This is a note to let you know that I've just added the patch titled
wifi: mac80211: Avoid address calculations via out of bounds array indexing
to the 6.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
wifi-mac80211-avoid-address-calculations-via-out-of-.patch
and it can be found in the queue-6.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 07b79c7282a6a03a649f8111e1103ab0ef68e775
Author: Kenton Groombridge <concord@xxxxxxxxxx>
Date: Wed Jun 5 11:22:18 2024 -0400
wifi: mac80211: Avoid address calculations via out of bounds array indexing
[ Upstream commit 2663d0462eb32ae7c9b035300ab6b1523886c718 ]
req->n_channels must be set before req->channels[] can be used.
This patch fixes one of the issues encountered in [1].
[ 83.964255] UBSAN: array-index-out-of-bounds in net/mac80211/scan.c:364:4
[ 83.964258] index 0 is out of range for type 'struct ieee80211_channel *[]'
[...]
[ 83.964264] Call Trace:
[ 83.964267] <TASK>
[ 83.964269] dump_stack_lvl+0x3f/0xc0
[ 83.964274] __ubsan_handle_out_of_bounds+0xec/0x110
[ 83.964278] ieee80211_prep_hw_scan+0x2db/0x4b0
[ 83.964281] __ieee80211_start_scan+0x601/0x990
[ 83.964291] nl80211_trigger_scan+0x874/0x980
[ 83.964295] genl_family_rcv_msg_doit+0xe8/0x160
[ 83.964298] genl_rcv_msg+0x240/0x270
[...]
[1] https://bugzilla.kernel.org/show_bug.cgi?id=218810
Co-authored-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Kees Cook <kees@xxxxxxxxxx>
Signed-off-by: Kenton Groombridge <concord@xxxxxxxxxx>
Link: https://msgid.link/20240605152218.236061-1-concord@xxxxxxxxxx
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 8ecc4b710b0e6..b5f2df61c7f67 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -358,7 +358,8 @@ static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata)
struct cfg80211_scan_request *req;
struct cfg80211_chan_def chandef;
u8 bands_used = 0;
- int i, ielen, n_chans;
+ int i, ielen;
+ u32 *n_chans;
u32 flags = 0;
req = rcu_dereference_protected(local->scan_req,
@@ -368,34 +369,34 @@ static bool ieee80211_prep_hw_scan(struct ieee80211_sub_if_data *sdata)
return false;
if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
+ local->hw_scan_req->req.n_channels = req->n_channels;
+
for (i = 0; i < req->n_channels; i++) {
local->hw_scan_req->req.channels[i] = req->channels[i];
bands_used |= BIT(req->channels[i]->band);
}
-
- n_chans = req->n_channels;
} else {
do {
if (local->hw_scan_band == NUM_NL80211_BANDS)
return false;
- n_chans = 0;
+ n_chans = &local->hw_scan_req->req.n_channels;
+ *n_chans = 0;
for (i = 0; i < req->n_channels; i++) {
if (req->channels[i]->band !=
local->hw_scan_band)
continue;
- local->hw_scan_req->req.channels[n_chans] =
+ local->hw_scan_req->req.channels[(*n_chans)++] =
req->channels[i];
- n_chans++;
+
bands_used |= BIT(req->channels[i]->band);
}
local->hw_scan_band++;
- } while (!n_chans);
+ } while (!*n_chans);
}
- local->hw_scan_req->req.n_channels = n_chans;
ieee80211_prepare_scan_chandef(&chandef);
if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
