commit 6e9722e9a7 upstream.
'name_size' does not have any range checks, and it just directly indexes
with TPM_ALG_ID, which could lead into memory corruption at worst.
Address the issue by only processing known values and returning -EINVAL for
unrecognized values.
Make also 'tpm_buf_append_name' and 'tpm_buf_fill_hmac_session' fallible so
that errors are detected before causing any spurious TPM traffic.
End also the authorization session on failure in both of the functions, as
the session state would be then by definition corrupted.
Cc: stable@vger.kernel.org # v6.10+
Fixes: 1085b8276b ("tpm: Add the rest of the session HMAC API")
Reviewed-by: Jonathan McDowell <noodles@meta.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 62cd5d480b upstream.
'tpm2_load_cmd' allocates a tempoary blob indirectly via 'tpm2_key_decode'
but it is not freed in the failure paths. Address this by wrapping the blob
into with a cleanup helper.
Cc: stable@vger.kernel.org # v5.13+
Fixes: f221974525 ("security: keys: trusted: use ASN.1 TPM2 key format for the blobs")
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 738c9738e6 ]
In ima_match_rules(), if ima_filter_rule_match() returns -ENOENT due to
the rule being NULL, the function incorrectly skips the 'if (!rc)' check
and sets 'result = true'. The LSM rule is considered a match, causing
extra files to be measured by IMA.
This issue can be reproduced in the following scenario:
After unloading the SELinux policy module via 'semodule -d', if an IMA
measurement is triggered before ima_lsm_rules is updated,
in ima_match_rules(), the first call to ima_filter_rule_match() returns
-ESTALE. This causes the code to enter the 'if (rc == -ESTALE &&
!rule_reinitialized)' block, perform ima_lsm_copy_rule() and retry. In
ima_lsm_copy_rule(), since the SELinux module has been removed, the rule
becomes NULL, and the second call to ima_filter_rule_match() returns
-ENOENT. This bypasses the 'if (!rc)' check and results in a false match.
Call trace:
selinux_audit_rule_match+0x310/0x3b8
security_audit_rule_match+0x60/0xa0
ima_match_rules+0x2e4/0x4a0
ima_match_policy+0x9c/0x1e8
ima_get_action+0x48/0x60
process_measurement+0xf8/0xa98
ima_bprm_check+0x98/0xd8
security_bprm_check+0x5c/0x78
search_binary_handler+0x6c/0x318
exec_binprm+0x58/0x1b8
bprm_execve+0xb8/0x130
do_execveat_common.isra.0+0x1a8/0x258
__arm64_sys_execve+0x48/0x68
invoke_syscall+0x50/0x128
el0_svc_common.constprop.0+0xc8/0xf0
do_el0_svc+0x24/0x38
el0_svc+0x44/0x200
el0t_64_sync_handler+0x100/0x130
el0t_64_sync+0x3c8/0x3d0
Fix this by changing 'if (!rc)' to 'if (rc <= 0)' to ensure that error
codes like -ENOENT do not bypass the check and accidentally result in a
successful match.
Fixes: 4af4662fa4 ("integrity: IMA policy")
Signed-off-by: Zhao Yipeng <zhaoyipeng5@huawei.com>
Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 674e2b2479 ]
This command:
# echo foo/bar >/proc/$$/attr/smack/current
gives the task a label 'foo' w/o indication
that label does not match input.
Setting the label with lsm_set_self_attr() syscall
behaves identically.
This occures because:
1) smk_parse_smack() is used to convert input to a label
2) smk_parse_smack() takes only that part from the
beginning of the input that looks like a label.
3) `/' is prohibited in labels, so only "foo" is taken.
(2) is by design, because smk_parse_smack() is used
for parsing strings which are more than just a label.
Silent failure is not a good thing, and there are two
indicators that this was not done intentionally:
(size >= SMK_LONGLABEL) ~> invalid
clause at the beginning of the do_setattr() and the
"Returns the length of the smack label" claim
in the do_setattr() description.
So I fixed this by adding one tiny check:
the taken label length == input length.
Since input length is now strictly controlled,
I changed the two ways of setting label
smack_setselfattr(): lsm_set_self_attr() syscall
smack_setprocattr(): > /proc/.../current
to accommodate the divergence in
what they understand by "input length":
smack_setselfattr counts mandatory \0 into input length,
smack_setprocattr does not.
smack_setprocattr allows various trailers after label
Related changes:
* fixed description for smk_parse_smack
* allow unprivileged tasks validate label syntax.
* extract smk_parse_label_len() from smk_parse_smack()
so parsing may be done w/o string allocation.
* extract smk_import_valid_label() from smk_import_entry()
to avoid repeated parsing.
* smk_parse_smack(): scan null-terminated strings
for no more than SMK_LONGLABEL(256) characters
* smack_setselfattr(): require struct lsm_ctx . flags == 0
to reserve them for future.
Fixes: e114e47377 ("Smack: Simplified Mandatory Access Control Kernel")
Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c147e13ea7 ]
If an unprivileged task is allowed to relabel itself
(/smack/relabel-self is not empty),
it can freely create new labels by writing their
names into own /proc/PID/attr/smack/current
This occurs because do_setattr() imports
the provided label in advance,
before checking "relabel-self" list.
This change ensures that the "relabel-self" list
is checked before importing the label.
Fixes: 38416e5393 ("Smack: limited capability for changing process label")
Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 78fc6a94be ]
According to [1], the label of a UNIX domain socket (UDS)
file (i.e., the filesystem object representing the socket)
is not supposed to participate in Smack security.
To achieve this, [1] labels UDS files with "*"
in smack_d_instantiate().
Before [2], smack_d_instantiate() was responsible
for initializing Smack security for all inodes,
except ones under /proc
[2] imposed the sole responsibility for initializing
inode security for newly created filesystem objects
on smack_inode_init_security().
However, smack_inode_init_security() lacks some logic
present in smack_d_instantiate().
In particular, it does not label UDS files with "*".
This patch adds the missing labeling of UDS files
with "*" to smack_inode_init_security().
Labeling UDS files with "*" in smack_d_instantiate()
still works for stale UDS files that already exist on
disk. Stale UDS files are useless, but I keep labeling
them for consistency and maybe to make easier for user
to delete them.
Compared to [1], this version introduces the following
improvements:
* UDS file label is held inside inode only
and not saved to xattrs.
* relabeling UDS files (setxattr, removexattr, etc.)
is blocked.
[1] 2010-11-24 Casey Schaufler
commit b4e0d5f079 ("Smack: UDS revision")
[2] 2023-11-16 roberto.sassu
Fixes: e63d86b8b7 ("smack: Initialize the in-memory inode in smack_inode_init_security()")
Link: https://lore.kernel.org/linux-security-module/20231116090125.187209-5-roberto.sassu@huaweicloud.com/
Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 69204f6cdb ]
If memory allocation for the SMACK64TRANSMUTE
xattr value fails in smack_inode_init_security(),
the SMK_INODE_INSTANT flag is not set in
(struct inode_smack *issp)->smk_flags,
leaving the inode as not "instantiated".
It does not matter if fs frees the inode
after failed smack_inode_init_security() call,
but there is no guarantee for this.
To be safe, mark the inode as "instantiated",
even if allocation of xattr values fails.
Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Stable-dep-of: 78fc6a94be ("smack: fix bug: invalid label of unix socket file")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 195da3ff24 ]
When a new file system object is created
and the conditions for label transmutation are met,
the SMACK64TRANSMUTE extended attribute is set
on the object regardless of its type:
file, pipe, socket, symlink, or directory.
However,
SMACK64TRANSMUTE may only be set on directories.
This bug is a combined effect of the commits [1] and [2]
which both transfer functionality
from smack_d_instantiate() to smack_inode_init_security(),
but only in part.
Commit [1] set blank SMACK64TRANSMUTE on improper object types.
Commit [2] set "TRUE" SMACK64TRANSMUTE on improper object types.
[1] 2023-06-10,
Fixes: baed456a6a ("smack: Set the SMACK64TRANSMUTE xattr in smack_inode_init_security()")
Link: https://lore.kernel.org/linux-security-module/20230610075738.3273764-3-roberto.sassu@huaweicloud.com/
[2] 2023-11-16,
Fixes: e63d86b8b7 ("smack: Initialize the in-memory inode in smack_inode_init_security()")
Link: https://lore.kernel.org/linux-security-module/20231116090125.187209-5-roberto.sassu@huaweicloud.com/
Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Stable-dep-of: 78fc6a94be ("smack: fix bug: invalid label of unix socket file")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 88b4cbcf6b ]
Currently when both IMA and EVM are in fix mode, the IMA signature will
be reset to IMA hash if a program first stores IMA signature in
security.ima and then writes/removes some other security xattr for the
file.
For example, on Fedora, after booting the kernel with "ima_appraise=fix
evm=fix ima_policy=appraise_tcb" and installing rpm-plugin-ima,
installing/reinstalling a package will not make good reference IMA
signature generated. Instead IMA hash is generated,
# getfattr -m - -d -e hex /usr/bin/bash
# file: usr/bin/bash
security.ima=0x0404...
This happens because when setting security.selinux, the IMA_DIGSIG flag
that had been set early was cleared. As a result, IMA hash is generated
when the file is closed.
Similarly, IMA signature can be cleared on file close after removing
security xattr like security.evm or setting/removing ACL.
Prevent replacing the IMA file signature with a file hash, by preventing
the IMA_DIGSIG flag from being reset.
Here's a minimal C reproducer which sets security.selinux as the last
step which can also replaced by removing security.evm or setting ACL,
#include <stdio.h>
#include <sys/xattr.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
int main() {
const char* file_path = "/usr/sbin/test_binary";
const char* hex_string = "030204d33204490066306402304";
int length = strlen(hex_string);
char* ima_attr_value;
int fd;
fd = open(file_path, O_WRONLY|O_CREAT|O_EXCL, 0644);
if (fd == -1) {
perror("Error opening file");
return 1;
}
ima_attr_value = (char*)malloc(length / 2 );
for (int i = 0, j = 0; i < length; i += 2, j++) {
sscanf(hex_string + i, "%2hhx", &ima_attr_value[j]);
}
if (fsetxattr(fd, "security.ima", ima_attr_value, length/2, 0) == -1) {
perror("Error setting extended attribute");
close(fd);
return 1;
}
const char* selinux_value= "system_u:object_r:bin_t:s0";
if (fsetxattr(fd, "security.selinux", selinux_value, strlen(selinux_value), 0) == -1) {
perror("Error setting extended attribute");
close(fd);
return 1;
}
close(fd);
return 0;
}
Signed-off-by: Coiby Xu <coxu@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit eed0e3d305 upstream.
To prevent timing attacks, HMAC value comparison needs to be constant
time. Replace the memcmp() with the correct function, crypto_memneq().
[For the Fixes commit I used the commit that introduced the memcmp().
It predates the introduction of crypto_memneq(), but it was still a bug
at the time even though a helper function didn't exist yet.]
Fixes: d00a1c72f7 ("keys: add new trusted key-type")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 54d94c422f ]
When CONFIG_SECURITY is not set, CONFIG_LSM (builtin_lsm_order) does
not need to be visible and settable since builtin_lsm_order is defined in
security.o, which is only built when CONFIG_SECURITY=y.
So make CONFIG_LSM depend on CONFIG_SECURITY.
Fixes: 13e735c0e9 ("LSM: Introduce CONFIG_LSM")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
[PM: subj tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit c567de2c4f upstream.
The dfa blob stream for the aa_dfa_unpack() function is expected to be aligned
on a 8 byte boundary.
The static nulldfa_src[] and stacksplitdfa_src[] arrays store the initial
apparmor dfa blob streams, but since they are declared as an array-of-chars
the compiler and linker will only ensure a "char" (1-byte) alignment.
Add an __aligned(8) annotation to the arrays to tell the linker to always
align them on a 8-byte boundary. This avoids runtime warnings at startup on
alignment-sensitive platforms like parisc such as:
Kernel: unaligned access to 0x7f2a584a in aa_dfa_unpack+0x124/0x788 (iir 0xca0109f)
Kernel: unaligned access to 0x7f2a584e in aa_dfa_unpack+0x210/0x788 (iir 0xca8109c)
Kernel: unaligned access to 0x7f2a586a in aa_dfa_unpack+0x278/0x788 (iir 0xcb01090)
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Fixes: 98b824ff89 ("apparmor: refcount the pdb")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a9eb185be8 ]
x_table_lookup currently does stacking during label_parse() if the
target specifies a stack but its only caller ensures that it will
never be used with stacking.
Refactor to slightly simplify the code in x_to_label(), this
also fixes a long standing problem where x_to_labels check on stacking
is only on the first element to the table option list, instead of
the element that is found and used.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c5bf96d20f ]
When using AppArmor profiles inside an unprivileged container,
the link operation observes an unshifted ouid.
(tested with LXD and Incus)
For example, root inside container and uid 1000000 outside, with
`owner /root/link l,` profile entry for ln:
/root$ touch chain && ln chain link
==> dmesg
apparmor="DENIED" operation="link" class="file"
namespace="root//lxd-feet_<var-snap-lxd-common-lxd>" profile="linkit"
name="/root/link" pid=1655 comm="ln" requested_mask="l" denied_mask="l"
fsuid=1000000 ouid=0 [<== should be 1000000] target="/root/chain"
Fix by mapping inode uid of old_dentry in aa_path_link() rather than
using it directly, similarly to how it's mapped in __file_path_perm()
later in the file.
Signed-off-by: Gabriel Totev <gabriel.totev@zetier.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 27cd1bf124 ]
incidentally, securityfs_recursive_remove() is broken without that -
it leaks dentries, since simple_recursive_removal() does not expect
anything of that sort. It could be worked around by dput() in
remove_one() callback, but it's easier to just drop that double-get
stuff.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c68804199d ]
The testcase triggers some unnecessary unaligned memory accesses on the
parisc architecture:
Kernel: unaligned access to 0x12f28e27 in policy_unpack_test_init+0x180/0x374 (iir 0x0cdc1280)
Kernel: unaligned access to 0x12f28e67 in policy_unpack_test_init+0x270/0x374 (iir 0x64dc00ce)
Use the existing helper functions put_unaligned_le32() and
put_unaligned_le16() to avoid such warnings on architectures which
prefer aligned memory accesses.
Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: 98c0cc48e2 ("apparmor: fix policy_unpack_test on big endian systems")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a88db916b8 ]
Conflicting attachment resolution is based on the number of states
traversed to reach an accepting state in the attachment DFA, accounting
for DFA loops traversed during the matching process. However, the loop
counting logic had multiple bugs:
- The inc_wb_pos macro increments both position and length, but length
is supposed to saturate upon hitting buffer capacity, instead of
wrapping around.
- If no revisited state is found when traversing the history, is_loop
would still return true, as if there was a loop found the length of
the history buffer, instead of returning false and signalling that
no loop was found. As a result, the adjustment step of
aa_dfa_leftmatch would sometimes produce negative counts with loop-
free DFAs that traversed enough states.
- The iteration in the is_loop for loop is supposed to stop before
i = wb->len, so the conditional should be < instead of <=.
This patch fixes the above bugs as well as the following nits:
- The count and size fields in struct match_workbuf were not used,
so they can be removed.
- The history buffer in match_workbuf semantically stores aa_state_t
and not unsigned ints, even if aa_state_t is currently unsigned int.
- The local variables in is_loop are counters, and thus should be
unsigned ints instead of aa_state_t's.
Fixes: 21f6066105 ("apparmor: improve overlapping domain attachment resolution")
Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
Co-developed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6c055e6256 ]
WB_HISTORY_SIZE was defined to be a value not a power of 2, despite a
comment in the declaration of struct match_workbuf stating it is and a
modular arithmetic usage in the inc_wb_pos macro assuming that it is. Bump
WB_HISTORY_SIZE's value up to 32 and add a BUILD_BUG_ON_NOT_POWER_OF_2
line to ensure that any future changes to the value of WB_HISTORY_SIZE
respect this requirement.
Fixes: 136db99485 ("apparmor: increase left match history buffer size")
Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fde46f60f6 ]
If the end result of a security_compute_sid() computation matches the
ssid or tsid, return that SID rather than looking it up again. This
avoids the problem of multiple initial SIDs that map to the same
context.
Cc: stable@vger.kernel.org
Reported-by: Guido Trentalancia <guido@trentalancia.com>
Fixes: ae254858ce ("selinux: introduce an initial SID for early boot processes")
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Tested-by: Guido Trentalancia <guido@trentalancia.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c7fb50cecf ]
This reverts commit ccfd889acb
The indicated commit
* does not describe the problem that change tries to solve
* has programming issues
* introduces a bug: forever clears NETLBL_SECATTR_MLS_CAT
in (struct smack_known *)skp->smk_netlabel.flags
Reverting the commit to reapproach original problem
Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a158a937d8 ]
If SMACK label has CIPSO representation w/o categories, e.g.:
| # cat /smack/cipso2
| foo 10
| @ 250/2
| ...
then SMACK does not recognize such CIPSO in input ipv4 packets
and substitues '*' label instead. Audit records may look like
| lsm=SMACK fn=smack_socket_sock_rcv_skb action=denied
| subject="*" object="_" requested=w pid=0 comm="swapper/1" ...
This happens in two steps:
1) security/smack/smackfs.c`smk_set_cipso
does not clear NETLBL_SECATTR_MLS_CAT
from (struct smack_known *)skp->smk_netlabel.flags
on assigning CIPSO w/o categories:
| rcu_assign_pointer(skp->smk_netlabel.attr.mls.cat, ncats.attr.mls.cat);
| skp->smk_netlabel.attr.mls.lvl = ncats.attr.mls.lvl;
2) security/smack/smack_lsm.c`smack_from_secattr
can not match skp->smk_netlabel with input packet's
struct netlbl_lsm_secattr *sap
because sap->flags have not NETLBL_SECATTR_MLS_CAT (what is correct)
but skp->smk_netlabel.flags have (what is incorrect):
| if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) {
| if ((skp->smk_netlabel.flags &
| NETLBL_SECATTR_MLS_CAT) == 0)
| found = 1;
| break;
| }
This commit sets/clears NETLBL_SECATTR_MLS_CAT in
skp->smk_netlabel.flags according to the presense of CIPSO categories.
The update of smk_netlabel is not atomic, so input packets processing
still may be incorrect during short time while update proceeds.
Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 30d68cb0c3 ]
On IMA policy update, if a measure rule exists in the policy,
IMA_MEASURE is set for ima_policy_flags which makes the violation_check
variable always true. Coupled with a no-action on MAY_READ for a
FILE_CHECK call, we're always taking the inode_lock().
This becomes a performance problem for extremely heavy read-only workloads.
Therefore, prevent this only in the case there's no action to be taken.
Signed-off-by: Frederick Lawler <fred@cloudflare.com>
Acked-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 18eb75f3af upstream.
Because Linux credentials are managed per thread, user space relies on
some hack to synchronize credential update across threads from the same
process. This is required by the Native POSIX Threads Library and
implemented by set*id(2) wrappers and libcap(3) to use tgkill(2) to
synchronize threads. See nptl(7) and libpsx(3). Furthermore, some
runtimes like Go do not enable developers to have control over threads
[1].
To avoid potential issues, and because threads are not security
boundaries, let's relax the Landlock (optional) signal scoping to always
allow signals sent between threads of the same process. This exception
is similar to the __ptrace_may_access() one.
hook_file_set_fowner() now checks if the target task is part of the same
process as the caller. If this is the case, then the related signal
triggered by the socket will always be allowed.
Scoping of abstract UNIX sockets is not changed because kernel objects
(e.g. sockets) should be tied to their creator's domain at creation
time.
Note that creating one Landlock domain per thread puts each of these
threads (and their future children) in their own scope, which is
probably not what users expect, especially in Go where we do not control
threads. However, being able to drop permissions on all threads should
not be restricted by signal scoping. We are working on a way to make it
possible to atomically restrict all threads of a process with the same
domain [2].
Add erratum for signal scoping.
Closes: https://github.com/landlock-lsm/go-landlock/issues/36
Fixes: 54a6e6bbf3 ("landlock: Add signal scoping")
Fixes: c899496501 ("selftests/landlock: Test signal scoping for threads")
Depends-on: 26f204380a ("fs: Fix file_set_fowner LSM hook inconsistencies")
Link: https://pkg.go.dev/kernel.org/pub/linux/libs/security/libcap/psx [1]
Link: https://github.com/landlock-lsm/linux/issues/2 [2]
Cc: Günther Noack <gnoack@google.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Tahera Fahimi <fahimitahera@gmail.com>
Cc: stable@vger.kernel.org
Acked-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20250318161443.279194-6-mic@digikod.net
[mic: Add extra pointer check and RCU guard, and ease backport]
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 15383a0d63 upstream.
Some fixes may require user space to check if they are applied on the
running kernel before using a specific feature. For instance, this
applies when a restriction was previously too restrictive and is now
getting relaxed (e.g. for compatibility reasons). However, non-visible
changes for legitimate use (e.g. security fixes) do not require an
erratum.
Because fixes are backported down to a specific Landlock ABI, we need a
way to avoid cherry-pick conflicts. The solution is to only update a
file related to the lower ABI impacted by this issue. All the ABI files
are then used to create a bitmask of fixes.
The new errata interface is similar to the one used to get the supported
Landlock ABI version, but it returns a bitmask instead because the order
of fixes may not match the order of versions, and not all fixes may
apply to all versions.
The actual errata will come with dedicated commits. The description is
not actually used in the code but serves as documentation.
Create the landlock_abi_version symbol and use its value to check errata
consistency.
Update test_base's create_ruleset_checks_ordering tests and add errata
tests.
This commit is backportable down to the first version of Landlock.
Fixes: 3532b0b435 ("landlock: Enable user space to infer supported features")
Cc: Günther Noack <gnoack@google.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250318161443.279194-3-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a414016218 upstream.
Each time a file in policy, that is already opened for read, is opened
for write, a Time-of-Measure-Time-of-Use (ToMToU) integrity violation
audit message is emitted and a violation record is added to the IMA
measurement list. This occurs even if a ToMToU violation has already
been recorded.
Limit the number of ToMToU integrity violations per file open for read.
Note: The IMA_MAY_EMIT_TOMTOU atomic flag must be set from the reader
side based on policy. This may result in a per file open for read
ToMToU violation.
Since IMA_MUST_MEASURE is only used for violations, rename the atomic
IMA_MUST_MEASURE flag to IMA_MAY_EMIT_TOMTOU.
Cc: stable@vger.kernel.org # applies cleanly up to linux-6.6
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Tested-by: Petr Vorel <pvorel@suse.cz>
Reviewed-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>
commit 5b3cd80115 upstream.
Each time a file in policy, that is already opened for write, is opened
for read, an open-writers integrity violation audit message is emitted
and a violation record is added to the IMA measurement list. This
occurs even if an open-writers violation has already been recorded.
Limit the number of open-writers integrity violations for an existing
file open for write to one. After the existing file open for write
closes (__fput), subsequent open-writers integrity violations may be
emitted.
Cc: stable@vger.kernel.org # applies cleanly up to linux-6.6
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Tested-by: Petr Vorel <pvorel@suse.cz>
Reviewed-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>
[ Upstream commit 6cce0cc386 ]
Since inception [1], SMACK initializes ipv* child socket security
for connection-oriented communications (tcp/sctp/dccp)
during accept() syscall, in the security_sock_graft() hook:
| void smack_sock_graft(struct sock *sk, ...)
| {
| // only ipv4 and ipv6 are eligible here
| // ...
| ssp = sk->sk_security; // socket security
| ssp->smk_in = skp; // process label: smk_of_current()
| ssp->smk_out = skp; // process label: smk_of_current()
| }
This approach is incorrect for two reasons:
A) initialization occurs too late for child socket security:
The child socket is created by the kernel once the handshake
completes (e.g., for tcp: after receiving ack for syn+ack).
Data can legitimately start arriving to the child socket
immediately, long before the application calls accept()
on the socket.
Those data are (currently — were) processed by SMACK using
incorrect child socket security attributes.
B) Incoming connection requests are handled using the listening
socket's security, hence, the child socket must inherit the
listening socket's security attributes.
smack_sock_graft() initilizes the child socket's security with
a process label, as is done for a new socket()
But ... the process label is not necessarily the same as the
listening socket label. A privileged application may legitimately
set other in/out labels for a listening socket.
When this happens, SMACK processes incoming packets using
incorrect socket security attributes.
In [2] Michael Lontke noticed (A) and fixed it in [3] by adding
socket initialization into security_sk_clone_security() hook like
| void smack_sk_clone_security(struct sock *oldsk, struct sock *newsk)
| {
| *(struct socket_smack *)newsk->sk_security =
| *(struct socket_smack *)oldsk->sk_security;
| }
This initializes the child socket security with the parent (listening)
socket security at the appropriate time.
I was forced to revisit this old story because
smack_sock_graft() was left in place by [3] and continues overwriting
the child socket's labels with the process label,
and there might be a reason for this, so I undertook a study.
If the process label differs from the listening socket's labels,
the following occurs for ipv4:
assigning the smk_out is not accompanied by netlbl_sock_setattr,
so the outgoing packet's cipso label does not change.
So, the only effect of this assignment for interhost communications
is a divergence between the program-visible “out” socket label and
the cipso network label. For intrahost communications this label,
however, becomes visible via secmark netfilter marking, and is
checked for access rights by the client, receiving side.
Assigning the smk_in affects both interhost and intrahost
communications: the server begins to check access rights against
an wrong label.
Access check against wrong label (smk_in or smk_out),
unsurprisingly fails, breaking the connection.
The above affects protocols that calls security_sock_graft()
during accept(), namely: {tcp,dccp,sctp}/{ipv4,ipv6}
One extra security_sock_graft() caller, crypto/af_alg.c`af_alg_accept
is not affected, because smack_sock_graft() does nothing for PF_ALG.
To reproduce, assign non-default in/out labels to a listening socket,
setup rules between these labels and client label, attempt to connect
and send some data.
Ipv6 specific: ipv6 packets do not convey SMACK labels. To reproduce
the issue in interhost communications set opposite labels in
/smack/ipv6host on both hosts.
Ipv6 intrahost communications do not require tricking, because SMACK
labels are conveyed via secmark netfilter marking.
So, currently smack_sock_graft() is not useful, but harmful,
therefore, I have removed it.
This fixes the issue for {tcp,dccp}/{ipv4,ipv6},
but not sctp/{ipv4,ipv6}.
Although this change is necessary for sctp+smack to function
correctly, it is not sufficient because:
sctp/ipv4 does not call security_sk_clone() and
sctp/ipv6 ignores SMACK completely.
These are separate issues, belong to other subsystem,
and should be addressed separately.
[1] 2008-02-04,
Fixes: e114e47377 ("Smack: Simplified Mandatory Access Control Kernel")
[2] Michael Lontke, 2022-08-31, SMACK LSM checks wrong object label
during ingress network traffic
Link: https://lore.kernel.org/linux-security-module/6324997ce4fc092c5020a4add075257f9c5f6442.camel@elektrobit.com/
[3] 2022-08-31, michael.lontke,
commit 4ca165fc6c ("SMACK: Add sk_clone_security LSM hook")
Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bfcf4004bc ]
I want to be sure that ipv6-specific code
is not compiled in kernel binaries
if ipv6 is not configured.
[1] was getting rid of "unused variable" warning, but,
with that, it also mandated compilation of a handful ipv6-
specific functions in ipv4-only kernel configurations:
smk_ipv6_localhost, smack_ipv6host_label, smk_ipv6_check.
Their compiled bodies are likely to be removed by compiler
from the resulting binary, but, to be on the safe side,
I remove them from the compiler view.
[1]
Fixes: 00720f0e7f ("smack: avoid unused 'sip' variable warning")
Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 75845c6c1a upstream.
Once a key's reference count has been reduced to 0, the garbage collector
thread may destroy it at any time and so key_put() is not allowed to touch
the key after that point. The most key_put() is normally allowed to do is
to touch key_gc_work as that's a static global variable.
However, in an effort to speed up the reclamation of quota, this is now
done in key_put() once the key's usage is reduced to 0 - but now the code
is looking at the key after the deadline, which is forbidden.
Fix this by using a flag to indicate that a key can be gc'd now rather than
looking at the key's refcount in the garbage collector.
Fixes: 9578e327b2 ("keys: update key quotas in key_put()")
Reported-by: syzbot+6105ffc1ded71d194d6d@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/673b6aec.050a0220.87769.004a.GAE@google.com/
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: syzbot+6105ffc1ded71d194d6d@syzkaller.appspotmail.com
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 57a0ef02fe upstream.
Commit 0d73a55208 ("ima: re-introduce own integrity cache lock")
mistakenly reverted the performance improvement introduced in commit
42a4c60319 ("ima: fix ima_inode_post_setattr"). The unused bit mask was
subsequently removed by commit 11c60f23ed ("integrity: Remove unused
macro IMA_ACTION_RULE_FLAGS").
Restore the performance improvement by introducing the new mask
IMA_NONACTION_RULE_FLAGS, equal to IMA_NONACTION_FLAGS without
IMA_NEW_FILE, which is not a rule-specific flag.
Finally, reset IMA_NONACTION_RULE_FLAGS instead of IMA_NONACTION_FLAGS in
process_measurement(), if the IMA_CHANGE_ATTR atomic flag is set (after
file metadata modification).
With this patch, new files for which metadata were modified while they are
still open, can be reopened before the last file close (when security.ima
is written), since the IMA_NEW_FILE flag is not cleared anymore. Otherwise,
appraisal fails because security.ima is missing (files with IMA_NEW_FILE
set are an exception).
Cc: stable@vger.kernel.org # v4.16.x
Fixes: 0d73a55208 ("ima: re-introduce own integrity cache lock")
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>
commit e8d9fab39d upstream.
With vmalloc stack addresses enabled (CONFIG_VMAP_STACK=y) DCP trusted
keys can crash during en- and decryption of the blob encryption key via
the DCP crypto driver. This is caused by improperly using sg_init_one()
with vmalloc'd stack buffers (plain_key_blob).
Fix this by always using kmalloc() for buffers we give to the DCP crypto
driver.
Cc: stable@vger.kernel.org # v6.10+
Fixes: 0e28bf61a5 ("KEYS: trusted: dcp: fix leak of blob encryption key")
Signed-off-by: David Gstir <david@sigma-star.at>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 17d0d04f3c upstream.
attach->xmatch was not set when allocating a null profile, which is used in
complain mode to allocate a learning profile. This was causing downstream
failures in find_attach, which expected a valid xmatch but did not find
one under a certain sequence of profile transitions in complain mode.
This patch ensures the xmatch is set up properly for null profiles.
Signed-off-by: Ryan Lee <ryan.lee@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Cc: Paul Kramme <kramme@digitalmanufaktur.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 900f83cf37 upstream.
When evaluating extended permissions, ignore unknown permissions instead
of calling BUG(). This commit ensures that future permissions can be
added without interfering with older kernels.
Cc: stable@vger.kernel.org
Fixes: fa1aa143ac ("selinux: extended permissions for ioctls")
Signed-off-by: Thiébaud Weksteen <tweek@google.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull integrity fixes from Mimi Zohar:
"One bug fix, one performance improvement, and the use of
static_assert:
- The bug fix addresses "only a cosmetic change" commit, which didn't
take into account the original 'ima' template definition.
- The performance improvement limits the atomic_read()"
* tag 'integrity-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
integrity: Use static_assert() to check struct sizes
evm: stop avoidably reading i_writecount in evm_file_release
ima: fix buffer overrun in ima_eventdigest_init_common
