The function amdgpu_virt_init_critical_region() contained an invalid
check for a negative init_hdr_offset value:
if (init_hdr_offset < 0)
Since init_hdr_offset is an unsigned 32-bit integer, this condition can
never be true and triggers a Smatch warning:
warn: unsigned 'init_hdr_offset' is never less than zero
In addition, the subsequent bounds check: if ((init_hdr_offset +
init_hdr_size) > vram_size) was vulnerable to integer overflow when
adding the two unsigned values. Thus, by promoting offset and size to
64-bit and using check_add_overflow() to safely validate the sum against
VRAM size.
Fixes: a5d4d72eee03 ("drm/amdgpu: Introduce SRIOV critical regions v2 during VF
init")
Reported by: Dan Carpenter <[email protected]>
Cc: Ellen Pan <[email protected]>
Cc: Christian König <[email protected]>
Cc: Alex Deucher <[email protected]>
Signed-off-by: Srinivasan Shanmugam <[email protected]>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
index 66e9cd103597..45f2ad083338 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
@@ -937,9 +937,10 @@ static uint8_t
amdgpu_virt_crit_region_calc_checksum(uint8_t *buf_start, uint8_t
int amdgpu_virt_init_critical_region(struct amdgpu_device *adev)
{
struct amd_sriov_msg_init_data_header *init_data_hdr = NULL;
- uint32_t init_hdr_offset = adev->virt.init_data_header.offset;
- uint32_t init_hdr_size = adev->virt.init_data_header.size_kb << 10;
- uint64_t vram_size;
+ u64 init_hdr_offset = adev->virt.init_data_header.offset;
+ u64 init_hdr_size = (u64)adev->virt.init_data_header.size_kb << 10; /*
KB → bytes */
+ u64 vram_size;
+ u64 end;
int r = 0;
uint8_t checksum = 0;
@@ -957,7 +958,7 @@ int amdgpu_virt_init_critical_region(struct amdgpu_device
*adev)
return -EINVAL;
vram_size <<= 20;
- if ((init_hdr_offset + init_hdr_size) > vram_size) {
+ if (check_add_overflow(init_hdr_offset, init_hdr_size, &end) || end >
vram_size) {
dev_err(adev->dev, "init_data_header exceeds VRAM size,
exiting\n");
return -EINVAL;
}
--
2.34.1
