![John Johansen](/assets/img/avatar_default.png)
The path_max parameter determines the max size of buffers allocated but it should not be setable at run time. If can be used to cause an oops root@ubuntu:~# echo 16777216 > /sys/module/apparmor/parameters/path_max root@ubuntu:~# cat /sys/module/apparmor/parameters/path_max Killed [ 122.141911] BUG: unable to handle kernel paging request at ffff880080945fff [ 122.143497] IP: [<ffffffff81228844>] d_absolute_path+0x44/0xa0 [ 122.144742] PGD 220c067 PUD 0 [ 122.145453] Oops: 0002 [#1] SMP [ 122.146204] Modules linked in: vmw_vsock_vmci_transport vsock ppdev vmw_balloon snd_ens1371 btusb snd_ac97_codec gameport snd_rawmidi btrtl snd_seq_device ac97_bus btbcm btintel snd_pcm input_leds bluetooth snd_timer snd joydev soundcore serio_raw coretemp shpchp nfit parport_pc i2c_piix4 8250_fintek vmw_vmci parport mac_hid ib_iser rdma_cm iw_cm ib_cm ib_sa ib_mad ib_core ib_addr iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi autofs4 btrfs raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear hid_generic usbhid hid crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd vmwgfx psmouse mptspi ttm mptscsih drm_kms_helper mptbase syscopyarea scsi_transport_spi sysfillrect [ 122.163365] ahci sysimgblt e1000 fb_sys_fops libahci drm pata_acpi fjes [ 122.164747] CPU: 3 PID: 1501 Comm: bash Not tainted 4.4.0-59-generic #80-Ubuntu [ 122.166250] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015 [ 122.168611] task: ffff88003496aa00 ti: ffff880076474000 task.ti: ffff880076474000 [ 122.170018] RIP: 0010:[<ffffffff81228844>] [<ffffffff81228844>] d_absolute_path+0x44/0xa0 [ 122.171525] RSP: 0018:ffff880076477b90 EFLAGS: 00010206 [ 122.172462] RAX: ffff880080945fff RBX: 0000000000000000 RCX: 0000000001000000 [ 122.173709] RDX: 0000000000ffffff RSI: ffff880080946000 RDI: ffff8800348a1010 [ 122.174978] RBP: ffff880076477bb8 R08: ffff880076477c80 R09: 0000000000000000 [ 122.176227] R10: 00007ffffffff000 R11: ffff88007f946000 R12: ffff88007f946000 [ 122.177496] R13: ffff880076477c80 R14: ffff8800348a1010 R15: ffff8800348a2400 [ 122.178745] FS: 00007fd459eb4700(0000) GS:ffff88007b6c0000(0000) knlGS:0000000000000000 [ 122.180176] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 122.181186] CR2: ffff880080945fff CR3: 0000000073422000 CR4: 00000000001406e0 [ 122.182469] Stack: [ 122.182843] 00ffffff00000001 ffff880080946000 0000000000000000 0000000000000000 [ 122.184409] 00000000570f789c ffff880076477c30 ffffffff81385671 ffff88007a2e7a58 [ 122.185810] 0000000000000000 ffff880076477c88 01000000008a1000 0000000000000000 [ 122.187231] Call Trace: [ 122.187680] [<ffffffff81385671>] aa_path_name+0x81/0x370 [ 122.188637] [<ffffffff813875dd>] profile_transition+0xbd/0xb80 [ 122.190181] [<ffffffff811af9bc>] ? zone_statistics+0x7c/0xa0 [ 122.191674] [<ffffffff81389b20>] apparmor_bprm_set_creds+0x9b0/0xac0 [ 122.193288] [<ffffffff812e1971>] ? ext4_xattr_get+0x81/0x220 [ 122.194793] [<ffffffff812e800c>] ? ext4_xattr_security_get+0x1c/0x30 [ 122.196392] [<ffffffff813449b9>] ? get_vfs_caps_from_disk+0x69/0x110 [ 122.198004] [<ffffffff81232d4f>] ? mnt_may_suid+0x3f/0x50 [ 122.199737] [<ffffffff81344b03>] ? cap_bprm_set_creds+0xa3/0x600 [ 122.201377] [<ffffffff81346e53>] security_bprm_set_creds+0x33/0x50 [ 122.203024] [<ffffffff81214ce5>] prepare_binprm+0x85/0x190 [ 122.204515] [<ffffffff81216545>] do_execveat_common.isra.33+0x485/0x710 [ 122.206200] [<ffffffff81216a6a>] SyS_execve+0x3a/0x50 [ 122.207615] [<ffffffff81838795>] stub_execve+0x5/0x5 [ 122.208978] [<ffffffff818384f2>] ? entry_SYSCALL_64_fastpath+0x16/0x71 [ 122.210615] Code: f8 31 c0 48 63 c2 83 ea 01 48 c7 45 e8 00 00 00 00 48 01 c6 85 d2 48 c7 45 f0 00 00 00 00 48 89 75 e0 89 55 dc 78 0c 48 8d 46 ff <c6> 46 ff 00 48 89 45 e0 48 8d 55 e0 48 8d 4d dc 48 8d 75 e8 e8 [ 122.217320] RIP [<ffffffff81228844>] d_absolute_path+0x44/0xa0 [ 122.218860] RSP <ffff880076477b90> [ 122.219919] CR2: ffff880080945fff [ 122.220936] ---[ end trace 506cdbd85eb6c55e ]--- Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: John Johansen <john.johansen@canonical.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
1022 lines
27 KiB
C
1022 lines
27 KiB
C
/*
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* AppArmor security module
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*
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* This file contains AppArmor LSM hooks.
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*
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* Copyright (C) 1998-2008 Novell/SUSE
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* Copyright 2009-2010 Canonical Ltd.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation, version 2 of the
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* License.
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*/
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#include <linux/lsm_hooks.h>
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#include <linux/moduleparam.h>
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#include <linux/mm.h>
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#include <linux/mman.h>
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#include <linux/mount.h>
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#include <linux/namei.h>
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#include <linux/ptrace.h>
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#include <linux/ctype.h>
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#include <linux/sysctl.h>
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#include <linux/audit.h>
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#include <linux/user_namespace.h>
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#include <linux/kmemleak.h>
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#include <net/sock.h>
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#include "include/apparmor.h"
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#include "include/apparmorfs.h"
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#include "include/audit.h"
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#include "include/capability.h"
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#include "include/context.h"
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#include "include/file.h"
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#include "include/ipc.h"
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#include "include/path.h"
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#include "include/policy.h"
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#include "include/policy_ns.h"
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#include "include/procattr.h"
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/* Flag indicating whether initialization completed */
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int apparmor_initialized;
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DEFINE_PER_CPU(struct aa_buffers, aa_buffers);
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/*
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* LSM hook functions
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*/
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/*
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* free the associated aa_task_ctx and put its profiles
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*/
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static void apparmor_cred_free(struct cred *cred)
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{
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aa_free_task_context(cred_ctx(cred));
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cred_ctx(cred) = NULL;
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}
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/*
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* allocate the apparmor part of blank credentials
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*/
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static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
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{
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/* freed by apparmor_cred_free */
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struct aa_task_ctx *ctx = aa_alloc_task_context(gfp);
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if (!ctx)
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return -ENOMEM;
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cred_ctx(cred) = ctx;
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return 0;
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}
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/*
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* prepare new aa_task_ctx for modification by prepare_cred block
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*/
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static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
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gfp_t gfp)
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{
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/* freed by apparmor_cred_free */
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struct aa_task_ctx *ctx = aa_alloc_task_context(gfp);
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if (!ctx)
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return -ENOMEM;
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aa_dup_task_context(ctx, cred_ctx(old));
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cred_ctx(new) = ctx;
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return 0;
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}
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/*
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* transfer the apparmor data to a blank set of creds
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*/
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static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
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{
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const struct aa_task_ctx *old_ctx = cred_ctx(old);
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struct aa_task_ctx *new_ctx = cred_ctx(new);
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aa_dup_task_context(new_ctx, old_ctx);
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}
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static int apparmor_ptrace_access_check(struct task_struct *child,
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unsigned int mode)
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{
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return aa_ptrace(current, child, mode);
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}
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static int apparmor_ptrace_traceme(struct task_struct *parent)
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{
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return aa_ptrace(parent, current, PTRACE_MODE_ATTACH);
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}
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/* Derived from security/commoncap.c:cap_capget */
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static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
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kernel_cap_t *inheritable, kernel_cap_t *permitted)
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{
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struct aa_profile *profile;
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const struct cred *cred;
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rcu_read_lock();
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cred = __task_cred(target);
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profile = aa_cred_profile(cred);
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/*
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* cap_capget is stacked ahead of this and will
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* initialize effective and permitted.
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*/
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if (!unconfined(profile) && !COMPLAIN_MODE(profile)) {
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*effective = cap_intersect(*effective, profile->caps.allow);
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*permitted = cap_intersect(*permitted, profile->caps.allow);
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}
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rcu_read_unlock();
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return 0;
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}
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static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
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int cap, int audit)
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{
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struct aa_profile *profile;
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int error = 0;
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profile = aa_cred_profile(cred);
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if (!unconfined(profile))
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error = aa_capable(profile, cap, audit);
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return error;
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}
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/**
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* common_perm - basic common permission check wrapper fn for paths
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* @op: operation being checked
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* @path: path to check permission of (NOT NULL)
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* @mask: requested permissions mask
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* @cond: conditional info for the permission request (NOT NULL)
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*
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* Returns: %0 else error code if error or permission denied
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*/
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static int common_perm(const char *op, const struct path *path, u32 mask,
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struct path_cond *cond)
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{
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struct aa_profile *profile;
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int error = 0;
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profile = __aa_current_profile();
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if (!unconfined(profile))
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error = aa_path_perm(op, profile, path, 0, mask, cond);
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return error;
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}
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/**
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* common_perm_cond - common permission wrapper around inode cond
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* @op: operation being checked
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* @path: location to check (NOT NULL)
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* @mask: requested permissions mask
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*
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* Returns: %0 else error code if error or permission denied
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*/
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static int common_perm_cond(const char *op, const struct path *path, u32 mask)
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{
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struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
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d_backing_inode(path->dentry)->i_mode
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};
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if (!path_mediated_fs(path->dentry))
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return 0;
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return common_perm(op, path, mask, &cond);
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}
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/**
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* common_perm_dir_dentry - common permission wrapper when path is dir, dentry
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* @op: operation being checked
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* @dir: directory of the dentry (NOT NULL)
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* @dentry: dentry to check (NOT NULL)
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* @mask: requested permissions mask
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* @cond: conditional info for the permission request (NOT NULL)
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*
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* Returns: %0 else error code if error or permission denied
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*/
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static int common_perm_dir_dentry(const char *op, const struct path *dir,
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struct dentry *dentry, u32 mask,
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struct path_cond *cond)
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{
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struct path path = { .mnt = dir->mnt, .dentry = dentry };
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return common_perm(op, &path, mask, cond);
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}
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/**
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* common_perm_rm - common permission wrapper for operations doing rm
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* @op: operation being checked
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* @dir: directory that the dentry is in (NOT NULL)
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* @dentry: dentry being rm'd (NOT NULL)
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* @mask: requested permission mask
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*
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* Returns: %0 else error code if error or permission denied
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*/
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static int common_perm_rm(const char *op, const struct path *dir,
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struct dentry *dentry, u32 mask)
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{
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struct inode *inode = d_backing_inode(dentry);
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struct path_cond cond = { };
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if (!inode || !path_mediated_fs(dentry))
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return 0;
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cond.uid = inode->i_uid;
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cond.mode = inode->i_mode;
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return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
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}
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/**
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* common_perm_create - common permission wrapper for operations doing create
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* @op: operation being checked
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* @dir: directory that dentry will be created in (NOT NULL)
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* @dentry: dentry to create (NOT NULL)
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* @mask: request permission mask
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* @mode: created file mode
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*
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* Returns: %0 else error code if error or permission denied
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*/
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static int common_perm_create(const char *op, const struct path *dir,
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struct dentry *dentry, u32 mask, umode_t mode)
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{
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struct path_cond cond = { current_fsuid(), mode };
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if (!path_mediated_fs(dir->dentry))
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return 0;
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return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
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}
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static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
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{
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return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
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}
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static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
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umode_t mode)
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{
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return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
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S_IFDIR);
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}
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static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
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{
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return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
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}
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static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
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umode_t mode, unsigned int dev)
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{
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return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
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}
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static int apparmor_path_truncate(const struct path *path)
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{
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return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE);
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}
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static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
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const char *old_name)
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{
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return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
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S_IFLNK);
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}
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static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
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struct dentry *new_dentry)
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{
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struct aa_profile *profile;
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int error = 0;
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if (!path_mediated_fs(old_dentry))
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return 0;
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profile = aa_current_profile();
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if (!unconfined(profile))
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error = aa_path_link(profile, old_dentry, new_dir, new_dentry);
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return error;
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}
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static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
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const struct path *new_dir, struct dentry *new_dentry)
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{
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struct aa_profile *profile;
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int error = 0;
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if (!path_mediated_fs(old_dentry))
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return 0;
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profile = aa_current_profile();
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if (!unconfined(profile)) {
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struct path old_path = { .mnt = old_dir->mnt,
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.dentry = old_dentry };
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struct path new_path = { .mnt = new_dir->mnt,
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.dentry = new_dentry };
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struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
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d_backing_inode(old_dentry)->i_mode
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};
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error = aa_path_perm(OP_RENAME_SRC, profile, &old_path, 0,
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MAY_READ | AA_MAY_META_READ | MAY_WRITE |
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AA_MAY_META_WRITE | AA_MAY_DELETE,
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&cond);
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if (!error)
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error = aa_path_perm(OP_RENAME_DEST, profile, &new_path,
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0, MAY_WRITE | AA_MAY_META_WRITE |
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AA_MAY_CREATE, &cond);
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}
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return error;
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}
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static int apparmor_path_chmod(const struct path *path, umode_t mode)
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{
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return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
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}
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static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
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{
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return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
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}
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static int apparmor_inode_getattr(const struct path *path)
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{
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return common_perm_cond(OP_GETATTR, path, AA_MAY_META_READ);
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}
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static int apparmor_file_open(struct file *file, const struct cred *cred)
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{
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struct aa_file_ctx *fctx = file->f_security;
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struct aa_profile *profile;
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int error = 0;
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if (!path_mediated_fs(file->f_path.dentry))
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return 0;
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/* If in exec, permission is handled by bprm hooks.
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* Cache permissions granted by the previous exec check, with
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* implicit read and executable mmap which are required to
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* actually execute the image.
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*/
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if (current->in_execve) {
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fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
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return 0;
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}
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profile = aa_cred_profile(cred);
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if (!unconfined(profile)) {
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struct inode *inode = file_inode(file);
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struct path_cond cond = { inode->i_uid, inode->i_mode };
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error = aa_path_perm(OP_OPEN, profile, &file->f_path, 0,
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aa_map_file_to_perms(file), &cond);
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/* todo cache full allowed permissions set and state */
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fctx->allow = aa_map_file_to_perms(file);
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}
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return error;
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}
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static int apparmor_file_alloc_security(struct file *file)
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{
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/* freed by apparmor_file_free_security */
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file->f_security = aa_alloc_file_context(GFP_KERNEL);
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if (!file->f_security)
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return -ENOMEM;
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return 0;
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}
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static void apparmor_file_free_security(struct file *file)
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{
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struct aa_file_ctx *ctx = file->f_security;
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aa_free_file_context(ctx);
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}
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static int common_file_perm(const char *op, struct file *file, u32 mask)
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{
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struct aa_file_ctx *fctx = file->f_security;
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struct aa_profile *profile, *fprofile = aa_cred_profile(file->f_cred);
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int error = 0;
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AA_BUG(!fprofile);
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if (!file->f_path.mnt ||
|
|
!path_mediated_fs(file->f_path.dentry))
|
|
return 0;
|
|
|
|
profile = __aa_current_profile();
|
|
|
|
/* revalidate access, if task is unconfined, or the cached cred
|
|
* doesn't match or if the request is for more permissions than
|
|
* was granted.
|
|
*
|
|
* Note: the test for !unconfined(fprofile) is to handle file
|
|
* delegation from unconfined tasks
|
|
*/
|
|
if (!unconfined(profile) && !unconfined(fprofile) &&
|
|
((fprofile != profile) || (mask & ~fctx->allow)))
|
|
error = aa_file_perm(op, profile, file, mask);
|
|
|
|
return error;
|
|
}
|
|
|
|
static int apparmor_file_permission(struct file *file, int mask)
|
|
{
|
|
return common_file_perm(OP_FPERM, file, mask);
|
|
}
|
|
|
|
static int apparmor_file_lock(struct file *file, unsigned int cmd)
|
|
{
|
|
u32 mask = AA_MAY_LOCK;
|
|
|
|
if (cmd == F_WRLCK)
|
|
mask |= MAY_WRITE;
|
|
|
|
return common_file_perm(OP_FLOCK, file, mask);
|
|
}
|
|
|
|
static int common_mmap(const char *op, struct file *file, unsigned long prot,
|
|
unsigned long flags)
|
|
{
|
|
int mask = 0;
|
|
|
|
if (!file || !file->f_security)
|
|
return 0;
|
|
|
|
if (prot & PROT_READ)
|
|
mask |= MAY_READ;
|
|
/*
|
|
* Private mappings don't require write perms since they don't
|
|
* write back to the files
|
|
*/
|
|
if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
|
|
mask |= MAY_WRITE;
|
|
if (prot & PROT_EXEC)
|
|
mask |= AA_EXEC_MMAP;
|
|
|
|
return common_file_perm(op, file, mask);
|
|
}
|
|
|
|
static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
|
|
unsigned long prot, unsigned long flags)
|
|
{
|
|
return common_mmap(OP_FMMAP, file, prot, flags);
|
|
}
|
|
|
|
static int apparmor_file_mprotect(struct vm_area_struct *vma,
|
|
unsigned long reqprot, unsigned long prot)
|
|
{
|
|
return common_mmap(OP_FMPROT, vma->vm_file, prot,
|
|
!(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
|
|
}
|
|
|
|
static int apparmor_getprocattr(struct task_struct *task, char *name,
|
|
char **value)
|
|
{
|
|
int error = -ENOENT;
|
|
/* released below */
|
|
const struct cred *cred = get_task_cred(task);
|
|
struct aa_task_ctx *ctx = cred_ctx(cred);
|
|
struct aa_profile *profile = NULL;
|
|
|
|
if (strcmp(name, "current") == 0)
|
|
profile = aa_get_newest_profile(ctx->profile);
|
|
else if (strcmp(name, "prev") == 0 && ctx->previous)
|
|
profile = aa_get_newest_profile(ctx->previous);
|
|
else if (strcmp(name, "exec") == 0 && ctx->onexec)
|
|
profile = aa_get_newest_profile(ctx->onexec);
|
|
else
|
|
error = -EINVAL;
|
|
|
|
if (profile)
|
|
error = aa_getprocattr(profile, value);
|
|
|
|
aa_put_profile(profile);
|
|
put_cred(cred);
|
|
|
|
return error;
|
|
}
|
|
|
|
static int apparmor_setprocattr(const char *name, void *value,
|
|
size_t size)
|
|
{
|
|
char *command, *largs = NULL, *args = value;
|
|
size_t arg_size;
|
|
int error;
|
|
DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR);
|
|
|
|
if (size == 0)
|
|
return -EINVAL;
|
|
|
|
/* AppArmor requires that the buffer must be null terminated atm */
|
|
if (args[size - 1] != '\0') {
|
|
/* null terminate */
|
|
largs = args = kmalloc(size + 1, GFP_KERNEL);
|
|
if (!args)
|
|
return -ENOMEM;
|
|
memcpy(args, value, size);
|
|
args[size] = '\0';
|
|
}
|
|
|
|
error = -EINVAL;
|
|
args = strim(args);
|
|
command = strsep(&args, " ");
|
|
if (!args)
|
|
goto out;
|
|
args = skip_spaces(args);
|
|
if (!*args)
|
|
goto out;
|
|
|
|
arg_size = size - (args - (largs ? largs : (char *) value));
|
|
if (strcmp(name, "current") == 0) {
|
|
if (strcmp(command, "changehat") == 0) {
|
|
error = aa_setprocattr_changehat(args, arg_size,
|
|
!AA_DO_TEST);
|
|
} else if (strcmp(command, "permhat") == 0) {
|
|
error = aa_setprocattr_changehat(args, arg_size,
|
|
AA_DO_TEST);
|
|
} else if (strcmp(command, "changeprofile") == 0) {
|
|
error = aa_change_profile(args, !AA_ONEXEC,
|
|
!AA_DO_TEST, false);
|
|
} else if (strcmp(command, "permprofile") == 0) {
|
|
error = aa_change_profile(args, !AA_ONEXEC, AA_DO_TEST,
|
|
false);
|
|
} else
|
|
goto fail;
|
|
} else if (strcmp(name, "exec") == 0) {
|
|
if (strcmp(command, "exec") == 0)
|
|
error = aa_change_profile(args, AA_ONEXEC, !AA_DO_TEST,
|
|
false);
|
|
else
|
|
goto fail;
|
|
} else
|
|
/* only support the "current" and "exec" process attributes */
|
|
goto fail;
|
|
|
|
if (!error)
|
|
error = size;
|
|
out:
|
|
kfree(largs);
|
|
return error;
|
|
|
|
fail:
|
|
aad(&sa)->profile = aa_current_profile();
|
|
aad(&sa)->info = name;
|
|
aad(&sa)->error = error = -EINVAL;
|
|
aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
|
|
goto out;
|
|
}
|
|
|
|
static int apparmor_task_setrlimit(struct task_struct *task,
|
|
unsigned int resource, struct rlimit *new_rlim)
|
|
{
|
|
struct aa_profile *profile = __aa_current_profile();
|
|
int error = 0;
|
|
|
|
if (!unconfined(profile))
|
|
error = aa_task_setrlimit(profile, task, resource, new_rlim);
|
|
|
|
return error;
|
|
}
|
|
|
|
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),
|
|
LSM_HOOK_INIT(capget, apparmor_capget),
|
|
LSM_HOOK_INIT(capable, apparmor_capable),
|
|
|
|
LSM_HOOK_INIT(path_link, apparmor_path_link),
|
|
LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
|
|
LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
|
|
LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
|
|
LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
|
|
LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
|
|
LSM_HOOK_INIT(path_rename, apparmor_path_rename),
|
|
LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
|
|
LSM_HOOK_INIT(path_chown, apparmor_path_chown),
|
|
LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
|
|
LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
|
|
|
|
LSM_HOOK_INIT(file_open, apparmor_file_open),
|
|
LSM_HOOK_INIT(file_permission, apparmor_file_permission),
|
|
LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
|
|
LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
|
|
LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
|
|
LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
|
|
LSM_HOOK_INIT(file_lock, apparmor_file_lock),
|
|
|
|
LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
|
|
LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
|
|
|
|
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),
|
|
LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
|
|
|
|
LSM_HOOK_INIT(bprm_set_creds, apparmor_bprm_set_creds),
|
|
LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
|
|
LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
|
|
LSM_HOOK_INIT(bprm_secureexec, apparmor_bprm_secureexec),
|
|
|
|
LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
|
|
};
|
|
|
|
/*
|
|
* AppArmor sysfs module parameters
|
|
*/
|
|
|
|
static int param_set_aabool(const char *val, const struct kernel_param *kp);
|
|
static int param_get_aabool(char *buffer, const struct kernel_param *kp);
|
|
#define param_check_aabool param_check_bool
|
|
static const struct kernel_param_ops param_ops_aabool = {
|
|
.flags = KERNEL_PARAM_OPS_FL_NOARG,
|
|
.set = param_set_aabool,
|
|
.get = param_get_aabool
|
|
};
|
|
|
|
static int param_set_aauint(const char *val, const struct kernel_param *kp);
|
|
static int param_get_aauint(char *buffer, const struct kernel_param *kp);
|
|
#define param_check_aauint param_check_uint
|
|
static const struct kernel_param_ops param_ops_aauint = {
|
|
.set = param_set_aauint,
|
|
.get = param_get_aauint
|
|
};
|
|
|
|
static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
|
|
static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
|
|
#define param_check_aalockpolicy param_check_bool
|
|
static const struct kernel_param_ops param_ops_aalockpolicy = {
|
|
.flags = KERNEL_PARAM_OPS_FL_NOARG,
|
|
.set = param_set_aalockpolicy,
|
|
.get = param_get_aalockpolicy
|
|
};
|
|
|
|
static int param_set_audit(const char *val, struct kernel_param *kp);
|
|
static int param_get_audit(char *buffer, struct kernel_param *kp);
|
|
|
|
static int param_set_mode(const char *val, struct kernel_param *kp);
|
|
static int param_get_mode(char *buffer, struct kernel_param *kp);
|
|
|
|
/* Flag values, also controllable via /sys/module/apparmor/parameters
|
|
* We define special types as we want to do additional mediation.
|
|
*/
|
|
|
|
/* AppArmor global enforcement switch - complain, enforce, kill */
|
|
enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
|
|
module_param_call(mode, param_set_mode, param_get_mode,
|
|
&aa_g_profile_mode, S_IRUSR | S_IWUSR);
|
|
|
|
/* whether policy verification hashing is enabled */
|
|
bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
|
|
#ifdef CONFIG_SECURITY_APPARMOR_HASH
|
|
module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
|
|
#endif
|
|
|
|
/* Debug mode */
|
|
bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
|
|
module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
|
|
|
|
/* Audit mode */
|
|
enum audit_mode aa_g_audit;
|
|
module_param_call(audit, param_set_audit, param_get_audit,
|
|
&aa_g_audit, S_IRUSR | S_IWUSR);
|
|
|
|
/* Determines if audit header is included in audited messages. This
|
|
* provides more context if the audit daemon is not running
|
|
*/
|
|
bool aa_g_audit_header = 1;
|
|
module_param_named(audit_header, aa_g_audit_header, aabool,
|
|
S_IRUSR | S_IWUSR);
|
|
|
|
/* lock out loading/removal of policy
|
|
* TODO: add in at boot loading of policy, which is the only way to
|
|
* load policy, if lock_policy is set
|
|
*/
|
|
bool aa_g_lock_policy;
|
|
module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
|
|
S_IRUSR | S_IWUSR);
|
|
|
|
/* Syscall logging mode */
|
|
bool aa_g_logsyscall;
|
|
module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
|
|
|
|
/* Maximum pathname length before accesses will start getting rejected */
|
|
unsigned int aa_g_path_max = 2 * PATH_MAX;
|
|
module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
|
|
|
|
/* Determines how paranoid loading of policy is and how much verification
|
|
* on the loaded policy is done.
|
|
* DEPRECATED: read only as strict checking of load is always done now
|
|
* that none root users (user namespaces) can load policy.
|
|
*/
|
|
bool aa_g_paranoid_load = 1;
|
|
module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
|
|
|
|
/* Boot time disable flag */
|
|
static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
|
|
module_param_named(enabled, apparmor_enabled, bool, S_IRUGO);
|
|
|
|
static int __init apparmor_enabled_setup(char *str)
|
|
{
|
|
unsigned long enabled;
|
|
int error = kstrtoul(str, 0, &enabled);
|
|
if (!error)
|
|
apparmor_enabled = enabled ? 1 : 0;
|
|
return 1;
|
|
}
|
|
|
|
__setup("apparmor=", apparmor_enabled_setup);
|
|
|
|
/* set global flag turning off the ability to load policy */
|
|
static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
|
|
{
|
|
if (!apparmor_enabled)
|
|
return -EINVAL;
|
|
if (apparmor_initialized && !policy_admin_capable(NULL))
|
|
return -EPERM;
|
|
return param_set_bool(val, kp);
|
|
}
|
|
|
|
static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
|
|
{
|
|
if (!apparmor_enabled)
|
|
return -EINVAL;
|
|
if (apparmor_initialized && !policy_view_capable(NULL))
|
|
return -EPERM;
|
|
return param_get_bool(buffer, kp);
|
|
}
|
|
|
|
static int param_set_aabool(const char *val, const struct kernel_param *kp)
|
|
{
|
|
if (!apparmor_enabled)
|
|
return -EINVAL;
|
|
if (apparmor_initialized && !policy_admin_capable(NULL))
|
|
return -EPERM;
|
|
return param_set_bool(val, kp);
|
|
}
|
|
|
|
static int param_get_aabool(char *buffer, const struct kernel_param *kp)
|
|
{
|
|
if (!apparmor_enabled)
|
|
return -EINVAL;
|
|
if (apparmor_initialized && !policy_view_capable(NULL))
|
|
return -EPERM;
|
|
return param_get_bool(buffer, kp);
|
|
}
|
|
|
|
static int param_set_aauint(const char *val, const struct kernel_param *kp)
|
|
{
|
|
if (!apparmor_enabled)
|
|
return -EINVAL;
|
|
if (apparmor_initialized && !policy_admin_capable(NULL))
|
|
return -EPERM;
|
|
return param_set_uint(val, kp);
|
|
}
|
|
|
|
static int param_get_aauint(char *buffer, const struct kernel_param *kp)
|
|
{
|
|
if (!apparmor_enabled)
|
|
return -EINVAL;
|
|
if (apparmor_initialized && !policy_view_capable(NULL))
|
|
return -EPERM;
|
|
return param_get_uint(buffer, kp);
|
|
}
|
|
|
|
static int param_get_audit(char *buffer, struct kernel_param *kp)
|
|
{
|
|
if (!apparmor_enabled)
|
|
return -EINVAL;
|
|
if (apparmor_initialized && !policy_view_capable(NULL))
|
|
return -EPERM;
|
|
return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
|
|
}
|
|
|
|
static int param_set_audit(const char *val, struct kernel_param *kp)
|
|
{
|
|
int i;
|
|
|
|
if (!apparmor_enabled)
|
|
return -EINVAL;
|
|
if (!val)
|
|
return -EINVAL;
|
|
if (apparmor_initialized && !policy_admin_capable(NULL))
|
|
return -EPERM;
|
|
|
|
for (i = 0; i < AUDIT_MAX_INDEX; i++) {
|
|
if (strcmp(val, audit_mode_names[i]) == 0) {
|
|
aa_g_audit = i;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int param_get_mode(char *buffer, struct kernel_param *kp)
|
|
{
|
|
if (!apparmor_enabled)
|
|
return -EINVAL;
|
|
if (apparmor_initialized && !policy_view_capable(NULL))
|
|
return -EPERM;
|
|
|
|
return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
|
|
}
|
|
|
|
static int param_set_mode(const char *val, struct kernel_param *kp)
|
|
{
|
|
int i;
|
|
|
|
if (!apparmor_enabled)
|
|
return -EINVAL;
|
|
if (!val)
|
|
return -EINVAL;
|
|
if (apparmor_initialized && !policy_admin_capable(NULL))
|
|
return -EPERM;
|
|
|
|
for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) {
|
|
if (strcmp(val, aa_profile_mode_names[i]) == 0) {
|
|
aa_g_profile_mode = i;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* AppArmor init functions
|
|
*/
|
|
|
|
/**
|
|
* set_init_ctx - set a task context and profile on the first task.
|
|
*
|
|
* TODO: allow setting an alternate profile than unconfined
|
|
*/
|
|
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);
|
|
if (!ctx)
|
|
return -ENOMEM;
|
|
|
|
ctx->profile = aa_get_profile(root_ns->unconfined);
|
|
cred_ctx(cred) = ctx;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void destroy_buffers(void)
|
|
{
|
|
u32 i, j;
|
|
|
|
for_each_possible_cpu(i) {
|
|
for_each_cpu_buffer(j) {
|
|
kfree(per_cpu(aa_buffers, i).buf[j]);
|
|
per_cpu(aa_buffers, i).buf[j] = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
static int __init alloc_buffers(void)
|
|
{
|
|
u32 i, j;
|
|
|
|
for_each_possible_cpu(i) {
|
|
for_each_cpu_buffer(j) {
|
|
char *buffer;
|
|
|
|
if (cpu_to_node(i) > num_online_nodes())
|
|
/* fallback to kmalloc for offline nodes */
|
|
buffer = kmalloc(aa_g_path_max, GFP_KERNEL);
|
|
else
|
|
buffer = kmalloc_node(aa_g_path_max, GFP_KERNEL,
|
|
cpu_to_node(i));
|
|
if (!buffer) {
|
|
destroy_buffers();
|
|
return -ENOMEM;
|
|
}
|
|
per_cpu(aa_buffers, i).buf[j] = buffer;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
static int apparmor_dointvec(struct ctl_table *table, int write,
|
|
void __user *buffer, size_t *lenp, loff_t *ppos)
|
|
{
|
|
if (!policy_admin_capable(NULL))
|
|
return -EPERM;
|
|
if (!apparmor_enabled)
|
|
return -EINVAL;
|
|
|
|
return proc_dointvec(table, write, buffer, lenp, ppos);
|
|
}
|
|
|
|
static struct ctl_path apparmor_sysctl_path[] = {
|
|
{ .procname = "kernel", },
|
|
{ }
|
|
};
|
|
|
|
static struct ctl_table apparmor_sysctl_table[] = {
|
|
{
|
|
.procname = "unprivileged_userns_apparmor_policy",
|
|
.data = &unprivileged_userns_apparmor_policy,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0600,
|
|
.proc_handler = apparmor_dointvec,
|
|
},
|
|
{ }
|
|
};
|
|
|
|
static int __init apparmor_init_sysctl(void)
|
|
{
|
|
return register_sysctl_paths(apparmor_sysctl_path,
|
|
apparmor_sysctl_table) ? 0 : -ENOMEM;
|
|
}
|
|
#else
|
|
static inline int apparmor_init_sysctl(void)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_SYSCTL */
|
|
|
|
static int __init apparmor_init(void)
|
|
{
|
|
int error;
|
|
|
|
if (!apparmor_enabled || !security_module_enable("apparmor")) {
|
|
aa_info_message("AppArmor disabled by boot time parameter");
|
|
apparmor_enabled = 0;
|
|
return 0;
|
|
}
|
|
|
|
error = aa_setup_dfa_engine();
|
|
if (error) {
|
|
AA_ERROR("Unable to setup dfa engine\n");
|
|
goto alloc_out;
|
|
}
|
|
|
|
error = aa_alloc_root_ns();
|
|
if (error) {
|
|
AA_ERROR("Unable to allocate default profile namespace\n");
|
|
goto alloc_out;
|
|
}
|
|
|
|
error = apparmor_init_sysctl();
|
|
if (error) {
|
|
AA_ERROR("Unable to register sysctls\n");
|
|
goto alloc_out;
|
|
|
|
}
|
|
|
|
error = alloc_buffers();
|
|
if (error) {
|
|
AA_ERROR("Unable to allocate work buffers\n");
|
|
goto buffers_out;
|
|
}
|
|
|
|
error = set_init_ctx();
|
|
if (error) {
|
|
AA_ERROR("Failed to set context on init task\n");
|
|
aa_free_root_ns();
|
|
goto buffers_out;
|
|
}
|
|
security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
|
|
"apparmor");
|
|
|
|
/* Report that AppArmor successfully initialized */
|
|
apparmor_initialized = 1;
|
|
if (aa_g_profile_mode == APPARMOR_COMPLAIN)
|
|
aa_info_message("AppArmor initialized: complain mode enabled");
|
|
else if (aa_g_profile_mode == APPARMOR_KILL)
|
|
aa_info_message("AppArmor initialized: kill mode enabled");
|
|
else
|
|
aa_info_message("AppArmor initialized");
|
|
|
|
return error;
|
|
|
|
buffers_out:
|
|
destroy_buffers();
|
|
|
|
alloc_out:
|
|
aa_destroy_aafs();
|
|
aa_teardown_dfa_engine();
|
|
|
|
apparmor_enabled = 0;
|
|
return error;
|
|
}
|
|
|
|
security_initcall(apparmor_init);
|