Add sanity checks for both `tlv_len` and `tlv_bitmap_len` before
decoding data from `event_buf`.
This prevents any malicious or buggy firmware from overflowing
`event_buf` through large values for `tlv_len` or `tlv_bitmap_len`.
Suggested-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
.../net/wireless/marvell/mwifiex/11n_rxreorder.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c b/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c
index 735aac52bdc4..9ee3b9f1e9ce 100644
--- a/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c
+++ b/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c
@@ -921,6 +921,14 @@ void mwifiex_11n_rxba_sync_event(struct mwifiex_private *priv,
while (tlv_buf_left > sizeof(*tlv_rxba)) {
tlv_type = le16_to_cpu(tlv_rxba->header.type);
tlv_len = le16_to_cpu(tlv_rxba->header.len);
+ if (size_add(sizeof(tlv_rxba->header), tlv_len) > tlv_buf_left) {
+ mwifiex_dbg(priv->adapter, WARN,
+ "TLV size (%ld) overflows event_buf (%d)\n",
+ size_add(sizeof(tlv_rxba->header), tlv_len),
+ tlv_buf_left);
+ return;
+ }
+
if (tlv_type != TLV_TYPE_RXBA_SYNC) {
mwifiex_dbg(priv->adapter, ERROR,
"Wrong TLV id=0x%x\n", tlv_type);
@@ -929,6 +937,14 @@ void mwifiex_11n_rxba_sync_event(struct mwifiex_private *priv,
tlv_seq_num = le16_to_cpu(tlv_rxba->seq_num);
tlv_bitmap_len = le16_to_cpu(tlv_rxba->bitmap_len);
+ if (size_add(sizeof(*tlv_rxba), tlv_bitmap_len) > tlv_buf_left) {
+ mwifiex_dbg(priv->adapter, WARN,
+ "TLV size (%ld) overflows event_buf (%d)\n",
+ size_add(sizeof(*tlv_rxba), tlv_bitmap_len),
+ tlv_buf_left);
+ return;
+ }
+
mwifiex_dbg(priv->adapter, INFO,
"%pM tid=%d seq_num=%d bitmap_len=%d\n",
tlv_rxba->mac, tlv_rxba->tid, tlv_seq_num,
--
2.34.1Hi Gustavo,
kernel test robot noticed the following build warnings:
[auto build test WARNING on linus/master]
[also build test WARNING on v6.5-rc7 next-20230823]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Gustavo-A-R-Silva/wifi-mwifiex-Fix-tlv_buf_left-calculation/20230824-063517
base: linus/master
patch link: https://lore.kernel.org/r/587423b0737108effe82aefed4407daca39e9a51.1692829410.git.gustavoars%40kernel.org
patch subject: [PATCH 3/3] wifi: mwifiex: Sanity check tlv_len and tlv_bitmap_len
config: m68k-allyesconfig (https://download.01.org/0day-ci/archive/20230824/202308240844.leyoOwdG-lkp@intel.com/config)
compiler: m68k-linux-gcc (GCC) 13.2.0
reproduce: (https://download.01.org/0day-ci/archive/20230824/202308240844.leyoOwdG-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202308240844.leyoOwdG-lkp@intel.com/
All warnings (new ones prefixed by >>):
In file included from drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c:12:
drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c: In function 'mwifiex_11n_rxba_sync_event':
>> drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c:926:37: warning: format '%ld' expects argument of type 'long int', but argument 4 has type 'size_t' {aka 'unsigned int'} [-Wformat=]
926 | "TLV size (%ld) overflows event_buf (%d)\n",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
927 | size_add(sizeof(tlv_rxba->header), tlv_len),
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| |
| size_t {aka unsigned int}
drivers/net/wireless/marvell/mwifiex/main.h:199:51: note: in definition of macro 'mwifiex_dbg'
199 | _mwifiex_dbg(adapter, MWIFIEX_DBG_##mask, fmt, ##__VA_ARGS__)
| ^~~
drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c:926:50: note: format string is defined here
926 | "TLV size (%ld) overflows event_buf (%d)\n",
| ~~^
| |
| long int
| %d
drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c:942:37: warning: format '%ld' expects argument of type 'long int', but argument 4 has type 'size_t' {aka 'unsigned int'} [-Wformat=]
942 | "TLV size (%ld) overflows event_buf (%d)\n",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
943 | size_add(sizeof(*tlv_rxba), tlv_bitmap_len),
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| |
| size_t {aka unsigned int}
drivers/net/wireless/marvell/mwifiex/main.h:199:51: note: in definition of macro 'mwifiex_dbg'
199 | _mwifiex_dbg(adapter, MWIFIEX_DBG_##mask, fmt, ##__VA_ARGS__)
| ^~~
drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c:942:50: note: format string is defined here
942 | "TLV size (%ld) overflows event_buf (%d)\n",
| ~~^
| |
| long int
| %d
vim +926 drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c
904
905 /* This function handles rxba_sync event
906 */
907 void mwifiex_11n_rxba_sync_event(struct mwifiex_private *priv,
908 u8 *event_buf, u16 len)
909 {
910 struct mwifiex_ie_types_rxba_sync *tlv_rxba = (void *)event_buf;
911 u16 tlv_type, tlv_len;
912 struct mwifiex_rx_reorder_tbl *rx_reor_tbl_ptr;
913 u8 i, j;
914 u16 seq_num, tlv_seq_num, tlv_bitmap_len;
915 int tlv_buf_left = len;
916 int ret;
917 u8 *tmp;
918
919 mwifiex_dbg_dump(priv->adapter, EVT_D, "RXBA_SYNC event:",
920 event_buf, len);
921 while (tlv_buf_left > sizeof(*tlv_rxba)) {
922 tlv_type = le16_to_cpu(tlv_rxba->header.type);
923 tlv_len = le16_to_cpu(tlv_rxba->header.len);
924 if (size_add(sizeof(tlv_rxba->header), tlv_len) > tlv_buf_left) {
925 mwifiex_dbg(priv->adapter, WARN,
> 926 "TLV size (%ld) overflows event_buf (%d)\n",
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
On Wed, Aug 23, 2023 at 3:33 PM Gustavo A. R. Silva
<gustavoars@kernel.org> wrote:
>
> Add sanity checks for both `tlv_len` and `tlv_bitmap_len` before
> decoding data from `event_buf`.
>
> This prevents any malicious or buggy firmware from overflowing
> `event_buf` through large values for `tlv_len` or `tlv_bitmap_len`.
>
> Suggested-by: Dan Williams <dcbw@redhat.com>
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Justin Stitt <justinstitt@google.com>
> ---
> .../net/wireless/marvell/mwifiex/11n_rxreorder.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c b/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c
> index 735aac52bdc4..9ee3b9f1e9ce 100644
> --- a/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c
> +++ b/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c
> @@ -921,6 +921,14 @@ void mwifiex_11n_rxba_sync_event(struct mwifiex_private *priv,
> while (tlv_buf_left > sizeof(*tlv_rxba)) {
> tlv_type = le16_to_cpu(tlv_rxba->header.type);
> tlv_len = le16_to_cpu(tlv_rxba->header.len);
> + if (size_add(sizeof(tlv_rxba->header), tlv_len) > tlv_buf_left) {
> + mwifiex_dbg(priv->adapter, WARN,
> + "TLV size (%ld) overflows event_buf (%d)\n",
> + size_add(sizeof(tlv_rxba->header), tlv_len),
> + tlv_buf_left);
> + return;
> + }
> +
> if (tlv_type != TLV_TYPE_RXBA_SYNC) {
> mwifiex_dbg(priv->adapter, ERROR,
> "Wrong TLV id=0x%x\n", tlv_type);
> @@ -929,6 +937,14 @@ void mwifiex_11n_rxba_sync_event(struct mwifiex_private *priv,
>
> tlv_seq_num = le16_to_cpu(tlv_rxba->seq_num);
> tlv_bitmap_len = le16_to_cpu(tlv_rxba->bitmap_len);
> + if (size_add(sizeof(*tlv_rxba), tlv_bitmap_len) > tlv_buf_left) {
> + mwifiex_dbg(priv->adapter, WARN,
> + "TLV size (%ld) overflows event_buf (%d)\n",
> + size_add(sizeof(*tlv_rxba), tlv_bitmap_len),
> + tlv_buf_left);
> + return;
> + }
> +
> mwifiex_dbg(priv->adapter, INFO,
> "%pM tid=%d seq_num=%d bitmap_len=%d\n",
> tlv_rxba->mac, tlv_rxba->tid, tlv_seq_num,
> --
> 2.34.1
>
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