6.12-stable review patch. If anyone has any objections, please let me know.
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From: Sean Heelan seanheelan@gmail.com
commit 1e440d5b25b7efccb3defe542a73c51005799a5f upstream.
krb_authenticate frees sess->user and does not set the pointer to NULL. It calls ksmbd_krb5_authenticate to reinitialise sess->user but that function may return without doing so. If that happens then smb2_sess_setup, which calls krb_authenticate, will be accessing free'd memory when it later uses sess->user.
Cc: stable@vger.kernel.org Signed-off-by: Sean Heelan seanheelan@gmail.com Acked-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/smb/server/smb2pdu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -1599,8 +1599,10 @@ static int krb5_authenticate(struct ksmb if (prev_sess_id && prev_sess_id != sess->id) destroy_previous_session(conn, sess->user, prev_sess_id);
- if (sess->state == SMB2_SESSION_VALID) + if (sess->state == SMB2_SESSION_VALID) { ksmbd_free_user(sess->user); + sess->user = NULL; + }
retval = ksmbd_krb5_authenticate(sess, in_blob, in_len, out_blob, &out_len);