linux/security, branch v3.16

Merge branch 'serge-next-2' of git://git.kernel.org/pub/scm/linux/kernel/git/sergeh/linux-security

2014-06-13T14:39:39Z

Pull more security layer updates from Serge Hallyn: "A few more commits had previously failed to make it through security-next into linux-next but this week made it into linux-next. At least commit "ima: introduce ima_kernel_read()" was deemed critical by Mimi to make this merge window. This is a temporary tree just for this request. Mimi has pointed me to some previous threads about keeping maintainer trees at the previous release, which I'll certainly do for anything long-term, after talking with James" * 'serge-next-2' of git://git.kernel.org/pub/scm/linux/kernel/git/sergeh/linux-security: ima: introduce ima_kernel_read() evm: prohibit userspace writing 'security.evm' HMAC value ima: check inode integrity cache in violation check ima: prevent unnecessary policy checking evm: provide option to protect additional SMACK xattrs evm: replace HMAC version with attribute mask ima: prevent new digsig xattr from being replaced

ima: introduce ima_kernel_read()

2014-06-12T21:58:08Z

Commit 8aac62706 "move exit_task_namespaces() outside of exit_notify" introduced the kernel opps since the kernel v3.10, which happens when Apparmor and IMA-appraisal are enabled at the same time. ---------------------------------------------------------------------- [ 106.750167] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 [ 106.750221] IP: [] our_mnt+0x1a/0x30 [ 106.750241] PGD 0 [ 106.750254] Oops: 0000 [#1] SMP [ 106.750272] Modules linked in: cuse parport_pc ppdev bnep rfcomm bluetooth rpcsec_gss_krb5 nfsd auth_rpcgss nfs_acl nfs lockd sunrpc fscache dm_crypt intel_rapl x86_pkg_temp_thermal intel_powerclamp kvm_intel snd_hda_codec_hdmi kvm crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 glue_helper lrw gf128mul ablk_helper cryptd snd_hda_codec_realtek dcdbas snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_seq_midi snd_seq_midi_event snd_rawmidi psmouse snd_seq microcode serio_raw snd_timer snd_seq_device snd soundcore video lpc_ich coretemp mac_hid lp parport mei_me mei nbd hid_generic e1000e usbhid ahci ptp hid libahci pps_core [ 106.750658] CPU: 6 PID: 1394 Comm: mysqld Not tainted 3.13.0-rc7-kds+ #15 [ 106.750673] Hardware name: Dell Inc. OptiPlex 9010/0M9KCM, BIOS A08 09/19/2012 [ 106.750689] task: ffff8800de804920 ti: ffff880400fca000 task.ti: ffff880400fca000 [ 106.750704] RIP: 0010:[] [] our_mnt+0x1a/0x30 [ 106.750725] RSP: 0018:ffff880400fcba60 EFLAGS: 00010286 [ 106.750738] RAX: 0000000000000000 RBX: 0000000000000100 RCX: ffff8800d51523e7 [ 106.750764] RDX: ffffffffffffffea RSI: ffff880400fcba34 RDI: ffff880402d20020 [ 106.750791] RBP: ffff880400fcbae0 R08: 0000000000000000 R09: 0000000000000001 [ 106.750817] R10: 0000000000000000 R11: 0000000000000001 R12: ffff8800d5152300 [ 106.750844] R13: ffff8803eb8df510 R14: ffff880400fcbb28 R15: ffff8800d51523e7 [ 106.750871] FS: 0000000000000000(0000) GS:ffff88040d200000(0000) knlGS:0000000000000000 [ 106.750910] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 106.750935] CR2: 0000000000000018 CR3: 0000000001c0e000 CR4: 00000000001407e0 [ 106.750962] Stack: [ 106.750981] ffffffff813434eb ffff880400fcbb20 ffff880400fcbb18 0000000000000000 [ 106.751037] ffff8800de804920 ffffffff8101b9b9 0001800000000000 0000000000000100 [ 106.751093] 0000010000000000 0000000000000002 000000000000000e ffff8803eb8df500 [ 106.751149] Call Trace: [ 106.751172] [] ? aa_path_name+0x2ab/0x430 [ 106.751199] [] ? sched_clock+0x9/0x10 [ 106.751225] [] aa_path_perm+0x7d/0x170 [ 106.751250] [] ? native_sched_clock+0x15/0x80 [ 106.751276] [] aa_file_perm+0x33/0x40 [ 106.751301] [] common_file_perm+0x8e/0xb0 [ 106.751327] [] apparmor_file_permission+0x18/0x20 [ 106.751355] [] security_file_permission+0x23/0xa0 [ 106.751382] [] rw_verify_area+0x52/0xe0 [ 106.751407] [] vfs_read+0x6d/0x170 [ 106.751432] [] kernel_read+0x41/0x60 [ 106.751457] [] ima_calc_file_hash+0x225/0x280 [ 106.751483] [] ? ima_calc_file_hash+0x32/0x280 [ 106.751509] [] ima_collect_measurement+0x9d/0x160 [ 106.751536] [] ? trace_hardirqs_on+0xd/0x10 [ 106.751562] [] ? ima_file_free+0x6c/0xd0 [ 106.751587] [] ima_update_xattr+0x34/0x60 [ 106.751612] [] ima_file_free+0xc0/0xd0 [ 106.751637] [] __fput+0xd5/0x300 [ 106.751662] [] ____fput+0xe/0x10 [ 106.751687] [] task_work_run+0xc4/0xe0 [ 106.751712] [] do_exit+0x2bd/0xa90 [ 106.751738] [] ? retint_swapgs+0x13/0x1b [ 106.751763] [] do_group_exit+0x4c/0xc0 [ 106.751788] [] SyS_exit_group+0x14/0x20 [ 106.751814] [] system_call_fastpath+0x1a/0x1f [ 106.751839] Code: c3 0f 1f 44 00 00 55 48 89 e5 e8 22 fe ff ff 5d c3 0f 1f 44 00 00 55 65 48 8b 04 25 c0 c9 00 00 48 8b 80 28 06 00 00 48 89 e5 5d <48> 8b 40 18 48 39 87 c0 00 00 00 0f 94 c0 c3 0f 1f 80 00 00 00 [ 106.752185] RIP [] our_mnt+0x1a/0x30 [ 106.752214] RSP [ 106.752236] CR2: 0000000000000018 [ 106.752258] ---[ end trace 3c520748b4732721 ]--- ---------------------------------------------------------------------- The reason for the oops is that IMA-appraisal uses "kernel_read()" when file is closed. kernel_read() honors LSM security hook which calls Apparmor handler, which uses current->nsproxy->mnt_ns. The 'guilty' commit changed the order of cleanup code so that nsproxy->mnt_ns was not already available for Apparmor. Discussion about the issue with Al Viro and Eric W. Biederman suggested that kernel_read() is too high-level for IMA. Another issue, except security checking, that was identified is mandatory locking. kernel_read honors it as well and it might prevent IMA from calculating necessary hash. It was suggested to use simplified version of the function without security and locking checks. This patch introduces special version ima_kernel_read(), which skips security and mandatory locking checking. It prevents the kernel oops to happen. Signed-off-by: Dmitry Kasatkin Suggested-by: Eric W. Biederman Signed-off-by: Mimi Zohar Cc:

evm: prohibit userspace writing 'security.evm' HMAC value

2014-06-12T21:58:07Z

Calculating the 'security.evm' HMAC value requires access to the EVM encrypted key. Only the kernel should have access to it. This patch prevents userspace tools(eg. setfattr, cp --preserve=xattr) from setting/modifying the 'security.evm' HMAC value directly. Signed-off-by: Mimi Zohar Cc:

ima: check inode integrity cache in violation check

2014-06-12T21:58:07Z

When IMA did not support ima-appraisal, existance of the S_IMA flag clearly indicated that the file was measured. With IMA appraisal S_IMA flag indicates that file was measured and/or appraised. Because of this, when measurement is not enabled by the policy, violations are still reported. To differentiate between measurement and appraisal policies this patch checks the inode integrity cache flags. The IMA_MEASURED flag indicates whether the file was actually measured, while the IMA_MEASURE flag indicates whether the file should be measured. Unfortunately, the IMA_MEASURED flag is reset to indicate the file needs to be re-measured. Thus, this patch checks the IMA_MEASURE flag. This patch limits the false positive violation reports, but does not fix it entirely. The IMA_MEASURE/IMA_MEASURED flags are indications that, at some point in time, the file opened for read was in policy, but might not be in policy now (eg. different uid). Other changes would be needed to further limit false positive violation reports. Changelog: - expanded patch description based on conversation with Roberto (Mimi) Signed-off-by: Dmitry Kasatkin Signed-off-by: Mimi Zohar

ima: prevent unnecessary policy checking

2014-06-12T21:58:06Z

ima_rdwr_violation_check is called for every file openning. The function checks the policy even when violation condition is not met. It causes unnecessary policy checking. This patch does policy checking only if violation condition is met. Changelog: - check writecount is greater than zero (Mimi) Signed-off-by: Dmitry Kasatkin Signed-off-by: Mimi Zohar

evm: provide option to protect additional SMACK xattrs

2014-06-12T21:58:06Z

Newer versions of SMACK introduced following security xattrs: SMACK64EXEC, SMACK64TRANSMUTE and SMACK64MMAP. To protect these xattrs, this patch includes them in the HMAC calculation. However, for backwards compatibility with existing labeled filesystems, including these xattrs needs to be configurable. Changelog: - Add SMACK dependency on new option (Mimi) Signed-off-by: Dmitry Kasatkin Signed-off-by: Mimi Zohar

evm: replace HMAC version with attribute mask

2014-06-12T21:58:06Z

Using HMAC version limits the posibility to arbitrarily add new attributes such as SMACK64EXEC to the hmac calculation. This patch replaces hmac version with attribute mask. Desired attributes can be enabled with configuration parameter. It allows to build kernels which works with previously labeled filesystems. Currently supported attribute is 'fsuuid' which is equivalent of the former version 2. Signed-off-by: Dmitry Kasatkin Signed-off-by: Mimi Zohar

ima: prevent new digsig xattr from being replaced

2014-06-12T21:58:05Z

Even though a new xattr will only be appraised on the next access, set the DIGSIG flag to prevent a signature from being replaced with a hash on file close. Signed-off-by: Mimi Zohar

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2014-06-12T21:27:40Z

Pull networking updates from David Miller: 1) Seccomp BPF filters can now be JIT'd, from Alexei Starovoitov. 2) Multiqueue support in xen-netback and xen-netfront, from Andrew J Benniston. 3) Allow tweaking of aggregation settings in cdc_ncm driver, from Bjørn Mork. 4) BPF now has a "random" opcode, from Chema Gonzalez. 5) Add more BPF documentation and improve test framework, from Daniel Borkmann. 6) Support TCP fastopen over ipv6, from Daniel Lee. 7) Add software TSO helper functions and use them to support software TSO in mvneta and mv643xx_eth drivers. From Ezequiel Garcia. 8) Support software TSO in fec driver too, from Nimrod Andy. 9) Add Broadcom SYSTEMPORT driver, from Florian Fainelli. 10) Handle broadcasts more gracefully over macvlan when there are large numbers of interfaces configured, from Herbert Xu. 11) Allow more control over fwmark used for non-socket based responses, from Lorenzo Colitti. 12) Do TCP congestion window limiting based upon measurements, from Neal Cardwell. 13) Support busy polling in SCTP, from Neal Horman. 14) Allow RSS key to be configured via ethtool, from Venkata Duvvuru. 15) Bridge promisc mode handling improvements from Vlad Yasevich. 16) Don't use inetpeer entries to implement ID generation any more, it performs poorly, from Eric Dumazet. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1522 commits) rtnetlink: fix userspace API breakage for iproute2 < v3.9.0 tcp: fixing TLP's FIN recovery net: fec: Add software TSO support net: fec: Add Scatter/gather support net: fec: Increase buffer descriptor entry number net: fec: Factorize feature setting net: fec: Enable IP header hardware checksum net: fec: Factorize the .xmit transmit function bridge: fix compile error when compiling without IPv6 support bridge: fix smatch warning / potential null pointer dereference via-rhine: fix full-duplex with autoneg disable bnx2x: Enlarge the dorq threshold for VFs bnx2x: Check for UNDI in uncommon branch bnx2x: Fix 1G-baseT link bnx2x: Fix link for KR with swapped polarity lane sctp: Fix sk_ack_backlog wrap-around problem net/core: Add VF link state control policy net/fsl: xgmac_mdio is dependent on OF_MDIO net/fsl: Make xgmac_mdio read error message useful net_sched: drr: warn when qdisc is not work conserving ...

Merge branch 'serge-next-1' of git://git.kernel.org/pub/scm/linux/kernel/git/sergeh/linux-security

2014-06-10T17:05:36Z

Pull security layer updates from Serge Hallyn: "This is a merge of James Morris' security-next tree from 3.14 to yesterday's master, plus four patches from Paul Moore which are in linux-next, plus one patch from Mimi" * 'serge-next-1' of git://git.kernel.org/pub/scm/linux/kernel/git/sergeh/linux-security: ima: audit log files opened with O_DIRECT flag selinux: conditionally reschedule in hashtab_insert while loading selinux policy selinux: conditionally reschedule in mls_convert_context while loading selinux policy selinux: reject setexeccon() on MNT_NOSUID applications with -EACCES selinux: Report permissive mode in avc: denied messages. Warning in scanf string typing Smack: Label cgroup files for systemd Smack: Verify read access on file open - v3 security: Convert use of typedef ctl_table to struct ctl_table Smack: bidirectional UDS connect check Smack: Correctly remove SMACK64TRANSMUTE attribute SMACK: Fix handling value==NULL in post setxattr bugfix patch for SMACK Smack: adds smackfs/ptrace interface Smack: unify all ptrace accesses in the smack Smack: fix the subject/object order in smack_ptrace_traceme() Minor improvement of 'smack_sb_kern_mount' smack: fix key permission verification KEYS: Move the flags representing required permission to linux/key.h