From 4a856adf28238ec7d4b0b990ae886c64fd4a7090 Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Wed, 21 Feb 2018 04:30:07 -0500 Subject: [PATCH] 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 --- kernel/audit.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/audit.c b/kernel/audit.c index 5b34d3114af4..d301276bca58 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -1058,6 +1058,8 @@ 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,