4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Konstantin Shelekhin <k.shelekhin@xxxxxxxxx> [ Upstream commit 801f287c93ff95582b0a2d2163f12870a2f076d4 ] The function lio_target_nacl_info_show() uses sprintf() in a loop to print details for every iSCSI connection in a session without checking for the buffer length. With enough iSCSI connections it's possible to overflow the buffer provided by configfs and corrupt the memory. This patch replaces sprintf() with sysfs_emit_at() that checks for buffer boundries. Signed-off-by: Konstantin Shelekhin <k.shelekhin@xxxxxxxxx> Link: https://lore.kernel.org/r/20230722152657.168859-2-k.shelekhin@xxxxxxxxx Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/target/iscsi/iscsi_target_configfs.c | 54 ++++++++++---------- 1 file changed, 27 insertions(+), 27 deletions(-) diff --git a/drivers/target/iscsi/iscsi_target_configfs.c b/drivers/target/iscsi/iscsi_target_configfs.c index d25cadc4f4f11..ac071abae7e90 100644 --- a/drivers/target/iscsi/iscsi_target_configfs.c +++ b/drivers/target/iscsi/iscsi_target_configfs.c @@ -516,102 +516,102 @@ static ssize_t lio_target_nacl_info_show(struct config_item *item, char *page) spin_lock_bh(&se_nacl->nacl_sess_lock); se_sess = se_nacl->nacl_sess; if (!se_sess) { - rb += sprintf(page+rb, "No active iSCSI Session for Initiator" + rb += sysfs_emit_at(page, rb, "No active iSCSI Session for Initiator" " Endpoint: %s\n", se_nacl->initiatorname); } else { sess = se_sess->fabric_sess_ptr; - rb += sprintf(page+rb, "InitiatorName: %s\n", + rb += sysfs_emit_at(page, rb, "InitiatorName: %s\n", sess->sess_ops->InitiatorName); - rb += sprintf(page+rb, "InitiatorAlias: %s\n", + rb += sysfs_emit_at(page, rb, "InitiatorAlias: %s\n", sess->sess_ops->InitiatorAlias); - rb += sprintf(page+rb, + rb += sysfs_emit_at(page, rb, "LIO Session ID: %u ISID: 0x%6ph TSIH: %hu ", sess->sid, sess->isid, sess->tsih); - rb += sprintf(page+rb, "SessionType: %s\n", + rb += sysfs_emit_at(page, rb, "SessionType: %s\n", (sess->sess_ops->SessionType) ? "Discovery" : "Normal"); - rb += sprintf(page+rb, "Session State: "); + rb += sysfs_emit_at(page, rb, "Session State: "); switch (sess->session_state) { case TARG_SESS_STATE_FREE: - rb += sprintf(page+rb, "TARG_SESS_FREE\n"); + rb += sysfs_emit_at(page, rb, "TARG_SESS_FREE\n"); break; case TARG_SESS_STATE_ACTIVE: - rb += sprintf(page+rb, "TARG_SESS_STATE_ACTIVE\n"); + rb += sysfs_emit_at(page, rb, "TARG_SESS_STATE_ACTIVE\n"); break; case TARG_SESS_STATE_LOGGED_IN: - rb += sprintf(page+rb, "TARG_SESS_STATE_LOGGED_IN\n"); + rb += sysfs_emit_at(page, rb, "TARG_SESS_STATE_LOGGED_IN\n"); break; case TARG_SESS_STATE_FAILED: - rb += sprintf(page+rb, "TARG_SESS_STATE_FAILED\n"); + rb += sysfs_emit_at(page, rb, "TARG_SESS_STATE_FAILED\n"); break; case TARG_SESS_STATE_IN_CONTINUE: - rb += sprintf(page+rb, "TARG_SESS_STATE_IN_CONTINUE\n"); + rb += sysfs_emit_at(page, rb, "TARG_SESS_STATE_IN_CONTINUE\n"); break; default: - rb += sprintf(page+rb, "ERROR: Unknown Session" + rb += sysfs_emit_at(page, rb, "ERROR: Unknown Session" " State!\n"); break; } - rb += sprintf(page+rb, "---------------------[iSCSI Session" + rb += sysfs_emit_at(page, rb, "---------------------[iSCSI Session" " Values]-----------------------\n"); - rb += sprintf(page+rb, " CmdSN/WR : CmdSN/WC : ExpCmdSN" + rb += sysfs_emit_at(page, rb, " CmdSN/WR : CmdSN/WC : ExpCmdSN" " : MaxCmdSN : ITT : TTT\n"); max_cmd_sn = (u32) atomic_read(&sess->max_cmd_sn); - rb += sprintf(page+rb, " 0x%08x 0x%08x 0x%08x 0x%08x" + rb += sysfs_emit_at(page, rb, " 0x%08x 0x%08x 0x%08x 0x%08x" " 0x%08x 0x%08x\n", sess->cmdsn_window, (max_cmd_sn - sess->exp_cmd_sn) + 1, sess->exp_cmd_sn, max_cmd_sn, sess->init_task_tag, sess->targ_xfer_tag); - rb += sprintf(page+rb, "----------------------[iSCSI" + rb += sysfs_emit_at(page, rb, "----------------------[iSCSI" " Connections]-------------------------\n"); spin_lock(&sess->conn_lock); list_for_each_entry(conn, &sess->sess_conn_list, conn_list) { - rb += sprintf(page+rb, "CID: %hu Connection" + rb += sysfs_emit_at(page, rb, "CID: %hu Connection" " State: ", conn->cid); switch (conn->conn_state) { case TARG_CONN_STATE_FREE: - rb += sprintf(page+rb, + rb += sysfs_emit_at(page, rb, "TARG_CONN_STATE_FREE\n"); break; case TARG_CONN_STATE_XPT_UP: - rb += sprintf(page+rb, + rb += sysfs_emit_at(page, rb, "TARG_CONN_STATE_XPT_UP\n"); break; case TARG_CONN_STATE_IN_LOGIN: - rb += sprintf(page+rb, + rb += sysfs_emit_at(page, rb, "TARG_CONN_STATE_IN_LOGIN\n"); break; case TARG_CONN_STATE_LOGGED_IN: - rb += sprintf(page+rb, + rb += sysfs_emit_at(page, rb, "TARG_CONN_STATE_LOGGED_IN\n"); break; case TARG_CONN_STATE_IN_LOGOUT: - rb += sprintf(page+rb, + rb += sysfs_emit_at(page, rb, "TARG_CONN_STATE_IN_LOGOUT\n"); break; case TARG_CONN_STATE_LOGOUT_REQUESTED: - rb += sprintf(page+rb, + rb += sysfs_emit_at(page, rb, "TARG_CONN_STATE_LOGOUT_REQUESTED\n"); break; case TARG_CONN_STATE_CLEANUP_WAIT: - rb += sprintf(page+rb, + rb += sysfs_emit_at(page, rb, "TARG_CONN_STATE_CLEANUP_WAIT\n"); break; default: - rb += sprintf(page+rb, + rb += sysfs_emit_at(page, rb, "ERROR: Unknown Connection State!\n"); break; } - rb += sprintf(page+rb, " Address %pISc %s", &conn->login_sockaddr, + rb += sysfs_emit_at(page, rb, " Address %pISc %s", &conn->login_sockaddr, (conn->network_transport == ISCSI_TCP) ? "TCP" : "SCTP"); - rb += sprintf(page+rb, " StatSN: 0x%08x\n", + rb += sysfs_emit_at(page, rb, " StatSN: 0x%08x\n", conn->stat_sn); } spin_unlock(&sess->conn_lock); -- 2.40.1