luck/tmp_suning_uos_patched
1
0
Fork 1
Code Issues Pull Requests Packages Projects Releases Wiki Activity

fat: Fix _fat_bmap() race

Browse Source 
fat_get_cluster() assumes the requested blocknr isn't truncated during
read. _fat_bmap() doesn't follow this rule.

This protects it by ->i_mutex.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
OGAWA Hirofumi 2008-11-06 12:53:56 -08:00 committed by Linus Torvalds
parent dfc209c006
commit fa93ca18a8
1 changed files with 8 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
fs/fat/inode.c
View File

@ -199,7 +199,14 @@ static ssize_t fat_direct_IO(int rw, struct kiocb *iocb,
static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
{
return generic_block_bmap(mapping, block, fat_get_block);
sector_t blocknr;
/* fat_get_cluster() assumes the requested blocknr isn't truncated. */
mutex_lock(&mapping->host->i_mutex);
blocknr = generic_block_bmap(mapping, block, fat_get_block);
mutex_unlock(&mapping->host->i_mutex);
return blocknr;
}
static const struct address_space_operations fat_aops = {