kernel/linux.git/include/linux/security.h, branch v4.19.283

binder: use cred instead of task for selinux checks

2021-11-26T10:35:56+00:00

commit 52f88693378a58094c538662ba652aff0253c4fe upstream. Since binder was integrated with selinux, it has passed 'struct task_struct' associated with the binder_proc to represent the source and target of transactions. The conversion of task to SID was then done in the hook implementations. It turns out that there are race conditions which can result in an incorrect security context being used. Fix by using the 'struct cred' saved during binder_open and pass it to the selinux subsystem. Cc: stable@vger.kernel.org # 5.14 (need backport for earlier stables) Fixes: 79af73079d75 ("Add security hooks to binder and implement the hooks for SELinux.") Suggested-by: Jann Horn Signed-off-by: Todd Kjos Acked-by: Casey Schaufler Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman

fix namespaced fscaps when !CONFIG_SECURITY

2020-12-30T10:26:06+00:00

[ Upstream commit ed9b25d1970a4787ac6a39c2091e63b127ecbfc1 ] Namespaced file capabilities were introduced in 8db6c34f1dbc . When userspace reads an xattr for a namespaced capability, a virtualized representation of it is returned if the caller is in a user namespace owned by the capability's owning rootid. The function which performs this virtualization was not hooked up if CONFIG_SECURITY=n. Therefore in that case the original xattr was shown instead of the virtualized one. To test this using libcap-bin (*1), $ v=$(mktemp) $ unshare -Ur setcap cap_sys_admin-eip $v $ unshare -Ur setcap -v cap_sys_admin-eip $v /tmp/tmp.lSiIFRvt8Y: OK "setcap -v" verifies the values instead of setting them, and will check whether the rootid value is set. Therefore, with this bug un-fixed, and with CONFIG_SECURITY=n, setcap -v will fail: $ v=$(mktemp) $ unshare -Ur setcap cap_sys_admin=eip $v $ unshare -Ur setcap -v cap_sys_admin=eip $v nsowner[got=1000, want=0],/tmp/tmp.HHDiOOl9fY differs in [] Fix this bug by calling cap_inode_getsecurity() in security_inode_getsecurity() instead of returning -EOPNOTSUPP, when CONFIG_SECURITY=n. *1 - note, if libcap is too old for getcap to have the '-n' option, then use verify-caps instead. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=209689 Cc: Hervé Guillemet Acked-by: Casey Schaufler Signed-off-by: Serge Hallyn Signed-off-by: Andrew G. Morgan Signed-off-by: James Morris Signed-off-by: Sasha Levin

LSM: generalize flag passing to security_capable

2020-01-23T07:21:29+00:00

[ Upstream commit c1a85a00ea66cb6f0bd0f14e47c28c2b0999799f ] This patch provides a general mechanism for passing flags to the security_capable LSM hook. It replaces the specific 'audit' flag that is used to tell security_capable whether it should log an audit message for the given capability check. The reason for generalizing this flag passing is so we can add an additional flag that signifies whether security_capable is being called by a setid syscall (which is needed by the proposed SafeSetID LSM). Signed-off-by: Micah Morton Reviewed-by: Kees Cook Signed-off-by: James Morris Signed-off-by: Sasha Levin

Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

2018-08-15T17:25:26+00:00

Pull security subsystem updates from James Morris: - kstrdup() return value fix from Eric Biggers - Add new security_load_data hook to differentiate security checking of kernel-loaded binaries in the case of there being no associated file descriptor, from Mimi Zohar. - Add ability to IMA to specify a policy at build-time, rather than just via command line params or by loading a custom policy, from Mimi. - Allow IMA and LSMs to prevent sysfs firmware load fallback (e.g. if using signed firmware), from Mimi. - Allow IMA to deny loading of kexec kernel images, as they cannot be measured by IMA, from Mimi. * 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: security: check for kstrdup() failure in lsm_append() security: export security_kernel_load_data function ima: based on policy warn about loading firmware (pre-allocated buffer) module: replace the existing LSM hook in init_module ima: add build time policy ima: based on policy require signed firmware (sysfs fallback) firmware: add call to LSM hook before firmware sysfs fallback ima: based on policy require signed kexec kernel images kexec: add call to LSM hook in original kexec_load syscall security: define new LSM hook named security_kernel_load_data MAINTAINERS: remove the outdated "LINUX SECURITY MODULE (LSM) FRAMEWORK" entry

security: define new LSM hook named security_kernel_load_data

2018-07-16T19:31:57+00:00

Differentiate between the kernel reading a file specified by userspace from the kernel loading a buffer containing data provided by userspace. This patch defines a new LSM hook named security_kernel_load_data(). Signed-off-by: Mimi Zohar Cc: Eric Biederman Cc: Luis R. Rodriguez Cc: Kees Cook Cc: Casey Schaufler Acked-by: Serge Hallyn Acked-by: Kees Cook Signed-off-by: James Morris

security_file_open(): lose cred argument

2018-07-12T14:04:15+00:00

Acked-by: Linus Torvalds Signed-off-by: Al Viro

security: add hook for socketpair()

2018-05-04T19:48:54+00:00

Right now the LSM labels for socketpairs are always uninitialized, since there is no security hook for the socketpair() syscall. This patch adds the required hooks so LSMs can properly label socketpairs. This allows SO_PEERSEC to return useful information on those sockets. Note that the behavior of socketpair() can be emulated by creating a listener socket, connecting to it, and then discarding the initial listener socket. With this workaround, SO_PEERSEC would return the caller's security context. However, with socketpair(), the uninitialized context is returned unconditionally. This is unexpected and makes socketpair() less useful in situations where the security context is crucial to the application. With the new socketpair-hook this disparity can be solved by making socketpair() return the expected security context. Acked-by: Serge Hallyn Signed-off-by: Tom Gundersen Signed-off-by: David Herrmann Signed-off-by: James Morris

Merge tag 'v4.17-rc2' into next-general

2018-04-23T17:57:26+00:00

Sync to Linux 4.17-rc2 for developers.

security: remove security_settime

2018-04-17T05:18:48+00:00

security_settime was a wrapper around security_settime64. There are no more users of it. Therefore it can be removed. It was removed in: commit 4eb1bca17933 ("time: Use do_settimeofday64() internally") Signed-off-by: Sargun Dhillon Signed-off-by: James Morris

Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

2018-04-07T23:53:59+00:00

Pull integrity updates from James Morris: "A mixture of bug fixes, code cleanup, and continues to close IMA-measurement, IMA-appraisal, and IMA-audit gaps. Also note the addition of a new cred_getsecid LSM hook by Matthew Garrett: For IMA purposes, we want to be able to obtain the prepared secid in the bprm structure before the credentials are committed. Add a cred_getsecid hook that makes this possible. which is used by a new CREDS_CHECK target in IMA: In ima_bprm_check(), check with both the existing process credentials and the credentials that will be committed when the new process is started. This will not change behaviour unless the system policy is extended to include CREDS_CHECK targets - BPRM_CHECK will continue to check the same credentials that it did previously" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: ima: Fallback to the builtin hash algorithm ima: Add smackfs to the default appraise/measure list evm: check for remount ro in progress before writing ima: Improvements in ima_appraise_measurement() ima: Simplify ima_eventsig_init() integrity: Remove unused macro IMA_ACTION_RULE_FLAGS ima: drop vla in ima_audit_measurement() ima: Fix Kconfig to select TPM 2.0 CRB interface evm: Constify *integrity_status_msg[] evm: Move evm_hmac and evm_hash from evm_main.c to evm_crypto.c fuse: define the filesystem as untrusted ima: fail signature verification based on policy ima: clear IMA_HASH ima: re-evaluate files on privileged mounted filesystems ima: fail file signature verification on non-init mounted filesystems IMA: Support using new creds in appraisal policy security: Add a cred_getsecid hook