Ubuntu下U盘变成只读解决方法

1. 首先执行：tail -f /var/log/syslog然后插入U盘会打印如下信息：

Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21454.853155] usb 1-8: new high-speed USB device number 16 using xhci_hcd
Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21455.004258] usb 1-8: New USB device found, idVendor=0930, idProduct=6544
Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21455.004263] usb 1-8: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21455.004267] usb 1-8: Product: TransMemory     
Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21455.004271] usb 1-8: Manufacturer: TOSHIBA
Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21455.004274] usb 1-8: SerialNumber: C412F52D6C99C2210002A066
Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21455.005307] usb-storage 1-8:1.0: USB Mass Storage device detected
Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21455.006813] scsi host5: usb-storage 1-8:1.0
Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy mtp-probe: checking bus 1, device 16: "/sys/devices/pci0000:00/0000:00:14.0/usb1/1-8"
Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy mtp-probe: bus: 1, device: 16 was not an MTP device
Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy upowerd[1030]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-8/1-8:1.0
Aug  3 15:37:39 miaojunchen-HP-280-Pro-G2-MT-Legacy upowerd[1030]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:14.0/usb1/1-8
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.049539] scsi 5:0:0:0: Direct-Access     TOSHIBA  TransMemory      1.00 PQ: 0 ANSI: 4
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.050214] sd 5:0:0:0: Attached scsi generic sg1 type 0
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.050365] sd 5:0:0:0: [sdc] 30310400 512-byte logical blocks: (15.5 GB/14.5 GiB)
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.050595] sd 5:0:0:0: [sdc] Write Protect is off
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.050600] sd 5:0:0:0: [sdc] Mode Sense: 45 00 00 00
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.050803] sd 5:0:0:0: [sdc] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.052425]  sdc: sdc1
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.053771] sd 5:0:0:0: [sdc] Attached SCSI removable disk
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.447932] FAT-fs (sdc1): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy systemd[1]: Started Clean the /media/miaojunchen/TOSHIBA mount point.
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy udisksd[853]: Mounted /dev/sdc1 at /media/miaojunchen/TOSHIBA on behalf of uid 1000
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy dbus-daemon[1702]: [session uid=1000 pid=1702] Activating service name='org.gnome.Shell.HotplugSniffer' requested by ':1.15' (uid=1000 pid=1857 comm="/usr/bin/gnome-shell " label="unconfined")
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy dbus-daemon[1702]: [session uid=1000 pid=1702] Successfully activated service 'org.gnome.Shell.HotplugSniffer'
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.667176] FAT-fs (sdc1): error, corrupted directory (invalid entries)
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.667179] FAT-fs (sdc1): Filesystem has been set read-only
Aug  3 15:37:41 miaojunchen-HP-280-Pro-G2-MT-Legacy kernel: [21456.667223] FAT-fs (sdc1): error, corrupted directory (invalid entries)
Aug  3 15:39:21 miaojunchen-HP-280-Pro-G2-MT-Legacy shutter.desktop[8360]: e2::Wnck::Screen=HASH(0x55618da13660)
Aug  3 15:39:21 miaojunchen-HP-280-Pro-G2-MT-Legacy shutter.desktop[8360]: fct_update_tray_menu was called by Gnome2::Wnck::Screen=HASH(0x55618da13660)
Aug  3 15:39:21 miaojunchen-HP-280-Pro-G2-MT-Legacy shutter.desktop[8360]: message repeated 103 times: [ fct_update_tray_menu was called by Gnome2::Wnck::Screen=HASH(0x55618da13660)]
Aug  3 15:39:26 miaojunchen-HP-280-Pro-G2-MT-Legacy udisksd[853]: Cleaning up mount point /media/miaojunchen/TOSHIBA (device 8:33 is not mounted)
Aug  3 15:39:26 miaojunchen-HP-280-Pro-G2-MT-Legacy systemd[1]: Stopping Clean the /media/miaojunchen/TOSHIBA mount point...
Aug  3 15:39:26 miaojunchen-HP-280-Pro-G2-MT-Legacy systemd[1]: Stopped Clean the /media/miaojunchen/TOSHIBA mount point.
Aug  3 15:39:26 miaojunchen-HP-280-Pro-G2-MT-Legacy udisksd[853]: Unmounted /dev/sdc1 on behalf of uid 1000
Aug  3 15:40:27 miaojunchen-HP-280-Pro-G2-MT-Legacy systemd[1]: Started Clean the /media/miaojunchen/TOSHIBA mount point.

日志红色部分就是我们所需要的信息：

2.umount /media/miaojunchen/TOSHIBA

3. sudo dosfsck -v -a /dev/sdc1

通过以上步骤，U盘可以读写和删除数据了