深刻なセキュリティ：Linuxカーネルのバグが15年後に表面化した

12 GRIMM Linux. , 15 . , , ; , , . CVE .

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• CVE-2021-27365. - sprintf().

  
  
  
  
  

• CVE-2021-27363. - ID. 

  
  
  
  
  

• CVE-2021-27364. , .

  
  
  
  
  

iSCSI: , SCSI : SCSI, , .

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, , , (, , ) Linux lib/modules



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: , Linux, 7 2021 : 5.11.4, 5.10.21, 5.4.103, 4.19.179, 4.1.4.224, 4.9.260, 4.4.260. , , , . , uname -r

Linux 4500 :

   root@slack:/lib/modules/5.10.23# find . -name '*.ko'
   ./kernel/arch/x86/crypto/aegis128-aesni.ko
   ./kernel/arch/x86/crypto/blake2s-x86_64.ko
   ./kernel/arch/x86/crypto/blowfish-x86_64.ko
   [...4472 lines deleted...]
   ./kernel/sound/usb/usx2y/snd-usb-usx2y.ko
   ./kernel/sound/x86/snd-hdmi-lpe-audio.ko
   ./kernel/virt/lib/irqbypass.ko  
   #
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

, Tascam Ux2y (, US122, US224, US428), , , - snd-usb-usx2y.ko



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, sprintf()



. , formatted print into string – , , . :

   char buf[64];      /* Reserve a 64-byte block of bytes           */
   char *str = "42";  /* Actually has 3 bytes, thus: '4'  '2'  NUL  */
                      /* Trailing zero auto-added:   0x34 0x32 0x00 */
   sprintf(buf,"Answer is %s",str)
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

buf, 12 "Answer is 42", ASCII NUL, 64- – 51 .

sprintf()



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54 , , "Answer is" buf..

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KASLR, kernel address space layout randomisation ( ), , .

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• , . Linux kernel.modules_disable=1
  
  
  
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  sysctl -w kernel.modules_disable=1
  
  echo 1 > /proc/sys/kernel/modules_disable
        
        
  
          
          
          
        
  
      
          
          
          
        
        
  
          
          
          
        
  
      
      

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