From: Nicholas Bellinger Date: Mon, 18 Nov 2013 18:55:10 +0000 (-0800) Subject: iscsi-target: Do not reject non-immediate CmdSNs exceeding MaxCmdSN X-Git-Tag: firefly_0821_release~176^2~4892^2~10 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ea7e32bec1b9d9e5b159d80ceb563c702e28b02a;p=firefly-linux-kernel-4.4.55.git iscsi-target: Do not reject non-immediate CmdSNs exceeding MaxCmdSN This patch changes iscsit_sequence_cmd() logic to no longer reject non-immediate CmdSNs that exceed MaxCmdSN with a protocol error, but instead silently ignore them. This is done to correctly follow RFC-3720 Section 3.2.2.1: For non-immediate commands, the CmdSN field can take any value from ExpCmdSN to MaxCmdSN inclusive. The target MUST silently ignore any non-immediate command outside of this range or non- immediate duplicates within the range. Reported-by: Santosh Kulkarni Signed-off-by: Nicholas Bellinger --- diff --git a/drivers/target/iscsi/iscsi_target_core.h b/drivers/target/iscsi/iscsi_target_core.h index f2094d2f8eef..8dcb3c1aa801 100644 --- a/drivers/target/iscsi/iscsi_target_core.h +++ b/drivers/target/iscsi/iscsi_target_core.h @@ -193,6 +193,7 @@ enum recover_cmdsn_ret_table { CMDSN_NORMAL_OPERATION = 0, CMDSN_LOWER_THAN_EXP = 1, CMDSN_HIGHER_THAN_EXP = 2, + CMDSN_MAXCMDSN_OVERRUN = 3, }; /* Used for iscsi_handle_immediate_data() return values */ diff --git a/drivers/target/iscsi/iscsi_target_util.c b/drivers/target/iscsi/iscsi_target_util.c index 45b8fd13fa72..9064926a0370 100644 --- a/drivers/target/iscsi/iscsi_target_util.c +++ b/drivers/target/iscsi/iscsi_target_util.c @@ -242,9 +242,9 @@ static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cm */ if (iscsi_sna_gt(cmdsn, sess->max_cmd_sn)) { pr_err("Received CmdSN: 0x%08x is greater than" - " MaxCmdSN: 0x%08x, protocol error.\n", cmdsn, + " MaxCmdSN: 0x%08x, ignoring.\n", cmdsn, sess->max_cmd_sn); - ret = CMDSN_ERROR_CANNOT_RECOVER; + ret = CMDSN_MAXCMDSN_OVERRUN; } else if (cmdsn == sess->exp_cmd_sn) { sess->exp_cmd_sn++; @@ -303,14 +303,16 @@ int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd, ret = CMDSN_HIGHER_THAN_EXP; break; case CMDSN_LOWER_THAN_EXP: + case CMDSN_MAXCMDSN_OVERRUN: + default: cmd->i_state = ISTATE_REMOVE; iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state); - ret = cmdsn_ret; - break; - default: - reason = ISCSI_REASON_PROTOCOL_ERROR; - reject = true; - ret = cmdsn_ret; + /* + * Existing callers for iscsit_sequence_cmd() will silently + * ignore commands with CMDSN_LOWER_THAN_EXP, so force this + * return for CMDSN_MAXCMDSN_OVERRUN as well.. + */ + ret = CMDSN_LOWER_THAN_EXP; break; } mutex_unlock(&conn->sess->cmdsn_mutex);