Re: [PATCH 2/6] Skip stale device config when checking child compatibility

[Paul Durrant <xadimgnik@xxxxxxxxx>]

On 17/06/2021 13:33, Owen Smith wrote:
> When a device is updated, the Enum key for the old binding is not deleted.
> This can lead to a device binding that is not in use (has been replaced by
> a later binding) triggering the coinstaller to fail the upgrade to a newer
> version. This is especially prevelent when the older stale information was
> bound to a revision that is not present in the new driver INF file.
>
> This fix ignores the stale entries under the Enum key when performing the
> compatibility checks.
>
> e.g.
> tag 8.2.1 has 0x08000009 to 0x08000009 for its bindings
> tag 9.0.0 has 0x08000009 to 0x09000007 for its bindings
> commit a9631142d0be removed v8 revisions, leaving only 0x0900000x revisions
> It should be possible to upgrade from tag 8.2.1 to tag 9.0.0 and then to
> commits after a9631142d0be. At each stage of this upgrade, the revisions
> overlap, even if the initial and end revisions do not have an overlap.
> It is not possible to upgrade directly from tag 8.2.1 to commit a9631142d0be,
> as there is no common revision that can be used.
>
> Signed-off-by: Owen Smith <owen.smith@xxxxxxxxxx>
Acked-by: Paul Durrant <paul@xxxxxxx>

> ---
>   src/coinst/coinst.c | 37 +++++++++++++++++++++++++++++++------
>   1 file changed, 31 insertions(+), 6 deletions(-)
>
> diff --git a/src/coinst/coinst.c b/src/coinst/coinst.c
> index c29ce59..8dc290c 100644
> --- a/src/coinst/coinst.c
> +++ b/src/coinst/coinst.c
> @@ -575,7 +575,8 @@ fail1:
>   static BOOLEAN
>   GetDriverKeyName(
>       IN  HKEY    DeviceKey,
> -    OUT PTCHAR  *Name
> +    OUT PTCHAR  *Name,
> +    OUT DWORD   *ConfigFlags
>       )
>   {
>       HRESULT     Error;
> @@ -586,6 +587,7 @@ GetDriverKeyName(
>       DWORD       Index;
>       HKEY        SubKey;
>       PTCHAR      DriverKeyName;
> +    DWORD       Flags;
>   
>       Error = RegQueryInfoKey(DeviceKey,
>                               NULL,
> @@ -612,9 +614,11 @@ GetDriverKeyName(
>   
>       SubKey = NULL;
>       DriverKeyName = NULL;
> +    Flags = 0;
>   
>       for (Index = 0; Index < SubKeys; Index++) {
>           DWORD       MaxValueLength;
> +        DWORD       ConfigFlagsLength;
>           DWORD       DriverKeyNameLength;
>           DWORD       Type;
>   
> @@ -661,6 +665,18 @@ GetDriverKeyName(
>               goto fail4;
>           }
>   
> +        ConfigFlagsLength = (DWORD)sizeof(DWORD);
> +
> +        Error = RegQueryValueEx(SubKey,
> +                                "ConfigFlags",
> +                                NULL,
> +                                &Type,
> +                                (LPBYTE)&Flags,
> +                                &ConfigFlagsLength);
> +        if (Error != ERROR_SUCCESS ||
> +            Type != REG_DWORD)
> +            Flags = 0;
> +
>           DriverKeyNameLength = MaxValueLength + sizeof (TCHAR);
>   
>           DriverKeyName = calloc(1, DriverKeyNameLength);
> @@ -679,6 +695,7 @@ GetDriverKeyName(
>   
>           free(DriverKeyName);
>           DriverKeyName = NULL;
> +        Flags = 0;
>   
>           RegCloseKey(SubKey);
>           SubKey = NULL;
> @@ -692,6 +709,8 @@ GetDriverKeyName(
>       free(SubKeyName);
>   
>       *Name = DriverKeyName;
> +    if (ConfigFlags)
> +        *ConfigFlags = Flags;
>       return TRUE;
>   
>   fail5:
> @@ -851,7 +870,7 @@ found:
>           goto fail3;
>   
>       // Check for a bound driver
> -    Success = GetDriverKeyName(DeviceKey, &DriverKeyName);
> +    Success = GetDriverKeyName(DeviceKey, &DriverKeyName, NULL);
>       if (!Success)
>           goto fail4;
>   
> @@ -1452,6 +1471,7 @@ SupportChildDrivers(
>       PTCHAR          SubKeyName;
>       HKEY            DeviceKey;
>       PTCHAR          DriverKeyName;
> +    DWORD           ConfigFlags;
>       HKEY            DriverKey;
>       PTCHAR          MatchingDeviceID;
>       DWORD           Index;
> @@ -1511,20 +1531,23 @@ SupportChildDrivers(
>           if (!Success)
>               goto fail5;
>   
> -        Success = GetDriverKeyName(DeviceKey, &DriverKeyName);
> +        Success = GetDriverKeyName(DeviceKey, &DriverKeyName, &ConfigFlags);
>           if (!Success)
>               goto fail6;
>   
>           if (DriverKeyName == NULL)
>               goto loop1;
>   
> +        if (ConfigFlags & 0x20)
> +            goto loop2;
> +
>           Success = OpenDriverKey(DriverKeyName, &DriverKey);
>           if (!Success)
> -            goto loop2;
> +            goto loop3;
>   
>           Success = GetMatchingDeviceID(DriverKey, &MatchingDeviceID);
>           if (!Success)
> -            goto loop3;
> +            goto loop4;
>   
>           Success = SupportDeviceID(MatchingDeviceID, NewBinding);
>           if (!Success)
> @@ -1532,9 +1555,11 @@ SupportChildDrivers(
>   
>           free(MatchingDeviceID);
>   
> -    loop3:
> +    loop4:
>           RegCloseKey(DriverKey);
>   
> +    loop3:
> +
>       loop2:
>           free(DriverKeyName);
>