path: root/security/apparmor
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2021-01-24apparmor: handle idmapped mountsChristian Brauner
The i_uid and i_gid are mostly used when logging for AppArmor. This is broken in a bunch of places where the global root id is reported instead of the i_uid or i_gid of the file. Nonetheless, be kind and log the mapped inode if we're coming from an idmapped mount. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: Signed-off-by: Christian Brauner <>
2021-01-24fs: make helpers idmap mount awareChristian Brauner
Extend some inode methods with an additional user namespace argument. A filesystem that is aware of idmapped mounts will receive the user namespace the mount has been marked with. This can be used for additional permission checking and also to enable filesystems to translate between uids and gids if they need to. We have implemented all relevant helpers in earlier patches. As requested we simply extend the exisiting inode method instead of introducing new ones. This is a little more code churn but it's mostly mechanical and doesnt't leave us with additional inode methods. Link: Cc: Christoph Hellwig <> Cc: David Howells <> Cc: Al Viro <> Cc: Reviewed-by: Christoph Hellwig <> Signed-off-by: Christian Brauner <>
2021-01-24xattr: handle idmapped mountsTycho Andersen
When interacting with extended attributes the vfs verifies that the caller is privileged over the inode with which the extended attribute is associated. For posix access and posix default extended attributes a uid or gid can be stored on-disk. Let the functions handle posix extended attributes on idmapped mounts. If the inode is accessed through an idmapped mount we need to map it according to the mount's user namespace. Afterwards the checks are identical to non-idmapped mounts. This has no effect for e.g. security xattrs since they don't store uids or gids and don't perform permission checks on them like posix acls do. Link: Cc: Christoph Hellwig <> Cc: David Howells <> Cc: Al Viro <> Cc: Reviewed-by: Christoph Hellwig <> Reviewed-by: James Morris <> Signed-off-by: Tycho Andersen <> Signed-off-by: Christian Brauner <>
2020-12-15apparmor: remove duplicate macro list_entry_is_head()Andy Shevchenko
Strangely I hadn't had noticed the existence of the list_entry_is_head() in apparmor code when added the same one in the list.h. Luckily it's fully identical and didn't break builds. In any case we don't need a duplicate anymore, thus remove it from apparmor code. Link: Fixes: e130816164e244 ("include/linux/list.h: add a macro to test if entry is pointing to the head") Signed-off-by: Andy Shevchenko <> Acked-by: John Johansen <> Cc: James Morris <> Cc: "Serge E . Hallyn " <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
2020-12-03security: add const qualifier to struct sock in various placesFlorian Westphal
A followup change to tcp_request_sock_op would have to drop the 'const' qualifier from the 'route_req' function as the 'security_inet_conn_request' call is moved there - and that function expects a 'struct sock *'. However, it turns out its also possible to add a const qualifier to security_inet_conn_request instead. Signed-off-by: Florian Westphal <> Acked-by: James Morris <> Signed-off-by: Jakub Kicinski <>
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] Signed-off-by: Gustavo A. R. Silva <>
2020-08-11Merge tag 'for-v5.9' of ↵Linus Torvalds
git:// Pull security subsystem updates from James Morris: "A couple of minor documentation updates only for this release" * tag 'for-v5.9' of git:// LSM: drop duplicated words in header file comments Replace HTTP links with HTTPS ones: security
2020-08-07mm, treewide: rename kzfree() to kfree_sensitive()Waiman Long
As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [ fs/crypto/inline_crypt.c needs linux/slab.h] [ fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <> Signed-off-by: Waiman Long <> Signed-off-by: Andrew Morton <> Acked-by: David Howells <> Acked-by: Michal Hocko <> Acked-by: Johannes Weiner <> Cc: Jarkko Sakkinen <> Cc: James Morris <> Cc: "Serge E. Hallyn" <> Cc: Joe Perches <> Cc: Matthew Wilcox <> Cc: David Rientjes <> Cc: Dan Carpenter <> Cc: "Jason A . Donenfeld" <> Link: Signed-off-by: Linus Torvalds <>
2020-08-06Replace HTTP links with HTTPS ones: securityAlexander A. Klimov
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov <> Acked-by: John Johansen <> Signed-off-by: James Morris <>
2020-07-21audit: purge audit_log_string from the intra-kernel audit APIRichard Guy Briggs
audit_log_string() was inteded to be an internal audit function and since there are only two internal uses, remove them. Purge all external uses of it by restructuring code to use an existing audit_log_format() or using audit_log_format(). Please see the upstream issue Signed-off-by: Richard Guy Briggs <> Signed-off-by: Paul Moore <>
2020-06-09Merge tag 'linux-kselftest-kunit-5.8-rc1' of ↵Linus Torvalds
git:// Pull Kunit updates from Shuah Khan: "This consists of: - Several config fragment fixes from Anders Roxell to improve test coverage. - Improvements to kunit run script to use defconfig as default and restructure the code for config/build/exec/parse from Vitor Massaru Iha and David Gow. - Miscellaneous documentation warn fix" * tag 'linux-kselftest-kunit-5.8-rc1' of git:// security: apparmor: default KUNIT_* fragments to KUNIT_ALL_TESTS fs: ext4: default KUNIT_* fragments to KUNIT_ALL_TESTS drivers: base: default KUNIT_* fragments to KUNIT_ALL_TESTS lib: Kconfig.debug: default KUNIT_* fragments to KUNIT_ALL_TESTS kunit: default KUNIT_* fragments to KUNIT_ALL_TESTS kunit: Kconfig: enable a KUNIT_ALL_TESTS fragment kunit: Fix TabError, remove defconfig code and handle when there is no kunitconfig kunit: use KUnit defconfig by default kunit: use --build_dir=.kunit as default Documentation: test.h - fix warnings kunit: kunit_tool: Separate out config/build/exec/parse
2020-06-07Merge tag 'apparmor-pr-2020-06-07' of ↵Linus Torvalds
git:// Pull apparmor updates from John Johansen: "Features: - Replace zero-length array with flexible-array - add a valid state flags check - add consistency check between state and dfa diff encode flags - add apparmor subdir to proc attr interface - fail unpack if profile mode is unknown - add outofband transition and use it in xattr match - ensure that dfa state tables have entries Cleanups: - Use true and false for bool variable - Remove semicolon - Clean code by removing redundant instructions - Replace two seq_printf() calls by seq_puts() in aa_label_seq_xprint() - remove duplicate check of xattrs on profile attachment - remove useless aafs_create_symlink Bug fixes: - Fix memory leak of profile proxy - fix introspection of of task mode for unconfined tasks - fix nnp subset test for unconfined - check/put label on apparmor_sk_clone_security()" * tag 'apparmor-pr-2020-06-07' of git:// apparmor: Fix memory leak of profile proxy apparmor: fix introspection of of task mode for unconfined tasks apparmor: check/put label on apparmor_sk_clone_security() apparmor: Use true and false for bool variable security/apparmor/label.c: Clean code by removing redundant instructions apparmor: Replace zero-length array with flexible-array apparmor: ensure that dfa state tables have entries apparmor: remove duplicate check of xattrs on profile attachment. apparmor: add outofband transition and use it in xattr match apparmor: fail unpack if profile mode is unknown apparmor: fix nnp subset test for unconfined apparmor: remove useless aafs_create_symlink apparmor: add proc subdir to attrs apparmor: add consistency check between state and dfa diff encode flags apparmor: add a valid state flags check AppArmor: Remove semicolon apparmor: Replace two seq_printf() calls by seq_puts() in aa_label_seq_xprint()
2020-06-07apparmor: Fix memory leak of profile proxyJohn Johansen
When the proxy isn't replaced and the profile is removed, the proxy is being leaked resulting in a kmemleak check message of unreferenced object 0xffff888077a3a490 (size 16): comm "apparmor_parser", pid 128041, jiffies 4322684109 (age 1097.028s) hex dump (first 16 bytes): 03 00 00 00 00 00 00 00 b0 92 fd 4b 81 88 ff ff ...........K.... backtrace: [<0000000084d5daf2>] aa_alloc_proxy+0x58/0xe0 [<00000000ecc0e21a>] aa_alloc_profile+0x159/0x1a0 [<000000004cc9ce15>] unpack_profile+0x275/0x1c40 [<000000007332b3ca>] aa_unpack+0x1e7/0x7e0 [<00000000e25e31bd>] aa_replace_profiles+0x18a/0x1d10 [<00000000350d9415>] policy_update+0x237/0x650 [<000000003fbf934e>] profile_load+0x122/0x160 [<0000000047f7b781>] vfs_write+0x139/0x290 [<000000008ad12358>] ksys_write+0xcd/0x170 [<000000001a9daa7b>] do_syscall_64+0x70/0x310 [<00000000b9efb0cf>] entry_SYSCALL_64_after_hwframe+0x49/0xb3 Make sure to cleanup the profile's embedded label which will result on the proxy being properly freed. Fixes: 637f688dc3dc ("apparmor: switch from profiles to using labels on contexts") Signed-off-by: John Johansen <>
2020-06-07apparmor: fix introspection of of task mode for unconfined tasksJohn Johansen
Fix two issues with introspecting the task mode. 1. If a task is attached to a unconfined profile that is not the ns->unconfined profile then. Mode the mode is always reported as - $ ps -Z LABEL PID TTY TIME CMD unconfined 1287 pts/0 00:00:01 bash test (-) 1892 pts/0 00:00:00 ps instead of the correct value of (unconfined) as shown below $ ps -Z LABEL PID TTY TIME CMD unconfined 2483 pts/0 00:00:01 bash test (unconfined) 3591 pts/0 00:00:00 ps 2. if a task is confined by a stack of profiles that are unconfined the output of label mode is again the incorrect value of (-) like above, instead of (unconfined). This is because the visibile profile count increment is skipped by the special casing of unconfined. Fixes: f1bd904175e8 ("apparmor: add the base fns() for domain labels") Signed-off-by: John Johansen <>
2020-06-07apparmor: check/put label on apparmor_sk_clone_security()Mauricio Faria de Oliveira
Currently apparmor_sk_clone_security() does not check for existing label/peer in the 'new' struct sock; it just overwrites it, if any (with another reference to the label of the source sock.) static void apparmor_sk_clone_security(const struct sock *sk, struct sock *newsk) { struct aa_sk_ctx *ctx = SK_CTX(sk); struct aa_sk_ctx *new = SK_CTX(newsk); new->label = aa_get_label(ctx->label); new->peer = aa_get_label(ctx->peer); } This might leak label references, which might overflow under load. Thus, check for and put labels, to prevent such errors. Note this is similarly done on: static int apparmor_socket_post_create(struct socket *sock, ...) ... if (sock->sk) { struct aa_sk_ctx *ctx = SK_CTX(sock->sk); aa_put_label(ctx->label); ctx->label = aa_get_label(label); } ... Context: ------- The label reference count leak is observed if apparmor_sock_graft() is called previously: this sets the 'ctx->label' field by getting a reference to the current label (later overwritten, without put.) static void apparmor_sock_graft(struct sock *sk, ...) { struct aa_sk_ctx *ctx = SK_CTX(sk); if (!ctx->label) ctx->label = aa_get_current_label(); } And that is the case on crypto/af_alg.c:af_alg_accept(): int af_alg_accept(struct sock *sk, struct socket *newsock, ...) ... struct sock *sk2; ... sk2 = sk_alloc(...); ... security_sock_graft(sk2, newsock); security_sk_clone(sk, sk2); ... Apparently both calls are done on their own right, especially for other LSMs, being introduced in 2010/2014, before apparmor socket mediation in 2017 (see commits [1,2,3,4]). So, it looks OK there! Let's fix the reference leak in apparmor. Test-case: --------- Exercise that code path enough to overflow label reference count. $ cat aa-refcnt-af_alg.c #include <stdio.h> #include <string.h> #include <unistd.h> #include <sys/socket.h> #include <linux/if_alg.h> int main() { int sockfd; struct sockaddr_alg sa; /* Setup the crypto API socket */ sockfd = socket(AF_ALG, SOCK_SEQPACKET, 0); if (sockfd < 0) { perror("socket"); return 1; } memset(&sa, 0, sizeof(sa)); sa.salg_family = AF_ALG; strcpy((char *) sa.salg_type, "rng"); strcpy((char *) sa.salg_name, "stdrng"); if (bind(sockfd, (struct sockaddr *) &sa, sizeof(sa)) < 0) { perror("bind"); return 1; } /* Accept a "connection" and close it; repeat. */ while (!close(accept(sockfd, NULL, 0))); return 0; } $ gcc -o aa-refcnt-af_alg aa-refcnt-af_alg.c $ ./aa-refcnt-af_alg <a few hours later> [ 9928.475953] refcount_t overflow at apparmor_sk_clone_security+0x37/0x70 in aa-refcnt-af_alg[1322], uid/euid: 1000/1000 ... [ 9928.507443] RIP: 0010:apparmor_sk_clone_security+0x37/0x70 ... [ 9928.514286] security_sk_clone+0x33/0x50 [ 9928.514807] af_alg_accept+0x81/0x1c0 [af_alg] [ 9928.516091] alg_accept+0x15/0x20 [af_alg] [ 9928.516682] SYSC_accept4+0xff/0x210 [ 9928.519609] SyS_accept+0x10/0x20 [ 9928.520190] do_syscall_64+0x73/0x130 [ 9928.520808] entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Note that other messages may be seen, not just overflow, depending on the value being incremented by kref_get(); on another run: [ 7273.182666] refcount_t: saturated; leaking memory. ... [ 7273.185789] refcount_t: underflow; use-after-free. Kprobes: ------- Using kprobe events to monitor sk -> sk_security -> label -> count (kref): Original v5.7 (one reference leak every iteration) ... (af_alg_accept+0x0/0x1c0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd2 ... (af_alg_release_parent+0x0/0xd0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd4 ... (af_alg_accept+0x0/0x1c0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd3 ... (af_alg_release_parent+0x0/0xd0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd5 ... (af_alg_accept+0x0/0x1c0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd4 ... (af_alg_release_parent+0x0/0xd0) label=0xffff8a0f36c25eb0 label_refcnt=0x11fd6 Patched v5.7 (zero reference leak per iteration) ... (af_alg_accept+0x0/0x1c0) label=0xffff9ff376c25eb0 label_refcnt=0x593 ... (af_alg_release_parent+0x0/0xd0) label=0xffff9ff376c25eb0 label_refcnt=0x594 ... (af_alg_accept+0x0/0x1c0) label=0xffff9ff376c25eb0 label_refcnt=0x593 ... (af_alg_release_parent+0x0/0xd0) label=0xffff9ff376c25eb0 label_refcnt=0x594 ... (af_alg_accept+0x0/0x1c0) label=0xffff9ff376c25eb0 label_refcnt=0x593 ... (af_alg_release_parent+0x0/0xd0) label=0xffff9ff376c25eb0 label_refcnt=0x594 Commits: ------- [1] commit 507cad355fc9 ("crypto: af_alg - Make sure sk_security is initialized on accept()ed sockets") [2] commit 4c63f83c2c2e ("crypto: af_alg - properly label AF_ALG socket") [3] commit 2acce6aa9f65 ("Networking") a.k.a ("crypto: af_alg - Avoid sock_graft call warning) [4] commit 56974a6fcfef ("apparmor: add base infastructure for socket mediation") Fixes: 56974a6fcfef ("apparmor: add base infastructure for socket mediation") Reported-by: Brian Moyles <> Signed-off-by: Mauricio Faria de Oliveira <> Signed-off-by: John Johansen <>
2020-06-04Merge branch 'exec-linus' of ↵Linus Torvalds
git:// Pull execve updates from Eric Biederman: "Last cycle for the Nth time I ran into bugs and quality of implementation issues related to exec that could not be easily be fixed because of the way exec is implemented. So I have been digging into exec and cleanup up what I can. I don't think I have exec sorted out enough to fix the issues I started with but I have made some headway this cycle with 4 sets of changes. - promised cleanups after introducing exec_update_mutex - trivial cleanups for exec - control flow simplifications - remove the recomputation of bprm->cred The net result is code that is a bit easier to understand and work with and a decrease in the number of lines of code (if you don't count the added tests)" * 'exec-linus' of git:// (24 commits) exec: Compute file based creds only once exec: Add a per bprm->file version of per_clear binfmt_elf_fdpic: fix execfd build regression selftests/exec: Add binfmt_script regression test exec: Remove recursion from search_binary_handler exec: Generic execfd support exec/binfmt_script: Don't modify bprm->buf and then return -ENOEXEC exec: Move the call of prepare_binprm into search_binary_handler exec: Allow load_misc_binary to call prepare_binprm unconditionally exec: Convert security_bprm_set_creds into security_bprm_repopulate_creds exec: Factor security_bprm_creds_for_exec out of security_bprm_set_creds exec: Teach prepare_exec_creds how exec treats uids & gids exec: Set the point of no return sooner exec: Move handling of the point of no return to the top level exec: Run sync_mm_rss before taking exec_update_mutex exec: Fix spelling of search_binary_handler in a comment exec: Move the comment from above de_thread to above unshare_sighand exec: Rename flush_old_exec begin_new_exec exec: Move most of setup_new_exec into flush_old_exec exec: In setup_new_exec cache current in the local variable me ...
2020-06-01security: apparmor: default KUNIT_* fragments to KUNIT_ALL_TESTSAnders Roxell
This makes it easier to enable all KUnit fragments. Adding 'if !KUNIT_ALL_TESTS' so individual tests can not be turned off. Therefore if KUNIT_ALL_TESTS is enabled that will hide the prompt in menuconfig. Reviewed-by: David Gow <> Signed-off-by: Anders Roxell <> Acked-by: John Johansen <> Signed-off-by: Shuah Khan <>
2020-05-24Merge git:// S. Miller
The MSCC bug fix in 'net' had to be slightly adjusted because the register accesses are done slightly differently in net-next. Signed-off-by: David S. Miller <>
2020-05-21apparmor: Fix use-after-free in aa_audit_rule_initNavid Emamdoost
In the implementation of aa_audit_rule_init(), when aa_label_parse() fails the allocated memory for rule is released using aa_audit_rule_free(). But after this release, the return statement tries to access the label field of the rule which results in use-after-free. Before releasing the rule, copy errNo and return it after release. Fixes: 52e8c38001d8 ("apparmor: Fix memory leak of rule on error exit path") Signed-off-by: Navid Emamdoost <> Signed-off-by: John Johansen <>
2020-05-21apparmor: Fix aa_label refcnt leak in policy_updateXiyu Yang
policy_update() invokes begin_current_label_crit_section(), which returns a reference of the updated aa_label object to "label" with increased refcount. When policy_update() returns, "label" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one exception handling path of policy_update(). When aa_may_manage_policy() returns not NULL, the refcnt increased by begin_current_label_crit_section() is not decreased, causing a refcnt leak. Fix this issue by jumping to "end_section" label when aa_may_manage_policy() returns not NULL. Fixes: 5ac8c355ae00 ("apparmor: allow introspecting the loaded policy pre internal transform") Signed-off-by: Xiyu Yang <> Signed-off-by: Xin Tan <> Signed-off-by: John Johansen <>
2020-05-21apparmor: fix potential label refcnt leak in aa_change_profileXiyu Yang
aa_change_profile() invokes aa_get_current_label(), which returns a reference of the current task's label. According to the comment of aa_get_current_label(), the returned reference must be put with aa_put_label(). However, when the original object pointed by "label" becomes unreachable because aa_change_profile() returns or a new object is assigned to "label", reference count increased by aa_get_current_label() is not decreased, causing a refcnt leak. Fix this by calling aa_put_label() before aa_change_profile() return and dropping unnecessary aa_get_current_label(). Fixes: 9fcf78cca198 ("apparmor: update domain transitions that are subsets of confinement at nnp") Signed-off-by: Xiyu Yang <> Signed-off-by: Xin Tan <> Signed-off-by: John Johansen <>
2020-05-20exec: Factor security_bprm_creds_for_exec out of security_bprm_set_credsEric W. Biederman
Today security_bprm_set_creds has several implementations: apparmor_bprm_set_creds, cap_bprm_set_creds, selinux_bprm_set_creds, smack_bprm_set_creds, and tomoyo_bprm_set_creds. Except for cap_bprm_set_creds they all test bprm->called_set_creds and return immediately if it is true. The function cap_bprm_set_creds ignores bprm->calld_sed_creds entirely. Create a new LSM hook security_bprm_creds_for_exec that is called just before prepare_binprm in __do_execve_file, resulting in a LSM hook that is called exactly once for the entire of exec. Modify the bits of security_bprm_set_creds that only want to be called once per exec into security_bprm_creds_for_exec, leaving only cap_bprm_set_creds behind. Remove bprm->called_set_creds all of it's former users have been moved to security_bprm_creds_for_exec. Add or upate comments a appropriate to bring them up to date and to reflect this change. Link: Acked-by: Linus Torvalds <> Acked-by: Casey Schaufler <> # For the LSM and Smack bits Reviewed-by: Kees Cook <> Signed-off-by: "Eric W. Biederman" <>
2020-05-15apparmor: Use true and false for bool variableZou Wei
Fixes coccicheck warnings: security/apparmor/file.c:162:9-10: WARNING: return of 0/1 in function 'is_deleted' with return type bool security/apparmor/file.c:362:9-10: WARNING: return of 0/1 in function 'xindex_is_subset' with return type bool security/apparmor/policy_unpack.c:246:9-10: WARNING: return of 0/1 in function 'unpack_X' with return type bool security/apparmor/policy_unpack.c:292:9-10: WARNING: return of 0/1 in function 'unpack_nameX' with return type bool security/apparmor/policy_unpack.c:646:8-9: WARNING: return of 0/1 in function 'unpack_rlimits' with return type bool security/apparmor/policy_unpack.c:604:8-9: WARNING: return of 0/1 in function 'unpack_secmark' with return type bool security/apparmor/policy_unpack.c:538:8-9: WARNING: return of 0/1 in function 'unpack_trans_table' with return type bool security/apparmor/policy_unpack.c:327:9-10: WARNING: return of 0/1 in function 'unpack_u32' with return type bool security/apparmor/policy_unpack.c:345:9-10: WARNING: return of 0/1 in function 'unpack_u64' with return type bool security/apparmor/policy_unpack.c:309:9-10: WARNING: return of 0/1 in function 'unpack_u8' with return type bool security/apparmor/policy_unpack.c:568:8-9: WARNING: return of 0/1 in function 'unpack_xattrs' with return type bool security/apparmor/policy_unpack.c:1007:10-11: WARNING: return of 0/1 in function 'verify_dfa_xindex' with return type bool security/apparmor/policy_unpack.c:997:9-10: WARNING: return of 0/1 in function 'verify_xindex' with return type bool Reported-by: Hulk Robot <> Signed-off-by: Zou Wei <> Signed-off-by: John Johansen <>
2020-05-15security/apparmor/label.c: Clean code by removing redundant instructionsMateusz Nosek
Previously 'label->proxy->label' value checking and conditional reassigning were done twice in the same function. The second one is redundant and can be removed. Signed-off-by: Mateusz Nosek <> Signed-off-by: John Johansen <>
2020-05-15apparmor: Replace zero-length array with flexible-arrayGustavo A. R. Silva
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member conversions) will also help to get completely rid of those sorts of issues. This issue was found with the help of Coccinelle. [1] [2] [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <> Signed-off-by: John Johansen <>
2020-04-27sysctl: pass kernel pointers to ->proc_handlerChristoph Hellwig
Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: Christoph Hellwig <> Acked-by: Andrey Ignatov <> Signed-off-by: Al Viro <>
2020-04-08apparmor: ensure that dfa state tables have entriesJohn Johansen
Currently it is possible to specify a state machine table with 0 length, this is not valid as optional tables are specified by not defining the table as present. Further this allows by-passing the base tables range check against the next/check tables. Fixes: d901d6a298dc ("apparmor: dfa split verification of table headers") Reported-by: Mike Salvatore <> Signed-off-by: John Johansen <>
2020-03-25.gitignore: add SPDX License IdentifierMasahiro Yamada
Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada <> Signed-off-by: Greg Kroah-Hartman <>
2020-03-25.gitignore: remove too obvious commentsMasahiro Yamada
Some .gitignore files have comments like "Generated files", "Ignore generated files" at the header part, but they are too obvious. Signed-off-by: Masahiro Yamada <> Signed-off-by: Greg Kroah-Hartman <>
2020-01-29Merge tag 'linux-kselftest-5.6-rc1-kunit' of ↵Linus Torvalds
git:// Pull Kselftest kunit updates from Shuah Khan: "This kunit update consists of: - Support for building kunit as a module from Alan Maguire - AppArmor KUnit tests for policy unpack from Mike Salvatore" * tag 'linux-kselftest-5.6-rc1-kunit' of git:// kunit: building kunit as a module breaks allmodconfig kunit: update documentation to describe module-based build kunit: allow kunit to be loaded as a module kunit: remove timeout dependence on sysctl_hung_task_timeout_seconds kunit: allow kunit tests to be loaded as a module kunit: hide unexported try-catch interface in try-catch-impl.h kunit: move string-stream.h to lib/kunit apparmor: add AppArmor KUnit tests for policy unpack
2020-01-29Merge branch 'work.openat2' of ↵Linus Torvalds
git:// Pull openat2 support from Al Viro: "This is the openat2() series from Aleksa Sarai. I'm afraid that the rest of namei stuff will have to wait - it got zero review the last time I'd posted #work.namei, and there had been a leak in the posted series I'd caught only last weekend. I was going to repost it on Monday, but the window opened and the odds of getting any review during that... Oh, well. Anyway, openat2 part should be ready; that _did_ get sane amount of review and public testing, so here it comes" From Aleksa's description of the series: "For a very long time, extending openat(2) with new features has been incredibly frustrating. This stems from the fact that openat(2) is possibly the most famous counter-example to the mantra "don't silently accept garbage from userspace" -- it doesn't check whether unknown flags are present[1]. This means that (generally) the addition of new flags to openat(2) has been fraught with backwards-compatibility issues (O_TMPFILE has to be defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old kernels gave errors, since it's insecure to silently ignore the flag[2]). All new security-related flags therefore have a tough road to being added to openat(2). Furthermore, the need for some sort of control over VFS's path resolution (to avoid malicious paths resulting in inadvertent breakouts) has been a very long-standing desire of many userspace applications. This patchset is a revival of Al Viro's old AT_NO_JUMPS[3] patchset (which was a variant of David Drysdale's O_BENEATH patchset[4] which was a spin-off of the Capsicum project[5]) with a few additions and changes made based on the previous discussion within [6] as well as others I felt were useful. In line with the conclusions of the original discussion of AT_NO_JUMPS, the flag has been split up into separate flags. However, instead of being an openat(2) flag it is provided through a new syscall openat2(2) which provides several other improvements to the openat(2) interface (see the patch description for more details). The following new LOOKUP_* flags are added: LOOKUP_NO_XDEV: Blocks all mountpoint crossings (upwards, downwards, or through absolute links). Absolute pathnames alone in openat(2) do not trigger this. Magic-link traversal which implies a vfsmount jump is also blocked (though magic-link jumps on the same vfsmount are permitted). LOOKUP_NO_MAGICLINKS: Blocks resolution through /proc/$pid/fd-style links. This is done by blocking the usage of nd_jump_link() during resolution in a filesystem. The term "magic-links" is used to match with the only reference to these links in Documentation/, but I'm happy to change the name. It should be noted that this is different to the scope of ~LOOKUP_FOLLOW in that it applies to all path components. However, you can do openat2(NO_FOLLOW|NO_MAGICLINKS) on a magic-link and it will *not* fail (assuming that no parent component was a magic-link), and you will have an fd for the magic-link. In order to correctly detect magic-links, the introduction of a new LOOKUP_MAGICLINK_JUMPED state flag was required. LOOKUP_BENEATH: Disallows escapes to outside the starting dirfd's tree, using techniques such as ".." or absolute links. Absolute paths in openat(2) are also disallowed. Conceptually this flag is to ensure you "stay below" a certain point in the filesystem tree -- but this requires some additional to protect against various races that would allow escape using "..". Currently LOOKUP_BENEATH implies LOOKUP_NO_MAGICLINKS, because it can trivially beam you around the filesystem (breaking the protection). In future, there might be similar safety checks done as in LOOKUP_IN_ROOT, but that requires more discussion. In addition, two new flags are added that expand on the above ideas: LOOKUP_NO_SYMLINKS: Does what it says on the tin. No symlink resolution is allowed at all, including magic-links. Just as with LOOKUP_NO_MAGICLINKS this can still be used with NOFOLLOW to open an fd for the symlink as long as no parent path had a symlink component. LOOKUP_IN_ROOT: This is an extension of LOOKUP_BENEATH that, rather than blocking attempts to move past the root, forces all such movements to be scoped to the starting point. This provides chroot(2)-like protection but without the cost of a chroot(2) for each filesystem operation, as well as being safe against race attacks that chroot(2) is not. If a race is detected (as with LOOKUP_BENEATH) then an error is generated, and similar to LOOKUP_BENEATH it is not permitted to cross magic-links with LOOKUP_IN_ROOT. The primary need for this is from container runtimes, which currently need to do symlink scoping in userspace[7] when opening paths in a potentially malicious container. There is a long list of CVEs that could have bene mitigated by having RESOLVE_THIS_ROOT (such as CVE-2017-1002101, CVE-2017-1002102, CVE-2018-15664, and CVE-2019-5736, just to name a few). In order to make all of the above more usable, I'm working on libpathrs[8] which is a C-friendly library for safe path resolution. It features a userspace-emulated backend if the kernel doesn't support openat2(2). Hopefully we can get userspace to switch to using it, and thus get openat2(2) support for free once it's ready. Future work would include implementing things like RESOLVE_NO_AUTOMOUNT and possibly a RESOLVE_NO_REMOTE (to allow programs to be sure they don't hit DoSes though stale NFS handles)" * 'work.openat2' of git:// Documentation: path-lookup: include new LOOKUP flags selftests: add openat2(2) selftests open: introduce openat2(2) syscall namei: LOOKUP_{IN_ROOT,BENEATH}: permit limited ".." resolution namei: LOOKUP_IN_ROOT: chroot-like scoped resolution namei: LOOKUP_BENEATH: O_BENEATH-like scoped resolution namei: LOOKUP_NO_XDEV: block mountpoint crossing namei: LOOKUP_NO_MAGICLINKS: block magic-link resolution namei: LOOKUP_NO_SYMLINKS: block symlink resolution namei: allow set_root() to produce errors namei: allow nd_jump_link() to produce errors nsfs: clean-up ns_get_path() signature to return int namei: only return -ECHILD from follow_dotdot_rcu()
2020-01-21apparmor: remove duplicate check of xattrs on profile attachment.John Johansen
The second check to ensure the xattrs are present and checked is unneeded as this is already done in the profile attachment xmatch. Signed-off-by: John Johansen <>
2020-01-21apparmor: add outofband transition and use it in xattr matchJohn Johansen
There are cases where the a special out of band transition that can not be triggered by input is useful in separating match conditions in the dfa encoding. The null_transition is currently used as an out of band transition for match conditions that can not contain a \0 in their input but apparmor needs an out of band transition for cases where the match condition is allowed to contain any input character. Achieve this by allowing for an explicit transition out of input range that can only be triggered by code. Signed-off-by: John Johansen <>
2020-01-21apparmor: fail unpack if profile mode is unknownJohn Johansen
Profile unpack should fail if the profile mode is not a mode that the kernel understands. Signed-off-by: John Johansen <>
2020-01-21apparmor: fix nnp subset test for unconfinedJohn Johansen
The subset test is not taking into account the unconfined exception which will cause profile transitions in the stacked confinement case to fail when no_new_privs is applied. This fixes a regression introduced in the fix for BugLink: Signed-off-by: John Johansen <>
2020-01-21apparmor: remove useless aafs_create_symlinkJohn Johansen
commit 1180b4c757aa ("apparmor: fix dangling symlinks to policy rawdata after replacement") reworked how the rawdata symlink is handled but failedto remove aafs_create_symlink which was reduced to a useles stub. Fixes: 1180b4c757aa ("apparmor: fix dangling symlinks to policy rawdata after replacement") Reported-by: Al Viro <> Signed-off-by: John Johansen <>
2020-01-18apparmor: add consistency check between state and dfa diff encode flagsJohn Johansen
Check that a states diff encode flag is only set if diff encode is enabled in the dfa header. Signed-off-by: John Johansen <>
2020-01-18apparmor: add a valid state flags checkJohn Johansen
Add a check to ensure only known state flags are set on each state in the dfa. Signed-off-by: John Johansen <>
2020-01-18AppArmor: Remove semicolonVasyl Gomonovych
Remove unneeded semicolon Signed-off-by: Vasyl Gomonovych <> Signed-off-by: John Johansen <>
2020-01-18apparmor: Replace two seq_printf() calls by seq_puts() in aa_label_seq_xprint()Markus Elfring
Two strings which did not contain a data format specification should be put into a sequence. Thus use the corresponding function “seq_puts”. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <> Signed-off-by: John Johansen <>
2020-01-10kunit: building kunit as a module breaks allmodconfigAlan Maguire
kunit tests that do not support module build should depend on KUNIT=y rather than just KUNIT in Kconfig, otherwise they will trigger compilation errors for "make allmodconfig" builds. Fixes: 9fe124bf1b77 ("kunit: allow kunit to be loaded as a module") Reported-by: Stephen Rothwell <> Signed-off-by: Alan Maguire <> Signed-off-by: Shuah Khan <>
2020-01-09apparmor: add AppArmor KUnit tests for policy unpackMike Salvatore
Add KUnit tests to test AppArmor unpacking of userspace policies. AppArmor uses a serialized binary format for loading policies. To find policy format documentation see Documentation/admin-guide/LSM/apparmor.rst. In order to write the tests against the policy unpacking code, some static functions needed to be exposed for testing purposes. One of the goals of this patch is to establish a pattern for which testing these kinds of functions should be done in the future. Signed-off-by: Brendan Higgins <> Signed-off-by: Mike Salvatore <> Acked-by: John Johansen <> Reviewed-by: Kees Cook <> Signed-off-by: Shuah Khan <>
2020-01-04apparmor: fix aa_xattrs_match() may sleep while holding a RCU lockJohn Johansen
aa_xattrs_match() is unfortunately calling vfs_getxattr_alloc() from a context protected by an rcu_read_lock. This can not be done as vfs_getxattr_alloc() may sleep regardles of the gfp_t value being passed to it. Fix this by breaking the rcu_read_lock on the policy search when the xattr match feature is requested and restarting the search if a policy changes occur. Fixes: 8e51f9087f40 ("apparmor: Add support for attaching profiles via xattr, presence and value") Reported-by: Jia-Ju Bai <> Reported-by: Al Viro <> Signed-off-by: John Johansen <>
2020-01-02apparmor: only get a label reference if the fast path check failsJohn Johansen
The common fast path check can be done under rcu_read_lock() and doesn't need a reference count on the label. Only take a reference count if entering the slow path. Fixes reported hackbench regression - sha1 79e178a57dae ("Merge tag 'apparmor-pr-2019-12-03' of git://") hackbench -l (256000/#grp) -g #grp 128 groups 19.679 ±0.90% - previous sha1 01d1dff64662 ("Merge tag 's390-5.5-2' of git://") hackbench -l (256000/#grp) -g #grp 128 groups 3.1689 ±3.04% Reported-by: Vincent Guittot <> Tested-by: Vincent Guittot <> Tested-by: Sebastian Andrzej Siewior <> Fixes: bce4e7e9c45e ("apparmor: reduce rcu_read_lock scope for aa_file_perm mediation") Signed-off-by: John Johansen <>
2020-01-02apparmor: fix bind mounts aborting with -ENOMEMPatrick Steinhardt
With commit df323337e507 ("apparmor: Use a memory pool instead per-CPU caches, 2019-05-03"), AppArmor code was converted to use memory pools. In that conversion, a bug snuck into the code that polices bind mounts that causes all bind mounts to fail with -ENOMEM, as we erroneously error out if `aa_get_buffer` returns a pointer instead of erroring out when it does _not_ return a valid pointer. Fix the issue by correctly checking for valid pointers returned by `aa_get_buffer` to fix bind mounts with AppArmor. Fixes: df323337e507 ("apparmor: Use a memory pool instead per-CPU caches") Signed-off-by: Patrick Steinhardt <> Signed-off-by: John Johansen <>
2019-12-08namei: allow nd_jump_link() to produce errorsAleksa Sarai
In preparation for LOOKUP_NO_MAGICLINKS, it's necessary to add the ability for nd_jump_link() to return an error which the corresponding get_link() caller must propogate back up to the VFS. Suggested-by: Al Viro <> Signed-off-by: Aleksa Sarai <> Signed-off-by: Al Viro <>
2019-12-03Merge tag 'apparmor-pr-2019-12-03' of ↵Linus Torvalds
git:// Pull apparmor updates from John Johansen: "Features: - increase left match history buffer size to provide improved conflict resolution in overlapping execution rules. - switch buffer allocation to use a memory pool and GFP_KERNEL where possible. - add compression of policy blobs to reduce memory usage. Cleanups: - fix spelling mistake "immutible" -> "immutable" Bug fixes: - fix unsigned len comparison in update_for_len macro - fix sparse warning for type-casting of current->real_cred" * tag 'apparmor-pr-2019-12-03' of git:// apparmor: make it so work buffers can be allocated from atomic context apparmor: reduce rcu_read_lock scope for aa_file_perm mediation apparmor: fix wrong buffer allocation in aa_new_mount apparmor: fix unsigned len comparison with less than zero apparmor: increase left match history buffer size apparmor: Switch to GFP_KERNEL where possible apparmor: Use a memory pool instead per-CPU caches apparmor: Force type-casting of current->real_cred apparmor: fix spelling mistake "immutible" -> "immutable" apparmor: fix blob compression when ns is forced on a policy load apparmor: fix missing ZLIB defines apparmor: fix blob compression build failure on ppc apparmor: Initial implementation of raw policy blob compression
2019-11-22apparmor: make it so work buffers can be allocated from atomic contextJohn Johansen
In some situations AppArmor needs to be able to use its work buffers from atomic context. Add the ability to specify when in atomic context and hold a set of work buffers in reserve for atomic context to reduce the chance that a large work buffer allocation will need to be done. Fixes: df323337e507 ("apparmor: Use a memory pool instead per-CPU caches") Signed-off-by: John Johansen <>
2019-11-22apparmor: reduce rcu_read_lock scope for aa_file_perm mediationJohn Johansen
Now that the buffers allocation has changed and no longer needs the full mediation under an rcu_read_lock, reduce the rcu_read_lock scope to only where it is necessary. Fixes: df323337e507 ("apparmor: Use a memory pool instead per-CPU caches") Signed-off-by: John Johansen <>
2019-11-22apparmor: fix wrong buffer allocation in aa_new_mountJohn Johansen
Fix the following trace caused by the dev_path buffer not being allocated. [ 641.044262] AppArmor WARN match_mnt: ((devpath && !devbuffer)): [ 641.044284] WARNING: CPU: 1 PID: 30709 at ../security/apparmor/mount.c:385 match_mnt+0x133/0x180 [ 641.044286] Modules linked in: snd_hda_codec_generic ledtrig_audio snd_hda_intel snd_hda_codec snd_hda_core qxl ttm snd_hwdep snd_pcm drm_kms_helper snd_seq_midi snd_seq_midi_event drm snd_rawmidi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel iptable_mangle aesni_intel aes_x86_64 xt_tcpudp crypto_simd snd_seq cryptd bridge stp llc iptable_filter glue_helper snd_seq_device snd_timer joydev input_leds snd serio_raw fb_sys_fops 9pnet_virtio 9pnet syscopyarea sysfillrect soundcore sysimgblt qemu_fw_cfg mac_hid sch_fq_codel parport_pc ppdev lp parport ip_tables x_tables autofs4 8139too psmouse 8139cp i2c_piix4 pata_acpi mii floppy [ 641.044318] CPU: 1 PID: 30709 Comm: mount Tainted: G D W 5.1.0-rc4+ #223 [ 641.044320] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 641.044323] RIP: 0010:match_mnt+0x133/0x180 [ 641.044325] Code: 41 5d 41 5e 41 5f c3 48 8b 4c 24 18 eb b1 48 c7 c6 08 84 26 83 48 c7 c7 f0 56 54 83 4c 89 54 24 08 48 89 14 24 e8 7d d3 bb ff <0f> 0b 4c 8b 54 24 08 48 8b 14 24 e9 25 ff ff ff 48 c7 c6 08 84 26 [ 641.044327] RSP: 0018:ffffa9b34ac97d08 EFLAGS: 00010282 [ 641.044329] RAX: 0000000000000000 RBX: ffff9a86725a8558 RCX: 0000000000000000 [ 641.044331] RDX: 0000000000000002 RSI: 0000000000000001 RDI: 0000000000000246 [ 641.044333] RBP: ffffa9b34ac97db0 R08: 0000000000000000 R09: 0000000000000000 [ 641.044334] R10: 0000000000000000 R11: 00000000000077f5 R12: 0000000000000000 [ 641.044336] R13: ffffa9b34ac97e98 R14: ffff9a865e000008 R15: ffff9a86c4cf42b8 [ 641.044338] FS: 00007fab73969740(0000) GS:ffff9a86fbb00000(0000) knlGS:0000000000000000 [ 641.044340] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 641.044342] CR2: 000055f90bc62035 CR3: 00000000aab5f006 CR4: 00000000003606e0 [ 641.044346] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 641.044348] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 641.044349] Call Trace: [ 641.044355] aa_new_mount+0x119/0x2c0 [ 641.044363] apparmor_sb_mount+0xd4/0x430 [ 641.044367] security_sb_mount+0x46/0x70 [ 641.044372] do_mount+0xbb/0xeb0 [ 641.044377] ? memdup_user+0x4b/0x70 [ 641.044380] ksys_mount+0x7e/0xd0 [ 641.044384] __x64_sys_mount+0x21/0x30 [ 641.044388] do_syscall_64+0x5a/0x1a0 [ 641.044392] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 641.044394] RIP: 0033:0x7fab73a8790a [ 641.044397] Code: 48 8b 0d 89 85 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 56 85 0c 00 f7 d8 64 89 01 48 [ 641.044399] RSP: 002b:00007ffe0ffe4238 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [ 641.044401] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fab73a8790a [ 641.044429] RDX: 000055f90bc6203b RSI: 00007ffe0ffe57b1 RDI: 00007ffe0ffe57a5 [ 641.044431] RBP: 00007ffe0ffe4250 R08: 0000000000000000 R09: 00007fab73b51d80 [ 641.044433] R10: 00000000c0ed0004 R11: 0000000000000206 R12: 000055f90bc610b0 [ 641.044434] R13: 00007ffe0ffe4330 R14: 0000000000000000 R15: 0000000000000000 [ 641.044457] irq event stamp: 0 [ 641.044460] hardirqs last enabled at (0): [<0000000000000000>] (null) [ 641.044463] hardirqs last disabled at (0): [<ffffffff82290114>] copy_process.part.30+0x734/0x23f0 [ 641.044467] softirqs last enabled at (0): [<ffffffff82290114>] copy_process.part.30+0x734/0x23f0 [ 641.044469] softirqs last disabled at (0): [<0000000000000000>] (null) [ 641.044470] ---[ end trace c0d54bdacf6af6b2 ]--- Fixes: df323337e507 ("apparmor: Use a memory pool instead per-CPU caches") Signed-off-by: John Johansen <>