mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-09 22:14:36 -04:00
b165585795
syzkaller was able to trigger the following warning in
do_dentry_open():
WARNING: CPU: 1 PID: 4508 at fs/open.c:778 do_dentry_open+0x4ad/0xe40 fs/open.c:778
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 4508 Comm: syz-executor867 Not tainted 4.17.0+ #90
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
[...]
vfs_open+0x139/0x230 fs/open.c:908
do_last fs/namei.c:3370 [inline]
path_openat+0x1717/0x4dc0 fs/namei.c:3511
do_filp_open+0x249/0x350 fs/namei.c:3545
do_sys_open+0x56f/0x740 fs/open.c:1101
__do_sys_openat fs/open.c:1128 [inline]
__se_sys_openat fs/open.c:1122 [inline]
__x64_sys_openat+0x9d/0x100 fs/open.c:1122
do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Problem was that prog and map inodes in bpf fs did not
implement a dummy file open operation that would return an
error. The patch in do_dentry_open() checks whether f_ops
are present and if not bails out with an error. While this
may be fine, we really shouldn't be throwing a warning
though. Thus follow the model similar to bad_file_ops and
reject the request unconditionally with -EIO.
Fixes: b2197755b2 ("bpf: add support for persistent maps/progs")
Reported-by: syzbot+2e7fcab0f56fdbb330b8@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.