2012-06-26 11:26:47

by Samuel Ortiz

[permalink] [raw]
Subject: [PATCH 0/2] NFC fixes for 3.5

Hi John,

I have a couple of 3.5 fixes for NFC, one of them being a security issue.
As usual you can apply them manually or pull from:

git://git.kernel.org/pub/scm/linux/kernel/git/sameo/nfc-3.0.git for-wireless

Dan Rosenberg (1):
NFC: Prevent multiple buffer overflows in NCI

Eric Dumazet (1):
NFC: Return from rawsock_release when sk is NULL

net/nfc/nci/ntf.c | 10 +++++-----
net/nfc/rawsock.c | 5 ++++-
2 files changed, 9 insertions(+), 6 deletions(-)

--
1.7.10



2012-06-26 11:26:57

by Samuel Ortiz

[permalink] [raw]
Subject: [PATCH 1/2] NFC: Prevent multiple buffer overflows in NCI

From: Dan Rosenberg <[email protected]>

Fix multiple remotely-exploitable stack-based buffer overflows due to
the NCI code pulling length fields directly from incoming frames and
copying too much data into statically-sized arrays.

Signed-off-by: Dan Rosenberg <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: Lauro Ramos Venancio <[email protected]>
Cc: Aloisio Almeida Jr <[email protected]>
Cc: Samuel Ortiz <[email protected]>
Cc: David S. Miller <[email protected]>
Acked-by: Ilan Elias <[email protected]>
Signed-off-by: Samuel Ortiz <[email protected]>
---
net/nfc/nci/ntf.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/net/nfc/nci/ntf.c b/net/nfc/nci/ntf.c
index cb26461..2ab196a 100644
--- a/net/nfc/nci/ntf.c
+++ b/net/nfc/nci/ntf.c
@@ -106,7 +106,7 @@ static __u8 *nci_extract_rf_params_nfca_passive_poll(struct nci_dev *ndev,
nfca_poll->sens_res = __le16_to_cpu(*((__u16 *)data));
data += 2;

- nfca_poll->nfcid1_len = *data++;
+ nfca_poll->nfcid1_len = min_t(__u8, *data++, NFC_NFCID1_MAXSIZE);

pr_debug("sens_res 0x%x, nfcid1_len %d\n",
nfca_poll->sens_res, nfca_poll->nfcid1_len);
@@ -130,7 +130,7 @@ static __u8 *nci_extract_rf_params_nfcb_passive_poll(struct nci_dev *ndev,
struct rf_tech_specific_params_nfcb_poll *nfcb_poll,
__u8 *data)
{
- nfcb_poll->sensb_res_len = *data++;
+ nfcb_poll->sensb_res_len = min_t(__u8, *data++, NFC_SENSB_RES_MAXSIZE);

pr_debug("sensb_res_len %d\n", nfcb_poll->sensb_res_len);

@@ -145,7 +145,7 @@ static __u8 *nci_extract_rf_params_nfcf_passive_poll(struct nci_dev *ndev,
__u8 *data)
{
nfcf_poll->bit_rate = *data++;
- nfcf_poll->sensf_res_len = *data++;
+ nfcf_poll->sensf_res_len = min_t(__u8, *data++, NFC_SENSF_RES_MAXSIZE);

pr_debug("bit_rate %d, sensf_res_len %d\n",
nfcf_poll->bit_rate, nfcf_poll->sensf_res_len);
@@ -331,7 +331,7 @@ static int nci_extract_activation_params_iso_dep(struct nci_dev *ndev,
switch (ntf->activation_rf_tech_and_mode) {
case NCI_NFC_A_PASSIVE_POLL_MODE:
nfca_poll = &ntf->activation_params.nfca_poll_iso_dep;
- nfca_poll->rats_res_len = *data++;
+ nfca_poll->rats_res_len = min_t(__u8, *data++, 20);
pr_debug("rats_res_len %d\n", nfca_poll->rats_res_len);
if (nfca_poll->rats_res_len > 0) {
memcpy(nfca_poll->rats_res,
@@ -341,7 +341,7 @@ static int nci_extract_activation_params_iso_dep(struct nci_dev *ndev,

case NCI_NFC_B_PASSIVE_POLL_MODE:
nfcb_poll = &ntf->activation_params.nfcb_poll_iso_dep;
- nfcb_poll->attrib_res_len = *data++;
+ nfcb_poll->attrib_res_len = min_t(__u8, *data++, 50);
pr_debug("attrib_res_len %d\n", nfcb_poll->attrib_res_len);
if (nfcb_poll->attrib_res_len > 0) {
memcpy(nfcb_poll->attrib_res,
--
1.7.10


2012-06-26 11:27:03

by Samuel Ortiz

[permalink] [raw]
Subject: [PATCH 2/2] NFC: Return from rawsock_release when sk is NULL

From: Eric Dumazet <[email protected]>

Sasha Levin reported following panic :

[ 2136.383310] BUG: unable to handle kernel NULL pointer dereference at
00000000000003b0
[ 2136.384022] IP: [<ffffffff8114e400>] __lock_acquire+0xc0/0x4b0
[ 2136.384022] PGD 131c4067 PUD 11c0c067 PMD 0
[ 2136.388106] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[ 2136.388106] CPU 1
[ 2136.388106] Pid: 24855, comm: trinity-child1 Tainted: G W
3.5.0-rc2-sasha-00015-g7b268f7 #374
[ 2136.388106] RIP: 0010:[<ffffffff8114e400>] [<ffffffff8114e400>]
__lock_acquire+0xc0/0x4b0
[ 2136.388106] RSP: 0018:ffff8800130b3ca8 EFLAGS: 00010046
[ 2136.388106] RAX: 0000000000000086 RBX: ffff88001186b000 RCX:
0000000000000000
[ 2136.388106] RDX: 0000000000000000 RSI: 0000000000000000 RDI:
0000000000000000
[ 2136.388106] RBP: ffff8800130b3d08 R08: 0000000000000001 R09:
0000000000000000
[ 2136.388106] R10: 0000000000000000 R11: 0000000000000001 R12:
0000000000000002
[ 2136.388106] R13: 00000000000003b0 R14: 0000000000000000 R15:
0000000000000000
[ 2136.388106] FS: 00007fa5b1bd4700(0000) GS:ffff88001b800000(0000)
knlGS:0000000000000000
[ 2136.388106] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2136.388106] CR2: 00000000000003b0 CR3: 0000000011d1f000 CR4:
00000000000406e0
[ 2136.388106] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[ 2136.388106] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7:
0000000000000400
[ 2136.388106] Process trinity-child1 (pid: 24855, threadinfo
ffff8800130b2000, task ffff88001186b000)
[ 2136.388106] Stack:
[ 2136.388106] ffff8800130b3cd8 ffffffff81121785 ffffffff81236774
000080d000000001
[ 2136.388106] ffff88001b9d6c00 00000000001d6c00 ffffffff130b3d08
ffff88001186b000
[ 2136.388106] 0000000000000000 0000000000000002 0000000000000000
0000000000000000
[ 2136.388106] Call Trace:
[ 2136.388106] [<ffffffff81121785>] ? sched_clock_local+0x25/0x90
[ 2136.388106] [<ffffffff81236774>] ? get_empty_filp+0x74/0x220
[ 2136.388106] [<ffffffff8114e97a>] lock_acquire+0x18a/0x1e0
[ 2136.388106] [<ffffffff836b37df>] ? rawsock_release+0x4f/0xa0
[ 2136.388106] [<ffffffff837c0ef0>] _raw_write_lock_bh+0x40/0x80
[ 2136.388106] [<ffffffff836b37df>] ? rawsock_release+0x4f/0xa0
[ 2136.388106] [<ffffffff836b37df>] rawsock_release+0x4f/0xa0
[ 2136.388106] [<ffffffff8321cfe8>] sock_release+0x18/0x70
[ 2136.388106] [<ffffffff8321d069>] sock_close+0x29/0x30
[ 2136.388106] [<ffffffff81236bca>] __fput+0x11a/0x2c0
[ 2136.388106] [<ffffffff81236d85>] fput+0x15/0x20
[ 2136.388106] [<ffffffff8321de34>] sys_accept4+0x1b4/0x200
[ 2136.388106] [<ffffffff837c165c>] ? _raw_spin_unlock_irq+0x4c/0x80
[ 2136.388106] [<ffffffff837c1669>] ? _raw_spin_unlock_irq+0x59/0x80
[ 2136.388106] [<ffffffff837c2565>] ? sysret_check+0x22/0x5d
[ 2136.388106] [<ffffffff8321de8b>] sys_accept+0xb/0x10
[ 2136.388106] [<ffffffff837c2539>] system_call_fastpath+0x16/0x1b
[ 2136.388106] Code: ec 04 00 0f 85 ea 03 00 00 be d5 0b 00 00 48 c7 c7
8a c1 40 84 e8 b1 a5 f8 ff 31 c0 e9 d4 03 00 00 66 2e 0f 1f 84 00 00 00
00 00 <49> 81 7d 00 60 73 5e 85 b8 01 00 00 00 44 0f 44 e0 83 fe 01 77
[ 2136.388106] RIP [<ffffffff8114e400>] __lock_acquire+0xc0/0x4b0
[ 2136.388106] RSP <ffff8800130b3ca8>
[ 2136.388106] CR2: 00000000000003b0
[ 2136.388106] ---[ end trace 6d450e935ee18982 ]---
[ 2136.388106] Kernel panic - not syncing: Fatal exception in interrupt

rawsock_release() should test if sock->sk is NULL before calling
sock_orphan()/sock_put()

Reported-by: Sasha Levin <[email protected]>
Tested-by: Sasha Levin <[email protected]>
Cc: [email protected]
Signed-off-by: Eric Dumazet <[email protected]>
Signed-off-by: Samuel Ortiz <[email protected]>
---
net/nfc/rawsock.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c
index ec1134c..8b8a6a2 100644
--- a/net/nfc/rawsock.c
+++ b/net/nfc/rawsock.c
@@ -54,7 +54,10 @@ static int rawsock_release(struct socket *sock)
{
struct sock *sk = sock->sk;

- pr_debug("sock=%p\n", sock);
+ pr_debug("sock=%p sk=%p\n", sock, sk);
+
+ if (!sk)
+ return 0;

sock_orphan(sk);
sock_put(sk);
--
1.7.10