From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f179.google.com (mail-pf1-f179.google.com [209.85.210.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D50FC2ECD0F for ; Tue, 21 Oct 2025 08:08:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.179 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761034141; cv=none; b=cdVpIWjpeQq0bQGDj2yjRtkUhlQYZLlgBHxc2LGRcl/K1ARzQcec7TvXvN9+ffXlMv9/q4AkTIrbi9+W8ui2xI78TTjZNn1FGzKbRuvUqsHi1LJsjZv4FtQuKI3SxVzdmP01sR59uU5SnYlyWQzT3LFvi/WIwHZMy3knfSQIZhY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761034141; c=relaxed/simple; bh=FwP7RFhS/UAFSpDkb3KLcxGDte+je8FgtPNCjZxV0Ug=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=JcAE7NbFm3eBOEoqgk143Y+fJV5V4HaXj8/l/7iv1EGQIPoXrTQb/eKYSqfHa/CK2XXYotN6gDpzoPAd82SpzlNpoS35lWlAhjblWU5rcSO0W8qxEvFxg2rJpxqplXYfwbC7pXz42elaI7LgSvb6IZMZCfAb/DYxzVHFx1pkTL4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=LUs+4XVI; arc=none smtp.client-ip=209.85.210.179 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LUs+4XVI" Received: by mail-pf1-f179.google.com with SMTP id d2e1a72fcca58-781251eec51so4153235b3a.3 for ; Tue, 21 Oct 2025 01:08:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1761034139; x=1761638939; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=d6omVxeHPJccVZYxmUB5z3Y6O20DnvuzVWmKGSg10CY=; b=LUs+4XVI/m6aO9YGTf8f9xtrCYHO76qDYeUU96tPMVv1rJ/43XfmPhZ7QMP25iNse2 0vwPUpx+F6YeXV0BuQPvarhspEtyopdT/zv+cTE87csDc7SRPn6B1voNAmQLM99a7lC/ DvQTKEPj0DBVedrI39Z2mz29hKwV0an0ucp9/wy2bvsBbRxOtW+H7VlLW//rCFrU+CPB 8fSwb8onz2pMqpdkkcja/RhCBgnf2Y73IR5AKAP6lu7e70l6THrmiOOpW3Z1xUkPu/3X cnf45MjxXg6+NMDdz4cJiH1uoAX2VtW2vESye3s+Q8SxIW89/1BKw6LPjW2DwP+mD313 bGaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1761034139; x=1761638939; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=d6omVxeHPJccVZYxmUB5z3Y6O20DnvuzVWmKGSg10CY=; b=sjFNSp3SEaRW2ELa74R60cPyx7E11RpntedHCjIPk4gRACGwVYshh80T5ELMos8tYm yLoYC24S13jv3rNRZXpPe3viMvBfop1fjKX5EZKL/2g72G6+BPFMVU/YEdPyiZDYMrEx kX5kNr35kWjPNVCwyOSBUBhsD78IXSZ8MSBZcLCx7T4StBVn763RIWlZYEXZShWo+gFL cvMM8FafmKYh7VeAs3zUZjhQepsTjgW1Wn9LQmOXJfm+x9ZhL6JYi8tcMI0VrfKkthtP hnLZx+42n99x3ELiFsG+YJYVB4nyP8O+SU4v6X8JXo1d2IyZlt7TNRS9d9byXI0+i+cw el/A== X-Gm-Message-State: AOJu0YxHbo6q148+rfcPCB7w/SW/DROIXnIvwbOKOTvYdwvUlbYIpjD5 92BRnH69yCdGViU8bwu6SVWA9V4D3KfvqtNoFOaCSH5fvCmL1KWZG2QI2H98FMfN X-Gm-Gg: ASbGncvZhYx5IRidbAElBDi4I7y1OTGdG87jKx7xlW3I/44aY6LfILndrGDQT55ypMO FihkOh2n0rySvlLDNocimiLxIFCDCdGBYJy3wMrY99ApvI1sEBL2S3iyS4SRSMtRNvJWaZnvGBQ sXQ/vEVn3V2D7fNAzdibFaSnKNOKPNklXC50wNOqR56SGED/Zahnupnbu9wMrzvX/wq+RaDzjWw 5J6CH4NtfyeIH+i17X+uCFzXaXKEg44gRS+2mNhuSrWxe5A27mBRb3bUOvt8u/rqKNzT4r812hq /8zaV7RYsB2En0AoRVyonOWCab+zXIkC9LC2rWz+UZpFaiM6NRRlW78Tpj4ag/+BXgU+1DXX/X0 T+Bpb4952j1vR7dR9+WeApgLOTXo9T2FlOQeAxYIF/65UN2ReZv77IijLREwpZDphoLP5n/aXgZ EQWKhjtoD0qQ== X-Google-Smtp-Source: AGHT+IE7lHhHjkKOsMhyBiKOKtjK0j3mfs2g1/yj+Xj0Ks4LIQgWNdA1JFuNUbEDKSnI9fAu6Kipyg== X-Received: by 2002:a05:6a00:230a:b0:781:16de:cc1a with SMTP id d2e1a72fcca58-7a220d37785mr21996238b3a.32.1761034138761; Tue, 21 Oct 2025 01:08:58 -0700 (PDT) Received: from Shardul.. ([223.185.42.221]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-7a22ff15829sm10528468b3a.11.2025.10.21.01.08.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Oct 2025 01:08:58 -0700 (PDT) From: Shardul Bankar To: bpf@vger.kernel.org Cc: shardulsb08@gmail.com, Eduard Zingerman , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v3 bpf] bpf: liveness: clarify get_outer_instance() handling in propagate_to_outer_instance() Date: Tue, 21 Oct 2025 13:38:46 +0530 Message-Id: <20251021080849.860072-1-shardulsb08@gmail.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit propagate_to_outer_instance() calls get_outer_instance() and uses the returned pointer to reset and commit stack write marks. Under normal conditions, update_instance() guarantees that an outer instance exists, so get_outer_instance() cannot return an ERR_PTR. However, explicitly checking for IS_ERR(outer_instance) makes this code more robust and self-documenting. It reduces cognitive load when reading the control flow and silences potential false-positive reports from static analysis or automated tooling. No functional change intended. Reported-by: kernel-patches-review-bot (https://github.com/kernel-patches/bpf/pull/10006#issuecomment-3409419240) Suggested-by: Eduard Zingerman Signed-off-by: Shardul Bankar --- kernel/bpf/liveness.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/bpf/liveness.c b/kernel/bpf/liveness.c index 3c611aba7f52..ae31f9ee4994 100644 --- a/kernel/bpf/liveness.c +++ b/kernel/bpf/liveness.c @@ -522,6 +522,8 @@ static int propagate_to_outer_instance(struct bpf_verifier_env *env, this_subprog_start = callchain_subprog_start(callchain); outer_instance = get_outer_instance(env, instance); + if (IS_ERR(outer_instance)) + return PTR_ERR(outer_instance); callsite = callchain->callsites[callchain->curframe - 1]; reset_stack_write_marks(env, outer_instance, callsite); -- 2.34.1