5260dd3ed1
In order to fix this data-race found by KCSAN [1], switch to u64_stats_t helpers. They provide all the needed annotations, without adding extra cost. [1] BUG: KCSAN: data-race in tun_get_user / tun_net_get_stats64 read to 0xffffe8ffffd8aca8 of 8 bytes by task 4882 on cpu 0: tun_net_get_stats64+0x9b/0x230 drivers/net/tun.c:1171 dev_get_stats+0x89/0x1e0 net/core/dev.c:9103 rtnl_fill_stats+0x56/0x370 net/core/rtnetlink.c:1177 rtnl_fill_ifinfo+0xd3b/0x2100 net/core/rtnetlink.c:1667 rtmsg_ifinfo_build_skb+0xb0/0x150 net/core/rtnetlink.c:3472 rtmsg_ifinfo_event.part.0+0x4e/0xb0 net/core/rtnetlink.c:3504 rtmsg_ifinfo_event net/core/rtnetlink.c:3515 [inline] rtmsg_ifinfo+0x85/0x90 net/core/rtnetlink.c:3513 __dev_notify_flags+0x18b/0x200 net/core/dev.c:7649 dev_change_flags+0xb8/0xe0 net/core/dev.c:7691 dev_ifsioc+0x201/0x6a0 net/core/dev_ioctl.c:237 dev_ioctl+0x149/0x660 net/core/dev_ioctl.c:489 sock_do_ioctl+0xdb/0x230 net/socket.c:1061 sock_ioctl+0x3a3/0x5e0 net/socket.c:1189 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x991/0xc60 fs/ioctl.c:696 write to 0xffffe8ffffd8aca8 of 8 bytes by task 4883 on cpu 1: tun_get_user+0x1d94/0x2ba0 drivers/net/tun.c:2002 tun_chr_write_iter+0x79/0xd0 drivers/net/tun.c:2022 call_write_iter include/linux/fs.h:1895 [inline] new_sync_write+0x388/0x4a0 fs/read_write.c:483 __vfs_write+0xb1/0xc0 fs/read_write.c:496 __kernel_write+0xb8/0x240 fs/read_write.c:515 write_pipe_buf+0xb6/0xf0 fs/splice.c:794 splice_from_pipe_feed fs/splice.c:500 [inline] __splice_from_pipe+0x248/0x480 fs/splice.c:624 splice_from_pipe+0xbb/0x100 fs/splice.c:659 default_file_splice_write+0x45/0x90 fs/splice.c:806 do_splice_from fs/splice.c:848 [inline] direct_splice_actor+0xa0/0xc0 fs/splice.c:1020 splice_direct_to_actor+0x215/0x510 fs/splice.c:975 do_splice_direct+0x161/0x1e0 fs/splice.c:1063 do_sendfile+0x384/0x7f0 fs/read_write.c:1464 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 4883 Comm: syz-executor.1 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.