drm/amdgpu: Fix a bug for input with double sscanf

Remove double-sscanf to scan for %llu and 0x%llx,
as that is not going to work!

The %llu will consume the "0" in "0x" of your
input, and the hex value you think you're entering
will always be 0. That is, a valid hex value can
never be consumed.

On the other hand, just entering a hex number
without leading 0x will either be scanned as a
string and not match, for instance FAB123, or
the leading decimal portion is scanned as the
%llu, for instance 123FAB will be scanned as 123,
which is not correct.

Thus remove the first %llu scan and leave only the
%llx scan, removing the leading 0x since %llx can
scan either.

Addresses are usually always hex values, so this
suffices.

Cc: Alexander Deucher <Alexander.Deucher@amd.com>
Cc: Xinhui Pan <xinhui.pan@amd.com>
Cc: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Luben Tuikov <luben.tuikov@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
index 0541196..9041453 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
@@ -230,9 +230,8 @@ static int amdgpu_ras_debugfs_ctrl_parse_data(struct file *f,
        if (op != -1) {
 
                if (op == 3) {
-                       if (sscanf(str, "%*s %llu", &address) != 1)
-                               if (sscanf(str, "%*s 0x%llx", &address) != 1)
-                                       return -EINVAL;
+                       if (sscanf(str, "%*s %llx", &address) != 1)
+                               return -EINVAL;
 
                        data->op = op;
                        data->inject.address = address;
@@ -255,11 +254,9 @@ static int amdgpu_ras_debugfs_ctrl_parse_data(struct file *f,
                data->op = op;
 
                if (op == 2) {
-                       if (sscanf(str, "%*s %*s %*s %u %llu %llu",
-                                               &sub_block, &address, &value) != 3)
-                               if (sscanf(str, "%*s %*s %*s 0x%x 0x%llx 0x%llx",
-                                                       &sub_block, &address, &value) != 3)
-                                       return -EINVAL;
+                       if (sscanf(str, "%*s %*s %*s %x %llx %llx",
+                                  &sub_block, &address, &value) != 3)
+                               return -EINVAL;
                        data->head.sub_block_index = sub_block;
                        data->inject.address = address;
                        data->inject.value = value;