From: Theodore Ts'o Subject: [FOR-STABLE 02/20] ext4: fix #11321: create /proc/ext4/*/stats more carefully Date: Sun, 16 Nov 2008 11:05:22 -0500 Message-ID: <1226851540-8032-3-git-send-email-tytso@mit.edu> References: <1226851540-8032-1-git-send-email-tytso@mit.edu> <1226851540-8032-2-git-send-email-tytso@mit.edu> Cc: Ext4 Developers List , Alexey Dobriyan , "Theodore Ts'o" To: stable@kernel.org Return-path: Received: from www.church-of-our-saviour.ORG ([69.25.196.31]:44753 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753022AbYKPQii (ORCPT ); Sun, 16 Nov 2008 11:38:38 -0500 In-Reply-To: <1226851540-8032-2-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" (cherry picked from commit 899fc1a4cf404747de2666534d508804597ee22f) --- 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 e0e3a5e..0d51106 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2785,14 +2785,20 @@ 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); @@ -2804,7 +2810,6 @@ 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); @@ -2813,6 +2818,8 @@ 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; } @@ -2820,12 +2827,15 @@ 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); -- 1.6.0.4.8.g36f27.dirty