On 19.09.22 17:01, Lech Perczak wrote:
From: Paweł Lenkow <pawel.lenkow@xxxxxxxxxxxxxxx> During our testing of WFM200 module over SDIO on i.MX6Q-based platform, we discovered a memory corruption on the system, tracing back to the wfx driver. Using kfence, it was possible to trace it back to the root cause, which is hw->max_rates set to 8 in wfx_init_common, while the maximum defined by IEEE80211_TX_TABLE_SIZE is 4. This causes array out-of-bounds writes during updates of the rate table, as seen below: BUG: KFENCE: memory corruption in kfree_rcu_work+0x320/0x36c Corrupted memory at 0xe0a4ffe0 [ 0x03 0x03 0x03 0x03 0x01 0x00 0x00 0x02 0x02 0x02 0x09 0x00 0x21 0xbb 0xbb 0xbb ] (in kfence-#81): kfree_rcu_work+0x320/0x36c process_one_work+0x3ec/0x920 worker_thread+0x60/0x7a4 kthread+0x174/0x1b4 ret_from_fork+0x14/0x2c 0x0 kfence-#81: 0xe0a4ffc0-0xe0a4ffdf, size=32, cache=kmalloc-64 allocated by task 297 on cpu 0 at 631.039555s: minstrel_ht_update_rates+0x38/0x2b0 [mac80211] rate_control_tx_status+0xb4/0x148 [mac80211] ieee80211_tx_status_ext+0x364/0x1030 [mac80211] ieee80211_tx_status+0xe0/0x118 [mac80211] ieee80211_tasklet_handler+0xb0/0xe0 [mac80211] tasklet_action_common.constprop.0+0x11c/0x148 __do_softirq+0x1a4/0x61c irq_exit+0xcc/0x104 call_with_stack+0x18/0x20 __irq_svc+0x80/0xb0 wq_worker_sleeping+0x10/0x100 wq_worker_sleeping+0x10/0x100 schedule+0x50/0xe0 schedule_timeout+0x2e0/0x474 wait_for_completion+0xdc/0x1ec mmc_wait_for_req_done+0xc4/0xf8 mmc_io_rw_extended+0x3b4/0x4ec sdio_io_rw_ext_helper+0x290/0x384 sdio_memcpy_toio+0x30/0x38 wfx_sdio_copy_to_io+0x88/0x108 [wfx] wfx_data_write+0x88/0x1f0 [wfx] bh_work+0x1c8/0xcc0 [wfx] process_one_work+0x3ec/0x920 worker_thread+0x60/0x7a4 kthread+0x174/0x1b4 ret_from_fork+0x14/0x2c 0x0 After discussion on the wireless mailing list it was clarified that the issue has been introduced by: commit ee0e16ab756a ("mac80211: minstrel_ht: fill all requested rates") and fix shall be in minstrel_ht_update_rates in rc80211_minstrel_ht.c. Fixes: ee0e16ab756a ("mac80211: minstrel_ht: fill all requested rates") Link: https://lore.kernel.org/all/12e5adcd-8aed-f0f7-70cc-4fb7b656b829@xxxxxxxxxxxxxxx/ Link: https://lore.kernel.org/linux-wireless/20220915131445.30600-1-lech.perczak@xxxxxxxxxxxxxxx/ Cc: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx> Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx> Cc: Peter Seiderer <ps.report@xxxxxxx> Cc: Kalle Valo <kvalo@xxxxxxxxxx> Cc: Krzysztof Drobiński <krzysztof.drobinski@xxxxxxxxxxxxxxx>, Signed-off-by: Paweł Lenkow <pawel.lenkow@xxxxxxxxxxxxxxx> Signed-off-by: Lech Perczak <lech.perczak@xxxxxxxxxxxxxxx>
Acked-by: Felix Fietkau <nbd@xxxxxxxx> Thanks, - Felix