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    Subject[PATCH 3.2 007/107] target/iscsi: Fix double free of a TUR followed by a solicited NOPOUT
    3.2.72-rc1 review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Alexei Potashnik <alexei@purestorage.com>

    commit 9547308bda296b6f69876c840a0291fcfbeddbb8 upstream.

    Make sure all non-READ SCSI commands get targ_xfer_tag initialized
    to 0xffffffff, not just WRITEs.

    Double-free of a TUR cmd object occurs under the following scenario:

    1. TUR received (targ_xfer_tag is uninitialized and left at 0)
    2. TUR status sent
    3. First unsolicited NOPIN is sent to initiator (gets targ_xfer_tag of 0)
    4. NOPOUT for NOPIN (with TTT=0) arrives
    - its ExpStatSN acks TUR status, TUR is queued for removal
    - LIO tries to find NOPIN with TTT=0, but finds the same TUR instead,
    TUR is queued for removal for the 2nd time

    (Drop unbalanced conditional bracket usage - nab)

    Signed-off-by: Alexei Potashnik <alexei@purestorage.com>
    Signed-off-by: Spencer Baugh <sbaugh@catern.com>
    Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
    [bwh: Backported to 3.2:
    - Adjust context
    - Keep the braces around the if-block]
    Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
    ---
    --- a/drivers/target/iscsi/iscsi_target.c
    +++ b/drivers/target/iscsi/iscsi_target.c
    @@ -979,7 +979,7 @@ static int iscsit_handle_scsi_cmd(
    if (cmd->targ_xfer_tag == 0xFFFFFFFF)
    cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
    spin_unlock_bh(&conn->sess->ttt_lock);
    - } else if (hdr->flags & ISCSI_FLAG_CMD_WRITE)
    + } else
    cmd->targ_xfer_tag = 0xFFFFFFFF;
    cmd->cmd_sn = hdr->cmdsn;
    cmd->exp_stat_sn = hdr->exp_statsn;


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