From: Richard Guy Briggs Date: Wed, 21 Feb 2018 09:30:07 +0000 (-0500) Subject: audit: return on memory error to avoid null pointer dereference X-Git-Tag: v4.9.104~16 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=85e924bb3309d59ffee2e0c23c920c74826ba509;p=thirdparty%2Fkernel%2Fstable.git audit: return on memory error to avoid null pointer dereference [ Upstream commit 23138ead270045f1b3e912e667967b6094244999 ] If there is a memory allocation error when trying to change an audit kernel feature value, the ignored allocation error will trigger a NULL pointer dereference oops on subsequent use of that pointer. Return instead. Passes audit-testsuite. See: https://github.com/linux-audit/audit-kernel/issues/76 Signed-off-by: Richard Guy Briggs [PM: not necessary (other funcs check for NULL), but a good practice] Signed-off-by: Paul Moore Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- diff --git a/kernel/audit.c b/kernel/audit.c index da4e7c0e36f7a..3461a3d874fed 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -742,6 +742,8 @@ static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature return; ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_FEATURE_CHANGE); + if (!ab) + return; audit_log_task_info(ab, current); audit_log_format(ab, " feature=%s old=%u new=%u old_lock=%u new_lock=%u res=%d", audit_feature_names[which], !!old_feature, !!new_feature,