linux/security/apparmor/include/audit.h

212 lines
4.9 KiB

apparmor: add mount mediation Add basic mount mediation. That allows controlling based on basic mount parameters. It does not include special mount parameters for apparmor, super block labeling, or any triggers for apparmor namespace parameter modifications on pivot root. default userspace policy rules have the form of MOUNT RULE = ( MOUNT | REMOUNT | UMOUNT ) MOUNT = [ QUALIFIERS ] 'mount' [ MOUNT CONDITIONS ] [ SOURCE FILEGLOB ] [ '->' MOUNTPOINT FILEGLOB ] REMOUNT = [ QUALIFIERS ] 'remount' [ MOUNT CONDITIONS ] MOUNTPOINT FILEGLOB UMOUNT = [ QUALIFIERS ] 'umount' [ MOUNT CONDITIONS ] MOUNTPOINT FILEGLOB MOUNT CONDITIONS = [ ( 'fstype' | 'vfstype' ) ( '=' | 'in' ) MOUNT FSTYPE EXPRESSION ] [ 'options' ( '=' | 'in' ) MOUNT FLAGS EXPRESSION ] MOUNT FSTYPE EXPRESSION = ( MOUNT FSTYPE LIST | MOUNT EXPRESSION ) MOUNT FSTYPE LIST = Comma separated list of valid filesystem and virtual filesystem types (eg ext4, debugfs, etc) MOUNT FLAGS EXPRESSION = ( MOUNT FLAGS LIST | MOUNT EXPRESSION ) MOUNT FLAGS LIST = Comma separated list of MOUNT FLAGS. MOUNT FLAGS = ( 'ro' | 'rw' | 'nosuid' | 'suid' | 'nodev' | 'dev' | 'noexec' | 'exec' | 'sync' | 'async' | 'remount' | 'mand' | 'nomand' | 'dirsync' | 'noatime' | 'atime' | 'nodiratime' | 'diratime' | 'bind' | 'rbind' | 'move' | 'verbose' | 'silent' | 'loud' | 'acl' | 'noacl' | 'unbindable' | 'runbindable' | 'private' | 'rprivate' | 'slave' | 'rslave' | 'shared' | 'rshared' | 'relatime' | 'norelatime' | 'iversion' | 'noiversion' | 'strictatime' | 'nouser' | 'user' ) MOUNT EXPRESSION = ( ALPHANUMERIC | AARE ) ... PIVOT ROOT RULE = [ QUALIFIERS ] pivot_root [ oldroot=OLD PUT FILEGLOB ] [ NEW ROOT FILEGLOB ] SOURCE FILEGLOB = FILEGLOB MOUNTPOINT FILEGLOB = FILEGLOB eg. mount, mount /dev/foo, mount options=ro /dev/foo -> /mnt/, mount options in (ro,atime) /dev/foo -> /mnt/, mount options=ro options=atime, Signed-off-by: John Johansen <john.johansen@canonical.com> Acked-by: Seth Arnold <seth.arnold@canonical.com>
2017-07-18 23:04:47 -07:00
apparmor: fix oops in audit_signal_cb hook The apparmor_audit_data struct ordering got messed up during a merge conflict, resulting in the signal integer and peer pointer being in a union instead of a struct. For most of the 4.13 and 4.14 life cycle, this was hidden by commit 651e28c5537a ("apparmor: add base infastructure for socket mediation") which fixed the apparmor_audit_data struct when its data was added. When that commit was reverted in -rc7 the signal audit bug was exposed, and unfortunately it never showed up in any of the testing until after 4.14 was released. Shaun Khan, Zephaniah E. Loss-Cutler-Hull filed nearly simultaneous bug reports (with different oopes, the smaller of which is included below). Full credit goes to Tetsuo Handa for jumping on this as well and noticing the audit data struct problem and reporting it. [ 76.178568] BUG: unable to handle kernel paging request at ffffffff0eee3bc0 [ 76.178579] IP: audit_signal_cb+0x6c/0xe0 [ 76.178581] PGD 1a640a067 P4D 1a640a067 PUD 0 [ 76.178586] Oops: 0000 [#1] PREEMPT SMP [ 76.178589] Modules linked in: fuse rfcomm bnep usblp uvcvideo btusb btrtl btbcm btintel bluetooth ecdh_generic ip6table_filter ip6_tables xt_tcpudp nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack iptable_filter ip_tables x_tables intel_rapl joydev wmi_bmof serio_raw iwldvm iwlwifi shpchp kvm_intel kvm irqbypass autofs4 algif_skcipher nls_iso8859_1 nls_cp437 crc32_pclmul ghash_clmulni_intel [ 76.178620] CPU: 0 PID: 10675 Comm: pidgin Not tainted 4.14.0-f1-dirty #135 [ 76.178623] Hardware name: Hewlett-Packard HP EliteBook Folio 9470m/18DF, BIOS 68IBD Ver. F.62 10/22/2015 [ 76.178625] task: ffff9c7a94c31dc0 task.stack: ffffa09b02a4c000 [ 76.178628] RIP: 0010:audit_signal_cb+0x6c/0xe0 [ 76.178631] RSP: 0018:ffffa09b02a4fc08 EFLAGS: 00010292 [ 76.178634] RAX: ffffa09b02a4fd60 RBX: ffff9c7aee0741f8 RCX: 0000000000000000 [ 76.178636] RDX: ffffffffee012290 RSI: 0000000000000006 RDI: ffff9c7a9493d800 [ 76.178638] RBP: ffffa09b02a4fd40 R08: 000000000000004d R09: ffffa09b02a4fc46 [ 76.178641] R10: ffffa09b02a4fcb8 R11: ffff9c7ab44f5072 R12: ffffa09b02a4fd40 [ 76.178643] R13: ffffffff9e447be0 R14: ffff9c7a94c31dc0 R15: 0000000000000001 [ 76.178646] FS: 00007f8b11ba2a80(0000) GS:ffff9c7afea00000(0000) knlGS:0000000000000000 [ 76.178648] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 76.178650] CR2: ffffffff0eee3bc0 CR3: 00000003d5209002 CR4: 00000000001606f0 [ 76.178652] Call Trace: [ 76.178660] common_lsm_audit+0x1da/0x780 [ 76.178665] ? d_absolute_path+0x60/0x90 [ 76.178669] ? aa_check_perms+0xcd/0xe0 [ 76.178672] aa_check_perms+0xcd/0xe0 [ 76.178675] profile_signal_perm.part.0+0x90/0xa0 [ 76.178679] aa_may_signal+0x16e/0x1b0 [ 76.178686] apparmor_task_kill+0x51/0x120 [ 76.178690] security_task_kill+0x44/0x60 [ 76.178695] group_send_sig_info+0x25/0x60 [ 76.178699] kill_pid_info+0x36/0x60 [ 76.178703] SYSC_kill+0xdb/0x180 [ 76.178707] ? preempt_count_sub+0x92/0xd0 [ 76.178712] ? _raw_write_unlock_irq+0x13/0x30 [ 76.178716] ? task_work_run+0x6a/0x90 [ 76.178720] ? exit_to_usermode_loop+0x80/0xa0 [ 76.178723] entry_SYSCALL_64_fastpath+0x13/0x94 [ 76.178727] RIP: 0033:0x7f8b0e58b767 [ 76.178729] RSP: 002b:00007fff19efd4d8 EFLAGS: 00000206 ORIG_RAX: 000000000000003e [ 76.178732] RAX: ffffffffffffffda RBX: 0000557f3e3c2050 RCX: 00007f8b0e58b767 [ 76.178735] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000263b [ 76.178737] RBP: 0000000000000000 R08: 0000557f3e3c2270 R09: 0000000000000001 [ 76.178739] R10: 000000000000022d R11: 0000000000000206 R12: 0000000000000000 [ 76.178741] R13: 0000000000000001 R14: 0000557f3e3c13c0 R15: 0000000000000000 [ 76.178745] Code: 48 8b 55 18 48 89 df 41 b8 20 00 08 01 5b 5d 48 8b 42 10 48 8b 52 30 48 63 48 4c 48 8b 44 c8 48 31 c9 48 8b 70 38 e9 f4 fd 00 00 <48> 8b 14 d5 40 27 e5 9e 48 c7 c6 7d 07 19 9f 48 89 df e8 fd 35 [ 76.178794] RIP: audit_signal_cb+0x6c/0xe0 RSP: ffffa09b02a4fc08 [ 76.178796] CR2: ffffffff0eee3bc0 [ 76.178799] ---[ end trace 514af9529297f1a3 ]--- Fixes: cd1dbf76b23d ("apparmor: add the ability to mediate signals") Reported-by: Zephaniah E. Loss-Cutler-Hull <warp-spam_kernel@aehallh.com> Reported-by: Shuah Khan <shuahkh@osg.samsung.com> Suggested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Tested-by: Ivan Kozik <ivan@ludios.org> Tested-by: Zephaniah E. Loss-Cutler-Hull <warp-spam_kernel@aehallh.com> Tested-by: Christian Boltz <apparmor@cboltz.de> Tested-by: Shuah Khan <shuahkh@osg.samsung.com> Cc: stable@vger.kernel.org Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-11-22 07:33:38 -08:00
apparmor: fix oops in audit_signal_cb hook The apparmor_audit_data struct ordering got messed up during a merge conflict, resulting in the signal integer and peer pointer being in a union instead of a struct. For most of the 4.13 and 4.14 life cycle, this was hidden by commit 651e28c5537a ("apparmor: add base infastructure for socket mediation") which fixed the apparmor_audit_data struct when its data was added. When that commit was reverted in -rc7 the signal audit bug was exposed, and unfortunately it never showed up in any of the testing until after 4.14 was released. Shaun Khan, Zephaniah E. Loss-Cutler-Hull filed nearly simultaneous bug reports (with different oopes, the smaller of which is included below). Full credit goes to Tetsuo Handa for jumping on this as well and noticing the audit data struct problem and reporting it. [ 76.178568] BUG: unable to handle kernel paging request at ffffffff0eee3bc0 [ 76.178579] IP: audit_signal_cb+0x6c/0xe0 [ 76.178581] PGD 1a640a067 P4D 1a640a067 PUD 0 [ 76.178586] Oops: 0000 [#1] PREEMPT SMP [ 76.178589] Modules linked in: fuse rfcomm bnep usblp uvcvideo btusb btrtl btbcm btintel bluetooth ecdh_generic ip6table_filter ip6_tables xt_tcpudp nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack iptable_filter ip_tables x_tables intel_rapl joydev wmi_bmof serio_raw iwldvm iwlwifi shpchp kvm_intel kvm irqbypass autofs4 algif_skcipher nls_iso8859_1 nls_cp437 crc32_pclmul ghash_clmulni_intel [ 76.178620] CPU: 0 PID: 10675 Comm: pidgin Not tainted 4.14.0-f1-dirty #135 [ 76.178623] Hardware name: Hewlett-Packard HP EliteBook Folio 9470m/18DF, BIOS 68IBD Ver. F.62 10/22/2015 [ 76.178625] task: ffff9c7a94c31dc0 task.stack: ffffa09b02a4c000 [ 76.178628] RIP: 0010:audit_signal_cb+0x6c/0xe0 [ 76.178631] RSP: 0018:ffffa09b02a4fc08 EFLAGS: 00010292 [ 76.178634] RAX: ffffa09b02a4fd60 RBX: ffff9c7aee0741f8 RCX: 0000000000000000 [ 76.178636] RDX: ffffffffee012290 RSI: 0000000000000006 RDI: ffff9c7a9493d800 [ 76.178638] RBP: ffffa09b02a4fd40 R08: 000000000000004d R09: ffffa09b02a4fc46 [ 76.178641] R10: ffffa09b02a4fcb8 R11: ffff9c7ab44f5072 R12: ffffa09b02a4fd40 [ 76.178643] R13: ffffffff9e447be0 R14: ffff9c7a94c31dc0 R15: 0000000000000001 [ 76.178646] FS: 00007f8b11ba2a80(0000) GS:ffff9c7afea00000(0000) knlGS:0000000000000000 [ 76.178648] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 76.178650] CR2: ffffffff0eee3bc0 CR3: 00000003d5209002 CR4: 00000000001606f0 [ 76.178652] Call Trace: [ 76.178660] common_lsm_audit+0x1da/0x780 [ 76.178665] ? d_absolute_path+0x60/0x90 [ 76.178669] ? aa_check_perms+0xcd/0xe0 [ 76.178672] aa_check_perms+0xcd/0xe0 [ 76.178675] profile_signal_perm.part.0+0x90/0xa0 [ 76.178679] aa_may_signal+0x16e/0x1b0 [ 76.178686] apparmor_task_kill+0x51/0x120 [ 76.178690] security_task_kill+0x44/0x60 [ 76.178695] group_send_sig_info+0x25/0x60 [ 76.178699] kill_pid_info+0x36/0x60 [ 76.178703] SYSC_kill+0xdb/0x180 [ 76.178707] ? preempt_count_sub+0x92/0xd0 [ 76.178712] ? _raw_write_unlock_irq+0x13/0x30 [ 76.178716] ? task_work_run+0x6a/0x90 [ 76.178720] ? exit_to_usermode_loop+0x80/0xa0 [ 76.178723] entry_SYSCALL_64_fastpath+0x13/0x94 [ 76.178727] RIP: 0033:0x7f8b0e58b767 [ 76.178729] RSP: 002b:00007fff19efd4d8 EFLAGS: 00000206 ORIG_RAX: 000000000000003e [ 76.178732] RAX: ffffffffffffffda RBX: 0000557f3e3c2050 RCX: 00007f8b0e58b767 [ 76.178735] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000263b [ 76.178737] RBP: 0000000000000000 R08: 0000557f3e3c2270 R09: 0000000000000001 [ 76.178739] R10: 000000000000022d R11: 0000000000000206 R12: 0000000000000000 [ 76.178741] R13: 0000000000000001 R14: 0000557f3e3c13c0 R15: 0000000000000000 [ 76.178745] Code: 48 8b 55 18 48 89 df 41 b8 20 00 08 01 5b 5d 48 8b 42 10 48 8b 52 30 48 63 48 4c 48 8b 44 c8 48 31 c9 48 8b 70 38 e9 f4 fd 00 00 <48> 8b 14 d5 40 27 e5 9e 48 c7 c6 7d 07 19 9f 48 89 df e8 fd 35 [ 76.178794] RIP: audit_signal_cb+0x6c/0xe0 RSP: ffffa09b02a4fc08 [ 76.178796] CR2: ffffffff0eee3bc0 [ 76.178799] ---[ end trace 514af9529297f1a3 ]--- Fixes: cd1dbf76b23d ("apparmor: add the ability to mediate signals") Reported-by: Zephaniah E. Loss-Cutler-Hull <warp-spam_kernel@aehallh.com> Reported-by: Shuah Khan <shuahkh@osg.samsung.com> Suggested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Tested-by: Ivan Kozik <ivan@ludios.org> Tested-by: Zephaniah E. Loss-Cutler-Hull <warp-spam_kernel@aehallh.com> Tested-by: Christian Boltz <apparmor@cboltz.de> Tested-by: Shuah Khan <shuahkh@osg.samsung.com> Cc: stable@vger.kernel.org Signed-off-by: John Johansen <john.johansen@canonical.com>
2017-11-22 07:33:38 -08:00
apparmor: add mount mediation Add basic mount mediation. That allows controlling based on basic mount parameters. It does not include special mount parameters for apparmor, super block labeling, or any triggers for apparmor namespace parameter modifications on pivot root. default userspace policy rules have the form of MOUNT RULE = ( MOUNT | REMOUNT | UMOUNT ) MOUNT = [ QUALIFIERS ] 'mount' [ MOUNT CONDITIONS ] [ SOURCE FILEGLOB ] [ '->' MOUNTPOINT FILEGLOB ] REMOUNT = [ QUALIFIERS ] 'remount' [ MOUNT CONDITIONS ] MOUNTPOINT FILEGLOB UMOUNT = [ QUALIFIERS ] 'umount' [ MOUNT CONDITIONS ] MOUNTPOINT FILEGLOB MOUNT CONDITIONS = [ ( 'fstype' | 'vfstype' ) ( '=' | 'in' ) MOUNT FSTYPE EXPRESSION ] [ 'options' ( '=' | 'in' ) MOUNT FLAGS EXPRESSION ] MOUNT FSTYPE EXPRESSION = ( MOUNT FSTYPE LIST | MOUNT EXPRESSION ) MOUNT FSTYPE LIST = Comma separated list of valid filesystem and virtual filesystem types (eg ext4, debugfs, etc) MOUNT FLAGS EXPRESSION = ( MOUNT FLAGS LIST | MOUNT EXPRESSION ) MOUNT FLAGS LIST = Comma separated list of MOUNT FLAGS. MOUNT FLAGS = ( 'ro' | 'rw' | 'nosuid' | 'suid' | 'nodev' | 'dev' | 'noexec' | 'exec' | 'sync' | 'async' | 'remount' | 'mand' | 'nomand' | 'dirsync' | 'noatime' | 'atime' | 'nodiratime' | 'diratime' | 'bind' | 'rbind' | 'move' | 'verbose' | 'silent' | 'loud' | 'acl' | 'noacl' | 'unbindable' | 'runbindable' | 'private' | 'rprivate' | 'slave' | 'rslave' | 'shared' | 'rshared' | 'relatime' | 'norelatime' | 'iversion' | 'noiversion' | 'strictatime' | 'nouser' | 'user' ) MOUNT EXPRESSION = ( ALPHANUMERIC | AARE ) ... PIVOT ROOT RULE = [ QUALIFIERS ] pivot_root [ oldroot=OLD PUT FILEGLOB ] [ NEW ROOT FILEGLOB ] SOURCE FILEGLOB = FILEGLOB MOUNTPOINT FILEGLOB = FILEGLOB eg. mount, mount /dev/foo, mount options=ro /dev/foo -> /mnt/, mount options in (ro,atime) /dev/foo -> /mnt/, mount options=ro options=atime, Signed-off-by: John Johansen <john.johansen@canonical.com> Acked-by: Seth Arnold <seth.arnold@canonical.com>
2017-07-18 23:04:47 -07:00
ima: Avoid blocking in RCU read-side critical section A panic happens in ima_match_policy: BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 PGD 42f873067 P4D 0 Oops: 0000 [#1] SMP NOPTI CPU: 5 PID: 1286325 Comm: kubeletmonit.sh Kdump: loaded Tainted: P Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 RIP: 0010:ima_match_policy+0x84/0x450 Code: 49 89 fc 41 89 cf 31 ed 89 44 24 14 eb 1c 44 39 7b 18 74 26 41 83 ff 05 74 20 48 8b 1b 48 3b 1d f2 b9 f4 00 0f 84 9c 01 00 00 <44> 85 73 10 74 ea 44 8b 6b 14 41 f6 c5 01 75 d4 41 f6 c5 02 74 0f RSP: 0018:ff71570009e07a80 EFLAGS: 00010207 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000200 RDX: ffffffffad8dc7c0 RSI: 0000000024924925 RDI: ff3e27850dea2000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffffabfce739 R10: ff3e27810cc42400 R11: 0000000000000000 R12: ff3e2781825ef970 R13: 00000000ff3e2785 R14: 000000000000000c R15: 0000000000000001 FS: 00007f5195b51740(0000) GS:ff3e278b12d40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000010 CR3: 0000000626d24002 CR4: 0000000000361ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ima_get_action+0x22/0x30 process_measurement+0xb0/0x830 ? page_add_file_rmap+0x15/0x170 ? alloc_set_pte+0x269/0x4c0 ? prep_new_page+0x81/0x140 ? simple_xattr_get+0x75/0xa0 ? selinux_file_open+0x9d/0xf0 ima_file_check+0x64/0x90 path_openat+0x571/0x1720 do_filp_open+0x9b/0x110 ? page_counter_try_charge+0x57/0xc0 ? files_cgroup_alloc_fd+0x38/0x60 ? __alloc_fd+0xd4/0x250 ? do_sys_open+0x1bd/0x250 do_sys_open+0x1bd/0x250 do_syscall_64+0x5d/0x1d0 entry_SYSCALL_64_after_hwframe+0x65/0xca Commit c7423dbdbc9e ("ima: Handle -ESTALE returned by ima_filter_rule_match()") introduced call to ima_lsm_copy_rule within a RCU read-side critical section which contains kmalloc with GFP_KERNEL. This implies a possible sleep and violates limitations of RCU read-side critical sections on non-PREEMPT systems. Sleeping within RCU read-side critical section might cause synchronize_rcu() returning early and break RCU protection, allowing a UAF to happen. The root cause of this issue could be described as follows: | Thread A | Thread B | | |ima_match_policy | | | rcu_read_lock | |ima_lsm_update_rule | | | synchronize_rcu | | | | kmalloc(GFP_KERNEL)| | | sleep | ==> synchronize_rcu returns early | kfree(entry) | | | | entry = entry->next| ==> UAF happens and entry now becomes NULL (or could be anything). | | entry->action | ==> Accessing entry might cause panic. To fix this issue, we are converting all kmalloc that is called within RCU read-side critical section to use GFP_ATOMIC. Fixes: c7423dbdbc9e ("ima: Handle -ESTALE returned by ima_filter_rule_match()") Cc: stable@vger.kernel.org Signed-off-by: GUO Zihua <guozihua@huawei.com> Acked-by: John Johansen <john.johansen@canonical.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> [PM: fixed missing comment, long lines, !CONFIG_IMA_LSM_RULES case] Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-05-07 01:25:41 +00:00