Commit 765a7070 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

megasas: fix guest-triggered memory leak 



If the guest sets the sglist size to a value >=2GB, megasas_handle_dcmd
will return MFI_STAT_MEMORY_NOT_AVAILABLE without freeing the memory.
Avoid this by returning only the status from map_dcmd, and loading
cmd->iov_size in the caller.

Reported-by: default avatarLi Qiang <liqiang6-s@360.cn>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent bf7bb91e

hw/scsi/megasas.c

+6 −5
Original line number Diff line number Diff line
@@ -683,14 +683,14 @@ static int megasas_map_dcmd(MegasasState *s, MegasasCmd *cmd) 
        trace_megasas_dcmd_invalid_sge(cmd->index,

                                       cmd->frame->header.sge_count);

        cmd->iov_size = 0;

        return -1;

        return -EINVAL;

    }

    iov_pa = megasas_sgl_get_addr(cmd, &cmd->frame->dcmd.sgl);

    iov_size = megasas_sgl_get_len(cmd, &cmd->frame->dcmd.sgl);

    pci_dma_sglist_init(&cmd->qsg, PCI_DEVICE(s), 1);

    qemu_sglist_add(&cmd->qsg, iov_pa, iov_size);

    cmd->iov_size = iov_size;

    return cmd->iov_size;

    return 0;

}



static void megasas_finish_dcmd(MegasasCmd *cmd, uint32_t iov_size)
@@ -1559,19 +1559,20 @@ static const struct dcmd_cmd_tbl_t { 


static int megasas_handle_dcmd(MegasasState *s, MegasasCmd *cmd)

{

    int opcode, len;

    int opcode;

    int retval = 0;

    size_t len;

    const struct dcmd_cmd_tbl_t *cmdptr = dcmd_cmd_tbl;



    opcode = le32_to_cpu(cmd->frame->dcmd.opcode);

    trace_megasas_handle_dcmd(cmd->index, opcode);

    len = megasas_map_dcmd(s, cmd);

    if (len < 0) {

    if (megasas_map_dcmd(s, cmd) < 0) {

        return MFI_STAT_MEMORY_NOT_AVAILABLE;

    }

    while (cmdptr->opcode != -1 && cmdptr->opcode != opcode) {

        cmdptr++;

    }

    len = cmd->iov_size;

    if (cmdptr->opcode == -1) {

        trace_megasas_dcmd_unhandled(cmd->index, opcode, len);

        retval = megasas_dcmd_dummy(s, cmd);