commit: 7ac28817536797fd40e9646452183606f9e17f71 From: Dan Rosenberg <[email protected]> Date: Fri, 24 Jun 2011 08:38:05 -0400 Subject: [PATCH] Bluetooth: Prevent buffer overflow in l2cap config request
A remote user can provide a small value for the command size field in the command header of an l2cap configuration request, resulting in an integer underflow when subtracting the size of the configuration request header. This results in copying a very large amount of data via memcpy() and destroying the kernel heap. Check for underflow. Signed-off-by: Dan Rosenberg <[email protected]> Cc: stable <[email protected]> Signed-off-by: Gustavo F. Padovan <[email protected]> --- net/bluetooth/l2cap_core.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 56fdd91..7d8a66b 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -2334,7 +2334,7 @@ static inline int l2cap_config_req(struct l2cap_conn *conn, struct l2cap_cmd_hdr /* Reject if config buffer is too small. */ len = cmd_len - sizeof(*req); - if (chan->conf_len + len > sizeof(chan->conf_req)) { + if (len < 0 || chan->conf_len + len > sizeof(chan->conf_req)) { l2cap_send_cmd(conn, cmd->ident, L2CAP_CONF_RSP, l2cap_build_conf_rsp(chan, rsp, L2CAP_CONF_REJECT, flags), rsp); _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
