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Sargun Dhillon sargun

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sargun / hostname2.md
Created August 27, 2021 03:45 
sargun@ubuntu:~$ hostname foo
hostname: you must be root to change the host name
@sargun
sargun / unshare.md
Created August 27, 2021 03:44 
sargun@ubuntu:~$ unshare -U --map-root-user
root@ubuntu:~# id
uid=0(root) gid=0(root) groups=0(root),65534(nogroup)
root@ubuntu:~# cat /proc/self/status |grep Cap
CapInh:	0000000000000000
CapPrm:	000001ffffffffff
CapEff:	000001ffffffffff
CapBnd:	000001ffffffffff
CapAmb:	0000000000000000
@sargun
sargun / hostname.md
Created August 27, 2021 03:44 
sargun@ubuntu:~$ getcap $(which ping)
/bin/ping = cap_net_raw+ep
@sargun
sargun / hostname.md
Created August 27, 2021 03:43 
sargun@ubuntu:~$ hostname foo
hostname: you must be root to change the host name
@sargun
sargun / cap.md
Created August 27, 2021 03:42 
sargun@ubuntu:~$ cat /proc/self/status |grep Cap
CapInh:	0000000000000000
CapPrm:	0000000000000000
CapEff:	0000000000000000
CapBnd:	000001ffffffffff
CapAmb:	0000000000000000
@sargun
sargun / test.console
Created August 27, 2021 03:42
sargun@ubuntu:~$ unshare -U --map-root-user
root@ubuntu:~# id
uid=0(root) gid=0(root) groups=0(root),65534(nogroup)
root@ubuntu:~# cat /proc/self/status |grep Cap
CapInh: 0000000000000000
CapPrm: 000001ffffffffff
CapEff: 000001ffffffffff
CapBnd: 000001ffffffffff
CapAmb: 0000000000000000
@sargun
sargun / test.md
Created August 27, 2021 03:42 
sargun@ubuntu:~$ unshare -U --map-root-user
root@ubuntu:~# id
uid=0(root) gid=0(root) groups=0(root),65534(nogroup)
root@ubuntu:~# cat /proc/self/status |grep Cap
CapInh:	0000000000000000
CapPrm:	000001ffffffffff
CapEff:	000001ffffffffff
CapBnd:	000001ffffffffff
CapAmb:	0000000000000000
@sargun
sargun / utsname.h
Created August 27, 2021 03:21
struct uts_namespace {
struct kref kref;
struct new_utsname name;
struct user_namespace *user_ns;
struct ucounts *ucounts;
struct ns_common ns;
} __randomize_layout;
@sargun
sargun / capability.c
Created August 27, 2021 03:20
/**
* capable - Determine if the current task has a superior capability in effect
* @cap: The capability to be tested for
*
* Return true if the current task has the given superior capability currently
* available for use, false if not.
*
* This sets PF_SUPERPRIV on the task if the capability is available on the
* assumption that it's about to be used.
*/
@sargun
sargun / trusted_tpm1.c
Created August 27, 2021 03:07
/*
* Lock a trusted key, by extending a selected PCR.
*
* Prevents a trusted key that is sealed to PCRs from being accessed.
* This uses the tpm driver's extend function.
*/
static int pcrlock(const int pcrnum)
{
if (!capable(CAP_SYS_ADMIN))
return -EPERM;