8ddaea033d
[ Upstream commit febccb39255f9df35527b88c953b2e0deae50e53 ]
In case of im_protocols value is 1 and tm_protocols value is 0 this
combination successfully passes the check
'if (!im_protocols && !tm_protocols)' in the nfc_start_poll().
But then after pn533_poll_create_mod_list() call in pn533_start_poll()
poll mod list will remain empty and dev->poll_mod_count will remain 0
which lead to division by zero.
Normally no im protocol has value 1 in the mask, so this combination is
not expected by driver. But these protocol values actually come from
userspace via Netlink interface (NFC_CMD_START_POLL operation). So a
broken or malicious program may pass a message containing a "bad"
combination of protocol parameter values so that dev->poll_mod_count
is not incremented inside pn533_poll_create_mod_list(), thus leading
to division by zero.
Call trace looks like:
nfc_genl_start_poll()
nfc_start_poll()
->start_poll()
pn533_start_poll()
Add poll mod list filling check.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes:
|
||
|---|---|---|
| .. | ||
| fdp | ||
| microread | ||
| nfcmrvl | ||
| nxp-nci | ||
| pn533 | ||
| pn544 | ||
| s3fwrn5 | ||
| st21nfca | ||
| st95hf | ||
| st-nci | ||
| Kconfig | ||
| Makefile | ||
| mei_phy.c | ||
| mei_phy.h | ||
| nfcsim.c | ||
| port100.c | ||
| trf7970a.c | ||