17f60a7da1
There is no way to limit the capabilities of usermodehelpers. This problem reared its head recently when someone complained that any user with cap_net_admin was able to load arbitrary kernel modules, even though the user didn't have cap_sys_module. The reason is because the actual load is done by a usermode helper and those always have the full cap set. This patch addes new sysctls which allow us to bound the permissions of usermode helpers. /proc/sys/kernel/usermodehelper/bset /proc/sys/kernel/usermodehelper/inheritable You must have CAP_SYS_MODULE and CAP_SETPCAP to change these (changes are &= ONLY). When the kernel launches a usermodehelper it will do so with these as the bset and pI. -v2: make globals static create spinlock to protect globals -v3: require both CAP_SETPCAP and CAP_SYS_MODULE -v4: fix the typo s/CAP_SET_PCAP/CAP_SETPCAP/ because I didn't commit Signed-off-by: Eric Paris <eparis@redhat.com> No-objection-from: Serge E. Hallyn <serge.hallyn@canonical.com> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com> Acked-by: Andrew G. Morgan <morgan@kernel.org> Signed-off-by: James Morris <jmorris@namei.org> |
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| crypto | ||
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| keys | ||
| linux | ||
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| media | ||
| mtd | ||
| net | ||
| pcmcia | ||
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| rxrpc | ||
| scsi | ||
| sound | ||
| staging | ||
| target | ||
| trace | ||
| video | ||
| xen | ||
| Kbuild | ||