如何辨别你的 SD 卡是否是假的

Question 1

直接打开卡设备，写入0x00标签上的容量。写入0x55 0xff 0xaa前三个字节，并查找任何非0x00标签容量的非字节。如果找到一个，则该卡是假的或有缺陷的。如果找到0x55 0xff 0xaa...肯定是假的。

dd if=/dev/zero of=/dev/mmcblkX bs=16M count=...
echo -e -n '\x55\xff\xaa' > /dev/mmcblkX
hexdump /dev/mmcblkX

Answer

直接打开卡设备，写入0x00标签上的容量。写入0x55 0xff 0xaa前三个字节，并查找任何非0x00标签容量的非字节。如果找到一个，则该卡是假的或有缺陷的。如果找到0x55 0xff 0xaa...肯定是假的。

dd if=/dev/zero of=/dev/mmcblkX bs=16M count=...
echo -e -n '\x55\xff\xaa' > /dev/mmcblkX
hexdump /dev/mmcblkX

Question 2

我相信这也值得一提，它是 h2testw:f3 的替代品。

文档位于：

https://fight-flash-fraud.readthedocs.io/en/stable/

在我的系统上：

$ sudo apt-get install f3

最基本的用法很简单：

$ sudo f3probe --destructive --time-ops /dev/mmcblk0

或者

$ sudo f3probe --destructive --time-ops /dev/sdb

取决于您的系统如何看待 SD 卡读取器（使用lsblk有疑问）。

在我的系统上报告：

F3 probe 6.0
Copyright (C) 2010 Digirati Internet LTDA.
This is free software; see the source for copying conditions.

WARNING: Probing normally takes from a few seconds to 15 minutes, but
it can take longer. Please be patient.

Bad news: The device `/dev/sdb' is a counterfeit of type limbo

You can "fix" this device using the following command:
f3fix --last-sec=7860034 /dev/sdb

Device geometry:
*Usable* size: 3.75 GB (7860035 blocks)
Announced size: 15.62 GB (32768000 blocks)
Module: 16.00 GB (2^34 Bytes)
Approximate cache size: 1.00 MB (2048 blocks), need-reset=no
Physical block size: 512.00 Byte (2^9 Bytes)

Probe time: 1'11"
Operation: total time / count = avg time
Read: 336.9ms / 4260 = 79us
Write: 1'10" / 57554 = 1.2ms
Reset: 164.9ms / 1 = 164.9ms

如果您不能使用f3probe，则必须使用传统方法（f3write后跟f3read）：

$ f3write /media/malat/NEW\ VOLUME
Free space: 15.61 GB
Creating file 1.h2w ... OK!
Creating file 2.h2w ... OK!
Creating file 3.h2w ... OK!
Creating file 4.h2w ... OK!
Creating file 5.h2w ... OK!
Creating file 6.h2w ... OK!
Creating file 7.h2w ... OK!
Creating file 8.h2w ... OK!
Creating file 9.h2w ... OK!
Creating file 10.h2w ... OK!
Creating file 11.h2w ... OK!
Creating file 12.h2w ... OK!
Creating file 13.h2w ... OK!
Creating file 14.h2w ... OK!
Creating file 15.h2w ... OK!
Creating file 16.h2w ... OK!
Free space: 0.00 Byte
Average writing speed: 8.48 MB/s

$ f3read /media/malat/NEW\ VOLUME
                  SECTORS      ok/corrupted/changed/overwritten
Validating file 1.h2w ... 2097152/        0/      0/      0
Validating file 2.h2w ... 2097152/        0/      0/      0
Validating file 3.h2w ... 2097152/        0/      0/      0
Validating file 4.h2w ... 1533687/   563465/      0/      0
Validating file 5.h2w ...       0/  2097152/      0/      0
Validating file 6.h2w ...       0/  2097152/      0/      0
Validating file 7.h2w ...       0/  2097152/      0/      0
Validating file 8.h2w ...       0/  2097152/      0/      0
Validating file 9.h2w ...       0/  2097152/      0/      0
Validating file 10.h2w ...       0/  2097152/      0/      0
Validating file 11.h2w ...       0/  2097152/      0/      0
Validating file 12.h2w ...       0/  2097152/      0/      0
Validating file 13.h2w ...       0/  2097152/      0/      0
Validating file 14.h2w ...       0/  2097152/      0/      0
Validating file 15.h2w ...       0/  2097152/      0/      0
Validating file 16.h2w ...      16/  1273792/      0/      0

  Data OK: 3.73 GB (7825159 sectors)
Data LOST: 11.88 GB (24905929 sectors)
      Corrupted: 11.88 GB (24905929 sectors)
Slightly changed: 0.00 Byte (0 sectors)
    Overwritten: 0.00 Byte (0 sectors)
Average reading speed: 3.20 MB/s

Answer