From 095da6cbb6a1c54c19b11190218eb0fbac666b6d Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Mon, 16 Jan 2006 22:14:52 -0800 Subject: [PATCH] fuse: fix bitfield race Fix race in setting bitfields of fuse_conn. Spotted by Andrew Morton. The two fields ->connected and ->mounted were always changed with the fuse_lock held. But other bitfields in the same structure were changed without the lock. In theory this could lead to losing the assignment of even the ones under lock. The chosen solution is to change these two fields to be a full unsigned type. The other bitfields aren't "important" enough to warrant the extra complexity of full locking or changing them to bitops. For all bitfields document why they are safe wrt. concurrent assignments. Also make the initialization of the 'num_waiting' atomic counter explicit. Signed-off-by: Miklos Szeredi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fuse/inode.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/fuse/inode.c') diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 8683e7254d5..c755a0440a6 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -397,6 +397,7 @@ static struct fuse_conn *new_conn(void) init_rwsem(&fc->sbput_sem); kobj_set_kset_s(fc, connections_subsys); kobject_init(&fc->kobj); + atomic_set(&fc->num_waiting, 0); for (i = 0; i < FUSE_MAX_OUTSTANDING; i++) { struct fuse_req *req = fuse_request_alloc(); if (!req) { @@ -492,6 +493,7 @@ static void fuse_send_init(struct fuse_conn *fc) to be exactly one request available */ struct fuse_req *req = fuse_get_request(fc); struct fuse_init_in *arg = &req->misc.init_in; + arg->major = FUSE_KERNEL_VERSION; arg->minor = FUSE_KERNEL_MINOR_VERSION; req->in.h.opcode = FUSE_INIT; -- cgit v1.2.3-70-g09d2