tmakin/ack-tegra
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Bluetooth: btintel: Check dsbr size from EFI variable

Browse Source 
[ Upstream commit 3aa1dc3c9060e335e82e9c182bf3d1db29220b1b ]

Since the size of struct btintel_dsbr is already known, we can just
start there instead of querying the EFI variable size. If the final
result doesn't match what we expect also fail. This fixes a stack buffer
overflow when the EFI variable is larger than struct btintel_dsbr.

Reported-by: zepta <z3ptaa@gmail.com>
Closes: https://lore.kernel.org/all/CAPBS6KoaWV9=dtjTESZiU6KK__OZX0KpDk-=JEH8jCHFLUYv3Q@mail.gmail.com
Fixes: eb9e749c01 ("Bluetooth: btintel: Allow configuring drive strength of BRI")
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Kees Cook
2025-05-20 09:31:35 -07:00
committed by Greg Kroah-Hartman
parent 1750c3f1d9
commit 9427f6081f
1 changed files with 2 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
drivers/bluetooth/btintel.c
View File

@@ -2705,7 +2705,7 @@ static int btintel_uefi_get_dsbr(u32 *dsbr_var)
} __packed data;
efi_status_t status;
unsigned long data_size = 0;
unsigned long data_size = sizeof(data);
efi_guid_t guid = EFI_GUID(0xe65d8884, 0xd4af, 0x4b20, 0x8d, 0x03,
0x77, 0x2e, 0xcc, 0x3d, 0xa5, 0x31);
@@ -2715,16 +2715,10 @@ static int btintel_uefi_get_dsbr(u32 *dsbr_var)
if (!efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE))
return -EOPNOTSUPP;
status = efi.get_variable(BTINTEL_EFI_DSBR, &guid, NULL, &data_size,
NULL);
if (status != EFI_BUFFER_TOO_SMALL || !data_size)
return -EIO;
status = efi.get_variable(BTINTEL_EFI_DSBR, &guid, NULL, &data_size,
&data);
if (status != EFI_SUCCESS)
if (status != EFI_SUCCESS || data_size != sizeof(data))
return -ENXIO;
*dsbr_var = data.dsbr;