4.18-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 1db58529454742f67ebd96e3588315e880b72837 ]
reg_process_hint_country_ie() can free regulatory_request and return REG_REQ_ALREADY_SET. We shouldn't use regulatory_request after it's called. KASAN error was observed when this happens.
BUG: KASAN: use-after-free in reg_process_hint+0x839/0x8aa [cfg80211] Read of size 4 at addr ffff8800c430d434 by task kworker/1:3/89 <snipped> Workqueue: events reg_todo [cfg80211] Call Trace: dump_stack+0xc1/0x10c ? _atomic_dec_and_lock+0x1ad/0x1ad ? _raw_spin_lock_irqsave+0xa0/0xd2 print_address_description+0x86/0x26f ? reg_process_hint+0x839/0x8aa [cfg80211] kasan_report+0x241/0x29b reg_process_hint+0x839/0x8aa [cfg80211] reg_todo+0x204/0x5b9 [cfg80211] process_one_work+0x55f/0x8d0 ? worker_detach_from_pool+0x1b5/0x1b5 ? _raw_spin_unlock_irq+0x65/0xdd ? _raw_spin_unlock_irqrestore+0xf3/0xf3 worker_thread+0x5dd/0x841 ? kthread_parkme+0x1d/0x1d kthread+0x270/0x285 ? pr_cont_work+0xe3/0xe3 ? rcu_read_unlock_sched_notrace+0xca/0xca ret_from_fork+0x22/0x40
Allocated by task 2718: set_track+0x63/0xfa __kmalloc+0x119/0x1ac regulatory_hint_country_ie+0x38/0x329 [cfg80211] __cfg80211_connect_result+0x854/0xadd [cfg80211] cfg80211_rx_assoc_resp+0x3bc/0x4f0 [cfg80211] smsc95xx v1.0.6 ieee80211_sta_rx_queued_mgmt+0x1803/0x7ed5 [mac80211] ieee80211_iface_work+0x411/0x696 [mac80211] process_one_work+0x55f/0x8d0 worker_thread+0x5dd/0x841 kthread+0x270/0x285 ret_from_fork+0x22/0x40
Freed by task 89: set_track+0x63/0xfa kasan_slab_free+0x6a/0x87 kfree+0xdc/0x470 reg_process_hint+0x31e/0x8aa [cfg80211] reg_todo+0x204/0x5b9 [cfg80211] process_one_work+0x55f/0x8d0 worker_thread+0x5dd/0x841 kthread+0x270/0x285 ret_from_fork+0x22/0x40 <snipped>
Signed-off-by: Yu Zhao yuzhao@google.com Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/wireless/reg.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/net/wireless/reg.c b/net/wireless/reg.c index 765dedb12361..24cfa2776f50 100644 --- a/net/wireless/reg.c +++ b/net/wireless/reg.c @@ -2661,11 +2661,12 @@ static void reg_process_hint(struct regulatory_request *reg_request) { struct wiphy *wiphy = NULL; enum reg_request_treatment treatment; + enum nl80211_reg_initiator initiator = reg_request->initiator;
if (reg_request->wiphy_idx != WIPHY_IDX_INVALID) wiphy = wiphy_idx_to_wiphy(reg_request->wiphy_idx);
- switch (reg_request->initiator) { + switch (initiator) { case NL80211_REGDOM_SET_BY_CORE: treatment = reg_process_hint_core(reg_request); break; @@ -2683,7 +2684,7 @@ static void reg_process_hint(struct regulatory_request *reg_request) treatment = reg_process_hint_country_ie(wiphy, reg_request); break; default: - WARN(1, "invalid initiator %d\n", reg_request->initiator); + WARN(1, "invalid initiator %d\n", initiator); goto out_free; }
@@ -2698,7 +2699,7 @@ static void reg_process_hint(struct regulatory_request *reg_request) */ if (treatment == REG_REQ_ALREADY_SET && wiphy && wiphy->regulatory_flags & REGULATORY_STRICT_REG) { - wiphy_update_regulatory(wiphy, reg_request->initiator); + wiphy_update_regulatory(wiphy, initiator); wiphy_all_share_dfs_chan_state(wiphy); reg_check_channels(); }