From: Matias Karhumaa matias.karhumaa@gmail.com
[ Upstream commit 30d65e0804d58a03d1a8ea4e12c6fc07ed08218b ]
Fix crash caused by NULL pointer dereference when debugfs functions le_max_key_read, le_max_key_size_write, le_min_key_size_read or le_min_key_size_write and Bluetooth adapter was powered off.
Fix is to move max_key_size and min_key_size from smp_dev to hci_dev. At the same time they were renamed to le_max_key_size and le_min_key_size.
BUG: unable to handle kernel NULL pointer dereference at 00000000000002e8 PGD 0 P4D 0 Oops: 0000 [#24] SMP PTI CPU: 2 PID: 6255 Comm: cat Tainted: G D OE 4.18.9-200.fc28.x86_64 #1 Hardware name: LENOVO 4286CTO/4286CTO, BIOS 8DET76WW (1.46 ) 06/21/2018 RIP: 0010:le_max_key_size_read+0x45/0xb0 [bluetooth] Code: 00 00 00 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 31 c0 48 8b 87 c8 00 00 00 48 8d 7c 24 04 48 8b 80 48 0a 00 00 <48> 8b 80 e8 02 00 00 0f b6 48 52 e8 fb b6 b3 ed be 04 00 00 00 48 RSP: 0018:ffffab23c3ff3df0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 00007f0b4ca2e000 RCX: ffffab23c3ff3f08 RDX: ffffffffc0ddb033 RSI: 0000000000000004 RDI: ffffab23c3ff3df4 RBP: 0000000000020000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffab23c3ff3ed8 R11: 0000000000000000 R12: ffffab23c3ff3f08 R13: 00007f0b4ca2e000 R14: 0000000000020000 R15: ffffab23c3ff3f08 FS: 00007f0b4ca0f540(0000) GS:ffff91bd5e280000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000002e8 CR3: 00000000629fa006 CR4: 00000000000606e0 Call Trace: full_proxy_read+0x53/0x80 __vfs_read+0x36/0x180 vfs_read+0x8a/0x140 ksys_read+0x4f/0xb0 do_syscall_64+0x5b/0x160 entry_SYSCALL_64_after_hwframe+0x44/0xa9
Signed-off-by: Matias Karhumaa matias.karhumaa@gmail.com Signed-off-by: Marcel Holtmann marcel@holtmann.org Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/bluetooth/hci_core.h | 2 ++ net/bluetooth/hci_core.c | 2 ++ net/bluetooth/smp.c | 23 +++++++++-------------- 3 files changed, 13 insertions(+), 14 deletions(-)
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h index 0db1b9b428b7..1dfb75057580 100644 --- a/include/net/bluetooth/hci_core.h +++ b/include/net/bluetooth/hci_core.h @@ -259,6 +259,8 @@ struct hci_dev { __u16 le_max_tx_time; __u16 le_max_rx_len; __u16 le_max_rx_time; + __u8 le_max_key_size; + __u8 le_min_key_size; __u16 discov_interleaved_timeout; __u16 conn_info_min_age; __u16 conn_info_max_age; diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index 74b29c7d841c..a06f03047717 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -3084,6 +3084,8 @@ struct hci_dev *hci_alloc_dev(void) hdev->le_max_tx_time = 0x0148; hdev->le_max_rx_len = 0x001b; hdev->le_max_rx_time = 0x0148; + hdev->le_max_key_size = SMP_MAX_ENC_KEY_SIZE; + hdev->le_min_key_size = SMP_MIN_ENC_KEY_SIZE; hdev->le_tx_def_phys = HCI_LE_SET_PHY_1M; hdev->le_rx_def_phys = HCI_LE_SET_PHY_1M;
diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c index 73f7211d0431..a1c1b7e8a45c 100644 --- a/net/bluetooth/smp.c +++ b/net/bluetooth/smp.c @@ -88,9 +88,6 @@ struct smp_dev { u8 local_rand[16]; bool debug_key;
- u8 min_key_size; - u8 max_key_size; - struct crypto_cipher *tfm_aes; struct crypto_shash *tfm_cmac; struct crypto_kpp *tfm_ecdh; @@ -720,7 +717,7 @@ static void build_pairing_cmd(struct l2cap_conn *conn, if (rsp == NULL) { req->io_capability = conn->hcon->io_capability; req->oob_flag = oob_flag; - req->max_key_size = SMP_DEV(hdev)->max_key_size; + req->max_key_size = hdev->le_max_key_size; req->init_key_dist = local_dist; req->resp_key_dist = remote_dist; req->auth_req = (authreq & AUTH_REQ_MASK(hdev)); @@ -731,7 +728,7 @@ static void build_pairing_cmd(struct l2cap_conn *conn,
rsp->io_capability = conn->hcon->io_capability; rsp->oob_flag = oob_flag; - rsp->max_key_size = SMP_DEV(hdev)->max_key_size; + rsp->max_key_size = hdev->le_max_key_size; rsp->init_key_dist = req->init_key_dist & remote_dist; rsp->resp_key_dist = req->resp_key_dist & local_dist; rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev)); @@ -745,7 +742,7 @@ static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) struct hci_dev *hdev = conn->hcon->hdev; struct smp_chan *smp = chan->data;
- if (max_key_size > SMP_DEV(hdev)->max_key_size || + if (max_key_size > hdev->le_max_key_size || max_key_size < SMP_MIN_ENC_KEY_SIZE) return SMP_ENC_KEY_SIZE;
@@ -3264,8 +3261,6 @@ static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) smp->tfm_aes = tfm_aes; smp->tfm_cmac = tfm_cmac; smp->tfm_ecdh = tfm_ecdh; - smp->min_key_size = SMP_MIN_ENC_KEY_SIZE; - smp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
create_chan: chan = l2cap_chan_create(); @@ -3391,7 +3386,7 @@ static ssize_t le_min_key_size_read(struct file *file, struct hci_dev *hdev = file->private_data; char buf[4];
- snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->min_key_size); + snprintf(buf, sizeof(buf), "%2u\n", hdev->le_min_key_size);
return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf)); } @@ -3412,11 +3407,11 @@ static ssize_t le_min_key_size_write(struct file *file,
sscanf(buf, "%hhu", &key_size);
- if (key_size > SMP_DEV(hdev)->max_key_size || + if (key_size > hdev->le_max_key_size || key_size < SMP_MIN_ENC_KEY_SIZE) return -EINVAL;
- SMP_DEV(hdev)->min_key_size = key_size; + hdev->le_min_key_size = key_size;
return count; } @@ -3435,7 +3430,7 @@ static ssize_t le_max_key_size_read(struct file *file, struct hci_dev *hdev = file->private_data; char buf[4];
- snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->max_key_size); + snprintf(buf, sizeof(buf), "%2u\n", hdev->le_max_key_size);
return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf)); } @@ -3457,10 +3452,10 @@ static ssize_t le_max_key_size_write(struct file *file, sscanf(buf, "%hhu", &key_size);
if (key_size > SMP_MAX_ENC_KEY_SIZE || - key_size < SMP_DEV(hdev)->min_key_size) + key_size < hdev->le_min_key_size) return -EINVAL;
- SMP_DEV(hdev)->max_key_size = key_size; + hdev->le_max_key_size = key_size;
return count; }