mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-02 23:27:06 +00:00
Code Issues Releases Wiki Activity

ext4: sysfs: print ext4_super_block fields as little-endian

Browse source 
commit a4d2aadca1 upstream.

While working on extended rand for last_error/first_error timestamps,
I noticed that the endianess is wrong; we access the little-endian
fields in struct ext4_super_block as native-endian when we print them.

This adds a special case in ext4_attr_show() and ext4_attr_store()
to byteswap the superblock fields if needed.

In older kernels, this code was part of super.c, it got moved to
sysfs.c in linux-4.4.

Cc: stable@vger.kernel.org
Fixes: 52c198c682 ("ext4: add sysfs entry showing whether the fs contains errors")
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Arnd Bergmann 2018-07-29 15:48:00 -04:00 committed by Greg Kroah-Hartman
parent 9c2860f456
commit e0cfc1c92e
1 changed files with 10 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

13
fs/ext4/sysfs.c
View file

@ -277,8 +277,12 @@ static ssize_t ext4_attr_show(struct kobject *kobj,
case attr_pointer_ui:
if (!ptr)
return 0;
return snprintf(buf, PAGE_SIZE, "%u\n",
*((unsigned int *) ptr));
if (a->attr_ptr == ptr_ext4_super_block_offset)
return snprintf(buf, PAGE_SIZE, "%u\n",
le32_to_cpup(ptr));
else
return snprintf(buf, PAGE_SIZE, "%u\n",
*((unsigned int *) ptr));
case attr_pointer_atomic:
if (!ptr)
return 0;
@ -311,7 +315,10 @@ static ssize_t ext4_attr_store(struct kobject *kobj,
ret = kstrtoul(skip_spaces(buf), 0, &t);
if (ret)
return ret;
*((unsigned int *) ptr) = t;
if (a->attr_ptr == ptr_ext4_super_block_offset)
*((__le32 *) ptr) = cpu_to_le32(t);
else
*((unsigned int *) ptr) = t;
return len;
case attr_inode_readahead:
return inode_readahead_blks_store(a, sbi, buf, len);