From: Theodore Ts'o Subject: [PATCH 18/42] ext4: fix #11321: create /proc/ext4/*/stats more carefully Date: Thu, 9 Oct 2008 00:05:36 -0400 Message-ID: <1223525160-9887-19-git-send-email-tytso@mit.edu> References: <1223525160-9887-1-git-send-email-tytso@mit.edu> <1223525160-9887-2-git-send-email-tytso@mit.edu> <1223525160-9887-3-git-send-email-tytso@mit.edu> <1223525160-9887-4-git-send-email-tytso@mit.edu> <1223525160-9887-5-git-send-email-tytso@mit.edu> <1223525160-9887-6-git-send-email-tytso@mit.edu> <1223525160-9887-7-git-send-email-tytso@mit.edu> <1223525160-9887-8-git-send-email-tytso@mit.edu> <1223525160-9887-9-git-send-email-tytso@mit.edu> <1223525160-9887-10-git-send-email-tytso@mit.edu> <1223525160-9887-11-git-send-email-tytso@mit.edu> <1223525160-9887-12-git-send-email-tytso@mit.edu> <1223525160-9887-13-git-send-email-tytso@mit.edu> <1223525160-9887-14-git-send-email-tytso@mit.edu> <1223525160-9887-15-git-send-email-tytso@mit.edu> <1223525160-9887-16-git-send-email-tytso@mit.edu> <1223525160-9887-17-git-send-email-tytso@mit.edu> <1223525160-9887-18-git-send-email-tytso@mit.edu> Cc: Alexey Dobriyan , "Theodore Ts'o" To: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: Received: from www.church-of-our-saviour.org ([69.25.196.31]:54526 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757568AbYJIEGN (ORCPT ); Thu, 9 Oct 2008 00:06:13 -0400 In-Reply-To: <1223525160-9887-18-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: From: Alexey Dobriyan ext4 creates per-suberblock directory in /proc/ext4/ . Name used as basis is taken from bdevname, which, surprise, can contain slash. However, proc while allowing to use proc_create("a/b", parent) form of PDE creation, assumes that parent/a was already created. bdevname in question is 'cciss/c0d0p9', directory is not created and all this stuff goes directly into /proc (which is real bug). Warning comes when _second_ partition is mounted. http://bugzilla.kernel.org/show_bug.cgi?id=11321 Signed-off-by: Alexey Dobriyan Signed-off-by: "Theodore Ts'o" --- fs/ext4/mballoc.c | 16 +++++++++++++--- 1 files changed, 13 insertions(+), 3 deletions(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index c7b0dea..af48548 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2786,14 +2786,20 @@ static int ext4_mb_init_per_dev_proc(struct super_block *sb) mode_t mode = S_IFREG | S_IRUGO | S_IWUSR; struct ext4_sb_info *sbi = EXT4_SB(sb); struct proc_dir_entry *proc; - char devname[64]; + char devname[BDEVNAME_SIZE], *p; if (proc_root_ext4 == NULL) { sbi->s_mb_proc = NULL; return -EINVAL; } bdevname(sb->s_bdev, devname); + p = devname; + while ((p = strchr(p, '/'))) + *p = '!'; + sbi->s_mb_proc = proc_mkdir(devname, proc_root_ext4); + if (!sbi->s_mb_proc) + goto err_create_dir; MB_PROC_HANDLER(EXT4_MB_STATS_NAME, stats); MB_PROC_HANDLER(EXT4_MB_MAX_TO_SCAN_NAME, max_to_scan); @@ -2805,7 +2811,6 @@ static int ext4_mb_init_per_dev_proc(struct super_block *sb) return 0; err_out: - printk(KERN_ERR "EXT4-fs: Unable to create %s\n", devname); remove_proc_entry(EXT4_MB_GROUP_PREALLOC, sbi->s_mb_proc); remove_proc_entry(EXT4_MB_STREAM_REQ, sbi->s_mb_proc); remove_proc_entry(EXT4_MB_ORDER2_REQ, sbi->s_mb_proc); @@ -2814,6 +2819,8 @@ err_out: remove_proc_entry(EXT4_MB_STATS_NAME, sbi->s_mb_proc); remove_proc_entry(devname, proc_root_ext4); sbi->s_mb_proc = NULL; +err_create_dir: + printk(KERN_ERR "EXT4-fs: Unable to create %s\n", devname); return -ENOMEM; } @@ -2821,12 +2828,15 @@ err_out: static int ext4_mb_destroy_per_dev_proc(struct super_block *sb) { struct ext4_sb_info *sbi = EXT4_SB(sb); - char devname[64]; + char devname[BDEVNAME_SIZE], *p; if (sbi->s_mb_proc == NULL) return -EINVAL; bdevname(sb->s_bdev, devname); + p = devname; + while ((p = strchr(p, '/'))) + *p = '!'; remove_proc_entry(EXT4_MB_GROUP_PREALLOC, sbi->s_mb_proc); remove_proc_entry(EXT4_MB_STREAM_REQ, sbi->s_mb_proc); remove_proc_entry(EXT4_MB_ORDER2_REQ, sbi->s_mb_proc); -- 1.5.6.1.205.ge2c7.dirty