leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

block: xen-blkfront: Fix possible NULL ptr dereference

Browse Source 
In the blkif_release function the bdget_disk() call might returns
a NULL ptr which might be dereferenced on bdev->bd_openers checking

Signed-off-by: Felipe Pena <felipensp@gmail.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v2: Added WARN per Roger's suggestion]
This commit is contained in:
Felipe Pena 2013-11-09 13:36:09 -02:00 committed by Konrad Rzeszutek Wilk
parent 427bfe07e6
commit 2f089cb89d
1 changed files with 5 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/block/xen-blkfront.c
View File

@ -2011,6 +2011,10 @@ static void blkif_release(struct gendisk *disk, fmode_t mode)
bdev = bdget_disk(disk, 0); bdev = bdget_disk(disk, 0);
if (!bdev) {
WARN(1, "Block device %s yanked out from us!\n", disk->disk_name);
goto out_mutex;
}
if (bdev->bd_openers) if (bdev->bd_openers)
goto out; goto out;
@ -2041,6 +2045,7 @@ static void blkif_release(struct gendisk *disk, fmode_t mode)
out: out:
bdput(bdev); bdput(bdev);
out_mutex:
mutex_unlock(&blkfront_mutex); mutex_unlock(&blkfront_mutex);
} }