commit 09aa4788d6052c6dc423d939319334ebb5d00847 Author: John Johansen Date: Mon Oct 4 15:03:36 2010 -0700 UBUNTU: SAUCE: AppArmor: basic networking rules Base support for network mediation. Signed-off-by: John Johansen diff --git a/security/apparmor/.gitignore b/security/apparmor/.gitignore index 9cdec70..d5b291e 100644 --- a/security/apparmor/.gitignore +++ b/security/apparmor/.gitignore @@ -1,5 +1,6 @@ # # Generated include files # +net_names.h capability_names.h rlim_names.h diff --git a/security/apparmor/Makefile b/security/apparmor/Makefile index d693df8..5dbb72f 100644 --- a/security/apparmor/Makefile +++ b/security/apparmor/Makefile @@ -4,10 +4,10 @@ obj-$(CONFIG_SECURITY_APPARMOR) += apparmor.o apparmor-y := apparmorfs.o audit.o capability.o context.o ipc.o lib.o match.o \ path.o domain.o policy.o policy_unpack.o procattr.o lsm.o \ - resource.o sid.o file.o + resource.o sid.o file.o net.o apparmor-$(CONFIG_SECURITY_APPARMOR_HASH) += crypto.o -clean-files := capability_names.h rlim_names.h +clean-files := capability_names.h rlim_names.h net_names.h # Build a lower case string table of capability names @@ -25,6 +25,38 @@ cmd_make-caps = echo "static const char *const capability_names[] = {" > $@ ;\ -e 's/^\#define[ \t]+CAP_([A-Z0-9_]+)[ \t]+([0-9]+)/\L\1/p' | \ tr '\n' ' ' | sed -e 's/ $$/"\n/' >> $@ +# Build a lower case string table of address family names +# Transform lines from +# define AF_LOCAL 1 /* POSIX name for AF_UNIX */ +# #define AF_INET 2 /* Internet IP Protocol */ +# to +# [1] = "local", +# [2] = "inet", +# +# and build the securityfs entries for the mapping. +# Transforms lines from +# #define AF_INET 2 /* Internet IP Protocol */ +# to +# #define AA_FS_AF_MASK "local inet" +quiet_cmd_make-af = GEN $@ +cmd_make-af = echo "static const char *address_family_names[] = {" > $@ ;\ + sed $< >>$@ -r -n -e "/AF_MAX/d" -e "/AF_LOCAL/d" -e \ + 's/^\#define[ \t]+AF_([A-Z0-9_]+)[ \t]+([0-9]+)(.*)/[\2] = "\L\1",/p';\ + echo "};" >> $@ ;\ + echo -n '\#define AA_FS_AF_MASK "' >> $@ ;\ + sed -r -n 's/^\#define[ \t]+AF_([A-Z0-9_]+)[ \t]+([0-9]+)(.*)/\L\1/p'\ + $< | tr '\n' ' ' | sed -e 's/ $$/"\n/' >> $@ + +# Build a lower case string table of sock type names +# Transform lines from +# SOCK_STREAM = 1, +# to +# [1] = "stream", +quiet_cmd_make-sock = GEN $@ +cmd_make-sock = echo "static const char *sock_type_names[] = {" >> $@ ;\ + sed $^ >>$@ -r -n \ + -e 's/^\tSOCK_([A-Z0-9_]+)[\t]+=[ \t]+([0-9]+)(.*)/[\2] = "\L\1",/p';\ + echo "};" >> $@ # Build a lower case string table of rlimit names. # Transforms lines from @@ -61,6 +93,7 @@ cmd_make-rlim = echo "static const char *const rlim_names[RLIM_NLIMITS] = {" \ tr '\n' ' ' | sed -e 's/ $$/"\n/' >> $@ $(obj)/capability.o : $(obj)/capability_names.h +$(obj)/net.o : $(obj)/net_names.h $(obj)/resource.o : $(obj)/rlim_names.h $(obj)/capability_names.h : $(srctree)/include/uapi/linux/capability.h \ $(src)/Makefile @@ -68,3 +101,8 @@ $(obj)/capability_names.h : $(srctree)/include/uapi/linux/capability.h \ $(obj)/rlim_names.h : $(srctree)/include/uapi/asm-generic/resource.h \ $(src)/Makefile $(call cmd,make-rlim) +$(obj)/net_names.h : $(srctree)/include/linux/socket.h \ + $(srctree)/include/linux/net.h \ + $(src)/Makefile + $(call cmd,make-af) + $(call cmd,make-sock) diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index 729e595..181d961 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -807,6 +807,7 @@ static struct aa_fs_entry aa_fs_entry_features[] = { AA_FS_DIR("policy", aa_fs_entry_policy), AA_FS_DIR("domain", aa_fs_entry_domain), AA_FS_DIR("file", aa_fs_entry_file), + AA_FS_DIR("network", aa_fs_entry_network), AA_FS_FILE_U64("capability", VFS_CAP_FLAGS_MASK), AA_FS_DIR("rlimit", aa_fs_entry_rlimit), AA_FS_DIR("caps", aa_fs_entry_caps), diff --git a/security/apparmor/include/audit.h b/security/apparmor/include/audit.h index ba3dfd1..5d3c419 100644 --- a/security/apparmor/include/audit.h +++ b/security/apparmor/include/audit.h @@ -125,6 +125,10 @@ struct apparmor_audit_data { u32 denied; kuid_t ouid; } fs; + struct { + int type, protocol; + struct sock *sk; + } net; }; }; diff --git a/security/apparmor/include/net.h b/security/apparmor/include/net.h new file mode 100644 index 0000000..cb8a121 --- /dev/null +++ b/security/apparmor/include/net.h @@ -0,0 +1,44 @@ +/* + * AppArmor security module + * + * This file contains AppArmor network mediation definitions. + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2012 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#ifndef __AA_NET_H +#define __AA_NET_H + +#include + +#include "apparmorfs.h" + +/* struct aa_net - network confinement data + * @allowed: basic network families permissions + * @audit_network: which network permissions to force audit + * @quiet_network: which network permissions to quiet rejects + */ +struct aa_net { + u16 allow[AF_MAX]; + u16 audit[AF_MAX]; + u16 quiet[AF_MAX]; +}; + +extern struct aa_fs_entry aa_fs_entry_network[]; + +extern int aa_net_perm(int op, struct aa_profile *profile, u16 family, + int type, int protocol, struct sock *sk); +extern int aa_revalidate_sk(int op, struct sock *sk); + +static inline void aa_free_net_rules(struct aa_net *new) +{ + /* NOP */ +} + +#endif /* __AA_NET_H */ diff --git a/security/apparmor/include/policy.h b/security/apparmor/include/policy.h index 52275f0..4fc4dac 100644 --- a/security/apparmor/include/policy.h +++ b/security/apparmor/include/policy.h @@ -27,6 +27,7 @@ #include "capability.h" #include "domain.h" #include "file.h" +#include "net.h" #include "resource.h" extern const char *const aa_profile_mode_names[]; @@ -176,6 +177,7 @@ struct aa_replacedby { * @policy: general match rules governing policy * @file: The set of rules governing basic file access and domain transitions * @caps: capabilities for the profile + * @net: network controls for the profile * @rlimits: rlimits for the profile * * @dents: dentries for the profiles file entries in apparmorfs @@ -217,6 +219,7 @@ struct aa_profile { struct aa_policydb policy; struct aa_file_rules file; struct aa_caps caps; + struct aa_net net; struct aa_rlimit rlimits; unsigned char *hash; diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index 41b8cb1..d96b5f7 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -32,6 +32,7 @@ #include "include/context.h" #include "include/file.h" #include "include/ipc.h" +#include "include/net.h" #include "include/path.h" #include "include/policy.h" #include "include/procattr.h" @@ -584,6 +585,104 @@ static int apparmor_task_setrlimit(struct task_struct *task, return error; } +static int apparmor_socket_create(int family, int type, int protocol, int kern) +{ + struct aa_profile *profile; + int error = 0; + + if (kern) + return 0; + + profile = __aa_current_profile(); + if (!unconfined(profile)) + error = aa_net_perm(OP_CREATE, profile, family, type, protocol, + NULL); + return error; +} + +static int apparmor_socket_bind(struct socket *sock, + struct sockaddr *address, int addrlen) +{ + struct sock *sk = sock->sk; + + return aa_revalidate_sk(OP_BIND, sk); +} + +static int apparmor_socket_connect(struct socket *sock, + struct sockaddr *address, int addrlen) +{ + struct sock *sk = sock->sk; + + return aa_revalidate_sk(OP_CONNECT, sk); +} + +static int apparmor_socket_listen(struct socket *sock, int backlog) +{ + struct sock *sk = sock->sk; + + return aa_revalidate_sk(OP_LISTEN, sk); +} + +static int apparmor_socket_accept(struct socket *sock, struct socket *newsock) +{ + struct sock *sk = sock->sk; + + return aa_revalidate_sk(OP_ACCEPT, sk); +} + +static int apparmor_socket_sendmsg(struct socket *sock, + struct msghdr *msg, int size) +{ + struct sock *sk = sock->sk; + + return aa_revalidate_sk(OP_SENDMSG, sk); +} + +static int apparmor_socket_recvmsg(struct socket *sock, + struct msghdr *msg, int size, int flags) +{ + struct sock *sk = sock->sk; + + return aa_revalidate_sk(OP_RECVMSG, sk); +} + +static int apparmor_socket_getsockname(struct socket *sock) +{ + struct sock *sk = sock->sk; + + return aa_revalidate_sk(OP_GETSOCKNAME, sk); +} + +static int apparmor_socket_getpeername(struct socket *sock) +{ + struct sock *sk = sock->sk; + + return aa_revalidate_sk(OP_GETPEERNAME, sk); +} + +static int apparmor_socket_getsockopt(struct socket *sock, int level, + int optname) +{ + struct sock *sk = sock->sk; + + return aa_revalidate_sk(OP_GETSOCKOPT, sk); +} + +static int apparmor_socket_setsockopt(struct socket *sock, int level, + int optname) +{ + struct sock *sk = sock->sk; + + return aa_revalidate_sk(OP_SETSOCKOPT, sk); +} + +static int apparmor_socket_shutdown(struct socket *sock, int how) +{ + struct sock *sk = sock->sk; + + return aa_revalidate_sk(OP_SOCK_SHUTDOWN, sk); +} + static struct security_hook_list apparmor_hooks[] = { LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check), LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme), @@ -613,6 +712,19 @@ static struct security_hook_list apparmor_hooks[] = { LSM_HOOK_INIT(getprocattr, apparmor_getprocattr), LSM_HOOK_INIT(setprocattr, apparmor_setprocattr), + LSM_HOOK_INIT(socket_create, apparmor_socket_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(cred_alloc_blank, apparmor_cred_alloc_blank), LSM_HOOK_INIT(cred_free, apparmor_cred_free), LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare), diff --git a/security/apparmor/net.c b/security/apparmor/net.c new file mode 100644 index 0000000..003dd18 --- /dev/null +++ b/security/apparmor/net.c @@ -0,0 +1,162 @@ +/* + * AppArmor security module + * + * This file contains AppArmor network mediation + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2012 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#include "include/apparmor.h" +#include "include/audit.h" +#include "include/context.h" +#include "include/net.h" +#include "include/policy.h" + +#include "net_names.h" + +struct aa_fs_entry aa_fs_entry_network[] = { + AA_FS_FILE_STRING("af_mask", AA_FS_AF_MASK), + { } +}; + +/* audit callback for net specific fields */ +static void audit_cb(struct audit_buffer *ab, void *va) +{ + struct common_audit_data *sa = va; + + audit_log_format(ab, " family="); + if (address_family_names[sa->u.net->family]) { + audit_log_string(ab, address_family_names[sa->u.net->family]); + } else { + audit_log_format(ab, "\"unknown(%d)\"", sa->u.net->family); + } + audit_log_format(ab, " sock_type="); + if (sock_type_names[sa->aad->net.type]) { + audit_log_string(ab, sock_type_names[sa->aad->net.type]); + } else { + audit_log_format(ab, "\"unknown(%d)\"", sa->aad->net.type); + } + audit_log_format(ab, " protocol=%d", sa->aad->net.protocol); +} + +/** + * audit_net - audit network access + * @profile: profile being enforced (NOT NULL) + * @op: operation being checked + * @family: network family + * @type: network type + * @protocol: network protocol + * @sk: socket auditing is being applied to + * @error: error code for failure else 0 + * + * Returns: %0 or sa->error else other errorcode on failure + */ +static int audit_net(struct aa_profile *profile, int op, u16 family, int type, + int protocol, struct sock *sk, int error) +{ + int audit_type = AUDIT_APPARMOR_AUTO; + struct common_audit_data sa; + struct apparmor_audit_data aad = { }; + struct lsm_network_audit net = { }; + if (sk) { + sa.type = LSM_AUDIT_DATA_NET; + } else { + sa.type = LSM_AUDIT_DATA_NONE; + } + /* todo fill in socket addr info */ + sa.aad = &aad; + sa.u.net = &net; + sa.aad->op = op, + sa.u.net->family = family; + sa.u.net->sk = sk; + sa.aad->net.type = type; + sa.aad->net.protocol = protocol; + sa.aad->error = error; + + if (likely(!sa.aad->error)) { + u16 audit_mask = profile->net.audit[sa.u.net->family]; + if (likely((AUDIT_MODE(profile) != AUDIT_ALL) && + !(1 << sa.aad->net.type & audit_mask))) + return 0; + audit_type = AUDIT_APPARMOR_AUDIT; + } else { + u16 quiet_mask = profile->net.quiet[sa.u.net->family]; + u16 kill_mask = 0; + u16 denied = (1 << sa.aad->net.type) & ~quiet_mask; + + if (denied & kill_mask) + audit_type = AUDIT_APPARMOR_KILL; + + if ((denied & quiet_mask) && + AUDIT_MODE(profile) != AUDIT_NOQUIET && + AUDIT_MODE(profile) != AUDIT_ALL) + return COMPLAIN_MODE(profile) ? 0 : sa.aad->error; + } + + return aa_audit(audit_type, profile, GFP_KERNEL, &sa, audit_cb); +} + +/** + * aa_net_perm - very course network access check + * @op: operation being checked + * @profile: profile being enforced (NOT NULL) + * @family: network family + * @type: network type + * @protocol: network protocol + * + * Returns: %0 else error if permission denied + */ +int aa_net_perm(int op, struct aa_profile *profile, u16 family, int type, + int protocol, struct sock *sk) +{ + u16 family_mask; + int error; + + if ((family < 0) || (family >= AF_MAX)) + return -EINVAL; + + if ((type < 0) || (type >= SOCK_MAX)) + return -EINVAL; + + /* unix domain and netlink sockets are handled by ipc */ + if (family == AF_UNIX || family == AF_NETLINK) + return 0; + + family_mask = profile->net.allow[family]; + + error = (family_mask & (1 << type)) ? 0 : -EACCES; + + return audit_net(profile, op, family, type, protocol, sk, error); +} + +/** + * aa_revalidate_sk - Revalidate access to a sock + * @op: operation being checked + * @sk: sock being revalidated (NOT NULL) + * + * Returns: %0 else error if permission denied + */ +int aa_revalidate_sk(int op, struct sock *sk) +{ + struct aa_profile *profile; + int error = 0; + + /* aa_revalidate_sk should not be called from interrupt context + * don't mediate these calls as they are not task related + */ + if (in_interrupt()) + return 0; + + profile = __aa_current_profile(); + if (!unconfined(profile)) + error = aa_net_perm(op, profile, sk->sk_family, sk->sk_type, + sk->sk_protocol, sk); + + return error; +} diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c index 179e68d..f1a8541 100644 --- a/security/apparmor/policy.c +++ b/security/apparmor/policy.c @@ -603,6 +603,7 @@ void aa_free_profile(struct aa_profile *profile) aa_free_file_rules(&profile->file); aa_free_cap_rules(&profile->caps); + aa_free_net_rules(&profile->net); aa_free_rlimit_rules(&profile->rlimits); kzfree(profile->dirname); diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c index 1381206..7dc15ff 100644 --- a/security/apparmor/policy_unpack.c +++ b/security/apparmor/policy_unpack.c @@ -193,6 +193,19 @@ fail: return 0; } +static bool unpack_u16(struct aa_ext *e, u16 *data, const char *name) +{ + if (unpack_nameX(e, AA_U16, name)) { + if (!inbounds(e, sizeof(u16))) + return 0; + if (data) + *data = le16_to_cpu(get_unaligned((u16 *) e->pos)); + e->pos += sizeof(u16); + return 1; + } + return 0; +} + static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name) { if (unpack_nameX(e, AA_U32, name)) { @@ -476,6 +489,7 @@ static struct aa_profile *unpack_profile(struct aa_ext *e) { struct aa_profile *profile = NULL; const char *name = NULL; + size_t size = 0; int i, error = -EPROTO; kernel_cap_t tmpcap; u32 tmp; @@ -576,6 +590,38 @@ static struct aa_profile *unpack_profile(struct aa_ext *e) if (!unpack_rlimits(e, profile)) goto fail; + size = unpack_array(e, "net_allowed_af"); + if (size) { + + for (i = 0; i < size; i++) { + /* discard extraneous rules that this kernel will + * never request + */ + if (i >= AF_MAX) { + u16 tmp; + if (!unpack_u16(e, &tmp, NULL) || + !unpack_u16(e, &tmp, NULL) || + !unpack_u16(e, &tmp, NULL)) + goto fail; + continue; + } + if (!unpack_u16(e, &profile->net.allow[i], NULL)) + goto fail; + if (!unpack_u16(e, &profile->net.audit[i], NULL)) + goto fail; + if (!unpack_u16(e, &profile->net.quiet[i], NULL)) + goto fail; + } + if (!unpack_nameX(e, AA_ARRAYEND, NULL)) + goto fail; + } + /* + * allow unix domain and netlink sockets they are handled + * by IPC + */ + profile->net.allow[AF_UNIX] = 0xffff; + profile->net.allow[AF_NETLINK] = 0xffff; + if (unpack_nameX(e, AA_STRUCT, "policydb")) { /* generic policy dfa - optional and may be NULL */ profile->policy.dfa = unpack_dfa(e); commit f5c5644745201b5b7d398e841e5045d0a5d14b18 Author: John Johansen Date: Fri Jun 29 17:34:00 2012 -0700 apparmor: Fix quieting of audit messages for network mediation If a profile specified a quieting of network denials for a given rule by either the quiet or deny rule qualifiers, the resultant quiet mask for denied requests was applied incorrectly, resulting in two potential bugs. 1. The misapplied quiet mask would prevent denials from being correctly tested against the kill mask/mode. Thus network access requests that should have resulted in the application being killed did not. 2. The actual quieting of the denied network request was not being applied. This would result in network rejections always being logged even when they had been specifically marked as quieted. Signed-off-by: John Johansen diff --git a/security/apparmor/net.c b/security/apparmor/net.c index 003dd18..6e6e5c9 100644 --- a/security/apparmor/net.c +++ b/security/apparmor/net.c @@ -88,7 +88,7 @@ static int audit_net(struct aa_profile *profile, int op, u16 family, int type, } else { u16 quiet_mask = profile->net.quiet[sa.u.net->family]; u16 kill_mask = 0; - u16 denied = (1 << sa.aad->net.type) & ~quiet_mask; + u16 denied = (1 << sa.aad->net.type); if (denied & kill_mask) audit_type = AUDIT_APPARMOR_KILL; commit 0269f1631e1496798e5b0a319ff05b1133cfeaa3 Author: John Johansen Date: Wed May 16 10:58:05 2012 -0700 UBUNTU: SAUCE: apparmor: Add the ability to mediate mount Add the ability for apparmor to do mediation of mount operations. Mount rules require an updated apparmor_parser (2.8 series) for policy compilation. The basic form of the rules are. [audit] [deny] mount [conds]* [device] [ -> [conds] path], [audit] [deny] remount [conds]* [path], [audit] [deny] umount [conds]* [path], [audit] [deny] pivotroot [oldroot=] remount is just a short cut for mount options=remount where [conds] can be fstype= options= Example mount commands mount, # allow all mounts, but not umount or pivotroot mount fstype=procfs, # allow mounting procfs anywhere mount options=(bind, ro) /foo -> /bar, # readonly bind mount mount /dev/sda -> /mnt, mount /dev/sd** -> /mnt/**, mount fstype=overlayfs options=(rw,upperdir=/tmp/upper/,lowerdir=/) -> /mnt/ umount, umount /m*, See the apparmor userspace for full documentation Signed-off-by: John Johansen Acked-by: Kees Cook diff --git a/security/apparmor/Makefile b/security/apparmor/Makefile index 5dbb72f..89b3445 100644 --- a/security/apparmor/Makefile +++ b/security/apparmor/Makefile @@ -4,7 +4,7 @@ obj-$(CONFIG_SECURITY_APPARMOR) += apparmor.o apparmor-y := apparmorfs.o audit.o capability.o context.o ipc.o lib.o match.o \ path.o domain.o policy.o policy_unpack.o procattr.o lsm.o \ - resource.o sid.o file.o net.o + resource.o sid.o file.o net.o mount.o apparmor-$(CONFIG_SECURITY_APPARMOR_HASH) += crypto.o clean-files := capability_names.h rlim_names.h net_names.h diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index 181d961..5fb67f6 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -800,7 +800,18 @@ static struct aa_fs_entry aa_fs_entry_domain[] = { static struct aa_fs_entry aa_fs_entry_policy[] = { AA_FS_FILE_BOOLEAN("set_load", 1), - {} + { } +}; + +static struct aa_fs_entry aa_fs_entry_mount[] = { + AA_FS_FILE_STRING("mask", "mount umount"), + { } +}; + +static struct aa_fs_entry aa_fs_entry_namespaces[] = { + AA_FS_FILE_BOOLEAN("profile", 1), + AA_FS_FILE_BOOLEAN("pivot_root", 1), + { } }; static struct aa_fs_entry aa_fs_entry_features[] = { @@ -808,6 +819,8 @@ static struct aa_fs_entry aa_fs_entry_features[] = { AA_FS_DIR("domain", aa_fs_entry_domain), AA_FS_DIR("file", aa_fs_entry_file), AA_FS_DIR("network", aa_fs_entry_network), + AA_FS_DIR("mount", aa_fs_entry_mount), + AA_FS_DIR("namespaces", aa_fs_entry_namespaces), AA_FS_FILE_U64("capability", VFS_CAP_FLAGS_MASK), AA_FS_DIR("rlimit", aa_fs_entry_rlimit), AA_FS_DIR("caps", aa_fs_entry_caps), diff --git a/security/apparmor/audit.c b/security/apparmor/audit.c index 3a7f1da..c2a8b8a 100644 --- a/security/apparmor/audit.c +++ b/security/apparmor/audit.c @@ -44,6 +44,10 @@ const char *const op_table[] = { "file_mmap", "file_mprotect", + "pivotroot", + "mount", + "umount", + "create", "post_create", "bind", diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c index fc3036b..f2a83b4 100644 --- a/security/apparmor/domain.c +++ b/security/apparmor/domain.c @@ -236,7 +236,7 @@ static const char *next_name(int xtype, const char *name) * * Returns: refcounted profile, or NULL on failure (MAYBE NULL) */ -static struct aa_profile *x_table_lookup(struct aa_profile *profile, u32 xindex) +struct aa_profile *x_table_lookup(struct aa_profile *profile, u32 xindex) { struct aa_profile *new_profile = NULL; struct aa_namespace *ns = profile->ns; diff --git a/security/apparmor/include/apparmor.h b/security/apparmor/include/apparmor.h index 5d721e9..b57da7b 100644 --- a/security/apparmor/include/apparmor.h +++ b/security/apparmor/include/apparmor.h @@ -30,8 +30,9 @@ #define AA_CLASS_NET 4 #define AA_CLASS_RLIMITS 5 #define AA_CLASS_DOMAIN 6 +#define AA_CLASS_MOUNT 7 -#define AA_CLASS_LAST AA_CLASS_DOMAIN +#define AA_CLASS_LAST AA_CLASS_MOUNT /* Control parameters settable through module/boot flags */ extern enum audit_mode aa_g_audit; diff --git a/security/apparmor/include/audit.h b/security/apparmor/include/audit.h index 5d3c419..b9f1d57 100644 --- a/security/apparmor/include/audit.h +++ b/security/apparmor/include/audit.h @@ -72,6 +72,10 @@ enum aa_ops { OP_FMMAP, OP_FMPROT, + OP_PIVOTROOT, + OP_MOUNT, + OP_UMOUNT, + OP_CREATE, OP_POST_CREATE, OP_BIND, @@ -120,6 +124,13 @@ struct apparmor_audit_data { unsigned long max; } rlim; struct { + const char *src_name; + const char *type; + const char *trans; + const char *data; + unsigned long flags; + } mnt; + struct { const char *target; u32 request; u32 denied; diff --git a/security/apparmor/include/domain.h b/security/apparmor/include/domain.h index de04464..a3f70c5 100644 --- a/security/apparmor/include/domain.h +++ b/security/apparmor/include/domain.h @@ -23,6 +23,8 @@ struct aa_domain { char **table; }; +struct aa_profile *x_table_lookup(struct aa_profile *profile, u32 xindex); + int apparmor_bprm_set_creds(struct linux_binprm *bprm); int apparmor_bprm_secureexec(struct linux_binprm *bprm); void apparmor_bprm_committing_creds(struct linux_binprm *bprm); diff --git a/security/apparmor/include/mount.h b/security/apparmor/include/mount.h new file mode 100644 index 0000000..a43b1d6 --- /dev/null +++ b/security/apparmor/include/mount.h @@ -0,0 +1,54 @@ +/* + * AppArmor security module + * + * This file contains AppArmor file mediation function definitions. + * + * Copyright 2012 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#ifndef __AA_MOUNT_H +#define __AA_MOUNT_H + +#include +#include + +#include "domain.h" +#include "policy.h" + +/* mount perms */ +#define AA_MAY_PIVOTROOT 0x01 +#define AA_MAY_MOUNT 0x02 +#define AA_MAY_UMOUNT 0x04 +#define AA_AUDIT_DATA 0x40 +#define AA_CONT_MATCH 0x40 + +#define AA_MS_IGNORE_MASK (MS_KERNMOUNT | MS_NOSEC | MS_ACTIVE | MS_BORN) + +int aa_remount(struct aa_profile *profile, const struct path *path, + unsigned long flags, void *data); + +int aa_bind_mount(struct aa_profile *profile, const struct path *path, + const char *old_name, unsigned long flags); + + +int aa_mount_change_type(struct aa_profile *profile, const struct path *path, + unsigned long flags); + +int aa_move_mount(struct aa_profile *profile, const struct path *path, + const char *old_name); + +int aa_new_mount(struct aa_profile *profile, const char *dev_name, + const struct path *path, const char *type, unsigned long flags, + void *data); + +int aa_umount(struct aa_profile *profile, struct vfsmount *mnt, int flags); + +int aa_pivotroot(struct aa_profile *profile, const struct path *old_path, + const struct path *new_path); + +#endif /* __AA_MOUNT_H */ diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c index d96b5f7..7a02376 100644 --- a/security/apparmor/lsm.c +++ b/security/apparmor/lsm.c @@ -36,6 +36,7 @@ #include "include/path.h" #include "include/policy.h" #include "include/procattr.h" +#include "include/mount.h" /* Flag indicating whether initialization completed */ int apparmor_initialized __initdata; @@ -469,6 +470,61 @@ static int apparmor_file_mprotect(struct vm_area_struct *vma, !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0); } +static int apparmor_sb_mount(const char *dev_name, const struct path *path, + const char *type, unsigned long flags, void *data) +{ + struct aa_profile *profile; + int error = 0; + + /* Discard magic */ + if ((flags & MS_MGC_MSK) == MS_MGC_VAL) + flags &= ~MS_MGC_MSK; + + flags &= ~AA_MS_IGNORE_MASK; + + profile = __aa_current_profile(); + if (!unconfined(profile)) { + if (flags & MS_REMOUNT) + error = aa_remount(profile, path, flags, data); + else if (flags & MS_BIND) + error = aa_bind_mount(profile, path, dev_name, flags); + else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE | + MS_UNBINDABLE)) + error = aa_mount_change_type(profile, path, flags); + else if (flags & MS_MOVE) + error = aa_move_mount(profile, path, dev_name); + else + error = aa_new_mount(profile, dev_name, path, type, + flags, data); + } + return error; +} + +static int apparmor_sb_umount(struct vfsmount *mnt, int flags) +{ + struct aa_profile *profile; + int error = 0; + + profile = __aa_current_profile(); + if (!unconfined(profile)) + error = aa_umount(profile, mnt, flags); + + return error; +} + +static int apparmor_sb_pivotroot(const struct path *old_path, + const struct path *new_path) +{ + struct aa_profile *profile; + int error = 0; + + profile = __aa_current_profile(); + if (!unconfined(profile)) + error = aa_pivotroot(profile, old_path, new_path); + + return error; +} + static int apparmor_getprocattr(struct task_struct *task, char *name, char **value) { @@ -689,6 +745,10 @@ static struct security_hook_list apparmor_hooks[] = { LSM_HOOK_INIT(capget, apparmor_capget), LSM_HOOK_INIT(capable, apparmor_capable), + LSM_HOOK_INIT(sb_mount, apparmor_sb_mount), + LSM_HOOK_INIT(sb_umount, apparmor_sb_umount), + LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot), + LSM_HOOK_INIT(path_link, apparmor_path_link), LSM_HOOK_INIT(path_unlink, apparmor_path_unlink), LSM_HOOK_INIT(path_symlink, apparmor_path_symlink), diff --git a/security/apparmor/mount.c b/security/apparmor/mount.c new file mode 100644 index 0000000..9cf9170 --- /dev/null +++ b/security/apparmor/mount.c @@ -0,0 +1,620 @@ +/* + * AppArmor security module + * + * This file contains AppArmor mediation of files + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2012 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#include +#include +#include + +#include "include/apparmor.h" +#include "include/audit.h" +#include "include/context.h" +#include "include/domain.h" +#include "include/file.h" +#include "include/match.h" +#include "include/mount.h" +#include "include/path.h" +#include "include/policy.h" + + +static void audit_mnt_flags(struct audit_buffer *ab, unsigned long flags) +{ + if (flags & MS_RDONLY) + audit_log_format(ab, "ro"); + else + audit_log_format(ab, "rw"); + if (flags & MS_NOSUID) + audit_log_format(ab, ", nosuid"); + if (flags & MS_NODEV) + audit_log_format(ab, ", nodev"); + if (flags & MS_NOEXEC) + audit_log_format(ab, ", noexec"); + if (flags & MS_SYNCHRONOUS) + audit_log_format(ab, ", sync"); + if (flags & MS_REMOUNT) + audit_log_format(ab, ", remount"); + if (flags & MS_MANDLOCK) + audit_log_format(ab, ", mand"); + if (flags & MS_DIRSYNC) + audit_log_format(ab, ", dirsync"); + if (flags & MS_NOATIME) + audit_log_format(ab, ", noatime"); + if (flags & MS_NODIRATIME) + audit_log_format(ab, ", nodiratime"); + if (flags & MS_BIND) + audit_log_format(ab, flags & MS_REC ? ", rbind" : ", bind"); + if (flags & MS_MOVE) + audit_log_format(ab, ", move"); + if (flags & MS_SILENT) + audit_log_format(ab, ", silent"); + if (flags & MS_POSIXACL) + audit_log_format(ab, ", acl"); + if (flags & MS_UNBINDABLE) + audit_log_format(ab, flags & MS_REC ? ", runbindable" : + ", unbindable"); + if (flags & MS_PRIVATE) + audit_log_format(ab, flags & MS_REC ? ", rprivate" : + ", private"); + if (flags & MS_SLAVE) + audit_log_format(ab, flags & MS_REC ? ", rslave" : + ", slave"); + if (flags & MS_SHARED) + audit_log_format(ab, flags & MS_REC ? ", rshared" : + ", shared"); + if (flags & MS_RELATIME) + audit_log_format(ab, ", relatime"); + if (flags & MS_I_VERSION) + audit_log_format(ab, ", iversion"); + if (flags & MS_STRICTATIME) + audit_log_format(ab, ", strictatime"); + if (flags & MS_NOUSER) + audit_log_format(ab, ", nouser"); +} + +/** + * audit_cb - call back for mount specific audit fields + * @ab: audit_buffer (NOT NULL) + * @va: audit struct to audit values of (NOT NULL) + */ +static void audit_cb(struct audit_buffer *ab, void *va) +{ + struct common_audit_data *sa = va; + + if (sa->aad->mnt.type) { + audit_log_format(ab, " fstype="); + audit_log_untrustedstring(ab, sa->aad->mnt.type); + } + if (sa->aad->mnt.src_name) { + audit_log_format(ab, " srcname="); + audit_log_untrustedstring(ab, sa->aad->mnt.src_name); + } + if (sa->aad->mnt.trans) { + audit_log_format(ab, " trans="); + audit_log_untrustedstring(ab, sa->aad->mnt.trans); + } + if (sa->aad->mnt.flags || sa->aad->op == OP_MOUNT) { + audit_log_format(ab, " flags=\""); + audit_mnt_flags(ab, sa->aad->mnt.flags); + audit_log_format(ab, "\""); + } + if (sa->aad->mnt.data) { + audit_log_format(ab, " options="); + audit_log_untrustedstring(ab, sa->aad->mnt.data); + } +} + +/** + * audit_mount - handle the auditing of mount operations + * @profile: the profile being enforced (NOT NULL) + * @gfp: allocation flags + * @op: operation being mediated (NOT NULL) + * @name: name of object being mediated (MAYBE NULL) + * @src_name: src_name of object being mediated (MAYBE_NULL) + * @type: type of filesystem (MAYBE_NULL) + * @trans: name of trans (MAYBE NULL) + * @flags: filesystem idependent mount flags + * @data: filesystem mount flags + * @request: permissions requested + * @perms: the permissions computed for the request (NOT NULL) + * @info: extra information message (MAYBE NULL) + * @error: 0 if operation allowed else failure error code + * + * Returns: %0 or error on failure + */ +static int audit_mount(struct aa_profile *profile, gfp_t gfp, int op, + const char *name, const char *src_name, + const char *type, const char *trans, + unsigned long flags, const void *data, u32 request, + struct file_perms *perms, const char *info, int error) +{ + int audit_type = AUDIT_APPARMOR_AUTO; + struct common_audit_data sa = { }; + struct apparmor_audit_data aad = { }; + + if (likely(!error)) { + u32 mask = perms->audit; + + if (unlikely(AUDIT_MODE(profile) == AUDIT_ALL)) + mask = 0xffff; + + /* mask off perms that are not being force audited */ + request &= mask; + + if (likely(!request)) + return 0; + audit_type = AUDIT_APPARMOR_AUDIT; + } else { + /* only report permissions that were denied */ + request = request & ~perms->allow; + + if (request & perms->kill) + audit_type = AUDIT_APPARMOR_KILL; + + /* quiet known rejects, assumes quiet and kill do not overlap */ + if ((request & perms->quiet) && + AUDIT_MODE(profile) != AUDIT_NOQUIET && + AUDIT_MODE(profile) != AUDIT_ALL) + request &= ~perms->quiet; + + if (!request) + return COMPLAIN_MODE(profile) ? + complain_error(error) : error; + } + + sa.type = LSM_AUDIT_DATA_NONE; + sa.aad = &aad; + sa.aad->op = op; + sa.aad->name = name; + sa.aad->mnt.src_name = src_name; + sa.aad->mnt.type = type; + sa.aad->mnt.trans = trans; + sa.aad->mnt.flags = flags; + if (data && (perms->audit & AA_AUDIT_DATA)) + sa.aad->mnt.data = data; + sa.aad->info = info; + sa.aad->error = error; + + return aa_audit(audit_type, profile, gfp, &sa, audit_cb); +} + +/** + * match_mnt_flags - Do an ordered match on mount flags + * @dfa: dfa to match against + * @state: state to start in + * @flags: mount flags to match against + * + * Mount flags are encoded as an ordered match. This is done instead of + * checking against a simple bitmask, to allow for logical operations + * on the flags. + * + * Returns: next state after flags match + */ +static unsigned int match_mnt_flags(struct aa_dfa *dfa, unsigned int state, + unsigned long flags) +{ + unsigned int i; + + for (i = 0; i <= 31 ; ++i) { + if ((1 << i) & flags) + state = aa_dfa_next(dfa, state, i + 1); + } + + return state; +} + +/** + * compute_mnt_perms - compute mount permission associated with @state + * @dfa: dfa to match against (NOT NULL) + * @state: state match finished in + * + * Returns: mount permissions + */ +static struct file_perms compute_mnt_perms(struct aa_dfa *dfa, + unsigned int state) +{ + struct file_perms perms; + + perms.kill = 0; + perms.allow = dfa_user_allow(dfa, state); + perms.audit = dfa_user_audit(dfa, state); + perms.quiet = dfa_user_quiet(dfa, state); + perms.xindex = dfa_user_xindex(dfa, state); + + return perms; +} + +static const char const *mnt_info_table[] = { + "match succeeded", + "failed mntpnt match", + "failed srcname match", + "failed type match", + "failed flags match", + "failed data match" +}; + +/* + * Returns 0 on success else element that match failed in, this is the + * index into the mnt_info_table above + */ +static int do_match_mnt(struct aa_dfa *dfa, unsigned int start, + const char *mntpnt, const char *devname, + const char *type, unsigned long flags, + void *data, bool binary, struct file_perms *perms) +{ + unsigned int state; + + state = aa_dfa_match(dfa, start, mntpnt); + state = aa_dfa_null_transition(dfa, state); + if (!state) + return 1; + + if (devname) + state = aa_dfa_match(dfa, state, devname); + state = aa_dfa_null_transition(dfa, state); + if (!state) + return 2; + + if (type) + state = aa_dfa_match(dfa, state, type); + state = aa_dfa_null_transition(dfa, state); + if (!state) + return 3; + + state = match_mnt_flags(dfa, state, flags); + if (!state) + return 4; + *perms = compute_mnt_perms(dfa, state); + if (perms->allow & AA_MAY_MOUNT) + return 0; + + /* only match data if not binary and the DFA flags data is expected */ + if (data && !binary && (perms->allow & AA_CONT_MATCH)) { + state = aa_dfa_null_transition(dfa, state); + if (!state) + return 4; + + state = aa_dfa_match(dfa, state, data); + if (!state) + return 5; + *perms = compute_mnt_perms(dfa, state); + if (perms->allow & AA_MAY_MOUNT) + return 0; + } + + /* failed at end of flags match */ + return 4; +} + +/** + * match_mnt - handle path matching for mount + * @profile: the confining profile + * @mntpnt: string for the mntpnt (NOT NULL) + * @devname: string for the devname/src_name (MAYBE NULL) + * @type: string for the dev type (MAYBE NULL) + * @flags: mount flags to match + * @data: fs mount data (MAYBE NULL) + * @binary: whether @data is binary + * @perms: Returns: permission found by the match + * @info: Returns: infomation string about the match for logging + * + * Returns: 0 on success else error + */ +static int match_mnt(struct aa_profile *profile, const char *mntpnt, + const char *devname, const char *type, + unsigned long flags, void *data, bool binary, + struct file_perms *perms, const char **info) +{ + int pos; + + if (!profile->policy.dfa) + return -EACCES; + + pos = do_match_mnt(profile->policy.dfa, + profile->policy.start[AA_CLASS_MOUNT], + mntpnt, devname, type, flags, data, binary, perms); + if (pos) { + *info = mnt_info_table[pos]; + return -EACCES; + } + + return 0; +} + +static int path_flags(struct aa_profile *profile, const struct path *path) +{ + return profile->path_flags | + S_ISDIR(path->dentry->d_inode->i_mode) ? PATH_IS_DIR : 0; +} + +int aa_remount(struct aa_profile *profile, const struct path *path, + unsigned long flags, void *data) +{ + struct file_perms perms = { }; + const char *name, *info = NULL; + char *buffer = NULL; + int binary, error; + + binary = path->dentry->d_sb->s_type->fs_flags & FS_BINARY_MOUNTDATA; + + error = aa_path_name(path, path_flags(profile, path), &buffer, &name, + &info); + if (error) + goto audit; + + error = match_mnt(profile, name, NULL, NULL, flags, data, binary, + &perms, &info); + +audit: + error = audit_mount(profile, GFP_KERNEL, OP_MOUNT, name, NULL, NULL, + NULL, flags, data, AA_MAY_MOUNT, &perms, info, + error); + kfree(buffer); + + return error; +} + +int aa_bind_mount(struct aa_profile *profile, const struct path *path, + const char *dev_name, unsigned long flags) +{ + struct file_perms perms = { }; + char *buffer = NULL, *old_buffer = NULL; + const char *name, *old_name = NULL, *info = NULL; + struct path old_path; + int error; + + if (!dev_name || !*dev_name) + return -EINVAL; + + flags &= MS_REC | MS_BIND; + + error = aa_path_name(path, path_flags(profile, path), &buffer, &name, + &info); + if (error) + goto audit; + + error = kern_path(dev_name, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &old_path); + if (error) + goto audit; + + error = aa_path_name(&old_path, path_flags(profile, &old_path), + &old_buffer, &old_name, &info); + path_put(&old_path); + if (error) + goto audit; + + error = match_mnt(profile, name, old_name, NULL, flags, NULL, 0, + &perms, &info); + +audit: + error = audit_mount(profile, GFP_KERNEL, OP_MOUNT, name, old_name, + NULL, NULL, flags, NULL, AA_MAY_MOUNT, &perms, + info, error); + kfree(buffer); + kfree(old_buffer); + + return error; +} + +int aa_mount_change_type(struct aa_profile *profile, const struct path *path, + unsigned long flags) +{ + struct file_perms perms = { }; + char *buffer = NULL; + const char *name, *info = NULL; + int error; + + /* These are the flags allowed by do_change_type() */ + flags &= (MS_REC | MS_SILENT | MS_SHARED | MS_PRIVATE | MS_SLAVE | + MS_UNBINDABLE); + + error = aa_path_name(path, path_flags(profile, path), &buffer, &name, + &info); + if (error) + goto audit; + + error = match_mnt(profile, name, NULL, NULL, flags, NULL, 0, &perms, + &info); + +audit: + error = audit_mount(profile, GFP_KERNEL, OP_MOUNT, name, NULL, NULL, + NULL, flags, NULL, AA_MAY_MOUNT, &perms, info, + error); + kfree(buffer); + + return error; +} + +int aa_move_mount(struct aa_profile *profile, const struct path *path, + const char *orig_name) +{ + struct file_perms perms = { }; + char *buffer = NULL, *old_buffer = NULL; + const char *name, *old_name = NULL, *info = NULL; + struct path old_path; + int error; + + if (!orig_name || !*orig_name) + return -EINVAL; + + error = aa_path_name(path, path_flags(profile, path), &buffer, &name, + &info); + if (error) + goto audit; + + error = kern_path(orig_name, LOOKUP_FOLLOW, &old_path); + if (error) + goto audit; + + error = aa_path_name(&old_path, path_flags(profile, &old_path), + &old_buffer, &old_name, &info); + path_put(&old_path); + if (error) + goto audit; + + error = match_mnt(profile, name, old_name, NULL, MS_MOVE, NULL, 0, + &perms, &info); + +audit: + error = audit_mount(profile, GFP_KERNEL, OP_MOUNT, name, old_name, + NULL, NULL, MS_MOVE, NULL, AA_MAY_MOUNT, &perms, + info, error); + kfree(buffer); + kfree(old_buffer); + + return error; +} + +int aa_new_mount(struct aa_profile *profile, const char *orig_dev_name, + const struct path *path, const char *type, unsigned long flags, + void *data) +{ + struct file_perms perms = { }; + char *buffer = NULL, *dev_buffer = NULL; + const char *name = NULL, *dev_name = NULL, *info = NULL; + int binary = 1; + int error; + + dev_name = orig_dev_name; + if (type) { + int requires_dev; + struct file_system_type *fstype = get_fs_type(type); + if (!fstype) + return -ENODEV; + + binary = fstype->fs_flags & FS_BINARY_MOUNTDATA; + requires_dev = fstype->fs_flags & FS_REQUIRES_DEV; + put_filesystem(fstype); + + if (requires_dev) { + struct path dev_path; + + if (!dev_name || !*dev_name) { + error = -ENOENT; + goto out; + } + + error = kern_path(dev_name, LOOKUP_FOLLOW, &dev_path); + if (error) + goto audit; + + error = aa_path_name(&dev_path, + path_flags(profile, &dev_path), + &dev_buffer, &dev_name, &info); + path_put(&dev_path); + if (error) + goto audit; + } + } + + error = aa_path_name(path, path_flags(profile, path), &buffer, &name, + &info); + if (error) + goto audit; + + error = match_mnt(profile, name, dev_name, type, flags, data, binary, + &perms, &info); + +audit: + error = audit_mount(profile, GFP_KERNEL, OP_MOUNT, name, dev_name, + type, NULL, flags, data, AA_MAY_MOUNT, &perms, info, + error); + kfree(buffer); + kfree(dev_buffer); + +out: + return error; + +} + +int aa_umount(struct aa_profile *profile, struct vfsmount *mnt, int flags) +{ + struct file_perms perms = { }; + char *buffer = NULL; + const char *name, *info = NULL; + int error; + + struct path path = { mnt, mnt->mnt_root }; + error = aa_path_name(&path, path_flags(profile, &path), &buffer, &name, + &info); + if (error) + goto audit; + + if (!error && profile->policy.dfa) { + unsigned int state; + state = aa_dfa_match(profile->policy.dfa, + profile->policy.start[AA_CLASS_MOUNT], + name); + perms = compute_mnt_perms(profile->policy.dfa, state); + } + + if (AA_MAY_UMOUNT & ~perms.allow) + error = -EACCES; + +audit: + error = audit_mount(profile, GFP_KERNEL, OP_UMOUNT, name, NULL, NULL, + NULL, 0, NULL, AA_MAY_UMOUNT, &perms, info, error); + kfree(buffer); + + return error; +} + +int aa_pivotroot(struct aa_profile *profile, const struct path *old_path, + const struct path *new_path) +{ + struct file_perms perms = { }; + struct aa_profile *target = NULL; + char *old_buffer = NULL, *new_buffer = NULL; + const char *old_name, *new_name = NULL, *info = NULL; + int error; + + error = aa_path_name(old_path, path_flags(profile, old_path), + &old_buffer, &old_name, &info); + if (error) + goto audit; + + error = aa_path_name(new_path, path_flags(profile, new_path), + &new_buffer, &new_name, &info); + if (error) + goto audit; + + if (profile->policy.dfa) { + unsigned int state; + state = aa_dfa_match(profile->policy.dfa, + profile->policy.start[AA_CLASS_MOUNT], + new_name); + state = aa_dfa_null_transition(profile->policy.dfa, state); + state = aa_dfa_match(profile->policy.dfa, state, old_name); + perms = compute_mnt_perms(profile->policy.dfa, state); + } + + if (AA_MAY_PIVOTROOT & perms.allow) { + if ((perms.xindex & AA_X_TYPE_MASK) == AA_X_TABLE) { + target = x_table_lookup(profile, perms.xindex); + if (!target) + error = -ENOENT; + else + error = aa_replace_current_profile(target); + } + } else + error = -EACCES; + +audit: + error = audit_mount(profile, GFP_KERNEL, OP_PIVOTROOT, new_name, + old_name, NULL, target ? target->base.name : NULL, + 0, NULL, AA_MAY_PIVOTROOT, &perms, info, error); + aa_put_profile(target); + kfree(old_buffer); + kfree(new_buffer); + + return error; +}