From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 6F884481665; Tue, 25 Aug 2026 13:47:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787665679; cv=none; b=FCGggrvWLtgNznXfOFyXpbUubYnimT42mFjM2c9sSMkE6/awNPmHG7YXnAXE+K1QrRc24m2dI2QdY5Vmyb7L/X6mUyGYNc98YA2Z3Ik/RkrqoxvreOaL9ZvGBLISVq+/AICClvJ/NWNZbBe9QeKqdx2lTEm+4zJ7SlEYfHC37KM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787665679; c=relaxed/simple; bh=OIGoCRyh87I0NckVj9a8FWBawreFKu3MvAMVGvJ+06k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=HIpvfcyJYI2qHjeRCPPgKdrMp7jvdfEAqFmXMtK8um9LfGyMgC6nQ3GutZ3FrXSgIEam8zWtsqiQNwnYyVfuvL4RCJKfBp1qb7A+j5nCN8rWKYfwJ3Q/4ZrV+vXt7MiJ95SgzP8du7z2hMWTk+h6BzbQm+TVshYvTYJQlSmkEfQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=cTS2kAkf; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="cTS2kAkf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 707FC1F000E9; Tue, 25 Aug 2026 13:47:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787665678; bh=l3RBVZF6TLqa0pjw3hHKkqKZTUdStuhn/BlvLj7+E/U=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=cTS2kAkfpjr30ovv5IW9vnpCvGYp1Rw0yyoBBD/Wki5ANiPG1G5thgtBsXDNFRcV2 718vjhbIicEAlaeVYbwel2vsYAL/yzTtOlfQnPOvDX+9c+w66m2RlO25DKmmYADklZ DL7Kd1Jk2+3QnaK+W6LCiEf7H1C00KrWyLFGV8Pw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Farhan Ali , Matthew Rosato , Eric Farman , Christian Borntraeger Subject: [PATCH 6.6 30/87] s390/vfio_ccw: Free all memory if cp_init() fails Date: Tue, 25 Aug 2026 15:25:53 +0200 Message-ID: <20260825132543.026926468@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260825132541.813800447@linuxfoundation.org> References: <20260825132541.813800447@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Farman commit 74186c2968f8f756ac3226b545b598457c910c75 upstream. The routine cp_free() is called to unpin/free any memory once an I/O is completed successfully, or if cp_prefetch() fails. But if cp_init() fails, and cp->initialized is not enabled, the same routine cannot be used to free all the memory. An attempt to address this exists in ccwchain_handle_ccw(), where a single call to ccwchain_free() is made for the currently-processed CCW segment. But this will leak other segments (created as a result of a Transfer in Channel) that had been allocated as part of the same channel program. Address this by performing the cleanup outside of the recursive ccwchain_handle_ccw()/ccwchain_loop_tic() logic. Fixes: 8b515be512a2 ("vfio-ccw: Fix memory leak and don't call cp_free in cp_init") Cc: stable@vger.kernel.org Reviewed-by: Farhan Ali Reviewed-by: Matthew Rosato Signed-off-by: Eric Farman Signed-off-by: Christian Borntraeger [farman@linux.ibm.com: resolve build error] Signed-off-by: Eric Farman Signed-off-by: Greg Kroah-Hartman --- drivers/s390/cio/vfio_ccw_cp.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -450,9 +450,6 @@ static int ccwchain_handle_ccw(u32 cda, /* Loop for tics on this new chain. */ ret = ccwchain_loop_tic(chain, cp); - if (ret) - ccwchain_free(chain); - return ret; } @@ -481,6 +478,23 @@ static int ccwchain_loop_tic(struct ccwc return 0; } +static int ccwchain_build_ccws(u32 cda, struct channel_program *cp) +{ + struct ccwchain *chain, *temp; + int ret; + + ret = ccwchain_handle_ccw(cda, cp); + + if (ret) { + /* Cleanup if an error occurred */ + list_for_each_entry_safe(chain, temp, &cp->ccwchain_list, next) { + ccwchain_free(chain); + } + } + + return ret; +} + static int ccwchain_fetch_tic(struct ccw1 *ccw, struct channel_program *cp) { @@ -728,7 +742,7 @@ int cp_init(struct channel_program *cp, memcpy(&cp->orb, orb, sizeof(*orb)); /* Build a ccwchain for the first CCW segment */ - ret = ccwchain_handle_ccw(orb->cmd.cpa, cp); + ret = ccwchain_build_ccws(orb->cmd.cpa, cp); if (!ret) cp->initialized = true;