linux/security/smack, branch v4.0

Smack: Use d_is_positive() rather than testing dentry->d_inode

2015-02-22T16:38:40Z

Use d_is_positive() rather than testing dentry->d_inode in Smack to get rid of direct references to d_inode outside of the VFS. Signed-off-by: David Howells Signed-off-by: Al Viro

Smack: secmark connections

2015-02-11T20:55:05Z

If the secmark is available us it on connection as well as packet delivery. Signed-off-by: Casey Schaufler

Smack: Repair netfilter dependency

2015-01-23T18:08:19Z

On 1/23/2015 8:20 AM, Jim Davis wrote: > Building with the attached random configuration file, > > security/smack/smack_netfilter.c: In function ‘smack_ipv4_output’: > security/smack/smack_netfilter.c:55:6: error: ‘struct sk_buff’ has no > member named ‘secmark’ > skb->secmark = skp->smk_secid; > ^ > make[2]: *** [security/smack/smack_netfilter.o] Error 1 The existing Makefile used the wrong configuration option to determine if smack_netfilter should be built. This sets it right. Signed-off-by: Casey Schaufler

smack: fix possible use after frees in task_security() callers

2015-01-21T19:56:53Z

We hit use after free on dereferncing pointer to task_smack struct in smk_of_task() called from smack_task_to_inode(). task_security() macro uses task_cred_xxx() to get pointer to the task_smack. task_cred_xxx() could be used only for non-pointer members of task's credentials. It cannot be used for pointer members since what they point to may disapper after dropping RCU read lock. Mainly task_security() used this way: smk_of_task(task_security(p)) Intead of this introduce function smk_of_task_struct() which takes task_struct as argument and returns pointer to smk_known struct and do this under RCU read lock. Bogus task_security() macro is not used anymore, so remove it. KASan's report for this: AddressSanitizer: use after free in smack_task_to_inode+0x50/0x70 at addr c4635600 ============================================================================= BUG kmalloc-64 (Tainted: PO): kasan error ----------------------------------------------------------------------------- Disabling lock debugging due to kernel taint INFO: Allocated in new_task_smack+0x44/0xd8 age=39 cpu=0 pid=1866 kmem_cache_alloc_trace+0x88/0x1bc new_task_smack+0x44/0xd8 smack_cred_prepare+0x48/0x21c security_prepare_creds+0x44/0x4c prepare_creds+0xdc/0x110 smack_setprocattr+0x104/0x150 security_setprocattr+0x4c/0x54 proc_pid_attr_write+0x12c/0x194 vfs_write+0x1b0/0x370 SyS_write+0x5c/0x94 ret_fast_syscall+0x0/0x48 INFO: Freed in smack_cred_free+0xc4/0xd0 age=27 cpu=0 pid=1564 kfree+0x270/0x290 smack_cred_free+0xc4/0xd0 security_cred_free+0x34/0x3c put_cred_rcu+0x58/0xcc rcu_process_callbacks+0x738/0x998 __do_softirq+0x264/0x4cc do_softirq+0x94/0xf4 irq_exit+0xbc/0x120 handle_IRQ+0x104/0x134 gic_handle_irq+0x70/0xac __irq_svc+0x44/0x78 _raw_spin_unlock+0x18/0x48 sync_inodes_sb+0x17c/0x1d8 sync_filesystem+0xac/0xfc vdfs_file_fsync+0x90/0xc0 vfs_fsync_range+0x74/0x7c INFO: Slab 0xd3b23f50 objects=32 used=31 fp=0xc4635600 flags=0x4080 INFO: Object 0xc4635600 @offset=5632 fp=0x (null) Bytes b4 c46355f0: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ Object c4635600: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object c4635610: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object c4635620: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object c4635630: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 kkkkkkkkkkkkkkk. Redzone c4635640: bb bb bb bb .... Padding c46356e8: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ Padding c46356f8: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ CPU: 5 PID: 834 Comm: launchpad_prelo Tainted: PBO 3.10.30 #1 Backtrace: [] (dump_backtrace+0x0/0x158) from [] (show_stack+0x20/0x24) r7:c4634010 r6:d3b23f50 r5:c4635600 r4:d1002140 [] (show_stack+0x0/0x24) from [] (dump_stack+0x20/0x28) [] (dump_stack+0x0/0x28) from [] (print_trailer+0x124/0x144) [] (print_trailer+0x0/0x144) from [] (object_err+0x3c/0x44) r7:c4635600 r6:d1002140 r5:d3b23f50 r4:c4635600 [] (object_err+0x0/0x44) from [] (kasan_report_error+0x2b8/0x538) r6:d1002140 r5:d3b23f50 r4:c6429cf8 r3:c09e1aa7 [] (kasan_report_error+0x0/0x538) from [] (__asan_load4+0xd4/0xf8) [] (__asan_load4+0x0/0xf8) from [] (smack_task_to_inode+0x50/0x70) r5:c4635600 r4:ca9da000 [] (smack_task_to_inode+0x0/0x70) from [] (security_task_to_inode+0x3c/0x44) r5:cca25e80 r4:c0ba9780 [] (security_task_to_inode+0x0/0x44) from [] (pid_revalidate+0x124/0x178) r6:00000000 r5:cca25e80 r4:cbabe3c0 r3:00008124 [] (pid_revalidate+0x0/0x178) from [] (lookup_fast+0x35c/0x43y4) r9:c6429efc r8:00000101 r7:c079d940 r6:c6429e90 r5:c6429ed8 r4:c83c4148 [] (lookup_fast+0x0/0x434) from [] (do_last.isra.24+0x1c0/0x1108) [] (do_last.isra.24+0x0/0x1108) from [] (path_openat.isra.25+0xf4/0x648) [] (path_openat.isra.25+0x0/0x648) from [] (do_filp_open+0x3c/0x88) [] (do_filp_open+0x0/0x88) from [] (do_sys_open+0xf0/0x198) r7:00000001 r6:c0ea2180 r5:0000000b r4:00000000 [] (do_sys_open+0x0/0x198) from [] (SyS_open+0x30/0x34) [] (SyS_open+0x0/0x34) from [] (ret_fast_syscall+0x0/0x48) Read of size 4 by thread T834: Memory state around the buggy address: c4635380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc c4635400: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc c4635480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc c4635500: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc c4635580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >c4635600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ c4635680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb c4635700: 00 00 00 00 04 fc fc fc fc fc fc fc fc fc fc fc c4635780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc c4635800: 00 00 00 00 00 00 04 fc fc fc fc fc fc fc fc fc c4635880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== Signed-off-by: Andrey Ryabinin Cc:

smack: Add missing logging in bidirectional UDS connect check

2015-01-21T00:35:31Z

During UDS connection check, both sides are checked for write access to the other side. But only the first check is performed with audit support. The second one didn't produce any audit logs. This simple patch fixes that. Signed-off-by: Rafal Krypa

Smack: secmark support for netfilter

2015-01-21T00:34:25Z

Smack uses CIPSO to label internet packets and thus provide for access control on delivery of packets. The netfilter facility was not used to allow for Smack to work properly without netfilter configuration. Smack does not need netfilter, however there are cases where it would be handy. As a side effect, the labeling of local IPv4 packets can be optimized and the handling of local IPv6 packets is just all out better. The best part is that the netfilter tools use "contexts" that are just strings, and they work just as well for Smack as they do for SELinux. All of the conditional compilation for IPv6 was implemented by Rafal Krypa Signed-off-by: Casey Schaufler

Smack: Rework file hooks

2015-01-21T00:32:17Z

This is one of those cases where you look at code you did years ago and wonder what you might have been thinking. There are a number of LSM hooks that work off of file pointers, and most of them really want the security data from the inode. Some, however, really want the security context that the process had when the file was opened. The difference went undetected in Smack until it started getting used in a real system with real testing. At that point it was clear that something was amiss. This patch corrects the misuse of the f_security value in several of the hooks. The behavior will not usually be any different, as the process had to be able to open the file in the first place, and the old check almost always succeeded, as will the new, but for different reasons. Thanks to the Samsung Tizen development team that identified this. Signed-off-by: Casey Schaufler

smack: Fix a bidirectional UDS connect check typo

2015-01-19T18:00:05Z

The 54e70ec5eb090193b03e69d551fa6771a5a217c4 commit introduced a bidirectional check that should have checked for mutual WRITE access between two labels. Due to a typo subject's OUT label is checked with object's OUT. Should be OUT to IN. Signed-off-by: Zbigniew Jasinski

smack: introduce a special case for tmpfs in smack_d_instantiate()

2015-01-19T17:58:02Z

Files created with __shmem_file_stup() appear to have somewhat fake dentries which make them look like root directories and not get the label the current process or ("*") star meant for tmpfs files. Signed-off-by: Łukasz Stelmach

smack: fix logic in smack_inode_init_security function

2015-01-19T17:18:11Z

In principle if this function was called with "value" == NULL and "len" not NULL it could return different results for the "len" compared to a case where "name" was not NULL. This is a hypothetical case that does not exist in the kernel, but it's a logic bug nonetheless. Signed-off-by: Lukasz Pawelczyk