drm/amd/amdgpu: Fix GPR read from debugfs (v2)

commit 5bbc6604a6 upstream.

The offset into the array was specified in bytes but should
be in terms of 32-bit words.  Also prevent large reads that
would also cause a buffer overread.

v2:  Read from correct offset from internal storage buffer.

Signed-off-by: Tom St Denis <tom.stdenis@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Tom St Denis 2020-03-10 08:40:41 -04:00 committed by Greg Kroah-Hartman
parent 221ab6a9e6
commit 053a9862f0

View file

@ -694,11 +694,11 @@ static ssize_t amdgpu_debugfs_gpr_read(struct file *f, char __user *buf,
ssize_t result = 0;
uint32_t offset, se, sh, cu, wave, simd, thread, bank, *data;
if (size & 3 || *pos & 3)
if (size > 4096 || size & 3 || *pos & 3)
return -EINVAL;
/* decode offset */
offset = *pos & GENMASK_ULL(11, 0);
offset = (*pos & GENMASK_ULL(11, 0)) >> 2;
se = (*pos & GENMASK_ULL(19, 12)) >> 12;
sh = (*pos & GENMASK_ULL(27, 20)) >> 20;
cu = (*pos & GENMASK_ULL(35, 28)) >> 28;
@ -729,7 +729,7 @@ static ssize_t amdgpu_debugfs_gpr_read(struct file *f, char __user *buf,
while (size) {
uint32_t value;
value = data[offset++];
value = data[result >> 2];
r = put_user(value, (uint32_t *)buf);
if (r) {
result = r;