kernel/linux.git/security/integrity/ima, branch v6.1.168

ima: Handle error code returned by ima_filter_rule_match()

2026-01-11T14:18:28+00:00

[ Upstream commit 738c9738e690f5cea24a3ad6fd2d9a323cf614f6 ] 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: 4af4662fa4a9d ("integrity: IMA policy") Signed-off-by: Zhao Yipeng Reviewed-by: Roberto Sassu Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

ima: fix buffer overrun in ima_eventdigest_init_common

2024-11-22T14:37:31+00:00

commit 923168a0631bc42fffd55087b337b1b6c54dcff5 upstream. Function ima_eventdigest_init() calls ima_eventdigest_init_common() with HASH_ALGO__LAST which is then used to access the array hash_digest_size[] leading to buffer overrun. Have a conditional statement to handle this. Fixes: 9fab303a2cb3 ("ima: fix violation measurement list record") Signed-off-by: Samasth Norway Ananda Tested-by: Enrico Bravi (PhD at polito.it) Cc: stable@vger.kernel.org # 5.19+ Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

ima: Avoid blocking in RCU read-side critical section

2024-07-11T10:47:16+00:00

commit 9a95c5bfbf02a0a7f5983280fe284a0ff0836c34 upstream. 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 Acked-by: John Johansen Reviewed-by: Mimi Zohar Reviewed-by: Casey Schaufler [PM: fixed missing comment, long lines, !CONFIG_IMA_LSM_RULES case] Signed-off-by: Paul Moore Signed-off-by: Roberto Sassu Signed-off-by: Greg Kroah-Hartman

ima: Fix use-after-free on a dentry's dname.name

2024-07-05T07:31:51+00:00

[ Upstream commit be84f32bb2c981ca670922e047cdde1488b233de ] ->d_name.name can change on rename and the earlier value can be freed; there are conditions sufficient to stabilize it (->d_lock on dentry, ->d_lock on its parent, ->i_rwsem exclusive on the parent's inode, rename_lock), but none of those are met at any of the sites. Take a stable snapshot of the name instead. Link: https://lore.kernel.org/all/20240202182732.GE2087318@ZenIV/ Signed-off-by: Al Viro Signed-off-by: Stefan Berger Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

ima: detect changes to the backing overlay file

2023-11-28T17:07:12+00:00

commit b836c4d29f2744200b2af41e14bf50758dddc818 upstream. Commit 18b44bc5a672 ("ovl: Always reevaluate the file signature for IMA") forced signature re-evaulation on every file access. Instead of always re-evaluating the file's integrity, detect a change to the backing file, by comparing the cached file metadata with the backing file's metadata. Verifying just the i_version has not changed is insufficient. In addition save and compare the i_ino and s_dev as well. Reviewed-by: Amir Goldstein Tested-by: Eric Snowberg Tested-by: Raul E Rangel Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

ima: rework CONFIG_IMA dependency block

2023-10-10T20:00:41+00:00

[ Upstream commit 91e326563ee34509c35267808a4b1b3ea3db62a8 ] Changing the direct dependencies of IMA_BLACKLIST_KEYRING and IMA_LOAD_X509 caused them to no longer depend on IMA, but a a configuration without IMA results in link failures: arm-linux-gnueabi-ld: security/integrity/iint.o: in function `integrity_load_keys': iint.c:(.init.text+0xd8): undefined reference to `ima_load_x509' aarch64-linux-ld: security/integrity/digsig_asymmetric.o: in function `asymmetric_verify': digsig_asymmetric.c:(.text+0x104): undefined reference to `ima_blacklist_keyring' Adding explicit dependencies on IMA would fix this, but a more reliable way to do this is to enclose the entire Kconfig file in an 'if IMA' block. This also allows removing the existing direct dependencies. Fixes: be210c6d3597f ("ima: Finish deprecation of IMA_TRUSTED_KEYRING Kconfig") Signed-off-by: Arnd Bergmann Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

ima: Finish deprecation of IMA_TRUSTED_KEYRING Kconfig

2023-10-10T20:00:41+00:00

[ Upstream commit be210c6d3597faf330cb9af33b9f1591d7b2a983 ] The removal of IMA_TRUSTED_KEYRING made IMA_LOAD_X509 and IMA_BLACKLIST_KEYRING unavailable because the latter two depend on the former. Since IMA_TRUSTED_KEYRING was deprecated in favor of INTEGRITY_TRUSTED_KEYRING use it as a dependency for the two Kconfigs affected by the deprecation. Fixes: 5087fd9e80e5 ("ima: Remove deprecated IMA_TRUSTED_KEYRING Kconfig") Signed-off-by: Oleksandr Tymoshenko Reviewed-by: Nayna Jain Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

ima: Remove deprecated IMA_TRUSTED_KEYRING Kconfig

2023-09-13T07:42:42+00:00

[ Upstream commit 5087fd9e80e539d2163accd045b73da64de7de95 ] Time to remove "IMA_TRUSTED_KEYRING". Fixes: f4dc37785e9b ("integrity: define '.evm' as a builtin 'trusted' keyring") # v4.5+ Signed-off-by: Nayna Jain Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

ima: Fix build warnings

2023-07-19T14:21:03+00:00

[ Upstream commit 95526d13038c2bbddd567a4d8e39fac42484e182 ] Fix build warnings (function parameters description) for ima_collect_modsig(), ima_match_policy() and ima_parse_add_rule(). Fixes: 15588227e086 ("ima: Collect modsig") # v5.4+ Fixes: 2fe5d6def167 ("ima: integrity appraisal extension") # v5.14+ Fixes: 4af4662fa4a9 ("integrity: IMA policy") # v3.2+ Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

IMA: allow/fix UML builds

2023-05-11T14:02:59+00:00

commit 644f17412f5acf01a19af9d04a921937a2bc86c6 upstream. UML supports HAS_IOMEM since 0bbadafdc49d (um: allow disabling NO_IOMEM). Current IMA build on UML fails on allmodconfig (with TCG_TPM=m): ld: security/integrity/ima/ima_queue.o: in function `ima_add_template_entry': ima_queue.c:(.text+0x2d9): undefined reference to `tpm_pcr_extend' ld: security/integrity/ima/ima_init.o: in function `ima_init': ima_init.c:(.init.text+0x43f): undefined reference to `tpm_default_chip' ld: security/integrity/ima/ima_crypto.o: in function `ima_calc_boot_aggregate_tfm': ima_crypto.c:(.text+0x1044): undefined reference to `tpm_pcr_read' ld: ima_crypto.c:(.text+0x10d8): undefined reference to `tpm_pcr_read' Modify the IMA Kconfig entry so that it selects TCG_TPM if HAS_IOMEM is set, regardless of the UML Kconfig setting. This updates TCG_TPM from =m to =y and fixes the linker errors. Fixes: f4a0391dfa91 ("ima: fix Kconfig dependencies") Cc: Stable # v5.14+ Signed-off-by: Randy Dunlap Cc: Fabio Estevam Cc: Richard Weinberger Cc: Anton Ivanov Cc: Johannes Berg Cc: linux-um@lists.infradead.org Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman