diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-14 01:38:53 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-14 01:38:53 +0300 |
commit | 80a17a5f501ea048d86f81d629c94062b76610d4 (patch) | |
tree | 55dd0a1490d1e6631ca319a1205f974f041b494f /security/apparmor/lsm.c | |
parent | edda415314804c29fa07e538938fa07947012d8f (diff) | |
parent | 588558eb6d0e0b6edfa65a67e906c2ffeba63ff1 (diff) | |
download | linux-80a17a5f501ea048d86f81d629c94062b76610d4.tar.xz |
Merge tag 'apparmor-pr-2018-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor
Pull apparmor updates from John Johansen:
"Features:
- add base infrastructure for socket mediation. ABI bump and
additional checks to ensure only v8 compliant policy uses socket af
mediation.
- improve and cleanup dfa verification
- improve profile attachment logic
- improve overlapping expression handling
- add the xattr matching to the attachment logic
- improve signal mediation handling with stacked labels
- improve handling of no_new_privs in a label stack
Cleanups and changes:
- use dfa to parse string split
- bounded version of label_parse
- proper line wrap nulldfa.in
- split context out into task and cred naming to better match usage
- simplify code in aafs
Bug fixes:
- fix display of .ns_name for containers
- fix resource audit messages when auditing peer
- fix logging of the existence test for signals
- fix resource audit messages when auditing peer
- fix display of .ns_name for containers
- fix an error code in verify_table_headers()
- fix memory leak on buffer on error exit path
- fix error returns checks by making size a ssize_t"
* tag 'apparmor-pr-2018-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: (36 commits)
apparmor: fix memory leak on buffer on error exit path
apparmor: fix dangling symlinks to policy rawdata after replacement
apparmor: Fix an error code in verify_table_headers()
apparmor: fix error returns checks by making size a ssize_t
apparmor: update MAINTAINERS file git and wiki locations
apparmor: remove POLICY_MEDIATES_SAFE
apparmor: add base infastructure for socket mediation
apparmor: improve overlapping domain attachment resolution
apparmor: convert attaching profiles via xattrs to use dfa matching
apparmor: Add support for attaching profiles via xattr, presence and value
apparmor: cleanup: simplify code to get ns symlink name
apparmor: cleanup create_aafs() error path
apparmor: dfa split verification of table headers
apparmor: dfa add support for state differential encoding
apparmor: dfa move character match into a macro
apparmor: update domain transitions that are subsets of confinement at nnp
apparmor: move context.h to cred.h
apparmor: move task related defines and fns to task.X files
apparmor: cleanup, drop unused fn __aa_task_is_confined()
apparmor: cleanup fixup description of aa_replace_profiles
...
Diffstat (limited to 'security/apparmor/lsm.c')
-rw-r--r-- | security/apparmor/lsm.c | 467 |
1 files changed, 434 insertions, 33 deletions
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index 528f59b580a8..ce2b89e9ad94 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -29,9 +29,10 @@ #include "include/apparmorfs.h" #include "include/audit.h" #include "include/capability.h" -#include "include/context.h" +#include "include/cred.h" #include "include/file.h" #include "include/ipc.h" +#include "include/net.h" #include "include/path.h" #include "include/label.h" #include "include/policy.h" @@ -50,12 +51,12 @@ DEFINE_PER_CPU(struct aa_buffers, aa_buffers); */ /* - * free the associated aa_task_ctx and put its labels + * put the associated labels */ static void apparmor_cred_free(struct cred *cred) { - aa_free_task_context(cred_ctx(cred)); - cred_ctx(cred) = NULL; + aa_put_label(cred_label(cred)); + cred_label(cred) = NULL; } /* @@ -63,30 +64,17 @@ static void apparmor_cred_free(struct cred *cred) */ static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp) { - /* freed by apparmor_cred_free */ - struct aa_task_ctx *ctx = aa_alloc_task_context(gfp); - - if (!ctx) - return -ENOMEM; - - cred_ctx(cred) = ctx; + cred_label(cred) = NULL; return 0; } /* - * prepare new aa_task_ctx for modification by prepare_cred block + * prepare new cred label for modification by prepare_cred block */ static int apparmor_cred_prepare(struct cred *new, const struct cred *old, gfp_t gfp) { - /* freed by apparmor_cred_free */ - struct aa_task_ctx *ctx = aa_alloc_task_context(gfp); - - if (!ctx) - return -ENOMEM; - - aa_dup_task_context(ctx, cred_ctx(old)); - cred_ctx(new) = ctx; + cred_label(new) = aa_get_newest_label(cred_label(old)); return 0; } @@ -95,10 +83,28 @@ static int apparmor_cred_prepare(struct cred *new, const struct cred *old, */ static void apparmor_cred_transfer(struct cred *new, const struct cred *old) { - const struct aa_task_ctx *old_ctx = cred_ctx(old); - struct aa_task_ctx *new_ctx = cred_ctx(new); + cred_label(new) = aa_get_newest_label(cred_label(old)); +} + +static void apparmor_task_free(struct task_struct *task) +{ + + aa_free_task_ctx(task_ctx(task)); + task_ctx(task) = NULL; +} + +static int apparmor_task_alloc(struct task_struct *task, + unsigned long clone_flags) +{ + struct aa_task_ctx *new = aa_alloc_task_ctx(GFP_KERNEL); + + if (!new) + return -ENOMEM; + + aa_dup_task_ctx(new, task_ctx(current)); + task_ctx(task) = new; - aa_dup_task_context(new_ctx, old_ctx); + return 0; } static int apparmor_ptrace_access_check(struct task_struct *child, @@ -576,11 +582,11 @@ static int apparmor_getprocattr(struct task_struct *task, char *name, int error = -ENOENT; /* released below */ const struct cred *cred = get_task_cred(task); - struct aa_task_ctx *ctx = cred_ctx(cred); + struct aa_task_ctx *ctx = task_ctx(current); struct aa_label *label = NULL; if (strcmp(name, "current") == 0) - label = aa_get_newest_label(ctx->label); + label = aa_get_newest_label(cred_label(cred)); else if (strcmp(name, "prev") == 0 && ctx->previous) label = aa_get_newest_label(ctx->previous); else if (strcmp(name, "exec") == 0 && ctx->onexec) @@ -677,11 +683,11 @@ fail: static void apparmor_bprm_committing_creds(struct linux_binprm *bprm) { struct aa_label *label = aa_current_raw_label(); - struct aa_task_ctx *new_ctx = cred_ctx(bprm->cred); + struct aa_label *new_label = cred_label(bprm->cred); /* bail out if unconfined or not changing profile */ - if ((new_ctx->label->proxy == label->proxy) || - (unconfined(new_ctx->label))) + if ((new_label->proxy == label->proxy) || + (unconfined(new_label))) return; aa_inherit_files(bprm->cred, current->files); @@ -689,7 +695,7 @@ static void apparmor_bprm_committing_creds(struct linux_binprm *bprm) current->pdeath_signal = 0; /* reset soft limits and set hard limits for the new label */ - __aa_transition_rlimits(label, new_ctx->label); + __aa_transition_rlimits(label, new_label); } /** @@ -698,7 +704,9 @@ static void apparmor_bprm_committing_creds(struct linux_binprm *bprm) */ static void apparmor_bprm_committed_creds(struct linux_binprm *bprm) { - /* TODO: cleanup signals - ipc mediation */ + /* clear out temporary/transitional state from the context */ + aa_clear_task_ctx_trans(task_ctx(current)); + return; } @@ -742,6 +750,373 @@ static int apparmor_task_kill(struct task_struct *target, struct siginfo *info, return error; } +/** + * apparmor_sk_alloc_security - allocate and attach the sk_security field + */ +static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags) +{ + struct aa_sk_ctx *ctx; + + ctx = kzalloc(sizeof(*ctx), flags); + if (!ctx) + return -ENOMEM; + + SK_CTX(sk) = ctx; + + return 0; +} + +/** + * apparmor_sk_free_security - free the sk_security field + */ +static void apparmor_sk_free_security(struct sock *sk) +{ + struct aa_sk_ctx *ctx = SK_CTX(sk); + + SK_CTX(sk) = NULL; + aa_put_label(ctx->label); + aa_put_label(ctx->peer); + kfree(ctx); +} + +/** + * apparmor_clone_security - clone the sk_security field + */ +static void apparmor_sk_clone_security(const struct sock *sk, + struct sock *newsk) +{ + struct aa_sk_ctx *ctx = SK_CTX(sk); + struct aa_sk_ctx *new = SK_CTX(newsk); + + new->label = aa_get_label(ctx->label); + new->peer = aa_get_label(ctx->peer); +} + +/** + * apparmor_socket_create - check perms before creating a new socket + */ +static int apparmor_socket_create(int family, int type, int protocol, int kern) +{ + struct aa_label *label; + int error = 0; + + AA_BUG(in_interrupt()); + + label = begin_current_label_crit_section(); + if (!(kern || unconfined(label))) + error = af_select(family, + create_perm(label, family, type, protocol), + aa_af_perm(label, OP_CREATE, AA_MAY_CREATE, + family, type, protocol)); + end_current_label_crit_section(label); + + return error; +} + +/** + * apparmor_socket_post_create - setup the per-socket security struct + * + * Note: + * - kernel sockets currently labeled unconfined but we may want to + * move to a special kernel label + * - socket may not have sk here if created with sock_create_lite or + * sock_alloc. These should be accept cases which will be handled in + * sock_graft. + */ +static int apparmor_socket_post_create(struct socket *sock, int family, + int type, int protocol, int kern) +{ + struct aa_label *label; + + if (kern) { + struct aa_ns *ns = aa_get_current_ns(); + + label = aa_get_label(ns_unconfined(ns)); + aa_put_ns(ns); + } else + label = aa_get_current_label(); + + if (sock->sk) { + struct aa_sk_ctx *ctx = SK_CTX(sock->sk); + + aa_put_label(ctx->label); + ctx->label = aa_get_label(label); + } + aa_put_label(label); + + return 0; +} + +/** + * apparmor_socket_bind - check perms before bind addr to socket + */ +static int apparmor_socket_bind(struct socket *sock, + struct sockaddr *address, int addrlen) +{ + AA_BUG(!sock); + AA_BUG(!sock->sk); + AA_BUG(!address); + AA_BUG(in_interrupt()); + + return af_select(sock->sk->sk_family, + bind_perm(sock, address, addrlen), + aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk)); +} + +/** + * apparmor_socket_connect - check perms before connecting @sock to @address + */ +static int apparmor_socket_connect(struct socket *sock, + struct sockaddr *address, int addrlen) +{ + AA_BUG(!sock); + AA_BUG(!sock->sk); + AA_BUG(!address); + AA_BUG(in_interrupt()); + + return af_select(sock->sk->sk_family, + connect_perm(sock, address, addrlen), + aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk)); +} + +/** + * apparmor_socket_list - check perms before allowing listen + */ +static int apparmor_socket_listen(struct socket *sock, int backlog) +{ + AA_BUG(!sock); + AA_BUG(!sock->sk); + AA_BUG(in_interrupt()); + + return af_select(sock->sk->sk_family, + listen_perm(sock, backlog), + aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk)); +} + +/** + * apparmor_socket_accept - check perms before accepting a new connection. + * + * Note: while @newsock is created and has some information, the accept + * has not been done. + */ +static int apparmor_socket_accept(struct socket *sock, struct socket *newsock) +{ + AA_BUG(!sock); + AA_BUG(!sock->sk); + AA_BUG(!newsock); + AA_BUG(in_interrupt()); + + return af_select(sock->sk->sk_family, + accept_perm(sock, newsock), + aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk)); +} + +static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock, + struct msghdr *msg, int size) +{ + AA_BUG(!sock); + AA_BUG(!sock->sk); + AA_BUG(!msg); + AA_BUG(in_interrupt()); + + return af_select(sock->sk->sk_family, + msg_perm(op, request, sock, msg, size), + aa_sk_perm(op, request, sock->sk)); +} + +/** + * apparmor_socket_sendmsg - check perms before sending msg to another socket + */ +static int apparmor_socket_sendmsg(struct socket *sock, + struct msghdr *msg, int size) +{ + return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size); +} + +/** + * apparmor_socket_recvmsg - check perms before receiving a message + */ +static int apparmor_socket_recvmsg(struct socket *sock, + struct msghdr *msg, int size, int flags) +{ + return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size); +} + +/* revaliation, get/set attr, shutdown */ +static int aa_sock_perm(const char *op, u32 request, struct socket *sock) +{ + AA_BUG(!sock); + AA_BUG(!sock->sk); + AA_BUG(in_interrupt()); + + return af_select(sock->sk->sk_family, + sock_perm(op, request, sock), + aa_sk_perm(op, request, sock->sk)); +} + +/** + * apparmor_socket_getsockname - check perms before getting the local address + */ +static int apparmor_socket_getsockname(struct socket *sock) +{ + return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock); +} + +/** + * apparmor_socket_getpeername - check perms before getting remote address + */ +static int apparmor_socket_getpeername(struct socket *sock) +{ + return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock); +} + +/* revaliation, get/set attr, opt */ +static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock, + int level, int optname) +{ + AA_BUG(!sock); + AA_BUG(!sock->sk); + AA_BUG(in_interrupt()); + + return af_select(sock->sk->sk_family, + opt_perm(op, request, sock, level, optname), + aa_sk_perm(op, request, sock->sk)); +} + +/** + * apparmor_getsockopt - check perms before getting socket options + */ +static int apparmor_socket_getsockopt(struct socket *sock, int level, + int optname) +{ + return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock, + level, optname); +} + +/** + * apparmor_setsockopt - check perms before setting socket options + */ +static int apparmor_socket_setsockopt(struct socket *sock, int level, + int optname) +{ + return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock, + level, optname); +} + +/** + * apparmor_socket_shutdown - check perms before shutting down @sock conn + */ +static int apparmor_socket_shutdown(struct socket *sock, int how) +{ + return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock); +} + +/** + * apparmor_socket_sock_recv_skb - check perms before associating skb to sk + * + * Note: can not sleep may be called with locks held + * + * dont want protocol specific in __skb_recv_datagram() + * to deny an incoming connection socket_sock_rcv_skb() + */ +static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) +{ + return 0; +} + + +static struct aa_label *sk_peer_label(struct sock *sk) +{ + struct aa_sk_ctx *ctx = SK_CTX(sk); + + if (ctx->peer) + return ctx->peer; + + return ERR_PTR(-ENOPROTOOPT); +} + +/** + * apparmor_socket_getpeersec_stream - get security context of peer + * + * Note: for tcp only valid if using ipsec or cipso on lan + */ +static int apparmor_socket_getpeersec_stream(struct socket *sock, + char __user *optval, + int __user *optlen, + unsigned int len) +{ + char *name; + int slen, error = 0; + struct aa_label *label; + struct aa_label *peer; + + label = begin_current_label_crit_section(); + peer = sk_peer_label(sock->sk); + if (IS_ERR(peer)) { + error = PTR_ERR(peer); + goto done; + } + slen = aa_label_asxprint(&name, labels_ns(label), peer, + FLAG_SHOW_MODE | FLAG_VIEW_SUBNS | + FLAG_HIDDEN_UNCONFINED, GFP_KERNEL); + /* don't include terminating \0 in slen, it breaks some apps */ + if (slen < 0) { + error = -ENOMEM; + } else { + if (slen > len) { + error = -ERANGE; + } else if (copy_to_user(optval, name, slen)) { + error = -EFAULT; + goto out; + } + if (put_user(slen, optlen)) + error = -EFAULT; +out: + kfree(name); + + } + +done: + end_current_label_crit_section(label); + + return error; +} + +/** + * apparmor_socket_getpeersec_dgram - get security label of packet + * @sock: the peer socket + * @skb: packet data + * @secid: pointer to where to put the secid of the packet + * + * Sets the netlabel socket state on sk from parent + */ +static int apparmor_socket_getpeersec_dgram(struct socket *sock, + struct sk_buff *skb, u32 *secid) + +{ + /* TODO: requires secid support */ + return -ENOPROTOOPT; +} + +/** + * apparmor_sock_graft - Initialize newly created socket + * @sk: child sock + * @parent: parent socket + * + * Note: could set off of SOCK_CTX(parent) but need to track inode and we can + * just set sk security information off of current creating process label + * Labeling of sk for accept case - probably should be sock based + * instead of task, because of the case where an implicitly labeled + * socket is shared by different tasks. + */ +static void apparmor_sock_graft(struct sock *sk, struct socket *parent) +{ + struct aa_sk_ctx *ctx = SK_CTX(sk); + + if (!ctx->label) + ctx->label = aa_get_current_label(); +} + static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check), LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme), @@ -776,6 +1151,30 @@ static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(getprocattr, apparmor_getprocattr), LSM_HOOK_INIT(setprocattr, apparmor_setprocattr), + LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security), + LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security), + LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security), + + LSM_HOOK_INIT(socket_create, apparmor_socket_create), + LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create), + LSM_HOOK_INIT(socket_bind, apparmor_socket_bind), + LSM_HOOK_INIT(socket_connect, apparmor_socket_connect), + LSM_HOOK_INIT(socket_listen, apparmor_socket_listen), + LSM_HOOK_INIT(socket_accept, apparmor_socket_accept), + LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg), + LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg), + LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname), + LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername), + LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt), + LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt), + LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown), + LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb), + LSM_HOOK_INIT(socket_getpeersec_stream, + apparmor_socket_getpeersec_stream), + LSM_HOOK_INIT(socket_getpeersec_dgram, + apparmor_socket_getpeersec_dgram), + LSM_HOOK_INIT(sock_graft, apparmor_sock_graft), + LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank), LSM_HOOK_INIT(cred_free, apparmor_cred_free), LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare), @@ -785,6 +1184,8 @@ static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds), LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds), + LSM_HOOK_INIT(task_free, apparmor_task_free), + LSM_HOOK_INIT(task_alloc, apparmor_task_alloc), LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit), LSM_HOOK_INIT(task_kill, apparmor_task_kill), }; @@ -1032,12 +1433,12 @@ static int __init set_init_ctx(void) struct cred *cred = (struct cred *)current->real_cred; struct aa_task_ctx *ctx; - ctx = aa_alloc_task_context(GFP_KERNEL); + ctx = aa_alloc_task_ctx(GFP_KERNEL); if (!ctx) return -ENOMEM; - ctx->label = aa_get_label(ns_unconfined(root_ns)); - cred_ctx(cred) = ctx; + cred_label(cred) = aa_get_label(ns_unconfined(root_ns)); + task_ctx(current) = ctx; return 0; } |