kernel/git/stable/linux-stable.git/drivers/char/ipmi, branch linux-6.1.y

ipmi: si: Fix NULL pointer dereference after failed registration

2026-09-14T11:24:18+00:00

commit 6d920a75df9a83ab096b3cde7a643b656e4fdfeb upstream. try_smi_init() allocates new_smi->si_sm and later calls ipmi_register_smi_mod(), which maps to ipmi_add_smi(). During ipmi_add_smi(), the upper IPMI message handler obtains the initial BMC device information through __bmc_get_device_id(). This can fail if the BMC does not return a successful response to the Get Device ID command. When the BMC returns a nonzero completion code, the device-id helper retries the command and eventually returns -EIO if the device ID still cannot be fetched. On this failure path, ipmi_add_smi() logs "Unable to get the device id" and goes to out_err_started, where it invokes the lower driver's shutdown callback. try_smi_init() then logs the returned registration failure: ipmi_si IPI0001:00: IPMI message handler: Unable to get the device id: -5 ipmi_si IPI0001:00: Unable to register device: error -5 For ipmi_si, the shutdown callback is shutdown_smi(), which cleans up the SI state machine data, frees smi_info->si_sm, and sets smi_info->si_sm and smi_info->intf to NULL. However, intf->in_shutdown is not set on this failed-registration rollback path. Therefore, the asynchronous redo_bmc_reg work item can still retry BMC device-id probing after the lower driver has already cleared its SI state machine data. In the observed case, that retry path reached start_next_msg(), which passed the NULL smi_info->si_sm pointer to the selected KCS state machine handler: BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 Workqueue: events redo_bmc_reg [ipmi_msghandler] RIP: start_kcs_transaction+0x2c/0x190 [ipmi_si] Call Trace: start_next_msg+0x50/0x80 [ipmi_si] check_start_timer_thread.part.9+0x3b/0x50 [ipmi_si] sender+0x69/0x80 [ipmi_si] i_ipmi_request+0x2ac/0x9d0 [ipmi_msghandler] __get_device_id.isra.29+0xaa/0x180 [ipmi_msghandler] __bmc_get_device_id+0xef/0x950 [ipmi_msghandler] redo_bmc_reg+0x52/0x60 [ipmi_msghandler] process_one_work+0x1a7/0x360 Set intf->in_shutdown on the out_err_started path before invoking the lower driver's shutdown callback. This prevents later redo_bmc_reg retries from using an interface whose lower driver state has been cleaned up, and applies the same shutdown state to other IPMI interfaces as well. Fixes: 2512e40e48d2 ("ipmi: Rework SMI registration failure") Cc: stable@vger.kernel.org Signed-off-by: Seiji Nishikawa Message-ID: <20260630174348.1483814-1-snishika@redhat.com> Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi: ipmb: validate write message length

2026-09-14T11:24:18+00:00

commit 53637506884dbd5c91a89b1a3547d99d80f8ed2c upstream. ipmb_write() read message fields before validating the length byte. A zero or short write can read uninitialized stack bytes. A length smaller than the SMBus header underflows the block write length. Require a non-empty buffer and the minimum IPMB request length. Also require the length byte plus payload before parsing the message. Fixes: 51bd6f291583 ("Add support for IPMB driver") Cc: stable@vger.kernel.org Signed-off-by: Yousef Alhouseen Message-ID: <20260624175353.8592-1-alhouseenyousef@gmail.com> Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi: fix refcount leak in i_ipmi_request()

2026-08-23T12:18:27+00:00

[ Upstream commit a3f3859cecacb64f18fd446271ece9a3b3f2d4de ] When a caller provides a `supplied_recv` message to i_ipmi_request(), the function increments the user's `nr_msgs` reference count. If an error occurs later, the out_err cleanup path only frees the recv_msg if the function allocated it itself (i.e., !supplied_recv). In the supplied_recv case the cleanup is skipped, leaving the reference count elevated. The caller ipmi_request_supply_msgs() does not release the supplied_recv on error, so the reference is permanently leaked. Fix this by explicitly reverting the reference count operations when a supplied recv_msg with a valid user pointer is present in the error path: decrement nr_msgs and drop the user's kref. Cc: stable@vger.kernel.org Fixes: b52da4054ee0 ("ipmi: Rework user message limit handling") Signed-off-by: Wentao Liang Message-ID: <20260603120634.3758747-1-vulab@iscas.ac.cn> Signed-off-by: Corey Minyard [ changed `free_ipmi_user` to `free_user` in the two added `kref_put()` calls ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ipmi:ssif: NULL thread on error

2026-06-19T11:37:31+00:00

commit a8aebe93a4938c0ca1941eeaae821738f869be3d upstream. Cleanup code was checking the thread for NULL, but it was possibly a PTR_ERR() in one spot. Spotted with static analysis. Link: https://sourceforge.net/p/openipmi/mailman/message/59324676/ Fixes: 75c486cb1bca ("ipmi:ssif: Clean up kthread on errors") Cc: # 91eb7ec72612: ipmi:ssif: Remove unnecessary indention Cc: stable@vger.kernel.org Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi:ssif: Remove unnecessary indention

2026-06-19T11:37:31+00:00

commit 91eb7ec7261254b6875909df767185838598e21e upstream. A section was in {} that didn't need to be, move the variable definition to the top and set th eindentino properly. Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi:ssif: Clean up kthread on errors

2026-06-19T11:37:31+00:00

commit 75c486cb1bcaa1a3ec3a6438498176a3a4998ae4 upstream. If an error occurs after the ssif kthread is created, but before the main IPMI code starts the ssif interface, the ssif kthread will not be stopped. So make sure the kthread is stopped on an error condition if it is running. Fixes: 259307074bfc ("ipmi: Add SMBus interface driver (SSIF)") Reported-by: Li Xiao <<252270051@hdu.edu.cn> Cc: stable@vger.kernel.org Reviewed-by: Li Xiao <252270051@hdu.edu.cn> Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi:ssif: Fix a shutdown race

2026-06-19T11:37:31+00:00

commit 6bd0eb6d759b9a22c5509ea04e19c2e8407ba418 upstream. It was possible for the SSIF thread to stop and quit before the kthread_stop() call because ssif->stopping was set before the stop. So only exit the SSIF thread is kthread_should_stop() returns true. There is no need to wake the thread, as the wait will be interrupted by kthread_stop(). Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi: Fix rcu_read_unlock to srcu_read_unlock in handle_read_event_rsp

2026-06-19T11:37:10+00:00

Fix a bug where rcu_read_unlock() was used instead of srcu_read_unlock() in handle_read_event_rsp() when ipmi_alloc_recv_msg() fails. This mismatch leads to an SRCU read-side critical section imbalance: the entry uses srcu_read_lock(&intf->users_srcu) but the error path incorrectly calls rcu_read_unlock(), which is a no-op for SRCU and leaves the SRCU lock held. The offending code was restructured in mainline by commit 3be997d5a64a ("ipmi:msghandler: Remove srcu from the ipmi user structure"), which replaced the SRCU locking with a mutex in this function, effectively eliminating the mismatch. However, that commit is part of a larger SRCU removal series that is not suitable for stable backport. This minimal fix addresses the SRCU imbalance for 6.12 and earlier stable branches that still carry the original locking scheme. Fixes: e86ee2d44b44 ("ipmi: Rework locking and shutdown for hot remove") Cc: stable@vger.kernel.org Signed-off-by: Rui Qi Signed-off-by: Sasha Levin

ipmi:si: Return state to normal if message allocation fails

2026-06-01T15:38:53+00:00

commit 09dd798270ff582d7309f285d4aaf5dbebae01cb upstream. There were places where nothing would get started if a message allocation failed, so the driver needs to return to normal state. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman

ipmi: Check event message buffer response for bad data

2026-06-01T15:38:52+00:00

commit 36920f30e78e69df01f9691c470b6f3ba8aebf98 upstream. The event message buffer response data size got checked later when processing, but check it right after the response comes back. It appears some BMCs may return an empty message instead of an error when fetching events. There are apparently some new BMCs that make this error, so we need to compensate. Reported-by: Matt Fleming Closes: https://lore.kernel.org/lkml/20260415115930.3428942-1-matt@readmodwrite.com/ Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman