In nfc_llcp_recv_hdlc() and nfc_llcp_recv_disc(), when the socket
state is LLCP_CLOSED, the code correctly calls release_sock() and
nfc_llcp_sock_put() but fails to return. Execution falls through to
the remainder of the function, which calls release_sock() and
nfc_llcp_sock_put() again. This results in a double release_sock()
and a refcount underflow via double nfc_llcp_sock_put(), leading to
a use-after-free.
Add the missing return statements after the LLCP_CLOSED branches
in both functions to prevent the fall-through.
Bug: 499350302
Fixes: d646960f79 ("NFC: Initial LLCP support")
Signed-off-by: Junxi Qian <qjx1298677004@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260408081006.3723-1-qjx1298677004@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
(cherry picked from commit 2b5dd4632966c39da6ba74dbc8689b309065e82c)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: I041f20fc1fea32f715d2646579fab071e58688d8
d3d47118ab