From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934688AbbLPRwa (ORCPT ); Wed, 16 Dec 2015 12:52:30 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:50086 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966646AbbLPRks (ORCPT ); Wed, 16 Dec 2015 12:40:48 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Bart Van Assche , Christoph Hellwig , Hannes Reinecke , "Martin K. Petersen" , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 100/128] Fix a memory leak in scsi_host_dev_release() Date: Wed, 16 Dec 2015 09:39:00 -0800 Message-Id: <1450287568-19808-101-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1450287568-19808-1-git-send-email-kamal@canonical.com> References: <1450287568-19808-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19.8-ckt12 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Bart Van Assche commit b49493f99690c8eaacfbc635bafaad629ea2c036 upstream. Avoid that kmemleak reports the following memory leak if a SCSI LLD calls scsi_host_alloc() and scsi_host_put() but neither scsi_host_add() nor scsi_host_remove(). The following shell command triggers that scenario: for ((i=0; i<2; i++)); do srp_daemon -oac | while read line; do echo $line >/sys/class/infiniband_srp/srp-mlx4_0-1/add_target done done unreferenced object 0xffff88021b24a220 (size 8): comm "srp_daemon", pid 56421, jiffies 4295006762 (age 4240.750s) hex dump (first 8 bytes): 68 6f 73 74 35 38 00 a5 host58.. backtrace: [] kmemleak_alloc+0x7a/0xc0 [] __kmalloc_track_caller+0xfe/0x160 [] kvasprintf+0x5b/0x90 [] kvasprintf_const+0x8d/0xb0 [] kobject_set_name_vargs+0x3c/0xa0 [] dev_set_name+0x3c/0x40 [] scsi_host_alloc+0x327/0x4b0 [] srp_create_target+0x4e/0x8a0 [ib_srp] [] dev_attr_store+0x1b/0x20 [] sysfs_kf_write+0x4a/0x60 [] kernfs_fop_write+0x14e/0x180 [] __vfs_write+0x2f/0xf0 [] vfs_write+0xa4/0x100 [] SyS_write+0x54/0xc0 [] entry_SYSCALL_64_fastpath+0x12/0x6f Signed-off-by: Bart Van Assche Reviewed-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Reviewed-by: Sagi Grimberg Reviewed-by: Lee Duncan Cc: Christoph Hellwig Cc: Hannes Reinecke Signed-off-by: Martin K. Petersen Signed-off-by: Kamal Mostafa --- drivers/scsi/hosts.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 8bb173e..7d647a3 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -326,6 +326,17 @@ static void scsi_host_dev_release(struct device *dev) kfree(queuedata); } + if (shost->shost_state == SHOST_CREATED) { + /* + * Free the shost_dev device name here if scsi_host_alloc() + * and scsi_host_put() have been called but neither + * scsi_host_add() nor scsi_host_remove() has been called. + * This avoids that the memory allocated for the shost_dev + * name is leaked. + */ + kfree(dev_name(&shost->shost_dev)); + } + scsi_destroy_command_freelist(shost); if (shost_use_blk_mq(shost)) { if (shost->tag_set.tags) -- 1.9.1