Matthew Wilcox (Oracle) 032146cda8 vfs: check fd has read access in kernel_read_file_from_fd()
If we open a file without read access and then pass the fd to a syscall
whose implementation calls kernel_read_file_from_fd(), we get a warning
from __kernel_read():

        if (WARN_ON_ONCE(!(file->f_mode & FMODE_READ)))

This currently affects both finit_module() and kexec_file_load(), but it
could affect other syscalls in the future.

Link: https://lkml.kernel.org/r/20211007220110.600005-1-willy@infradead.org
Fixes: b844f0ecbc56 ("vfs: define kernel_copy_file_from_fd()")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reported-by: Hao Sun <sunhao.th@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mimi Zohar <zohar@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-10-18 20:22:03 -10:00
..
2021-10-07 11:20:08 -07:00
2021-08-19 09:02:55 +09:00
2021-10-11 16:48:19 -07:00
2021-04-12 15:04:29 +02:00
2021-07-06 11:06:04 -07:00
2021-09-04 10:48:47 -07:00
2021-09-02 12:32:12 -07:00
2021-09-07 12:18:29 -07:00
2021-08-26 22:28:02 +02:00
2021-10-07 10:18:36 -05:00
2021-09-22 09:21:02 -07:00
2021-09-04 10:25:26 -07:00
2021-09-10 09:46:48 -07:00
2021-06-30 12:21:16 -07:00
2021-06-29 10:53:48 -07:00
2021-09-03 15:33:47 -07:00
2021-08-16 10:50:32 -06:00
2021-08-19 09:02:55 +09:00
2021-09-09 11:39:57 -07:00
\n
2021-08-30 10:24:50 -07:00
2021-08-31 11:13:35 -07:00
2021-09-09 13:25:49 -07:00
2021-09-11 14:48:42 -07:00
2021-08-31 11:06:32 -07:00
2021-06-29 10:53:48 -07:00
2021-08-18 22:08:24 +02:00
2021-08-10 17:57:22 +02:00