From 893c47d1964f5c9b00c5468f2cd1a1e9351fbb6a Mon Sep 17 00:00:00 2001 From: Austin Kim Date: Wed, 14 Jul 2021 01:11:27 +0100 Subject: selinux: return early for possible NULL audit buffers 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 --- security/selinux/hooks.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index b0032c42333e..9e84e6635f2f 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3325,6 +3325,8 @@ static int selinux_inode_setxattr(struct user_namespace *mnt_userns, } ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR); + if (!ab) + return rc; audit_log_format(ab, "op=setxattr invalid_context="); audit_log_n_untrustedstring(ab, value, audit_size); audit_log_end(ab); @@ -6552,6 +6554,8 @@ static int selinux_setprocattr(const char *name, void *value, size_t size) ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR); + if (!ab) + return error; audit_log_format(ab, "op=fscreate invalid_context="); audit_log_n_untrustedstring(ab, value, audit_size); audit_log_end(ab); -- cgit v1.2.3