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 358C61C07 for ; Wed, 28 Dec 2022 16:04:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A2EB1C433D2; Wed, 28 Dec 2022 16:04:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672243451; bh=Ep1LP9pPDoV+Knr4iC2+D7JKSWohoR/hKJvTo0Q0jwU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NZUmwIulXyuORAUlgVZehVL1Jlj2PSnSg1SnJQ44g1Kc0fZwZoc54R5et2V6oyHFM lDexMCOO2lYe2namJsBfd3OBfe/MvVD6UMVnBSkzcZuc+sFAOTKRk//3iK1yeDKxKj 5YB1WgbMH8g8WPv0dzEdS1eTJ7E2iOqGCc7mAnGc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yuan Can , Denis Efremov Subject: [PATCH 5.15 722/731] floppy: Fix memory leak in do_floppy_init() Date: Wed, 28 Dec 2022 15:43:49 +0100 Message-Id: <20221228144317.372691362@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20221228144256.536395940@linuxfoundation.org> References: <20221228144256.536395940@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Yuan Can commit f8ace2e304c5dd8a7328db9cd2b8a4b1b98d83ec upstream. A memory leak was reported when floppy_alloc_disk() failed in do_floppy_init(). unreferenced object 0xffff888115ed25a0 (size 8): comm "modprobe", pid 727, jiffies 4295051278 (age 25.529s) hex dump (first 8 bytes): 00 ac 67 5b 81 88 ff ff ..g[.... backtrace: [<000000007f457abb>] __kmalloc_node+0x4c/0xc0 [<00000000a87bfa9e>] blk_mq_realloc_tag_set_tags.part.0+0x6f/0x180 [<000000006f02e8b1>] blk_mq_alloc_tag_set+0x573/0x1130 [<0000000066007fd7>] 0xffffffffc06b8b08 [<0000000081f5ac40>] do_one_initcall+0xd0/0x4f0 [<00000000e26d04ee>] do_init_module+0x1a4/0x680 [<000000001bb22407>] load_module+0x6249/0x7110 [<00000000ad31ac4d>] __do_sys_finit_module+0x140/0x200 [<000000007bddca46>] do_syscall_64+0x35/0x80 [<00000000b5afec39>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 unreferenced object 0xffff88810fc30540 (size 32): comm "modprobe", pid 727, jiffies 4295051278 (age 25.529s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000007f457abb>] __kmalloc_node+0x4c/0xc0 [<000000006b91eab4>] blk_mq_alloc_tag_set+0x393/0x1130 [<0000000066007fd7>] 0xffffffffc06b8b08 [<0000000081f5ac40>] do_one_initcall+0xd0/0x4f0 [<00000000e26d04ee>] do_init_module+0x1a4/0x680 [<000000001bb22407>] load_module+0x6249/0x7110 [<00000000ad31ac4d>] __do_sys_finit_module+0x140/0x200 [<000000007bddca46>] do_syscall_64+0x35/0x80 [<00000000b5afec39>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 If the floppy_alloc_disk() failed, disks of current drive will not be set, thus the lastest allocated set->tag cannot be freed in the error handling path. A simple call graph shown as below: floppy_module_init() floppy_init() do_floppy_init() for (drive = 0; drive < N_DRIVE; drive++) blk_mq_alloc_tag_set() blk_mq_alloc_tag_set_tags() blk_mq_realloc_tag_set_tags() # set->tag allocated floppy_alloc_disk() blk_mq_alloc_disk() # error occurred, disks failed to allocated ->out_put_disk: for (drive = 0; drive < N_DRIVE; drive++) if (!disks[drive][0]) # the last disks is not set and loop break break; blk_mq_free_tag_set() # the latest allocated set->tag leaked Fix this problem by free the set->tag of current drive before jump to error handling path. Cc: stable@vger.kernel.org Fixes: 302cfee15029 ("floppy: use a separate gendisk for each media format") Signed-off-by: Yuan Can [efremov: added stable list, changed title] Signed-off-by: Denis Efremov Signed-off-by: Greg Kroah-Hartman --- drivers/block/floppy.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -4587,8 +4587,10 @@ static int __init do_floppy_init(void) goto out_put_disk; err = floppy_alloc_disk(drive, 0); - if (err) + if (err) { + blk_mq_free_tag_set(&tag_sets[drive]); goto out_put_disk; + } timer_setup(&motor_off_timer[drive], motor_off_callback, 0); }