diff mbox series

[4.19,45/65] drm/amd/amdgpu: Fix GPR read from debugfs (v2)

Message ID 20200324130802.708594637@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg KH March 24, 2020, 1:11 p.m. UTC 
From: Tom St Denis <tom.stdenis@amd.com>

commit 5bbc6604a62814511c32f2e39bc9ffb2c1b92cbe 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>

---
 drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
diff mbox series

Patch

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c
@@ -694,11 +694,11 @@  static ssize_t amdgpu_debugfs_gpr_read(s
 	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(s
 	while (size) {
 		uint32_t value;
 
-		value = data[offset++];
+		value = data[result >> 2];
 		r = put_user(value, (uint32_t *)buf);
 		if (r) {
 			result = r;