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| author | Al Viro <viro@zeniv.linux.org.uk> | 2024-07-20 01:48:34 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2024-11-03 01:28:07 -0500 |
| commit | 66635b0776243ff567db08601546b7f26b67dd08 (patch) | |
| tree | 9f7c80007c9a47864612edb5dacd84ce3eb7d8c9 /drivers/xen | |
| parent | 89359897983825dbfc08578e7ee807aaf24d9911 (diff) | |
| download | lwn-66635b0776243ff567db08601546b7f26b67dd08.tar.gz lwn-66635b0776243ff567db08601546b7f26b67dd08.zip | |
assorted variants of irqfd setup: convert to CLASS(fd)
in all of those failure exits prior to fdget() are plain returns and
the only thing done after fdput() is (on failure exits) a kfree(),
which can be done before fdput() just fine.
NOTE: in acrn_irqfd_assign() 'fail:' failure exit is wrong for
eventfd_ctx_fileget() failure (we only want fdput() there) and once
we stop doing that, it doesn't need to check if eventfd is NULL or
ERR_PTR(...) there.
NOTE: in privcmd we move fdget() up before the allocation - more
to the point, before the copy_from_user() attempt.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'drivers/xen')
| -rw-r--r-- | drivers/xen/privcmd.c | 17 |
1 files changed, 4 insertions, 13 deletions
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c index 79070494070d..0ca532614343 100644 --- a/drivers/xen/privcmd.c +++ b/drivers/xen/privcmd.c @@ -967,10 +967,11 @@ static int privcmd_irqfd_assign(struct privcmd_irqfd *irqfd) struct privcmd_kernel_irqfd *kirqfd, *tmp; unsigned long flags; __poll_t events; - struct fd f; void *dm_op; int ret, idx; + CLASS(fd, f)(irqfd->fd); + kirqfd = kzalloc(sizeof(*kirqfd) + irqfd->size, GFP_KERNEL); if (!kirqfd) return -ENOMEM; @@ -986,8 +987,7 @@ static int privcmd_irqfd_assign(struct privcmd_irqfd *irqfd) kirqfd->dom = irqfd->dom; INIT_WORK(&kirqfd->shutdown, irqfd_shutdown); - f = fdget(irqfd->fd); - if (!fd_file(f)) { + if (fd_empty(f)) { ret = -EBADF; goto error_kfree; } @@ -995,7 +995,7 @@ static int privcmd_irqfd_assign(struct privcmd_irqfd *irqfd) kirqfd->eventfd = eventfd_ctx_fileget(fd_file(f)); if (IS_ERR(kirqfd->eventfd)) { ret = PTR_ERR(kirqfd->eventfd); - goto error_fd_put; + goto error_kfree; } /* @@ -1028,20 +1028,11 @@ static int privcmd_irqfd_assign(struct privcmd_irqfd *irqfd) irqfd_inject(kirqfd); srcu_read_unlock(&irqfds_srcu, idx); - - /* - * Do not drop the file until the kirqfd is fully initialized, otherwise - * we might race against the EPOLLHUP. - */ - fdput(f); return 0; error_eventfd: eventfd_ctx_put(kirqfd->eventfd); -error_fd_put: - fdput(f); - error_kfree: kfree(kirqfd); return ret; |