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author | Aleksandr Mishin <amishin@t-argos.ru> | 2024-08-27 10:48:22 +0200 |
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committer | Paolo Abeni <pabeni@redhat.com> | 2024-08-29 12:08:44 +0200 |
commit | febccb39255f9df35527b88c953b2e0deae50e53 (patch) | |
tree | 4d183d96abafffbda47a26fc0f2c0eebf342e371 /include | |
parent | Merge tag 'nf-24-08-28' of git://git.kernel.org/pub/scm/linux/kernel/git/netf... (diff) | |
download | linux-febccb39255f9df35527b88c953b2e0deae50e53.tar.xz linux-febccb39255f9df35527b88c953b2e0deae50e53.zip |
nfc: pn533: Add poll mod list filling check
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: dfccd0f58044 ("NFC: pn533: Add some polling entropy")
Signed-off-by: Aleksandr Mishin <amishin@t-argos.ru>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20240827084822.18785-1-amishin@t-argos.ru
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'include')
0 files changed, 0 insertions, 0 deletions