[PATCH v5.10.277] wifi: mac80211: Avoid address calculations via out of bounds array indexing

[PATCH v5.10.277] wifi: mac80211: Avoid address calculations via out of bounds array indexing

[Hardik Gohil]

From: Kenton Groombridge <concord@gentoo.org>

[ 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@chromium.org>
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Kenton Groombridge <concord@gentoo.org>
Link: https://msgid.link/20240605152218.236061-1-concord@gentoo.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
[Xiangyu: Modified to apply on 6.1.y and 6.6.y]
Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Hardik Gohil <hgohil@mvista.com>
---
 net/mac80211/scan.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index be5d02c..bcbbb9f 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -351,7 +351,8 @@ 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,
@@ -361,34 +362,34 @@ 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, req->scan_width);
 
 	if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
-- 
2.7.4

Re: [PATCH v5.10.277] wifi: mac80211: Avoid address calculations via out of bounds array indexing

[Greg KH]

On Sat, Oct 19, 2024 at 11:06:40AM +0530, Hardik Gohil wrote:
> From: Kenton Groombridge <concord@gentoo.org>
> 
> [ Upstream commit 2663d0462eb32ae7c9b035300ab6b1523886c718 ]

We can't take patches for 5.10 that are not already in 5.15.  Please fix
up and resend for ALL relevent trees.

thanks,

greg k-h

Re: [PATCH v5.10.277] wifi: mac80211: Avoid address calculations via out of bounds array indexing

[Hardik Gohil]

On Mon, Oct 21, 2024 at 3:10 PM Greg KH <gregkh@linuxfoundation.org> wrote:
>
> On Sat, Oct 19, 2024 at 11:06:40AM +0530, Hardik Gohil wrote:
> > From: Kenton Groombridge <concord@gentoo.org>
> >
> > [ Upstream commit 2663d0462eb32ae7c9b035300ab6b1523886c718 ]
>
> We can't take patches for 5.10 that are not already in 5.15.  Please fix
> up and resend for ALL relevent trees.
>
> thanks,
>
> greg k-h

I have just confirmed those are applicable to v5.15 and v5.10.

Request to add those patches.

Re: [PATCH v5.10.277] wifi: mac80211: Avoid address calculations via out of bounds array indexing

[Greg KH]

On Mon, Oct 28, 2024 at 05:00:02PM +0530, Hardik Gohil wrote:
> On Mon, Oct 21, 2024 at 3:10 PM Greg KH <gregkh@linuxfoundation.org> wrote:
> >
> > On Sat, Oct 19, 2024 at 11:06:40AM +0530, Hardik Gohil wrote:
> > > From: Kenton Groombridge <concord@gentoo.org>
> > >
> > > [ Upstream commit 2663d0462eb32ae7c9b035300ab6b1523886c718 ]
> >
> > We can't take patches for 5.10 that are not already in 5.15.  Please fix
> > up and resend for ALL relevent trees.
> >
> > thanks,
> >
> > greg k-h
> 
> I have just confirmed those are applicable to v5.15 and v5.10.
> 
> Request to add those patches.

Please send tested backports.

thanks,

greg k-h

Re: [PATCH v5.10.y v5.4.y] wifi: mac80211: Avoid address calculations via out of bounds array indexing

[Hardik Gohil]

From: Kenton Groombridge <concord@gentoo.org>

[ 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@chromium.org>
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Kenton Groombridge <concord@gentoo.org>
Link: https://msgid.link/20240605152218.236061-1-concord@gentoo.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
[Xiangyu: Modified to apply on 6.1.y and 6.6.y]
Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Hardik Gohil <hgohil@mvista.com>
---
 net/mac80211/scan.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index be5d02c..bcbbb9f 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -351,7 +351,8 @@ 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,
@@ -361,34 +362,34 @@ 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, req->scan_width);

  if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
-- 
2.7.4

Re: [PATCH v5.10.y v5.4.y] wifi: mac80211: Avoid address calculations via out of bounds array indexing

[Greg KH]

On Thu, Dec 05, 2024 at 11:41:45AM +0530, Hardik Gohil wrote:
> From: Kenton Groombridge <concord@gentoo.org>
> 
> [ 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@chromium.org>
> Signed-off-by: Kees Cook <kees@kernel.org>
> Signed-off-by: Kenton Groombridge <concord@gentoo.org>
> Link: https://msgid.link/20240605152218.236061-1-concord@gentoo.org
> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
> [Xiangyu: Modified to apply on 6.1.y and 6.6.y]
> Signed-off-by: Xiangyu Chen <xiangyu.chen@windriver.com>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> Signed-off-by: Hardik Gohil <hgohil@mvista.com>

What did you do to change this patch?

Also, what about 5.15.y, you can't "skip" a stable tree :(

thanks,

greg k-h

Re: [PATCH v5.10.y v5.4.y] wifi: mac80211: Avoid address calculations via out of bounds array indexing

[Hardik Gohil]

>
> What did you do to change this patch?
>
> Also, what about 5.15.y, you can't "skip" a stable tree :(
>
> thanks,
>
> greg k-h

I have not done any changes to patch but tested the patch from 6.6.y
by applying to 5.10.y and 5.4.y versions

ref:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v6.6.65&id=26b177ecdd311f20de4c379f0630858a675dfc0c

Re: [PATCH v5.10.y v5.4.y] wifi: mac80211: Avoid address calculations via out of bounds array indexing

[Greg KH]

On Fri, Dec 13, 2024 at 03:54:58PM +0530, Hardik Gohil wrote:
> >
> > What did you do to change this patch?
> >
> > Also, what about 5.15.y, you can't "skip" a stable tree :(
> >
> > thanks,
> >
> > greg k-h
> 
> I have not done any changes to patch but tested the patch from 6.6.y
> by applying to 5.10.y and 5.4.y versions
> 
> ref:
> https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v6.6.65&id=26b177ecdd311f20de4c379f0630858a675dfc0c

I have no context here at all, sorry :(