diff options
| author | Wang YanQing <udknight@gmail.com> | 2015-06-23 18:54:45 +0800 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2015-07-01 01:50:06 -0400 |
| commit | 1af95de6f0119d5bde02d3a811a9f3a3661e954e (patch) | |
| tree | 703a419f2f4c0203683b9030450d54bfaf1f76d8 | |
| parent | 2adc376c551943a07170cbe70f43e6d6065f8906 (diff) | |
fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
Execution of get_anon_bdev concurrently and preemptive kernel all
could bring race condition, it isn't enough to check dev against
its upper limitation with equality operator only.
This patch fix it.
Signed-off-by: Wang YanQing <udknight@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| -rw-r--r-- | fs/super.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/super.c b/fs/super.c index 928c20f47af9..b61372354f2b 100644 --- a/fs/super.c +++ b/fs/super.c @@ -842,7 +842,7 @@ int get_anon_bdev(dev_t *p) else if (error) return -EAGAIN; - if (dev == (1 << MINORBITS)) { + if (dev >= (1 << MINORBITS)) { spin_lock(&unnamed_dev_lock); ida_remove(&unnamed_dev_ida, dev); if (unnamed_dev_start > dev) |