diff options
| author | Gwendal Grignou <gwendal@chromium.org> | 2016-03-08 09:13:52 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-24 10:57:00 +0100 |
| commit | 9c53f0065310ac5e85f6f3b278b6a31e940f78f9 (patch) | |
| tree | 9995e75065540de0e36de6a7e81d8a9fcd3eeadd /include/linux/mfd | |
| parent | 01865de78a64b4352d77f66e4e9bb0b13ed75777 (diff) | |
platform/chrome: cros_ec_dev - Fix security issue
commit 5d749d0bbe811c10d9048cde6dfebc761713abfd upstream.
Prevent memory scribble by checking that ioctl buffer size parameters
are sane.
Without this check, on 32 bits system, if .insize = 0xffffffff - 20 and
.outsize the amount to scribble, we would overflow, allocate a small
amounts and be able to write outside of the malloc'ed area.
Adding a hard limit allows argument checking of the ioctl. With the
current EC, it is expected .insize and .outsize to be at around 512 bytes
or less.
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/mfd')
| -rw-r--r-- | include/linux/mfd/cros_ec.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h index 3ab3cede28ea..93c14e9df630 100644 --- a/include/linux/mfd/cros_ec.h +++ b/include/linux/mfd/cros_ec.h @@ -50,9 +50,11 @@ enum { EC_MSG_TX_TRAILER_BYTES, EC_MSG_RX_PROTO_BYTES = 3, - /* Max length of messages */ - EC_MSG_BYTES = EC_PROTO2_MAX_PARAM_SIZE + + /* Max length of messages for proto 2*/ + EC_PROTO2_MSG_BYTES = EC_PROTO2_MAX_PARAM_SIZE + EC_MSG_TX_PROTO_BYTES, + + EC_MAX_MSG_BYTES = 64 * 1024, }; /* |