kernel/git/stable/linux.git/drivers/i2c, branch linux-5.15.y

i2c: mux: demux-pinctrl: fix OF node leak on kstrdup failure

2026-09-14T11:20:18+00:00

commit 62edb8ca0aa44517cc23cfa26cd8a51f15ea92fe upstream. of_parse_phandle() takes a reference on the parent node. If a later devm_kstrdup() fails, err_rollback only releases nodes for indices 0..i-1, so the current node is leaked. of_node_put() the current parent before rolling back. Fixes: 7c0195fa9a9e ("i2c: mux: demux-pinctrl: check the return value of devm_kstrdup()") Signed-off-by: Linkai Gong Cc: # v6.6+ Signed-off-by: Andi Shyti Link: https://patch.msgid.link/20260813095617.2246320-1-gonglinkai@kylinos.cn Signed-off-by: Greg Kroah-Hartman

i2c: mux: Fix channel node leak on adapter add failure

2026-09-14T11:20:17+00:00

commit 385c7af4e3b95d0769fd211831674e83b16a2ebf upstream. i2c_mux_add_adapter() takes a reference to the Device Tree channel node before registering the new adapter. If adapter registration fails, the error path frees the private data without dropping that reference. Release the channel node before freeing the private data. Fixes: bc45449b1444 ("i2c/of: Automatically populate i2c mux busses from device tree data.") Signed-off-by: Ahmad Byagowi Cc: # v3.5+ Acked-by: Peter Rosin Signed-off-by: Andi Shyti Link: https://patch.msgid.link/b3e46bbee781b3cb4029aca9a71316cc5e36dc17.1787502619.git.ahmadexp@gmail.com Signed-off-by: Greg Kroah-Hartman

i2c: core: fix debugfs UAF on adapter removal

2026-09-14T11:20:17+00:00

commit b15b548d52b43ba8ac4652bc2c7244a8dd1e9622 upstream. i2c_del_adapter() frees the adapter's debugfs directory before it unregisters the adapter device, but the new_device sysfs attribute stays writable until device_del(). A write racing with removal still reaches i2c_device_probe(), which passes the freed adap->debugfs to debugfs_create_dir() as the new client's parent: BUG: KASAN: slab-use-after-free in lookup_noperm_common+0x407/0x430 Read of size 4 at addr ffff88803ef87810 by task syz.0.61/6090 lookup_noperm_common+0x407/0x430 simple_start_creating+0x9c/0x110 debugfs_start_creating+0xdb/0x1a0 debugfs_create_dir+0x24/0x350 i2c_device_probe+0x814/0xbf0 It's technically possible to create a client after i2c_deregister_clients has run. That client will never be unregistered and make wait_for_completion hang. Close the window by removing the new_device attribute at the start of i2c_del_adapter(). device_remove_file() will drain any clients left. Fixes: 73febd775bdb ("i2c: create debugfs entry per adapter") Reported-by: syzbot+23ad911c819b923238b7@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=23ad911c819b923238b7 Signed-off-by: Vasileios Almpanis Cc: # v6.8+ Tested-by: syzbot+23ad911c819b923238b7@syzkaller.appspotmail.com Signed-off-by: Andi Shyti Link: https://patch.msgid.link/20260812-i2c-v2-1-5efaab4c3334@gmail.com Signed-off-by: Greg Kroah-Hartman

i2c: iproc: reset bus after timeout if START_BUSY is stuck

2026-08-23T12:17:30+00:00

[ Upstream commit 98f2e9e6d6f91a6abb43f166b244b428ba85fa2b ] If a transaction times out, the START_BUSY signal can stay up, and subsequent transactaction attempts will fail as the bus is still considered busy. I can easily trigger this by attempting to read from an address with no device, e.g. when running i2cdetect. After the first read times out, all subsequent read attempts return busy. To get to a working state again, the controller needs to be reset to clear the START_BUSY signal. So check for START_BUSY still asserted on a timeout, and do reset in case it is, This is also done by the original non-upstream iproc-smbus driver implementation [1]. Works around situations like: bcm-iproc-2c 1803b000.i2c: transaction timed out bcm-iproc-2c 1803b000.i2c: bus is busy bcm-iproc-2c 1803b000.i2c: bus is busy bcm-iproc-2c 1803b000.i2c: bus is busy bcm-iproc-2c 1803b000.i2c: bus is busy bcm-iproc-2c 1803b000.i2c: bus is busy ... where the bus never recovers after a timeout. [1] https://github.com/opencomputeproject/onie/blob/master/patches/kernel/3.2.69/driver-iproc-smbus.patch Fixes: e6e5dd3566e0 ("i2c: iproc: Add Broadcom iProc I2C Driver") Signed-off-by: Jonas Gorski Cc: # v4.0+ Acked-by: Ray Jui Signed-off-by: Andi Shyti Link: https://lore.kernel.org/r/20260717085507.34209-1-jonas.gorski@bisdn.de Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

i2c: bcm-iproc: remove printout on handled timeouts

2026-08-23T12:17:29+00:00

[ Upstream commit 796e2c260187e32530cf343546ba1cdf2e2f5491 ] I2C and SMBus timeouts are not something the user needs to be informed about on controller level. The client driver may know if that really is a problem and give more detailed information to the user. The controller should just pass this information upwards. Remove the printout. Signed-off-by: Wolfram Sang Signed-off-by: Andi Shyti Stable-dep-of: 98f2e9e6d6f9 ("i2c: iproc: reset bus after timeout if START_BUSY is stuck") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

i2c: imx: Fix slave registration race and error handling

2026-08-23T12:17:29+00:00

[ Upstream commit d64ec362c369bbc33833f7936d5f3a706b0d5c45 ] In i2c_imx_reg_slave(), the slave pointer was assigned before pm_runtime_resume_and_get(). If pm_runtime_resume_and_get() failed, the error path returned without clearing i2c_imx->slave, leaving it non-NULL and causing all subsequent registration attempts to fail with -EBUSY. Additionally, because this driver uses a shared IRQ, the interrupt handler i2c_imx_isr() can execute concurrently and, after acquiring slave_lock, dereference i2c_imx->slave. The previous fix attempt added a lockless i2c_imx->slave = NULL on the error path, but that could race with the ISR under the lock and still cause a NULL pointer dereference. Fix both issues by deferring the assignment of i2c_imx->slave and i2c_imx->last_slave_event to after a successful resume, and by performing the assignment inside the slave_lock critical section. This guarantees that the slave pointer is never left stale on the error path and is always valid when observed by the interrupt handler. Fixes: f7414cd6923f ("i2c: imx: support slave mode for imx I2C driver") Signed-off-by: Liem Cc: # v5.11+ Reviewed-by: Frank Li Acked-by: Carlos Song Signed-off-by: Andi Shyti Link: https://lore.kernel.org/r/20260629023829.152651-2-liem16213@gmail.com [ open-coded scoped_guard(spinlock_irqsave) into explicit spin_lock_irqsave/spin_unlock_irqrestore since 5.15 builds with -std=gnu89 ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

i2c: imx: fix locked bus on SMBus block-read of 0 (atomic)

2026-08-23T12:17:22+00:00

[ Upstream commit cb2fc37857693b55909fb77dc2c87cfbc1cdc476 ] SMBus 3.1 6.5.7 allows a Block Read byte count of 0, but the atomic (polling) path rejects it as -EPROTO. Worse, it returns without a NACK+STOP: the next receive cycle has already started, so the target keeps holding SDA and the bus stays stuck until a power cycle for this i2c controller. Reading I2DR to obtain the count likewise arms the next byte on the count > I2C_SMBUS_BLOCK_MAX path, which also returned -EPROTO directly and left the bus held. Handle both: NACK the in-flight dummy byte (TXAK) and extend msgs->len so the existing last-byte handling emits STOP; the dummy byte is discarded. A count of 0 is a valid empty block read; a count above I2C_SMBUS_BLOCK_MAX is still reported as -EPROTO, but only after the bus has been released. The interrupt-driven path has the same flaw from a later commit and is fixed separately, as it carries a different Fixes: tag and stable range. Fixes: 8e8782c71595 ("i2c: imx: add SMBus block read support") Signed-off-by: Vincent Jardin Cc: # v3.16+ Acked-by: Oleksij Rempel Acked-by: Carlos Song Reviewed-by: Stefan Eichenberger Signed-off-by: Andi Shyti Link: https://lore.kernel.org/r/20260713-for-upstream-i2c-lx2160-fix-v1-v3-1-073ac9e103a5@free.fr Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

i2c: imx: separate atomic, dma and non-dma use case

2026-08-23T12:17:22+00:00

[ Upstream commit b460b15b3cc23ef3639cc51043bf8b2a70ca1878 ] Separate the atomic, dma and non-dma use case as a preparation step for moving the non-dma use case to the isr to avoid rescheduling while a transfer is in progress. Signed-off-by: Stefan Eichenberger Reviewed-by: Frank Li Acked-by: Oleksij Rempel Signed-off-by: Andi Shyti Stable-dep-of: cb2fc3785769 ("i2c: imx: fix locked bus on SMBus block-read of 0 (atomic)") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

i2c: davinci: Unregister cpufreq notifier on probe failure

2026-08-23T12:17:17+00:00

[ Upstream commit e43f32816a1b1fe5a86279411626fe3a9be56d45 ] davinci_i2c_probe() registers a cpufreq transition notifier before adding the I2C adapter. If i2c_add_numbered_adapter() fails, the probe error path releases the device resources without unregistering the notifier. Add a dedicated error path to unregister the cpufreq notifier after i2c_add_numbered_adapter() fails. Fixes: 82c0de11b734 ("i2c: davinci: Add cpufreq support") Signed-off-by: Haoxiang Li Cc: # v2.6.36+ Reviewed-by: Bartosz Golaszewski Signed-off-by: Andi Shyti Link: https://lore.kernel.org/r/20260610030513.2651018-1-haoxiang_li2024@163.com Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

i2c: imx: Cancel hrtimer before clearing slave pointer

2026-08-19T15:14:11+00:00

commit 6ac7702b6cc2b94aaed9ef2d95bfbefcdc90061f upstream. In i2c_imx_unreg_slave(), the slave pointer is set to NULL after disabling interrupts. However, a pending interrupt might already have started the hrtimer (i2c_imx_slave_timeout) before the pointer was cleared. If the hrtimer fires after i2c_imx->slave is set to NULL, the timer callback i2c_imx_slave_finish_op() will call i2c_imx_slave_event() with a NULL slave pointer, which results in a use-after-free / NULL pointer dereference. Fix by canceling the hrtimer and waiting for it to complete after disabling interrupts, before clearing the slave pointer. Fixes: f7414cd6923f ("i2c: imx: support slave mode for imx I2C driver") Signed-off-by: Liem Cc: # v5.11+ Acked-by: Carlos Song Reviewed-by: Frank Li Signed-off-by: Andi Shyti Link: https://lore.kernel.org/r/20260629023829.152651-3-liem16213@gmail.com Signed-off-by: Greg Kroah-Hartman