Re: [Qemu-devel] [PATCH] replace fixed str limit by g_strdup_printf

[Alex Williamson]

On Wed, 24 Feb 2016 00:22:02 -0800
Neo Jia <address@hidden> wrote:

> A trivial change to remove string limit by using g_strdup_printf
> and g_strconcat
> 
> Tested-by: Neo Jia <address@hidden>
> Signed-off-by: Neo Jia <address@hidden>
> Signed-off-by: Kirti Wankhede <address@hidden>
> ---
>  hw/vfio/pci.c | 19 ++++++++++++-------
>  1 file changed, 12 insertions(+), 7 deletions(-)
> 
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index bfe421528618..795e035a6a9b 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -874,7 +874,7 @@ static void vfio_pci_size_rom(VFIOPCIDevice *vdev)
>      uint32_t orig, size = cpu_to_le32((uint32_t)PCI_ROM_ADDRESS_MASK);
>      off_t offset = vdev->config_offset + PCI_ROM_ADDRESS;
>      DeviceState *dev = DEVICE(vdev);
> -    char name[32];
> +    char *name;
>      int fd = vdev->vbasedev.fd;
>  
>      if (vdev->pdev.romfile || !vdev->pdev.rom_bar) {
> @@ -917,16 +917,18 @@ static void vfio_pci_size_rom(VFIOPCIDevice *vdev)
>  
>      trace_vfio_pci_size_rom(vdev->vbasedev.name, size);
>  
> -    snprintf(name, sizeof(name), "vfio[%s].rom", vdev->vbasedev.name);
> +    name = g_strdup_printf("vfio[%s].rom", vdev->vbasedev.name);
>  
>      memory_region_init_io(&vdev->pdev.rom, OBJECT(vdev),
>                            &vfio_rom_ops, vdev, name, size);
> +    g_free(name);
>  
>      pci_register_bar(&vdev->pdev, PCI_ROM_SLOT,
>                       PCI_BASE_ADDRESS_SPACE_MEMORY, &vdev->pdev.rom);
>  
>      vdev->pdev.has_rom = true;
>      vdev->rom_read_failed = false;
> +

Stray extra whitespace

>  }
>  
>  void vfio_vga_write(void *opaque, hwaddr addr,
> @@ -1318,7 +1320,7 @@ static void vfio_map_bar(VFIOPCIDevice *vdev, int nr)
>  {
>      VFIOBAR *bar = &vdev->bars[nr];
>      uint64_t size = bar->region.size;
> -    char name[64];
> +    char *name;

If you include my latest patch series[1], I think you'll find that the
limit here no longer exists.  Thanks,

Alex

[1] http://lists.gnu.org/archive/html/qemu-devel/2016-02/msg05089.html


>      uint32_t pci_bar;
>      uint8_t type;
>      int ret;
> @@ -1328,8 +1330,6 @@ static void vfio_map_bar(VFIOPCIDevice *vdev, int nr)
>          return;
>      }
>  
> -    snprintf(name, sizeof(name), "VFIO %s BAR %d", vdev->vbasedev.name, nr);
> -
>      /* Determine what type of BAR this is for registration */
>      ret = pread(vdev->vbasedev.fd, &pci_bar, sizeof(pci_bar),
>                  vdev->config_offset + PCI_BASE_ADDRESS_0 + (4 * nr));
> @@ -1338,6 +1338,8 @@ static void vfio_map_bar(VFIOPCIDevice *vdev, int nr)
>          return;
>      }
>  
> +    name = g_strdup_printf("VFIO %s BAR %d", vdev->vbasedev.name, nr);
> +
>      pci_bar = le32_to_cpu(pci_bar);
>      bar->ioport = (pci_bar & PCI_BASE_ADDRESS_SPACE_IO);
>      bar->mem64 = bar->ioport ? 0 : (pci_bar & PCI_BASE_ADDRESS_MEM_TYPE_64);
> @@ -1357,7 +1359,8 @@ static void vfio_map_bar(VFIOPCIDevice *vdev, int nr)
>          size = vdev->msix->table_offset & qemu_real_host_page_mask;
>      }
>  
> -    strncat(name, " mmap", sizeof(name) - strlen(name) - 1);
> +    name = g_strconcat(name, " mmap", NULL);
> +
>      if (vfio_mmap_region(OBJECT(vdev), &bar->region, &bar->region.mem,
>                        &bar->region.mmap_mem, &bar->region.mmap,
>                        size, 0, name)) {
> @@ -1372,7 +1375,8 @@ static void vfio_map_bar(VFIOPCIDevice *vdev, int nr)
>                                        PCI_MSIX_ENTRY_SIZE));
>  
>          size = start < bar->region.size ? bar->region.size - start : 0;
> -        strncat(name, " msix-hi", sizeof(name) - strlen(name) - 1);
> +        name = g_strconcat(name, " msix-hi", NULL);
> +
>          /* VFIOMSIXInfo contains another MemoryRegion for this mapping */
>          if (vfio_mmap_region(OBJECT(vdev), &bar->region, &bar->region.mem,
>                            &vdev->msix->mmap_mem,
> @@ -1382,6 +1386,7 @@ static void vfio_map_bar(VFIOPCIDevice *vdev, int nr)
>      }
>  
>      vfio_bar_quirk_setup(vdev, nr);
> +    g_free(name);
>  }
>  
>  static void vfio_map_bars(VFIOPCIDevice *vdev)