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[PATCH v2] Bluetooth: hci: fix null-ptr-deref in hci_read_supported_codecs

Sungwoo Kim posted 1 patch 1 year, 7 months ago
There is a newer version of this series
net/bluetooth/hci_sync.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)
[PATCH v2] Bluetooth: hci: fix null-ptr-deref in hci_read_supported_codecs
Posted by Sungwoo Kim 1 year, 7 months ago 
__hci_cmd_sync_sk() returns NULL if a command returns a status event
as there are no parameters.
Fix __hci_cmd_sync_sk() to not return NULL.

KASAN: null-ptr-deref in range [0x0000000000000070-0x0000000000000077]
CPU: 1 PID: 2000 Comm: kworker/u9:5 Not tainted 6.9.0-ga6bcb805883c-dirty #10
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Workqueue: hci7 hci_power_on
RIP: 0010:hci_read_supported_codecs+0xb9/0x870 net/bluetooth/hci_codec.c:138
Code: 08 48 89 ef e8 b8 c1 8f fd 48 8b 75 00 e9 96 00 00 00 49 89 c6 48 ba 00 00 00 00 00 fc ff df 4c 8d 60 70 4c 89 e3 48 c1 eb 03 <0f> b6 04 13 84 c0 0f 85 82 06 00 00 41 83 3c 24 02 77 0a e8 bf 78
RSP: 0018:ffff888120bafac8 EFLAGS: 00010212
RAX: 0000000000000000 RBX: 000000000000000e RCX: ffff8881173f0040
RDX: dffffc0000000000 RSI: ffffffffa58496c0 RDI: ffff88810b9ad1e4
RBP: ffff88810b9ac000 R08: ffffffffa77882a7 R09: 1ffffffff4ef1054
R10: dffffc0000000000 R11: fffffbfff4ef1055 R12: 0000000000000070
R13: 0000000000000000 R14: 0000000000000000 R15: ffff88810b9ac000
FS:  0000000000000000(0000) GS:ffff8881f6c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6ddaa3439e CR3: 0000000139764003 CR4: 0000000000770ef0
PKRU: 55555554
Call Trace:
 <TASK>
 hci_read_local_codecs_sync net/bluetooth/hci_sync.c:4546 [inline]
 hci_init_stage_sync net/bluetooth/hci_sync.c:3441 [inline]
 hci_init4_sync net/bluetooth/hci_sync.c:4706 [inline]
 hci_init_sync net/bluetooth/hci_sync.c:4742 [inline]
 hci_dev_init_sync net/bluetooth/hci_sync.c:4912 [inline]
 hci_dev_open_sync+0x19a9/0x2d30 net/bluetooth/hci_sync.c:4994
 hci_dev_do_open net/bluetooth/hci_core.c:483 [inline]
 hci_power_on+0x11e/0x560 net/bluetooth/hci_core.c:1015
 process_one_work kernel/workqueue.c:3267 [inline]
 process_scheduled_works+0x8ef/0x14f0 kernel/workqueue.c:3348
 worker_thread+0x91f/0xe50 kernel/workqueue.c:3429
 kthread+0x2cb/0x360 kernel/kthread.c:388
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Fixes: abfeea476c68 ("Bluetooth: hci_sync: Convert MGMT_OP_START_DISCOVERY")

Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
---
v1 -> v2: make __hci_cmd_sync_sk() not return NULL

 net/bluetooth/hci_sync.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index 76b283b8e..c4e4abc6e 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -201,6 +201,12 @@ struct sk_buff *__hci_cmd_sync_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
 		return ERR_PTR(err);
 	}
 
+	/* If command return a status event skb will be set to NULL as there are
+	 * no parameters.
+	 */
+	if (!skb)
+		return ERR_PTR(-ENODATA);
+
 	return skb;
 }
 EXPORT_SYMBOL(__hci_cmd_sync_sk);
@@ -250,6 +256,11 @@ int __hci_cmd_sync_status_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
 	u8 status;
 
 	skb = __hci_cmd_sync_sk(hdev, opcode, plen, param, event, timeout, sk);
+
+	/* If command return a status event, skb will be set to -ENODATA */
+	if (skb == ERR_PTR(-ENODATA))
+		return 0;
+
 	if (IS_ERR(skb)) {
 		if (!event)
 			bt_dev_err(hdev, "Opcode 0x%4.4x failed: %ld", opcode,
@@ -257,13 +268,6 @@ int __hci_cmd_sync_status_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
 		return PTR_ERR(skb);
 	}
 
-	/* If command return a status event skb will be set to NULL as there are
-	 * no parameters, in case of failure IS_ERR(skb) would have be set to
-	 * the actual error would be found with PTR_ERR(skb).
-	 */
-	if (!skb)
-		return 0;
-
 	status = skb->data[0];
 
 	kfree_skb(skb);
-- 
2.34.1
Re: [PATCH v2] Bluetooth: hci: fix null-ptr-deref in hci_read_supported_codecs
Posted by Sungwoo Kim 1 year, 3 months ago 
Dear Luiz, could you review this? This bug and fix are still valid but
have been forgotten for some reason.

On Sat, Jul 6, 2024 at 6:53 PM Sungwoo Kim <iam@sung-woo.kim> wrote:
>
> __hci_cmd_sync_sk() returns NULL if a command returns a status event
> as there are no parameters.
> Fix __hci_cmd_sync_sk() to not return NULL.
>
> KASAN: null-ptr-deref in range [0x0000000000000070-0x0000000000000077]
> CPU: 1 PID: 2000 Comm: kworker/u9:5 Not tainted 6.9.0-ga6bcb805883c-dirty #10
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
> Workqueue: hci7 hci_power_on
> RIP: 0010:hci_read_supported_codecs+0xb9/0x870 net/bluetooth/hci_codec.c:138
> Code: 08 48 89 ef e8 b8 c1 8f fd 48 8b 75 00 e9 96 00 00 00 49 89 c6 48 ba 00 00 00 00 00 fc ff df 4c 8d 60 70 4c 89 e3 48 c1 eb 03 <0f> b6 04 13 84 c0 0f 85 82 06 00 00 41 83 3c 24 02 77 0a e8 bf 78
> RSP: 0018:ffff888120bafac8 EFLAGS: 00010212
> RAX: 0000000000000000 RBX: 000000000000000e RCX: ffff8881173f0040
> RDX: dffffc0000000000 RSI: ffffffffa58496c0 RDI: ffff88810b9ad1e4
> RBP: ffff88810b9ac000 R08: ffffffffa77882a7 R09: 1ffffffff4ef1054
> R10: dffffc0000000000 R11: fffffbfff4ef1055 R12: 0000000000000070
> R13: 0000000000000000 R14: 0000000000000000 R15: ffff88810b9ac000
> FS:  0000000000000000(0000) GS:ffff8881f6c00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f6ddaa3439e CR3: 0000000139764003 CR4: 0000000000770ef0
> PKRU: 55555554
> Call Trace:
>  <TASK>
>  hci_read_local_codecs_sync net/bluetooth/hci_sync.c:4546 [inline]
>  hci_init_stage_sync net/bluetooth/hci_sync.c:3441 [inline]
>  hci_init4_sync net/bluetooth/hci_sync.c:4706 [inline]
>  hci_init_sync net/bluetooth/hci_sync.c:4742 [inline]
>  hci_dev_init_sync net/bluetooth/hci_sync.c:4912 [inline]
>  hci_dev_open_sync+0x19a9/0x2d30 net/bluetooth/hci_sync.c:4994
>  hci_dev_do_open net/bluetooth/hci_core.c:483 [inline]
>  hci_power_on+0x11e/0x560 net/bluetooth/hci_core.c:1015
>  process_one_work kernel/workqueue.c:3267 [inline]
>  process_scheduled_works+0x8ef/0x14f0 kernel/workqueue.c:3348
>  worker_thread+0x91f/0xe50 kernel/workqueue.c:3429
>  kthread+0x2cb/0x360 kernel/kthread.c:388
>  ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
>  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
>
> Fixes: abfeea476c68 ("Bluetooth: hci_sync: Convert MGMT_OP_START_DISCOVERY")
>
> Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
> ---
> v1 -> v2: make __hci_cmd_sync_sk() not return NULL
>
>  net/bluetooth/hci_sync.c | 18 +++++++++++-------
>  1 file changed, 11 insertions(+), 7 deletions(-)
>
> diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
> index 76b283b8e..c4e4abc6e 100644
> --- a/net/bluetooth/hci_sync.c
> +++ b/net/bluetooth/hci_sync.c
> @@ -201,6 +201,12 @@ struct sk_buff *__hci_cmd_sync_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
>                 return ERR_PTR(err);
>         }
>
> +       /* If command return a status event skb will be set to NULL as there are
> +        * no parameters.
> +        */
> +       if (!skb)
> +               return ERR_PTR(-ENODATA);
> +
>         return skb;
>  }
>  EXPORT_SYMBOL(__hci_cmd_sync_sk);
> @@ -250,6 +256,11 @@ int __hci_cmd_sync_status_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
>         u8 status;
>
>         skb = __hci_cmd_sync_sk(hdev, opcode, plen, param, event, timeout, sk);
> +
> +       /* If command return a status event, skb will be set to -ENODATA */
> +       if (skb == ERR_PTR(-ENODATA))
> +               return 0;
> +
>         if (IS_ERR(skb)) {
>                 if (!event)
>                         bt_dev_err(hdev, "Opcode 0x%4.4x failed: %ld", opcode,
> @@ -257,13 +268,6 @@ int __hci_cmd_sync_status_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
>                 return PTR_ERR(skb);
>         }
>
> -       /* If command return a status event skb will be set to NULL as there are
> -        * no parameters, in case of failure IS_ERR(skb) would have be set to
> -        * the actual error would be found with PTR_ERR(skb).
> -        */
> -       if (!skb)
> -               return 0;
> -
>         status = skb->data[0];
>
>         kfree_skb(skb);
> --
> 2.34.1
>
Re: [PATCH v2] Bluetooth: hci: fix null-ptr-deref in hci_read_supported_codecs
Posted by Luiz Augusto von Dentz 1 year, 3 months ago 
Hi Sungwoo,

On Mon, Oct 28, 2024 at 10:41 PM Sungwoo Kim <iam@sung-woo.kim> wrote:
>
> Dear Luiz, could you review this? This bug and fix are still valid but
> have been forgotten for some reason.

Please resend.

> On Sat, Jul 6, 2024 at 6:53 PM Sungwoo Kim <iam@sung-woo.kim> wrote:
> >
> > __hci_cmd_sync_sk() returns NULL if a command returns a status event
> > as there are no parameters.
> > Fix __hci_cmd_sync_sk() to not return NULL.
> >
> > KASAN: null-ptr-deref in range [0x0000000000000070-0x0000000000000077]
> > CPU: 1 PID: 2000 Comm: kworker/u9:5 Not tainted 6.9.0-ga6bcb805883c-dirty #10
> > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
> > Workqueue: hci7 hci_power_on
> > RIP: 0010:hci_read_supported_codecs+0xb9/0x870 net/bluetooth/hci_codec.c:138
> > Code: 08 48 89 ef e8 b8 c1 8f fd 48 8b 75 00 e9 96 00 00 00 49 89 c6 48 ba 00 00 00 00 00 fc ff df 4c 8d 60 70 4c 89 e3 48 c1 eb 03 <0f> b6 04 13 84 c0 0f 85 82 06 00 00 41 83 3c 24 02 77 0a e8 bf 78
> > RSP: 0018:ffff888120bafac8 EFLAGS: 00010212
> > RAX: 0000000000000000 RBX: 000000000000000e RCX: ffff8881173f0040
> > RDX: dffffc0000000000 RSI: ffffffffa58496c0 RDI: ffff88810b9ad1e4
> > RBP: ffff88810b9ac000 R08: ffffffffa77882a7 R09: 1ffffffff4ef1054
> > R10: dffffc0000000000 R11: fffffbfff4ef1055 R12: 0000000000000070
> > R13: 0000000000000000 R14: 0000000000000000 R15: ffff88810b9ac000
> > FS:  0000000000000000(0000) GS:ffff8881f6c00000(0000) knlGS:0000000000000000
> > CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > CR2: 00007f6ddaa3439e CR3: 0000000139764003 CR4: 0000000000770ef0
> > PKRU: 55555554
> > Call Trace:
> >  <TASK>
> >  hci_read_local_codecs_sync net/bluetooth/hci_sync.c:4546 [inline]
> >  hci_init_stage_sync net/bluetooth/hci_sync.c:3441 [inline]
> >  hci_init4_sync net/bluetooth/hci_sync.c:4706 [inline]
> >  hci_init_sync net/bluetooth/hci_sync.c:4742 [inline]
> >  hci_dev_init_sync net/bluetooth/hci_sync.c:4912 [inline]
> >  hci_dev_open_sync+0x19a9/0x2d30 net/bluetooth/hci_sync.c:4994
> >  hci_dev_do_open net/bluetooth/hci_core.c:483 [inline]
> >  hci_power_on+0x11e/0x560 net/bluetooth/hci_core.c:1015
> >  process_one_work kernel/workqueue.c:3267 [inline]
> >  process_scheduled_works+0x8ef/0x14f0 kernel/workqueue.c:3348
> >  worker_thread+0x91f/0xe50 kernel/workqueue.c:3429
> >  kthread+0x2cb/0x360 kernel/kthread.c:388
> >  ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
> >  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
> >
> > Fixes: abfeea476c68 ("Bluetooth: hci_sync: Convert MGMT_OP_START_DISCOVERY")
> >
> > Signed-off-by: Sungwoo Kim <iam@sung-woo.kim>
> > ---
> > v1 -> v2: make __hci_cmd_sync_sk() not return NULL
> >
> >  net/bluetooth/hci_sync.c | 18 +++++++++++-------
> >  1 file changed, 11 insertions(+), 7 deletions(-)
> >
> > diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
> > index 76b283b8e..c4e4abc6e 100644
> > --- a/net/bluetooth/hci_sync.c
> > +++ b/net/bluetooth/hci_sync.c
> > @@ -201,6 +201,12 @@ struct sk_buff *__hci_cmd_sync_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
> >                 return ERR_PTR(err);
> >         }
> >
> > +       /* If command return a status event skb will be set to NULL as there are
> > +        * no parameters.
> > +        */
> > +       if (!skb)
> > +               return ERR_PTR(-ENODATA);
> > +
> >         return skb;
> >  }
> >  EXPORT_SYMBOL(__hci_cmd_sync_sk);
> > @@ -250,6 +256,11 @@ int __hci_cmd_sync_status_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
> >         u8 status;
> >
> >         skb = __hci_cmd_sync_sk(hdev, opcode, plen, param, event, timeout, sk);
> > +
> > +       /* If command return a status event, skb will be set to -ENODATA */
> > +       if (skb == ERR_PTR(-ENODATA))
> > +               return 0;
> > +
> >         if (IS_ERR(skb)) {
> >                 if (!event)
> >                         bt_dev_err(hdev, "Opcode 0x%4.4x failed: %ld", opcode,
> > @@ -257,13 +268,6 @@ int __hci_cmd_sync_status_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
> >                 return PTR_ERR(skb);
> >         }
> >
> > -       /* If command return a status event skb will be set to NULL as there are
> > -        * no parameters, in case of failure IS_ERR(skb) would have be set to
> > -        * the actual error would be found with PTR_ERR(skb).
> > -        */
> > -       if (!skb)
> > -               return 0;
> > -
> >         status = skb->data[0];
> >
> >         kfree_skb(skb);
> > --
> > 2.34.1
> >



-- 
Luiz Augusto von Dentz
Re: [PATCH v2] Bluetooth: hci: fix null-ptr-deref in hci_read_supported_codecs
Posted by Markus Elfring 1 year, 7 months ago 
Please put email addresses for recipients not only into the message field “Cc”.


…
> Fix __hci_cmd_sync_sk() to not return NULL.
>
> KASAN: null-ptr-deref in range [0x0000000000000070-0x0000000000000077]
…

How do you think about to use a summary phrase like
“Prevent null pointer dereference in hci_read_supported_codecs()”?


…
> Fixes: abfeea476c68 ("Bluetooth: hci_sync: Convert MGMT_OP_START_DISCOVERY")
…

Would you like to add a “stable tag” accordingly?
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/stable-kernel-rules.rst?h=v6.10-rc6#n34

Regards,
Markus

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