xemu/hw/nvram
Laszlo Ersek 4318432ccd hw/nvram/fw_cfg: fix FWCfgDataGeneratorClass::get_data() consumption
The documentation on g_byte_array_free()
<https://developer.gnome.org/glib/stable/glib-Byte-Arrays.html#g-byte-array-free>
says:

> Returns
>
> the element data if free_segment is FALSE, otherwise NULL. The element
> data should be freed using g_free().

Because we currently call g_byte_array_free() with free_segment=TRUE, we
end up passing data=NULL to fw_cfg_add_file().

On the plus side, fw_cfg_data_read() and fw_cfg_dma_transfer() both deal
with NULL data gracefully: QEMU does not crash when the guest reads such
an item, the guest just gets a properly sized, but zero-filled blob.

However, the bug breaks UEFI HTTPS boot, as the IANA_TLS_CIPHER array,
generated otherwise correctly by the "tls-cipher-suites" object, is in
effect replaced with a zero blob.

Fix the issue by passing free_segment=FALSE to g_byte_array_free():

- the caller (fw_cfg_add_from_generator()) temporarily assumes ownership
  of the generated byte array,

- then ownership of the byte array is transfered to fw_cfg, as
  fw_cfg_add_file() links (not copies) "data" into fw_cfg.

Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Cc: "Philippe Mathieu-Daudé" <philmd@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Fixes: 3203148917
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20200916151510.22767-1-lersek@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-09-18 17:18:18 +02:00
..
chrp_nvram.c nvram: Exit QEMU if NVRAM cannot contain all -prom-env data 2020-08-14 13:34:31 +10:00
ds1225y.c Use DECLARE_*CHECKER* macros 2020-09-09 09:27:09 -04:00
eeprom93xx.c misc: Replace zero-length arrays with flexible array member (automatic) 2020-03-16 22:07:42 +01:00
eeprom_at24c.c Use DECLARE_*CHECKER* macros 2020-09-09 09:27:09 -04:00
fw_cfg.c hw/nvram/fw_cfg: fix FWCfgDataGeneratorClass::get_data() consumption 2020-09-18 17:18:18 +02:00
Kconfig hw/nvram/Kconfig: Restrict CHRP NVRAM to machines using OpenBIOS or SLOF 2020-01-07 12:08:39 +01:00
mac_nvram.c nvram: Exit QEMU if NVRAM cannot contain all -prom-env data 2020-08-14 13:34:31 +10:00
meson.build hw/nvram: NPCM7xx OTP device model 2020-09-14 14:24:59 +01:00
npcm7xx_otp.c hw/nvram: NPCM7xx OTP device model 2020-09-14 14:24:59 +01:00
nrf51_nvm.c qdev: set properties with device_class_set_props() 2020-01-24 20:59:15 +01:00
spapr_nvram.c Use DECLARE_*CHECKER* macros 2020-09-09 09:27:09 -04:00
trace-events hw/nvram/mac_nvram: Convert debug printf()s to trace events 2020-05-27 15:29:36 +10:00
trace.h trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00