[PW_SID:1153957] Bluetooth: L2CAP: fix chan mode for LE_CONN_REQ + EXT_FLOWCTL pchan - #668
[PW_SID:1153957] Bluetooth: L2CAP: fix chan mode for LE_CONN_REQ + EXT_FLOWCTL pchan#668BluezTestBot wants to merge 1 commit into
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l2cap_new_connection() sets default value of channel mode to match the parent channel. l2cap_le_connect_req() left this at the default, and created L2CAP_MODE_EXT_FLOWCTL channels if listening pchan has that mode. This causes FLAG_DEFER_SETUP channels to reply to L2CAP_LE_CONN_REQ with L2CAP_ECRED_CONN_RSP, which is incorrect. It can also result to stack OOB write (of l2cap_alloc_cid determined values) in l2cap_ecred_rsp_defer(), as l2cap_le_connect_req() does not limit maximum number of deferred channels or check for duplicate ident. Fix by setting chan->mode correctly in l2cap_le_connect_req(). Also check channel mode in l2cap_ecred_rsp_defer(), and do WARN_ON_ONCE instead of OOB write to make it less brittle. Fixes: 15f02b9 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode") Signed-off-by: Pauli Virtanen <pav@iki.fi>
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l2cap_new_connection() sets default value of channel mode to match the
parent channel. l2cap_le_connect_req() left this at the default, and
created L2CAP_MODE_EXT_FLOWCTL channels if listening pchan has that
mode. This causes FLAG_DEFER_SETUP channels to reply to
L2CAP_LE_CONN_REQ with L2CAP_ECRED_CONN_RSP, which is incorrect.
It can also result to stack OOB write (of l2cap_alloc_cid determined
values) in l2cap_ecred_rsp_defer(), as l2cap_le_connect_req() does not
limit maximum number of deferred channels or check for duplicate ident.
Fix by setting chan->mode correctly in l2cap_le_connect_req().
Also check channel mode in l2cap_ecred_rsp_defer(), and do WARN_ON_ONCE
instead of OOB write to make it less brittle.
Fixes: 15f02b9 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode")
Signed-off-by: Pauli Virtanen pav@iki.fi
Notes:
This is another pre-existing issue from sashiko.dev reviews
net/bluetooth/l2cap_core.c | 8 ++++++++
1 file changed, 8 insertions(+)