46d98eb4e1
The commoncap implementation of the bprm_secureexec hook is the only LSM that depends on the final call to its bprm_set_creds hook (since it may be called for multiple files, it ignores bprm->called_set_creds). As a result, it cannot safely _clear_ bprm->secureexec since other LSMs may have set it. Instead, remove the bprm_secureexec hook by introducing a new flag to bprm specific to commoncap: cap_elevated. This is similar to cap_effective, but that is used for a specific subset of elevated privileges, and exists solely to track state from bprm_set_creds to bprm_secureexec. As such, it will be removed in the next patch. Here, set the new bprm->cap_elevated flag when setuid/setgid has happened from bprm_fill_uid() or fscapabilities have been prepared. This temporarily moves the bprm_secureexec hook to a static inline. The helper will be removed in the next patch; this makes the step easier to review and bisect, since this does not introduce any changes to inputs nor outputs to the "elevated privileges" calculation. The new flag is merged with the bprm->secureexec flag in setup_new_exec() since this marks the end of any further prepare_binprm() calls. Cc: Andy Lutomirski <luto@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Andy Lutomirski <luto@kernel.org> Acked-by: James Morris <james.l.morris@oracle.com> Acked-by: Serge Hallyn <serge@hallyn.com> |
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| .. | ||
| apparmor | ||
| integrity | ||
| keys | ||
| loadpin | ||
| selinux | ||
| smack | ||
| tomoyo | ||
| yama | ||
| commoncap.c | ||
| device_cgroup.c | ||
| inode.c | ||
| Kconfig | ||
| lsm_audit.c | ||
| Makefile | ||
| min_addr.c | ||
| security.c | ||