From e0edd3c65aa5b53e20280565a7ce11675eb7ed6b Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 4 Mar 2009 11:57:20 -0800 Subject: sysfs: don't block indefinitely for unmapped files. Modify sysfs bin files so that we can remove the bin file while they are still mapped. When the kobject is removed we unmap the bin file and arrange for future accesses to the mapping to receive SIGBUS. Implementing this prevents a nasty DOS when pci devices are hot plugged and unplugged. Where if any of their resources were mmaped the kernel could not free up their pci resources or release their pci data structures. [akpm@linux-foundation.org: remove unused var] Signed-off-by: Eric W. Biederman Cc: Jesse Barnes Acked-by: Tejun Heo Cc: Kay Sievers Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index f13d852..66aeb4f 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -609,6 +609,7 @@ void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) sysfs_drop_dentry(sd); sysfs_deactivate(sd); + unmap_bin_file(sd); sysfs_put(sd); } } -- cgit v1.1