From mboxrd@z Thu Jan 1 00:00:00 1970 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 B39D035AC00 for ; Sat, 28 Feb 2026 18:17:53 +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=1772302673; cv=none; b=R4CIpsSt/E0svaeCAqVvQKkCpWus+lGfqjwa/UQKuIs7wFwndlu2z5gCulABebAuhKUJPdT9Wa6xl9mrNiwE9TH6GTJnSUPqwj4tpa5Wr4A09rmvQruQeyXCNRwPHKaEa/uw5Ls3pF7SgMTYC3VFyZcR96Oolj2qMf0NtbKy5fU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302673; c=relaxed/simple; bh=FfUHppN2aS9CzHXhDjZLuiSFkwQR2ELxDCGP6b1C/+4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dIWMcayPxitv3VqNJDO2y32kbb0gS++/iUw74APQHCNW0owSfAbtzD1eBjZKpoSw+owJT2H972m6JeoO5HpuMv+i2JWu1PlFm/+ixM6V8fCGUThUrLetBn8nM3LDy8QimjoyrMjk0zLDp7nCFsuHecDcw/csH08PKo6FdDKMv3k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rYj5fYxX; 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="rYj5fYxX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 12504C19424; Sat, 28 Feb 2026 18:17:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302673; bh=FfUHppN2aS9CzHXhDjZLuiSFkwQR2ELxDCGP6b1C/+4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rYj5fYxXVXxj3PyPqp9KEeoS0hnZW1wsKtoVCTDpcf9ppI89XJk/hzs7vSEi4KYv0 oqD/Ge8XXhf5xx031TzIgWeP5gfGz1BNFtHRcL2gk24ToR3n8+tNvrGNw1KmGiuvkP dRZGo7fA7Wm+MOt9xAOPSLEIqxQ/FX8SsUpV7oHIxRfClm1bHjYU5gKYAXruIHylop psP1m+2YbeDlxwBRCNvDy9Q3A1f1UHoiXretXSMhvZxTwk6NItz3m3LnhFIxGtgFQh A6VJYUZItBSqgDnxned4K5j/ZLlFc4GOUoq5eNNX/AiN6KKQMvl6blkT8OXtNCkcV6 01QmA9wvBWwaw== From: Sasha Levin To: patches@lists.linux.dev Cc: Salah Triki , Vineeth Vijayan , Heiko Carstens , Sasha Levin Subject: [PATCH 5.10 022/147] s390/cio: Fix device lifecycle handling in css_alloc_subchannel() Date: Sat, 28 Feb 2026 13:15:30 -0500 Message-ID: <20260228181736.1605592-22-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228181736.1605592-1-sashal@kernel.org> References: <20260228181736.1605592-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Salah Triki [ Upstream commit f65c75b0b9b5a390bc3beadcde0a6fbc3ad118f7 ] `css_alloc_subchannel()` calls `device_initialize()` before setting up the DMA masks. If `dma_set_coherent_mask()` or `dma_set_mask()` fails, the error path frees the subchannel structure directly, bypassing the device model reference counting. Once `device_initialize()` has been called, the embedded struct device must be released via `put_device()`, allowing the release callback to free the container structure. Fix the error path by dropping the initial device reference with `put_device()` instead of calling `kfree()` directly. This ensures correct device lifetime handling and avoids potential use-after-free or double-free issues. Fixes: e5dcf0025d7af ("s390/css: move subchannel lock allocation") Signed-off-by: Salah Triki Reviewed-by: Vineeth Vijayan Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin --- drivers/s390/cio/css.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c index cf2c3c4c590f9..e5e20ea850aad 100644 --- a/drivers/s390/cio/css.c +++ b/drivers/s390/cio/css.c @@ -241,7 +241,7 @@ struct subchannel *css_alloc_subchannel(struct subchannel_id schid, return sch; err: - kfree(sch); + put_device(&sch->dev); return ERR_PTR(ret); } -- 2.51.0