[ Upstream commit 857282b819cbaa0675aaab1e7542e2c0579f52d7 ]
This patch fixes a NULL pointer dereference bug in brcmfmac that occurs
when a high 'sd_sgentry_align' value applies (e.g. 512) and a lot of queued SKBs
are sent from the pkt queue.
The problem is the number of entries in the pre-allocated sgtable, it is
nents = max(rxglom_size, txglom_size) + max(rxglom_size, txglom_size) >> 4 + 1.
Given the default [rt]xglom_size=32 it's actually 35 which is too small.
Worst case, the pkt queue can end up with 64 SKBs. This occurs when a new SKB
is added for each original SKB if tailroom isn't enough to hold tail_pad.
At least one sg entry is needed for each SKB. So, eventually the "skb_queue_walk loop"
in brcmf_sdiod_sglist_rw may run out of sg entries. This makes sg_next return
NULL and this causes the oops.
The patch sets nents to max(rxglom_size, txglom_size) * 2 to be able handle
the worst-case.
Btw. this requires only 64-35=29 * 16 (or 20 if CONFIG_NEED_SG_DMA_LENGTH) = 464
additional bytes of memory.
Signed-off-by: Norbert van Bolhuis <nvbolhuis@gmail.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://patch.msgid.link/20241107132903.13513-1-nvbolhuis@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0f7352557a35ab7888bc7831411ec8a3cbe20d78 ]
This is the candidate patch of CVE-2023-47233 :
https://nvd.nist.gov/vuln/detail/CVE-2023-47233
In brcm80211 driver,it starts with the following invoking chain
to start init a timeout worker:
->brcmf_usb_probe
->brcmf_usb_probe_cb
->brcmf_attach
->brcmf_bus_started
->brcmf_cfg80211_attach
->wl_init_priv
->brcmf_init_escan
->INIT_WORK(&cfg->escan_timeout_work,
brcmf_cfg80211_escan_timeout_worker);
If we disconnect the USB by hotplug, it will call
brcmf_usb_disconnect to make cleanup. The invoking chain is :
brcmf_usb_disconnect
->brcmf_usb_disconnect_cb
->brcmf_detach
->brcmf_cfg80211_detach
->kfree(cfg);
While the timeout woker may still be running. This will cause
a use-after-free bug on cfg in brcmf_cfg80211_escan_timeout_worker.
Fix it by deleting the timer and canceling the worker in
brcmf_cfg80211_detach.
Fixes: e756af5b30b0 ("brcmfmac: add e-scan support.")
Signed-off-by: Zheng Wang <zyytlz.wz@163.com>
Cc: stable@vger.kernel.org
[arend.vanspriel@broadcom.com: keep timer delete as is and cancel work just before free]
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240107072504.392713-1-arend.vanspriel@broadcom.com
Signed-off-by: Sasha Levin <sashal@kernel.org>