From 82bca17dd526ee0304141a7fd978811cda9e92b4 Mon Sep 17 00:00:00 2001 From: Mathias Krause Date: Sun, 4 Feb 2024 08:51:52 +0100 Subject: bcachefs: install fd later to avoid race with close Calling fd_install() makes a file reachable for userland, including the possibility to close the file descriptor, which leads to calling its 'release' hook. If that happens before the code had a chance to bump the reference of the newly created task struct, the release callback will call put_task_struct() too early, leading to the premature destruction of the kernel thread. Avoid that race by calling fd_install() later, after all the setup is done. Fixes: 1c6fdbd8f246 ("bcachefs: Initial commit") Signed-off-by: Mathias Krause Signed-off-by: Kent Overstreet --- fs/bcachefs/chardev.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/bcachefs/chardev.c b/fs/bcachefs/chardev.c index 4bb88aefed12..64000c8da5ee 100644 --- a/fs/bcachefs/chardev.c +++ b/fs/bcachefs/chardev.c @@ -392,10 +392,9 @@ static long bch2_ioctl_data(struct bch_fs *c, goto err; } - fd_install(fd, file); - get_task_struct(ctx->thread); wake_up_process(ctx->thread); + fd_install(fd, file); return fd; err: -- cgit v1.2.3