linux-dev/security/selinux/ss/services.c, branch linus/master

selinux: declare data arrays const

2022-05-03T19:53:49Z

The arrays for the policy capability names, the initial sid identifiers and the class and permission names are not changed at runtime. Declare them const to avoid accidental modification. Do not override the classmap and the initial sid list in the build time script genheaders. Check flose(3) is successful in genheaders.c, otherwise the written data might be corrupted or incomplete. Signed-off-by: Christian Göttsche [PM: manual merge due to fuzz, minor style tweaks] Signed-off-by: Paul Moore

selinux: fix indentation level of mls_ops block

2022-05-03T18:26:53Z

Add one level of indentation to the code block of the label mls_ops in constraint_expr_eval(), to adjust the trailing break; to the parent case: branch. Signed-off-by: Christian Göttsche Signed-off-by: Paul Moore

selinux: Remove redundant assignments

2022-04-04T19:38:53Z

Get rid of redundant assignments which end up in values not being read either because they are overwritten or the function ends. Reported by clang-tidy [deadcode.DeadStores] Signed-off-by: Michal Orzel Signed-off-by: Paul Moore

selinux: drop return statement at end of void functions

2022-02-18T15:42:12Z

Those return statements at the end of a void function are redundant. Reported by clang-tidy [readability-redundant-control-flow] Signed-off-by: Christian Göttsche Signed-off-by: Paul Moore

selinux: drop cast to same type

2022-01-26T20:25:47Z

Both the lvalue scontextp and rvalue scontext are of the type char*. Drop the redundant explicit cast not needed since commit 9a59daa03df7 ("SELinux: fix sleeping allocation in security_context_to_sid"), where the type of scontext changed from const char* to char*. Signed-off-by: Christian Göttsche Signed-off-by: Paul Moore

selinux: declare path parameters of _genfs_sid const

2022-01-26T00:59:52Z

The path parameter is only read from in security_genfs_sid(), selinux_policy_genfs_sid() and __security_genfs_sid(). Since a string literal is passed as argument, declare the parameter const. Also align the parameter names in the declaration and definition. Reported by clang [-Wwrite-strings]: security/selinux/hooks.c:553:60: error: passing 'const char [2]' to parameter of type 'char *' discards qualifiers [-Wincompatible-pointer-types-discards-qualifiers] rc = security_genfs_sid(&selinux_state, ... , /, ^~~ ./security/selinux/include/security.h:389:36: note: passing argument to parameter 'name' here const char *fstype, char *name, u16 sclass, ^ Signed-off-by: Christian Göttsche [PM: wrapped description] Signed-off-by: Paul Moore

selinux: fix all of the W=1 build warnings

2021-10-13T20:31:51Z

There were a number of places in the code where the function definition did not match the associated comment block as well at least one file where the appropriate header files were not included (missing function declaration/prototype); this patch fixes all of these issue such that building the SELinux code with "W=1" is now warning free. % make W=1 security/selinux/ Signed-off-by: Paul Moore

selinux: fix race condition when computing ocontext SIDs

2021-10-11T23:18:04Z

Current code contains a lot of racy patterns when converting an ocontext's context structure to an SID. This is being done in a "lazy" fashion, such that the SID is looked up in the SID table only when it's first needed and then cached in the "sid" field of the ocontext structure. However, this is done without any locking or memory barriers and is thus unsafe. Between commits 24ed7fdae669 ("selinux: use separate table for initial SID lookup") and 66f8e2f03c02 ("selinux: sidtab reverse lookup hash table"), this race condition lead to an actual observable bug, because a pointer to the shared sid field was passed directly to sidtab_context_to_sid(), which was using this location to also store an intermediate value, which could have been read by other threads and interpreted as an SID. In practice this caused e.g. new mounts to get a wrong (seemingly random) filesystem context, leading to strange denials. This bug has been spotted in the wild at least twice, see [1] and [2]. Fix the race condition by making all the racy functions use a common helper that ensures the ocontext::sid accesses are made safely using the appropriate SMP constructs. Note that security_netif_sid() was populating the sid field of both contexts stored in the ocontext, but only the first one was actually used. The SELinux wiki's documentation on the "netifcon" policy statement [3] suggests that using only the first context is intentional. I kept only the handling of the first context here, as there is really no point in doing the SID lookup for the unused one. I wasn't able to reproduce the bug mentioned above on any kernel that includes commit 66f8e2f03c02, even though it has been reported that the issue occurs with that commit, too, just less frequently. Thus, I wasn't able to verify that this patch fixes the issue, but it makes sense to avoid the race condition regardless. [1] https://github.com/containers/container-selinux/issues/89 [2] https://lists.fedoraproject.org/archives/list/selinux@lists.fedoraproject.org/thread/6DMTAMHIOAOEMUAVTULJD45JZU7IBAFM/ [3] https://selinuxproject.org/page/NetworkStatements#netifcon Cc: stable@vger.kernel.org Cc: Xinjie Zheng Reported-by: Sujithra Periasamy Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Ondrej Mosnacek Signed-off-by: Paul Moore

selinux: return early for possible NULL audit buffers

2021-07-14T19:25:27Z

audit_log_start() may return NULL in below cases: - when audit is not initialized. - when audit backlog limit exceeds. After the call to audit_log_start() is made and then possible NULL audit buffer argument is passed to audit_log_*() functions, audit_log_*() functions return immediately in case of a NULL audit buffer argument. But it is optimal to return early when audit_log_start() returns NULL, because it is not necessary for audit_log_*() functions to be called with NULL audit buffer argument. So add exception handling for possible NULL audit buffers where return value can be handled from callers. Signed-off-by: Austin Kim [PM: tweak subject line] Signed-off-by: Paul Moore

selinux: Fix kernel-doc

2021-06-11T16:59:45Z

Fix function name and add comment for parameter state in ss/services.c kernel-doc to remove some warnings found by running make W=1 LLVM=1. Reported-by: Abaci Robot Signed-off-by: Yang Li Signed-off-by: Paul Moore