Commit Graph

26 Commits

Author SHA1 Message Date
Mimi Zohar 02897ed9ec integrity: double check iint_cache was initialized
commit 92063f3ca73aab794bd5408d3361fd5b5ea33079 upstream.

The kernel may be built with multiple LSMs, but only a subset may be
enabled on the boot command line by specifying "lsm=".  Not including
"integrity" on the ordered LSM list may result in a NULL deref.

As reported by Dmitry Vyukov:
in qemu:
qemu-system-x86_64       -enable-kvm     -machine q35,nvdimm -cpu
max,migratable=off -smp 4       -m 4G,slots=4,maxmem=16G        -hda
wheezy.img      -kernel arch/x86/boot/bzImage   -nographic -vga std
 -soundhw all     -usb -usbdevice tablet  -bt hci -bt device:keyboard
   -net user,host=10.0.2.10,hostfwd=tcp::10022-:22 -net
nic,model=virtio-net-pci   -object
memory-backend-file,id=pmem1,share=off,mem-path=/dev/zero,size=64M
  -device nvdimm,id=nvdimm1,memdev=pmem1  -append "console=ttyS0
root=/dev/sda earlyprintk=serial rodata=n oops=panic panic_on_warn=1
panic=86400 lsm=smack numa=fake=2 nopcid dummy_hcd.num=8"   -pidfile
vm_pid -m 2G -cpu host

But it crashes on NULL deref in integrity_inode_get during boot:

Run /sbin/init as init process
BUG: kernel NULL pointer dereference, address: 000000000000001c
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.12.0-rc2+ #97
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
rel-1.13.0-44-g88ab0c15525c-prebuilt.qemu.org 04/01/2014
RIP: 0010:kmem_cache_alloc+0x2b/0x370 mm/slub.c:2920
Code: 57 41 56 41 55 41 54 41 89 f4 55 48 89 fd 53 48 83 ec 10 44 8b
3d d9 1f 90 0b 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 31 c0 <8b> 5f
1c 4cf
RSP: 0000:ffffc9000032f9d8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888017fc4f00 RCX: 0000000000000000
RDX: ffff888040220000 RSI: 0000000000000c40 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffff888019263627
R10: ffffffff83937cd1 R11: 0000000000000000 R12: 0000000000000c40
R13: ffff888019263538 R14: 0000000000000000 R15: 0000000000ffffff
FS:  0000000000000000(0000) GS:ffff88802d180000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000001c CR3: 000000000b48e000 CR4: 0000000000750ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 integrity_inode_get+0x47/0x260 security/integrity/iint.c:105
 process_measurement+0x33d/0x17e0 security/integrity/ima/ima_main.c:237
 ima_bprm_check+0xde/0x210 security/integrity/ima/ima_main.c:474
 security_bprm_check+0x7d/0xa0 security/security.c:845
 search_binary_handler fs/exec.c:1708 [inline]
 exec_binprm fs/exec.c:1761 [inline]
 bprm_execve fs/exec.c:1830 [inline]
 bprm_execve+0x764/0x19a0 fs/exec.c:1792
 kernel_execve+0x370/0x460 fs/exec.c:1973
 try_to_run_init_process+0x14/0x4e init/main.c:1366
 kernel_init+0x11d/0x1b8 init/main.c:1477
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Modules linked in:
CR2: 000000000000001c
---[ end trace 22d601a500de7d79 ]---

Since LSMs and IMA may be configured at build time, but not enabled at
run time, panic the system if "integrity" was not initialized before use.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Fixes: 79f7865d844c ("LSM: Introduce "lsm=" for boottime LSM selection")
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-12 12:53:26 +08:00
David Howells dd58eb0103 certs: Fix blacklist flag type confusion
[ Upstream commit 4993e1f9479a4161fd7d93e2b8b30b438f00cb0f ]

KEY_FLAG_KEEP is not meant to be passed to keyring_alloc() or key_alloc(),
as these only take KEY_ALLOC_* flags.  KEY_FLAG_KEEP has the same value as
KEY_ALLOC_BYPASS_RESTRICTION, but fortunately only key_create_or_update()
uses it.  LSMs using the key_alloc hook don't check that flag.

KEY_FLAG_KEEP is then ignored but fortunately (again) the root user cannot
write to the blacklist keyring, so it is not possible to remove a key/hash
from it.

Fix this by adding a KEY_ALLOC_SET_KEEP flag that tells key_alloc() to set
KEY_FLAG_KEEP on the new key.  blacklist_init() can then, correctly, pass
this to keyring_alloc().

We can also use this in ima_mok_init() rather than setting the flag
manually.

Note that this doesn't fix an observable bug with the current
implementation but it is required to allow addition of new hashes to the
blacklist in the future without making it possible for them to be removed.

Fixes: 734114f8782f ("KEYS: Add a system blacklist keyring")
Reported-by: Mickaël Salaün <mic@linux.microsoft.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Mickaël Salaün <mic@linux.microsoft.com>
cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-12 12:52:25 +08:00
Lakshmi Ramasubramanian 317e4b2030 ima: Free IMA measurement buffer after kexec syscall
[ Upstream commit f31e3386a4e92ba6eda7328cb508462956c94c64 ]

IMA allocates kernel virtual memory to carry forward the measurement
list, from the current kernel to the next kernel on kexec system call,
in ima_add_kexec_buffer() function.  This buffer is not freed before
completing the kexec system call resulting in memory leak.

Add ima_buffer field in "struct kimage" to store the virtual address
of the buffer allocated for the IMA measurement list.
Free the memory allocated for the IMA measurement list in
kimage_file_post_load_cleanup() function.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Fixes: 7b8589cc29e7 ("ima: on soft reboot, save the measurement list")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-12 12:52:21 +08:00
Lakshmi Ramasubramanian bd78cec3a5 ima: Free IMA measurement buffer on error
[ Upstream commit 6d14c6517885fa68524238787420511b87d671df ]

IMA allocates kernel virtual memory to carry forward the measurement
list, from the current kernel to the next kernel on kexec system call,
in ima_add_kexec_buffer() function.  In error code paths this memory
is not freed resulting in memory leak.

Free the memory allocated for the IMA measurement list in
the error code paths in ima_add_kexec_buffer() function.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Fixes: 7b8589cc29e7 ("ima: on soft reboot, save the measurement list")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-12 12:52:21 +08:00
Dinghao Liu 98c246cd50 evm: Fix memleak in init_desc
[ Upstream commit ccf11dbaa07b328fa469415c362d33459c140a37 ]

tmp_tfm is allocated, but not freed on subsequent kmalloc failure, which
leads to a memory leak.  Free tmp_tfm.

Fixes: d46eb3699502b ("evm: crypto hash replaced by shash")
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
[zohar@linux.ibm.com: formatted/reworded patch description]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-12 12:52:18 +08:00
Roberto Sassu bbad2a93c3 ima: Don't modify file descriptor mode on the fly
commit 207cdd565dfc95a0a5185263a567817b7ebf5467 upstream.

Commit a408e4a86b36b ("ima: open a new file instance if no read
permissions") already introduced a second open to measure a file when the
original file descriptor does not allow it. However, it didn't remove the
existing method of changing the mode of the original file descriptor, which
is still necessary if the current process does not have enough privileges
to open a new one.

Changing the mode isn't really an option, as the filesystem might need to
do preliminary steps to make the read possible. Thus, this patch removes
the code and keeps the second open as the only option to measure a file
when it is unreadable with the original file descriptor.

Cc: <stable@vger.kernel.org> # 4.20.x: 0014cc04e8ec0 ima: Set file->f_mode
Fixes: 2fe5d6def1672 ("ima: integrity appraisal extension")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:43:35 +08:00
Maurizio Drocco d90a5d2101 ima: extend boot_aggregate with kernel measurements
[ Upstream commit 20c59ce010f84300f6c655d32db2610d3433f85c ]

Registers 8-9 are used to store measurements of the kernel and its
command line (e.g., grub2 bootloader with tpm module enabled). IMA
should include them in the boot aggregate. Registers 8-9 should be
only included in non-SHA1 digests to avoid ambiguity.

Signed-off-by: Maurizio Drocco <maurizio.drocco@ibm.com>
Reviewed-by: Bruno Meneguele <bmeneg@redhat.com>
Tested-by: Bruno Meneguele <bmeneg@redhat.com>  (TPM 1.2, TPM 2.0)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:41:53 +08:00
Roberto Sassu 13f9e1fe55 evm: Check size of security.evm before using it
commit 455b6c9112eff8d249e32ba165742085678a80a4 upstream.

This patch checks the size for the EVM_IMA_XATTR_DIGSIG and
EVM_XATTR_PORTABLE_DIGSIG types to ensure that the algorithm is read from
the buffer returned by vfs_getxattr_alloc().

Cc: stable@vger.kernel.org # 4.19.x
Fixes: 5feeb61183dde ("evm: Allow non-SHA1 digital signatures")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:39:34 +08:00
Roberto Sassu 200b416020 ima: Don't ignore errors from crypto_shash_update()
commit 60386b854008adc951c470067f90a2d85b5d520f upstream.

Errors returned by crypto_shash_update() are not checked in
ima_calc_boot_aggregate_tfm() and thus can be overwritten at the next
iteration of the loop. This patch adds a check after calling
crypto_shash_update() and returns immediately if the result is not zero.

Cc: stable@vger.kernel.org
Fixes: 3323eec921efd ("integrity: IMA as an integrity service provider")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:38:21 +08:00
Tyler Hicks 81908a8b3c ima: Have the LSM free its audit rule
[ Upstream commit 9ff8a616dfab96a4fa0ddd36190907dc68886d9b ]

Ask the LSM to free its audit rule rather than directly calling kfree().
Both AppArmor and SELinux do additional work in their audit_rule_free()
hooks. Fix memory leaks by allowing the LSMs to perform necessary work.

Fixes: b16942455193 ("ima: use the lsm policy update notifier")
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Janne Karhunen <janne.karhunen@gmail.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:33:35 +08:00
Bruno Meneguele 1023b78389 ima: move APPRAISE_BOOTPARAM dependency on ARCH_POLICY to runtime
commit 311aa6aafea446c2f954cc19d66425bfed8c4b0b upstream.

The IMA_APPRAISE_BOOTPARAM config allows enabling different "ima_appraise="
modes - log, fix, enforce - at run time, but not when IMA architecture
specific policies are enabled.  This prevents properly labeling the
filesystem on systems where secure boot is supported, but not enabled on the
platform.  Only when secure boot is actually enabled should these IMA
appraise modes be disabled.

This patch removes the compile time dependency and makes it a runtime
decision, based on the secure boot state of that platform.

Test results as follows:

-> x86-64 with secure boot enabled

[    0.015637] Kernel command line: <...> ima_policy=appraise_tcb ima_appraise=fix
[    0.015668] ima: Secure boot enabled: ignoring ima_appraise=fix boot parameter option

-> powerpc with secure boot disabled

[    0.000000] Kernel command line: <...> ima_policy=appraise_tcb ima_appraise=fix
[    0.000000] Secure boot mode disabled

-> Running the system without secure boot and with both options set:

CONFIG_IMA_APPRAISE_BOOTPARAM=y
CONFIG_IMA_ARCH_POLICY=y

Audit prompts "missing-hash" but still allow execution and, consequently,
filesystem labeling:

type=INTEGRITY_DATA msg=audit(07/09/2020 12:30:27.778:1691) : pid=4976
uid=root auid=root ses=2
subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 op=appraise_data
cause=missing-hash comm=bash name=/usr/bin/evmctl dev="dm-0" ino=493150
res=no

Cc: stable@vger.kernel.org
Fixes: d958083a8f64 ("x86/ima: define arch_get_ima_policy() for x86")
Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Cc: stable@vger.kernel.org # 5.0
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:33:11 +08:00
Krzysztof Struczynski e855a30791 ima: Set again build_ima_appraise variable
[ Upstream commit b59fda449cf07f2db3be3a67142e6c000f5e8d79 ]

After adding the new add_rule() function in commit c52657d93b05
("ima: refactor ima_init_policy()"), all appraisal flags are added to the
temp_ima_appraise variable. Revert to the previous behavior instead of
removing build_ima_appraise, to benefit from the protection offered by
__ro_after_init.

The mentioned commit introduced a bug, as it makes all the flags
modifiable, while build_ima_appraise flags can be protected with
__ro_after_init.

Cc: stable@vger.kernel.org # 5.0.x
Fixes: c52657d93b05 ("ima: refactor ima_init_policy()")
Co-developed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:29:44 +08:00
Krzysztof Struczynski b92c1c8d25 ima: Remove redundant policy rule set in add_rules()
[ Upstream commit 6ee28442a465ab4c4be45e3b15015af24b1ba906 ]

Function ima_appraise_flag() returns the flag to be set in
temp_ima_appraise depending on the hook identifier passed as an argument.
It is not necessary to set the flag again for the POLICY_CHECK hook.

Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:29:43 +08:00
Roberto Sassu 144d859b1a evm: Fix possible memory leak in evm_calc_hmac_or_hash()
commit 0c4395fb2aa77341269ea619c5419ea48171883f upstream.

Don't immediately return if the signature is portable and security.ima is
not present. Just set error so that memory allocated is freed before
returning from evm_calc_hmac_or_hash().

Fixes: 50b977481fce9 ("EVM: Add support for portable signature format")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:29:42 +08:00
Roberto Sassu 8e982a9952 ima: Remove __init annotation from ima_pcrread()
commit 8b8c704d913b0fe490af370631a4200e26334ec0 upstream.

Commit 6cc7c266e5b4 ("ima: Call ima_calc_boot_aggregate() in
ima_eventdigest_init()") added a call to ima_calc_boot_aggregate() so that
the digest can be recalculated for the boot_aggregate measurement entry if
the 'd' template field has been requested. For the 'd' field, only SHA1 and
MD5 digests are accepted.

Given that ima_eventdigest_init() does not have the __init annotation, all
functions called should not have it. This patch removes __init from
ima_pcrread().

Cc: stable@vger.kernel.org
Fixes:  6cc7c266e5b4 ("ima: Call ima_calc_boot_aggregate() in ima_eventdigest_init()")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:29:41 +08:00
Roberto Sassu 9050232318 ima: Call ima_calc_boot_aggregate() in ima_eventdigest_init()
commit 6cc7c266e5b47d3cd2b5bb7fd3aac4e6bb2dd1d2 upstream.

If the template field 'd' is chosen and the digest to be added to the
measurement entry was not calculated with SHA1 or MD5, it is
recalculated with SHA1, by using the passed file descriptor. However, this
cannot be done for boot_aggregate, because there is no file descriptor.

This patch adds a call to ima_calc_boot_aggregate() in
ima_eventdigest_init(), so that the digest can be recalculated also for the
boot_aggregate entry.

Cc: stable@vger.kernel.org # 3.13.x
Fixes: 3ce1217d6cd5d ("ima: define template fields library and new helpers")
Reported-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:29:41 +08:00
Roberto Sassu b426d271fb ima: Directly assign the ima_default_policy pointer to ima_rules
commit 067a436b1b0aafa593344fddd711a755a58afb3b upstream.

This patch prevents the following oops:

[   10.771813] BUG: kernel NULL pointer dereference, address: 0000000000000
[...]
[   10.779790] RIP: 0010:ima_match_policy+0xf7/0xb80
[...]
[   10.798576] Call Trace:
[   10.798993]  ? ima_lsm_policy_change+0x2b0/0x2b0
[   10.799753]  ? inode_init_owner+0x1a0/0x1a0
[   10.800484]  ? _raw_spin_lock+0x7a/0xd0
[   10.801592]  ima_must_appraise.part.0+0xb6/0xf0
[   10.802313]  ? ima_fix_xattr.isra.0+0xd0/0xd0
[   10.803167]  ima_must_appraise+0x4f/0x70
[   10.804004]  ima_post_path_mknod+0x2e/0x80
[   10.804800]  do_mknodat+0x396/0x3c0

It occurs when there is a failure during IMA initialization, and
ima_init_policy() is not called. IMA hooks still call ima_match_policy()
but ima_rules is NULL. This patch prevents the crash by directly assigning
the ima_default_policy pointer to ima_rules when ima_rules is defined. This
wouldn't alter the existing behavior, as ima_rules is always set at the end
of ima_init_policy().

Cc: stable@vger.kernel.org # 3.7.x
Fixes: 07f6a79415d7d ("ima: add appraise action keywords and default rules")
Reported-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:29:41 +08:00
Roberto Sassu 8da7a19280 ima: Evaluate error in init_ima()
commit e144d6b265415ddbdc54b3f17f4f95133effa5a8 upstream.

Evaluate error in init_ima() before register_blocking_lsm_notifier() and
return if not zero.

Cc: stable@vger.kernel.org # 5.3.x
Fixes: b16942455193 ("ima: use the lsm policy update notifier")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:29:41 +08:00
Roberto Sassu 7372d0d72b ima: Switch to ima_hash_algo for boot aggregate
commit 6f1a1d103b48b1533a9c804e7a069e2c8e937ce7 upstream.

boot_aggregate is the first entry of IMA measurement list. Its purpose is
to link pre-boot measurements to IMA measurements. As IMA was designed to
work with a TPM 1.2, the SHA1 PCR bank was always selected even if a
TPM 2.0 with support for stronger hash algorithms is available.

This patch first tries to find a PCR bank with the IMA default hash
algorithm. If it does not find it, it selects the SHA256 PCR bank for
TPM 2.0 and SHA1 for TPM 1.2. Ultimately, it selects SHA1 also for TPM 2.0
if the SHA256 PCR bank is not found.

If none of the PCR banks above can be found, boot_aggregate file digest is
filled with zeros, as for TPM bypass, making it impossible to perform a
remote attestation of the system.

Cc: stable@vger.kernel.org # 5.1.x
Fixes: 879b589210a9 ("tpm: retrieve digest size of unknown algorithms with PCR read")
Reported-by: Jerry Snitselaar <jsnitsel@redhat.com>
Suggested-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:29:41 +08:00
Krzysztof Struczynski c96141ee38 ima: Fix ima digest hash table key calculation
commit 1129d31b55d509f15e72dc68e4b5c3a4d7b4da8d upstream.

Function hash_long() accepts unsigned long, while currently only one byte
is passed from ima_hash_key(), which calculates a key for ima_htable.

Given that hashing the digest does not give clear benefits compared to
using the digest itself, remove hash_long() and return the modulus
calculated on the first two bytes of the digest with the number of slots.
Also reduce the depth of the hash table by doubling the number of slots.

Cc: stable@vger.kernel.org
Fixes: 3323eec921ef ("integrity: IMA as an integrity service provider")
Co-developed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Acked-by: David.Laight@aculab.com (big endian system concerns)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-16 16:29:41 +08:00
Madhuparna Bhowmik 80dd1bfaba evm: Fix RCU list related warnings
[ Upstream commit 770f60586d2af0590be263f55fd079226313922c ]

This patch fixes the following warning and few other instances of
traversal of evm_config_xattrnames list:

[   32.848432] =============================
[   32.848707] WARNING: suspicious RCU usage
[   32.848966] 5.7.0-rc1-00006-ga8d5875ce5f0b #1 Not tainted
[   32.849308] -----------------------------
[   32.849567] security/integrity/evm/evm_main.c:231 RCU-list traversed in non-reader section!!

Since entries are only added to the list and never deleted, use
list_for_each_entry_lockless() instead of list_for_each_entry_rcu for
traversing the list.  Also, add a relevant comment in evm_secfs.c to
indicate this fact.

Reported-by: kernel test robot <lkp@intel.com>
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org> (RCU viewpoint)
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:28:47 +08:00
Dan Carpenter acb30a14d4 evm: Fix a small race in init_desc()
[ Upstream commit 8433856947217ebb5697a8ff9c4c9cad4639a2cf ]

The IS_ERR_OR_NULL() function has two conditions and if we got really
unlucky we could hit a race where "ptr" started as an error pointer and
then was set to NULL.  Both conditions would be false even though the
pointer at the end was NULL.

This patch fixes the problem by ensuring that "*tfm" can only be NULL
or valid.  I have introduced a "tmp_tfm" variable to make that work.  I
also reversed a condition and pulled the code in one tab.

Reported-by: Roberto Sassu <roberto.sassu@huawei.com>
Fixes: 53de3b080d5e ("evm: Check also if *tfm is an error pointer in init_desc()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Roberto Sassu <roberto.sassu@huawei.com>
Acked-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:28:07 +08:00
Roberto Sassu c382d9fa06 ima: Fix return value of ima_write_policy()
[ Upstream commit 2e3a34e9f409ebe83d1af7cd2f49fca7af97dfac ]

This patch fixes the return value of ima_write_policy() when a new policy
is directly passed to IMA and the current policy requires appraisal of the
file containing the policy. Currently, if appraisal is not in ENFORCE mode,
ima_write_policy() returns 0 and leads user space applications to an
endless loop. Fix this issue by denying the operation regardless of the
appraisal mode.

Cc: stable@vger.kernel.org # 4.10.x
Fixes: 19f8a84713edc ("ima: measure and appraise the IMA policy itself")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:28:06 +08:00
Roberto Sassu 90e944aa9a evm: Check also if *tfm is an error pointer in init_desc()
[ Upstream commit 53de3b080d5eae31d0de219617155dcc34e7d698 ]

This patch avoids a kernel panic due to accessing an error pointer set by
crypto_alloc_shash(). It occurs especially when there are many files that
require an unsupported algorithm, as it would increase the likelihood of
the following race condition:

Task A: *tfm = crypto_alloc_shash() <= error pointer
Task B: if (*tfm == NULL) <= *tfm is not NULL, use it
Task B: rc = crypto_shash_init(desc) <= panic
Task A: *tfm = NULL

This patch uses the IS_ERR_OR_NULL macro to determine whether or not a new
crypto context must be created.

Cc: stable@vger.kernel.org
Fixes: d46eb3699502b ("evm: crypto hash replaced by shash")
Co-developed-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:28:06 +08:00
Roberto Sassu c73215b82c ima: Set file->f_mode instead of file->f_flags in ima_calc_file_hash()
[ Upstream commit 0014cc04e8ec077dc482f00c87dfd949cfe2b98f ]

Commit a408e4a86b36 ("ima: open a new file instance if no read
permissions") tries to create a new file descriptor to calculate a file
digest if the file has not been opened with O_RDONLY flag. However, if a
new file descriptor cannot be obtained, it sets the FMODE_READ flag to
file->f_flags instead of file->f_mode.

This patch fixes this issue by replacing f_flags with f_mode as it was
before that commit.

Cc: stable@vger.kernel.org # 4.20.x
Fixes: a408e4a86b36 ("ima: open a new file instance if no read permissions")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-16 16:28:06 +08:00
Kaixu Xia 590eaf1fec Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
2021-03-16 11:01:34 +08:00