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* Merge tag 'apparmor-pr-2020-06-07' of ↵Linus Torvalds2020-06-0811-119/+185
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor 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://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: 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()
| * apparmor: Fix memory leak of profile proxyJohn Johansen2020-06-073-6/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <john.johansen@canonical.com>
| * apparmor: fix introspection of of task mode for unconfined tasksJohn Johansen2020-06-071-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <john.johansen@canonical.com>
| * apparmor: check/put label on apparmor_sk_clone_security()Mauricio Faria de Oliveira2020-06-071-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <bmoyles@netflix.com> Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com> Signed-off-by: John Johansen <john.johansen@canonical.com>
| * apparmor: Use true and false for bool variableZou Wei2020-05-152-33/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <hulkci@huawei.com> Signed-off-by: Zou Wei <zou_wei@huawei.com> Signed-off-by: John Johansen <john.johansen@canonical.com>
| * security/apparmor/label.c: Clean code by removing redundant instructionsMateusz Nosek2020-05-151-6/+0
| | | | | | | | | | | | | | | | | | 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 <mateusznosek0@gmail.com> Signed-off-by: John Johansen <john.johansen@canonical.com>
| * apparmor: Replace zero-length array with flexible-arrayGustavo A. R. Silva2020-05-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: John Johansen <john.johansen@canonical.com>
| * apparmor: ensure that dfa state tables have entriesJohn Johansen2020-04-081-0/+5
| | | | | | | | | | | | | | | | | | | | | | 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 <mike.salvatore@canonical.com> Signed-off-by: John Johansen <john.johansen@canonical.com>
| * apparmor: remove duplicate check of xattrs on profile attachment.John Johansen2020-01-211-17/+0
| | | | | | | | | | | | | | 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 <john.johansen@canonical.com>
| * apparmor: add outofband transition and use it in xattr matchJohn Johansen2020-01-214-7/+62
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <john.johansen@canonical.com>
| * apparmor: fail unpack if profile mode is unknownJohn Johansen2020-01-211-0/+4
| | | | | | | | | | | | | | Profile unpack should fail if the profile mode is not a mode that the kernel understands. Signed-off-by: John Johansen <john.johansen@canonical.com>
| * apparmor: fix nnp subset test for unconfinedJohn Johansen2020-01-213-4/+39
| | | | | | | | | | | | | | | | | | | | | | | | 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 https://bugs.launchpad.net/bugs/1839037 BugLink: https://bugs.launchpad.net/bugs/1844186 Signed-off-by: John Johansen <john.johansen@canonical.com>
| * apparmor: remove useless aafs_create_symlinkJohn Johansen2020-01-211-41/+9
| | | | | | | | | | | | | | | | | | | | | | 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 <viro@zeniv.linux.org.uk> Signed-off-by: John Johansen <john.johansen@canonical.com>
| * apparmor: add consistency check between state and dfa diff encode flagsJohn Johansen2020-01-191-0/+6
| | | | | | | | | | | | | | Check that a states diff encode flag is only set if diff encode is enabled in the dfa header. Signed-off-by: John Johansen <john.johansen@canonical.com>
| * apparmor: add a valid state flags checkJohn Johansen2020-01-192-0/+8
| | | | | | | | | | | | | | Add a check to ensure only known state flags are set on each state in the dfa. Signed-off-by: John Johansen <john.johansen@canonical.com>
| * AppArmor: Remove semicolonVasyl Gomonovych2020-01-191-1/+1
| | | | | | | | | | | | | | Remove unneeded semicolon Signed-off-by: Vasyl Gomonovych <gomonovych@gmail.com> Signed-off-by: John Johansen <john.johansen@canonical.com>
| * apparmor: Replace two seq_printf() calls by seq_puts() in aa_label_seq_xprint()Markus Elfring2020-01-191-2/+2
| | | | | | | | | | | | | | | | | | | | 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 <elfring@users.sourceforge.net> Signed-off-by: John Johansen <john.johansen@canonical.com>
* | ima: Remove __init annotation from ima_pcrread()Roberto Sassu2020-06-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 6cc7c266e5b4 ("ima: Call ima_calc_boot_aggregate() in ima_eventdigest_init()") added a call to ima_calc_boot_aggregate() so that the digest can be recalculated for the boot_aggregate measurement entry if the 'd' template field has been requested. For the 'd' field, only SHA1 and MD5 digests are accepted. Given that ima_eventdigest_init() does not have the __init annotation, all functions called should not have it. This patch removes __init from ima_pcrread(). Cc: stable@vger.kernel.org Fixes: 6cc7c266e5b4 ("ima: Call ima_calc_boot_aggregate() in ima_eventdigest_init()") Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge tag 'integrity-v5.8' of ↵Linus Torvalds2020-06-0612-87/+390
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull integrity updates from Mimi Zohar: "The main changes are extending the TPM 2.0 PCR banks with bank specific file hashes, calculating the "boot_aggregate" based on other TPM PCR banks, using the default IMA hash algorithm, instead of SHA1, as the basis for the cache hash table key, and preventing the mprotect syscall to circumvent an IMA mmap appraise policy rule. - In preparation for extending TPM 2.0 PCR banks with bank specific digests, commit 0b6cf6b97b7e ("tpm: pass an array of tpm_extend_digest structures to tpm_pcr_extend()") modified tpm_pcr_extend(). The original SHA1 file digests were padded/truncated, before being extended into the other TPM PCR banks. This pull request calculates and extends the TPM PCR banks with bank specific file hashes completing the above change. - The "boot_aggregate", the first IMA measurement list record, is the "trusted boot" link between the pre-boot environment and the running OS. With TPM 2.0, the "boot_aggregate" record is not limited to being based on the SHA1 TPM PCR bank, but can be calculated based on any enabled bank, assuming the hash algorithm is also enabled in the kernel. Other changes include the following and five other bug fixes/code clean up: - supporting both a SHA1 and a larger "boot_aggregate" digest in a custom template format containing both the the SHA1 ('d') and larger digests ('d-ng') fields. - Initial hash table key fix, but additional changes would be good" * tag 'integrity-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: ima: Directly free *entry in ima_alloc_init_template() if digests is NULL ima: Call ima_calc_boot_aggregate() in ima_eventdigest_init() ima: Directly assign the ima_default_policy pointer to ima_rules ima: verify mprotect change is consistent with mmap policy evm: Fix possible memory leak in evm_calc_hmac_or_hash() ima: Set again build_ima_appraise variable ima: Remove redundant policy rule set in add_rules() ima: Fix ima digest hash table key calculation ima: Use ima_hash_algo for collision detection in the measurement list ima: Calculate and extend PCR with digests in ima_template_entry ima: Allocate and initialize tfm for each PCR bank ima: Switch to dynamically allocated buffer for template digests ima: Store template digest directly in ima_template_entry ima: Evaluate error in init_ima() ima: Switch to ima_hash_algo for boot aggregate
| * | ima: Directly free *entry in ima_alloc_init_template() if digests is NULLRoberto Sassu2020-06-051-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To support multiple template digests, the static array entry->digest has been replaced with a dynamically allocated array in commit aa724fe18a8a ("ima: Switch to dynamically allocated buffer for template digests"). The array is allocated in ima_alloc_init_template() and if the returned pointer is NULL, ima_free_template_entry() is called. However, (*entry)->template_desc is not yet initialized while it is used by ima_free_template_entry(). This patch fixes the issue by directly freeing *entry without calling ima_free_template_entry(). Fixes: aa724fe18a8a ("ima: Switch to dynamically allocated buffer for template digests") Reported-by: syzbot+223310b454ba6b75974e@syzkaller.appspotmail.com Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Call ima_calc_boot_aggregate() in ima_eventdigest_init()Roberto Sassu2020-06-034-5/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the template field 'd' is chosen and the digest to be added to the measurement entry was not calculated with SHA1 or MD5, it is recalculated with SHA1, by using the passed file descriptor. However, this cannot be done for boot_aggregate, because there is no file descriptor. This patch adds a call to ima_calc_boot_aggregate() in ima_eventdigest_init(), so that the digest can be recalculated also for the boot_aggregate entry. Cc: stable@vger.kernel.org # 3.13.x Fixes: 3ce1217d6cd5d ("ima: define template fields library and new helpers") Reported-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Directly assign the ima_default_policy pointer to ima_rulesRoberto Sassu2020-06-031-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch prevents the following oops: [ 10.771813] BUG: kernel NULL pointer dereference, address: 0000000000000 [...] [ 10.779790] RIP: 0010:ima_match_policy+0xf7/0xb80 [...] [ 10.798576] Call Trace: [ 10.798993] ? ima_lsm_policy_change+0x2b0/0x2b0 [ 10.799753] ? inode_init_owner+0x1a0/0x1a0 [ 10.800484] ? _raw_spin_lock+0x7a/0xd0 [ 10.801592] ima_must_appraise.part.0+0xb6/0xf0 [ 10.802313] ? ima_fix_xattr.isra.0+0xd0/0xd0 [ 10.803167] ima_must_appraise+0x4f/0x70 [ 10.804004] ima_post_path_mknod+0x2e/0x80 [ 10.804800] do_mknodat+0x396/0x3c0 It occurs when there is a failure during IMA initialization, and ima_init_policy() is not called. IMA hooks still call ima_match_policy() but ima_rules is NULL. This patch prevents the crash by directly assigning the ima_default_policy pointer to ima_rules when ima_rules is defined. This wouldn't alter the existing behavior, as ima_rules is always set at the end of ima_init_policy(). Cc: stable@vger.kernel.org # 3.7.x Fixes: 07f6a79415d7d ("ima: add appraise action keywords and default rules") Reported-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: verify mprotect change is consistent with mmap policyMimi Zohar2020-05-222-1/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Files can be mmap'ed read/write and later changed to execute to circumvent IMA's mmap appraise policy rules. Due to locking issues (mmap semaphore would be taken prior to i_mutex), files can not be measured or appraised at this point. Eliminate this integrity gap, by denying the mprotect PROT_EXECUTE change, if an mmap appraise policy rule exists. On mprotect change success, return 0. On failure, return -EACESS. Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | evm: Fix possible memory leak in evm_calc_hmac_or_hash()Roberto Sassu2020-05-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't immediately return if the signature is portable and security.ima is not present. Just set error so that memory allocated is freed before returning from evm_calc_hmac_or_hash(). Fixes: 50b977481fce9 ("EVM: Add support for portable signature format") Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Set again build_ima_appraise variableKrzysztof Struczynski2020-05-081-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After adding the new add_rule() function in commit c52657d93b05 ("ima: refactor ima_init_policy()"), all appraisal flags are added to the temp_ima_appraise variable. Revert to the previous behavior instead of removing build_ima_appraise, to benefit from the protection offered by __ro_after_init. The mentioned commit introduced a bug, as it makes all the flags modifiable, while build_ima_appraise flags can be protected with __ro_after_init. Cc: stable@vger.kernel.org # 5.0.x Fixes: c52657d93b05 ("ima: refactor ima_init_policy()") Co-developed-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Remove redundant policy rule set in add_rules()Krzysztof Struczynski2020-05-081-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | Function ima_appraise_flag() returns the flag to be set in temp_ima_appraise depending on the hook identifier passed as an argument. It is not necessary to set the flag again for the POLICY_CHECK hook. Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Fix ima digest hash table key calculationKrzysztof Struczynski2020-05-081-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Function hash_long() accepts unsigned long, while currently only one byte is passed from ima_hash_key(), which calculates a key for ima_htable. Given that hashing the digest does not give clear benefits compared to using the digest itself, remove hash_long() and return the modulus calculated on the first two bytes of the digest with the number of slots. Also reduce the depth of the hash table by doubling the number of slots. Cc: stable@vger.kernel.org Fixes: 3323eec921ef ("integrity: IMA as an integrity service provider") Co-developed-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com> Acked-by: David.Laight@aculab.com (big endian system concerns) Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Use ima_hash_algo for collision detection in the measurement listRoberto Sassu2020-04-203-5/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before calculating a digest for each PCR bank, collisions were detected with a SHA1 digest. This patch includes ima_hash_algo among the algorithms used to calculate the template digest and checks collisions on that digest. The position in the measurement entry array of the template digest calculated with the IMA default hash algorithm is stored in the ima_hash_algo_idx global variable and is determined at IMA initialization time. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Calculate and extend PCR with digests in ima_template_entryRoberto Sassu2020-04-203-15/+58
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch modifies ima_calc_field_array_hash() to calculate a template digest for each allocated PCR bank and SHA1. It also passes the tpm_digest array of the template entry to ima_pcr_extend() or in case of a violation, the pre-initialized digests array filled with 0xff. Padding with zeros is still done if the mapping between TPM algorithm ID and crypto ID is unknown. This patch calculates again the template digest when a measurement list is restored. Copying only the SHA1 digest (due to the limitation of the current measurement list format) is not sufficient, as hash collision detection will be done on the digest calculated with the IMA default hash algorithm. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Allocate and initialize tfm for each PCR bankRoberto Sassu2020-04-201-26/+119
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch creates a crypto_shash structure for each allocated PCR bank and for SHA1 if a bank with that algorithm is not currently allocated. Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Switch to dynamically allocated buffer for template digestsRoberto Sassu2020-04-206-10/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch dynamically allocates the array of tpm_digest structures in ima_alloc_init_template() and ima_restore_template_data(). The size of the array is equal to the number of PCR banks plus ima_extra_slots, to make room for SHA1 and the IMA default hash algorithm, when PCR banks with those algorithms are not allocated. Calculating the SHA1 digest is mandatory, as SHA1 still remains the default hash algorithm for the measurement list. When IMA will support the Crypto Agile format, remaining digests will be also provided. The position in the measurement entry array of the SHA1 digest is stored in the ima_sha1_idx global variable and is determined at IMA initialization time. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Store template digest directly in ima_template_entryRoberto Sassu2020-04-203-24/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In preparation for the patch that calculates a digest for each allocated PCR bank, this patch passes to ima_calc_field_array_hash() the ima_template_entry structure, so that digests can be directly stored in that structure instead of ima_digest_data. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Evaluate error in init_ima()Roberto Sassu2020-04-201-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Evaluate error in init_ima() before register_blocking_lsm_notifier() and return if not zero. Cc: stable@vger.kernel.org # 5.3.x Fixes: b16942455193 ("ima: use the lsm policy update notifier") Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * | ima: Switch to ima_hash_algo for boot aggregateRoberto Sassu2020-04-202-11/+58
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | boot_aggregate is the first entry of IMA measurement list. Its purpose is to link pre-boot measurements to IMA measurements. As IMA was designed to work with a TPM 1.2, the SHA1 PCR bank was always selected even if a TPM 2.0 with support for stronger hash algorithms is available. This patch first tries to find a PCR bank with the IMA default hash algorithm. If it does not find it, it selects the SHA256 PCR bank for TPM 2.0 and SHA1 for TPM 1.2. Ultimately, it selects SHA1 also for TPM 2.0 if the SHA256 PCR bank is not found. If none of the PCR banks above can be found, boot_aggregate file digest is filled with zeros, as for TPM bypass, making it impossible to perform a remote attestation of the system. Cc: stable@vger.kernel.org # 5.1.x Fixes: 879b589210a9 ("tpm: retrieve digest size of unknown algorithms with PCR read") Reported-by: Jerry Snitselaar <jsnitsel@redhat.com> Suggested-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* | | Merge branch 'akpm' (patches from Andrew)Linus Torvalds2020-06-052-22/+5
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge yet more updates from Andrew Morton: - More MM work. 100ish more to go. Mike Rapoport's "mm: remove __ARCH_HAS_5LEVEL_HACK" series should fix the current ppc issue - Various other little subsystems * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (127 commits) lib/ubsan.c: fix gcc-10 warnings tools/testing/selftests/vm: remove duplicate headers selftests: vm: pkeys: fix multilib builds for x86 selftests: vm: pkeys: use the correct page size on powerpc selftests/vm/pkeys: override access right definitions on powerpc selftests/vm/pkeys: test correct behaviour of pkey-0 selftests/vm/pkeys: introduce a sub-page allocator selftests/vm/pkeys: detect write violation on a mapped access-denied-key page selftests/vm/pkeys: associate key on a mapped page and detect write violation selftests/vm/pkeys: associate key on a mapped page and detect access violation selftests/vm/pkeys: improve checks to determine pkey support selftests/vm/pkeys: fix assertion in test_pkey_alloc_exhaust() selftests/vm/pkeys: fix number of reserved powerpc pkeys selftests/vm/pkeys: introduce powerpc support selftests/vm/pkeys: introduce generic pkey abstractions selftests: vm: pkeys: use the correct huge page size selftests/vm/pkeys: fix alloc_random_pkey() to make it really random selftests/vm/pkeys: fix assertion in pkey_disable_set/clear() selftests/vm/pkeys: fix pkey_disable_clear() selftests: vm: pkeys: add helpers for pkey bits ...
| * | | mm: add kvfree_sensitive() for freeing sensitive data objectsWaiman Long2020-06-052-22/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For kvmalloc'ed data object that contains sensitive information like cryptographic keys, we need to make sure that the buffer is always cleared before freeing it. Using memset() alone for buffer clearing may not provide certainty as the compiler may compile it away. To be sure, the special memzero_explicit() has to be used. This patch introduces a new kvfree_sensitive() for freeing those sensitive data objects allocated by kvmalloc(). The relevant places where kvfree_sensitive() can be used are modified to use it. Fixes: 4f0882491a14 ("KEYS: Avoid false positive ENOMEM error on key read") Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Eric Biggers <ebiggers@google.com> Acked-by: David Howells <dhowells@redhat.com> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Uladzislau Rezki <urezki@gmail.com> Link: http://lkml.kernel.org/r/20200407200318.11711-1-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | Merge branch 'exec-linus' of ↵Linus Torvalds2020-06-048-40/+32
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 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://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (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 ...
| * | | | exec: Compute file based creds only onceEric W. Biederman2020-05-302-13/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the computation of creds from prepare_binfmt into begin_new_exec so that the creds need only be computed once. This is just code reorganization no semantic changes of any kind are made. Moving the computation is safe. I have looked through the kernel and verified none of the binfmts look at bprm->cred directly, and that there are no helpers that look at bprm->cred indirectly. Which means that it is not a problem to compute the bprm->cred later in the execution flow as it is not used until it becomes current->cred. A new function bprm_creds_from_file is added to contain the work that needs to be done. bprm_creds_from_file first computes which file bprm->executable or most likely bprm->file that the bprm->creds will be computed from. The funciton bprm_fill_uid is updated to receive the file instead of accessing bprm->file. The now unnecessary work needed to reset the bprm->cred->euid, and bprm->cred->egid is removed from brpm_fill_uid. A small comment to document that bprm_fill_uid now only deals with the work to handle suid and sgid files. The default case is already heandled by prepare_exec_creds. The function security_bprm_repopulate_creds is renamed security_bprm_creds_from_file and now is explicitly passed the file from which to compute the creds. The documentation of the bprm_creds_from_file security hook is updated to explain when the hook is called and what it needs to do. The file is passed from cap_bprm_creds_from_file into get_file_caps so that the caps are computed for the appropriate file. The now unnecessary work in cap_bprm_creds_from_file to reset the ambient capabilites has been removed. A small comment to document that the work of cap_bprm_creds_from_file is to read capabilities from the files secureity attribute and derive capabilities from the fact the user had uid 0 has been added. Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
| * | | | exec: Add a per bprm->file version of per_clearEric W. Biederman2020-05-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a small bug in the code that recomputes parts of bprm->cred for every bprm->file. The code never recomputes the part of clear_dangerous_personality_flags it is responsible for. Which means that in practice if someone creates a sgid script the interpreter will not be able to use any of: READ_IMPLIES_EXEC ADDR_NO_RANDOMIZE ADDR_COMPAT_LAYOUT MMAP_PAGE_ZERO. This accentially clearing of personality flags probably does not matter in practice because no one has complained but it does make the code more difficult to understand. Further remaining bug compatible prevents the recomputation from being removed and replaced by simply computing bprm->cred once from the final bprm->file. Making this change removes the last behavior difference between computing bprm->creds from the final file and recomputing bprm->cred several times. Which allows this behavior change to be justified for it's own reasons, and for any but hunts looking into why the behavior changed to wind up here instead of in the code that will follow that computes bprm->cred from the final bprm->file. This small logic bug appears to have existed since the code started clearing dangerous personality bits. History Tree: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Fixes: 1bb0fa189c6a ("[PATCH] NX: clean up legacy binary support") Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
| * | | | Merge commit a4ae32c71fe9 ("exec: Always set cap_ambient in cap_bprm_set_creds")Eric W. Biederman2020-05-281-0/+1
| |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a bug fix and one of two places where I have found that the result of calling security_bprm_repopulate_creds more than once on different bprm->files depends on all of the bprm->files not just the file bprm->file. I intend to fix both of those cases and then modify the code to only call security_bprm_repopulate_creds on the final bprm file. So merge this change in so I hopefully reduce conflicts for others and I make it possible to build on top of this change. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
| * | | | | exec: Convert security_bprm_set_creds into security_bprm_repopulate_credsEric W. Biederman2020-05-212-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename bprm->cap_elevated to bprm->active_secureexec and initialize it in prepare_binprm instead of in cap_bprm_set_creds. Initializing bprm->active_secureexec in prepare_binprm allows multiple implementations of security_bprm_repopulate_creds to play nicely with each other. Rename security_bprm_set_creds to security_bprm_reopulate_creds to emphasize that this path recomputes part of bprm->cred. This recomputation avoids the time of check vs time of use problems that are inherent in unix #! interpreters. In short two renames and a move in the location of initializing bprm->active_secureexec. Link: https://lkml.kernel.org/r/87o8qkzrxp.fsf_-_@x220.int.ebiederm.org Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
| * | | | | exec: Factor security_bprm_creds_for_exec out of security_bprm_set_credsEric W. Biederman2020-05-207-27/+18
| | |_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: https://lkml.kernel.org/r/87v9kszrzh.fsf_-_@x220.int.ebiederm.org Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Casey Schaufler <casey@schaufler-ca.com> # For the LSM and Smack bits Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | | | | Merge branch 'proc-linus' of ↵Linus Torvalds2020-06-041-1/+3
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull proc updates from Eric Biederman: "This has four sets of changes: - modernize proc to support multiple private instances - ensure we see the exit of each process tid exactly - remove has_group_leader_pid - use pids not tasks in posix-cpu-timers lookup Alexey updated proc so each mount of proc uses a new superblock. This allows people to actually use mount options with proc with no fear of messing up another mount of proc. Given the kernel's internal mounts of proc for things like uml this was a real problem, and resulted in Android's hidepid mount options being ignored and introducing security issues. The rest of the changes are small cleanups and fixes that came out of my work to allow this change to proc. In essence it is swapping the pids in de_thread during exec which removes a special case the code had to handle. Then updating the code to stop handling that special case" * 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: proc: proc_pid_ns takes super_block as an argument remove the no longer needed pid_alive() check in __task_pid_nr_ns() posix-cpu-timers: Replace __get_task_for_clock with pid_for_clock posix-cpu-timers: Replace cpu_timer_pid_type with clock_pid_type posix-cpu-timers: Extend rcu_read_lock removing task_struct references signal: Remove has_group_leader_pid exec: Remove BUG_ON(has_group_leader_pid) posix-cpu-timer: Unify the now redundant code in lookup_task posix-cpu-timer: Tidy up group_leader logic in lookup_task proc: Ensure we see the exit of each process tid exactly once rculist: Add hlists_swap_heads_rcu proc: Use PIDTYPE_TGID in next_tgid Use proc_pid_ns() to get pid_namespace from the proc superblock proc: use named enums for better readability proc: use human-readable values for hidepid docs: proc: add documentation for "hidepid=4" and "subset=pid" options and new mount behavior proc: add option to mount only a pids subset proc: instantiate only pids that we can ptrace on 'hidepid=4' mount option proc: allow to mount many instances of proc in one pid namespace proc: rename struct proc_fs_info to proc_fs_opts
| * | | | | proc: proc_pid_ns takes super_block as an argumentAlexey Gladkov2020-05-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | syzbot found that touch /proc/testfile causes NULL pointer dereference at tomoyo_get_local_path() because inode of the dentry is NULL. Before c59f415a7cb6, Tomoyo received pid_ns from proc's s_fs_info directly. Since proc_pid_ns() can only work with inode, using it in the tomoyo_get_local_path() was wrong. To avoid creating more functions for getting proc_ns, change the argument type of the proc_pid_ns() function. Then, Tomoyo can use the existing super_block to get pid_ns. Link: https://lkml.kernel.org/r/0000000000002f0c7505a5b0e04c@google.com Link: https://lkml.kernel.org/r/20200518180738.2939611-1-gladkov.alexey@gmail.com Reported-by: syzbot+c1af344512918c61362c@syzkaller.appspotmail.com Fixes: c59f415a7cb6 ("Use proc_pid_ns() to get pid_namespace from the proc superblock") Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
| * | | | | Use proc_pid_ns() to get pid_namespace from the proc superblockAlexey Gladkov2020-04-241-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To get pid_namespace from the procfs superblock should be used a special helper. This will avoid errors when s_fs_info will change the type. Link: https://lore.kernel.org/lkml/20200423200316.164518-3-gladkov.alexey@gmail.com/ Link: https://lore.kernel.org/lkml/20200423112858.95820-1-gladkov.alexey@gmail.com/ Link: https://lore.kernel.org/lkml/06B50A1C-406F-4057-BFA8-3A7729EA7469@lca.pw/ Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* | | | | | Merge tag 'Smack-for-5.8' of git://github.com/cschaufler/smack-nextLinus Torvalds2020-06-043-43/+21
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull smack updates from Casey Schaufler: "Clean out dead code and repair an out-of-bounds warning" * tag 'Smack-for-5.8' of git://github.com/cschaufler/smack-next: Smack: Remove unused inline function smk_ad_setfield_u_fs_path_mnt Smack:- Remove redundant inode_smack cache Smack:- Remove mutex lock "smk_lock" from inode_smack Smack: slab-out-of-bounds in vsscanf smack: remove redundant structure variable from header. smack: avoid unused 'sip' variable warning
| * | | | | | Smack: Remove unused inline function smk_ad_setfield_u_fs_path_mntYueHaibing2020-05-111-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit a269434d2fb4 ("LSM: separate LSM_AUDIT_DATA_DENTRY from LSM_AUDIT_DATA_PATH") left behind this, remove it. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| * | | | | | Smack:- Remove redundant inode_smack cacheCasey Schaufler2020-05-061-8/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The inode_smack cache is no longer used. Remove it. Signed-off-by: Vishal Goel <vishal.goel@samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| * | | | | | Smack:- Remove mutex lock "smk_lock" from inode_smackCasey Schaufler2020-05-062-7/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | "smk_lock" mutex is used during inode instantiation in smack_d_instantiate()function. It has been used to avoid simultaneous access on same inode security structure. Since smack related initialization is done only once i.e during inode creation. If the inode has already been instantiated then smack_d_instantiate() function just returns without doing anything. So it means mutex lock is required only during inode creation. But since 2 processes can't create same inodes or files simultaneously. Also linking or some other file operation can't be done simultaneously when the file is getting created since file lookup will fail before dentry inode linkup which is done after smack initialization. So no mutex lock is required in inode_smack structure. It will save memory as well as improve some performance. If 40000 inodes are created in system, it will save 1.5 MB on 32-bit systems & 2.8 MB on 64-bit systems. Signed-off-by: Vishal Goel <vishal.goel@samsung.com> Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
| * | | | | | Smack: slab-out-of-bounds in vsscanfCasey Schaufler2020-05-061-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add barrier to soob. Return -EOVERFLOW if the buffer is exceeded. Suggested-by: Hillf Danton <hdanton@sina.com> Reported-by: syzbot+bfdd4a2f07be52351350@syzkaller.appspotmail.com Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>