| author | Chengguang Xu <cgxu519@gmx.com> | 2019-02-15 12:27:11 (GMT) |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-05-31 13:48:29 (GMT) |
| commit | bb22efcb872b8108131a38399ae910dcb0304770 (patch) | |
| tree | fa0cb94ef17f7e234afd1d890e8761f4090cdb43 | |
| parent | de90525fbe776d0faa3073aec11e6718eced518e (diff) | |
| download | common-bb22efcb872b8108131a38399ae910dcb0304770.zip common-bb22efcb872b8108131a38399ae910dcb0304770.tar.gz common-bb22efcb872b8108131a38399ae910dcb0304770.tar.bz2 | |
chardev: add additional check for minor range overlap
[ Upstream commit de36e16d1557a0b6eb328bc3516359a12ba5c25c ]
Current overlap checking cannot correctly handle
a case which is baseminor < existing baseminor &&
baseminor + minorct > existing baseminor + minorct.
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | fs/char_dev.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/char_dev.c b/fs/char_dev.c index 44a240c..a112a47 100644 --- a/fs/char_dev.c +++ b/fs/char_dev.c @@ -134,6 +134,12 @@ __register_chrdev_region(unsigned int major, unsigned int baseminor, ret = -EBUSY; goto out; } + + if (new_min < old_min && new_max > old_max) { + ret = -EBUSY; + goto out; + } + } cd->next = *cp; |