From patchwork Mon Nov 25 14:10:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 13884954 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 31FE21BB6BA; Mon, 25 Nov 2024 14:10:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732543849; cv=none; b=YjMn5qFgdk+yopGaah+voJMIW+yauLMyANKJ2Z8vUUpO3eewZrKH9to/zcyLBslG1Jk/UPAPyW244F4Y3q6qzjNRBOc6srTlz/b16zYIXIqU9ECfoA83FcV9RGEucvYbKXPnRRah15iSI3ytUwNnWdgjriRvjYyXuXS7NhNokEQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732543849; c=relaxed/simple; bh=IFLM84NiqCXkwMMafq8E9pIDiDKUxCWKPeY0cpJ2rUw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=iZEa/GxNtkItM2qRyu+Epa/M3ZU29xzThmfPtO94aT27Pn9ZJGwJrZcQjigz+ePYsdryu9crU/0+bawjgtYft08KZQn0N2DrMLQiRZfxEotsTavMfw5b4clFchQsonMNWfudBDSvq99OWmHUlQWBgzVU8T1JtMeEqwNzZij20Cc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=UJQiMV5J; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="UJQiMV5J" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E4EE0C4CED3; Mon, 25 Nov 2024 14:10:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1732543848; bh=IFLM84NiqCXkwMMafq8E9pIDiDKUxCWKPeY0cpJ2rUw=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=UJQiMV5JAOp/zBa2ro19c5jVETBKlkxuYKGDtBvNaK7H9IlEGoz1oKWQmUY8AiAma kh4aLXP5iCnsHEPtmh9tYVQpX/+AdLyrolYOZtlhp0BMsAmmPwS6diOILPAHBo8xCa E0HVWVMWvYfoFrtFlQPJdo2RhtmykHtEJVuxi7/x7wYgVAeGGUGl8jIYquxCCRR/U2 Sx7mnI9v0HP7aG3H74gQEnK1NEVSm8Msn5bsDPm8e39OlIt23UFiaq8VkXZJbmqFVH mcIEiCv1JEZOwlUUv67GMnplTXEclCovXk5tTeZpHmdZTZ1RUKbxCO1ZwWlf27pdA4 1kHDXMQqXB6RA== From: Christian Brauner Date: Mon, 25 Nov 2024 15:10:08 +0100 Subject: [PATCH v2 12/29] coredump: avoid pointless cred reference count bump Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241125-work-cred-v2-12-68b9d38bb5b2@kernel.org> References: <20241125-work-cred-v2-0-68b9d38bb5b2@kernel.org> In-Reply-To: <20241125-work-cred-v2-0-68b9d38bb5b2@kernel.org> To: Linus Torvalds Cc: Amir Goldstein , Miklos Szeredi , Al Viro , Jens Axboe , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Christian Brauner X-Mailer: b4 0.15-dev-355e8 X-Developer-Signature: v=1; a=openpgp-sha256; l=929; i=brauner@kernel.org; h=from:subject:message-id; bh=IFLM84NiqCXkwMMafq8E9pIDiDKUxCWKPeY0cpJ2rUw=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMaS7tHr6qhRmdDsHZjjbfeU+sPD0rSxeHumzSkeL207Y+ Tn5bHvUUcrCIMbFICumyOLQbhIut5ynYrNRpgbMHFYmkCEMXJwCMBHb6YwMp+/UygqFvV0n8848 t0Y0S4lz9c2avqY55/98dP4XtMXgIsNv9uaZUiJ1zbUZXbq3xDLFb2iGddwqZSl8rSF9QU3qszs PAA== X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 The creds are allocated via prepare_creds() which has already taken a reference. Signed-off-by: Christian Brauner --- fs/coredump.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/coredump.c b/fs/coredump.c index 0d3a65cac546db6710eb1337b0a9c4ec0ffff679..d48edb37bc35c0896d97a2f6a6cc259d8812f936 100644 --- a/fs/coredump.c +++ b/fs/coredump.c @@ -576,7 +576,7 @@ void do_coredump(const kernel_siginfo_t *siginfo) if (retval < 0) goto fail_creds; - old_cred = override_creds(get_new_cred(cred)); + old_cred = override_creds(cred); ispipe = format_corename(&cn, &cprm, &argv, &argc); @@ -781,7 +781,7 @@ void do_coredump(const kernel_siginfo_t *siginfo) kfree(argv); kfree(cn.corename); coredump_finish(core_dumped); - put_cred(revert_creds(old_cred)); + revert_creds(old_cred); fail_creds: put_cred(cred); fail: