Add /usr/sbin and /sbin to default root PATH When dropbear is used in a very restricted environment (such as in a initrd), the default user shell is often also very restricted and doesn't take care of setting the PATH so the user ends up with the PATH set by dropbear. Unfortunately, dropbear always sets "/usr/bin:/bin" as default PATH even for the root user which should have /usr/sbin and /sbin too. For a concrete instance of this problem, see the "Remote Unlocking" section in this tutorial: https://paxswill.com/blog/2013/11/04/encrypted-raspberry-pi/ It speaks of a bug in the initramfs script because it's written "blkid" instead of "/sbin/blkid"... this is just because the scripts from the initramfs do not expect to have a PATH without the sbin directories and because dropbear is not setting the PATH appropriately for the root user. I'm thus suggesting to use the attached patch to fix this misbehaviour (I did not test it, but it's easy enough). It might seem anecdotic but multiple Kali users have been bitten by this. From https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=903403

/* LibTomCrypt, modular cryptographic library -- Tom St Denis
 *
 * LibTomCrypt is a library that provides various cryptographic
 * algorithms in a highly modular and flexible manner.
 *
 * The library is free for all purposes without any express
 * guarantee it works.
 */
#include "tomcrypt.h"

/**
   @file lrw_getiv.c
   LRW_MODE implementation, Retrieve the current IV, Tom St Denis
*/

#ifdef LTC_LRW_MODE

/**
  Get the IV for LRW
  @param IV      [out] The IV, must be 16 octets
  @param len     Length ... must be at least 16 :-)
  @param lrw     The LRW state to read
  @return CRYPT_OK if successful
*/
int lrw_getiv(unsigned char *IV, unsigned long *len, symmetric_LRW *lrw)
{
   LTC_ARGCHK(IV != NULL);
   LTC_ARGCHK(len != NULL);
   LTC_ARGCHK(lrw != NULL);
   if (*len < 16) {
       *len = 16;
       return CRYPT_BUFFER_OVERFLOW;
   }

   XMEMCPY(IV, lrw->IV, 16);
   *len = 16;
   return CRYPT_OK;
}

#endif
/* ref:         $Format:%D$ */
/* git commit:  $Format:%H$ */
/* commit time: $Format:%ai$ */