether: Re-attach netif device to mirror detachment"

2024-06-27T14:24:25+00:00

This reverts commit 76c945730cdffb572c7767073cc6515fd3f646b4. Prerequisite revert for the reverting of the original commit f49449fbc21e. Fixes: 76c945730cdf ("usb: gadget: u_ether: Re-attach netif device to mirror detachment") Fixes: f49449fbc21e ("usb: gadget: u_ether: Replace netif_stop_queue with netif_device_detach") Reported-by: Ferry Toth Cc: stable@vger.kernel.org Signed-off-by: Ferry Toth Link: https://lore.kernel.org/r/20240620204832.24518-2-ftoth@exalondelft.nl Signed-off-by: Greg Kroah-Hartman

usb: gadget: add missing MODULE_DESCRIPTION() macros

2024-06-20T17:18:19+00:00

make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/libcomposite.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_acm.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_ss_lb.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/u_serial.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_serial.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_obex.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/u_ether.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_ncm.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_ecm.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_phonet.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_eem.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_ecm_subset.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_rndis.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_mass_storage.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_fs.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_uac1.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_uac1_legacy.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_uac2.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_uvc.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_midi.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_midi2.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_hid.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_printer.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/function/usb_f_tcm.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/legacy/g_zero.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/legacy/g_midi.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/usb/gadget/legacy/g_dbgp.o Add the missing invocations of the MODULE_DESCRIPTION() macro. Signed-off-by: Jeff Johnson Link: https://lore.kernel.org/r/20240605-md-drivers-usb-gadget-v1-1-29847a46aad3@quicinc.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_ether: replace deprecated strncpy with strscpy

2024-03-26T09:44:29+00:00

strncpy() is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. Let's use the new 2-argument strscpy() as this guarantees NUL-termination on the destination buffer and also uses the destination buffer's size to bound the operation. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2] Link: https://github.com/KSPP/linux/issues/90 Cc: linux-hardening@vger.kernel.org Signed-off-by: Justin Stitt Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20240318-strncpy-drivers-usb-gadget-function-u_ether-c-v1-1-e8543a1db24a@google.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: constify the struct device_type usage

2024-02-19T08:35:46+00:00

Since commit aed65af1cc2f ("drivers: make device_type const"), the driver core can properly handle constant struct device_type. Move the gadget_type variable to be a constant structure as well, placing it into read-only memory which can not be modified at runtime. Signed-off-by: Ricardo B. Marliere Link: https://lore.kernel.org/r/20240218-device_cleanup-usb-v1-3-77423c4da262@marliere.net Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_ether: Re-attach netif device to mirror detachment

2024-01-04T15:04:28+00:00

In 6.7-rc1, there was a netif_device_detach call added to the gether_disconnect function. This clears the __LINK_STATE_PRESENT bit of the netif device and suppresses pings (ICMP messages) and TCP connection requests from the connected host. If userspace temporarily disconnects the gadget, such as by temporarily removing configuration in the gadget configfs interface, network activity should continue to be processed when the gadget is re-connected. Mirror the netif_device_detach call with a netif_device_attach call in gether_connect to fix re-connecting gadgets. Link: https://gitlab.com/postmarketOS/pmaports/-/tree/6002e51b7090aeeb42947e0ca7ec22278d7227d0/main/postmarketos-base-ui/rootfs-usr-lib-NetworkManager-dispatcher.d-50-tethering.sh Cc: stable Fixes: f49449fbc21e ("usb: gadget: u_ether: Replace netif_stop_queue with netif_device_detach") Signed-off-by: Richard Acayan Tested-by: Luca Weiss Tested-by: Duje Mihanović Link: https://lore.kernel.org/r/20231218164532.411125-2-mailingradian@gmail.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: u_ether: Replace netif_stop_queue with netif_device_detach

2023-10-08T05:50:36+00:00

This patch replaces the usage of netif_stop_queue with netif_device_detach in the u_ether driver. The netif_device_detach function not only stops all tx queues by calling netif_tx_stop_all_queues but also marks the device as removed by clearing the __LINK_STATE_PRESENT bit. This change helps notify user space about the disconnection of the device more effectively, compared to netif_stop_queue, which only stops a single transmit queue. Signed-off-by: Hardik Gajjar Link: https://lore.kernel.org/r/20231006155646.12938-1-hgajjar@de.adit-jv.com Signed-off-by: Greg Kroah-Hartman