a343993c51
syzkaller reported a warning from xdp_umem_pin_pages():
WARNING: CPU: 1 PID: 4537 at mm/slab_common.c:996 kmalloc_slab+0x56/0x70 mm/slab_common.c:996
...
__do_kmalloc mm/slab.c:3713 [inline]
__kmalloc+0x25/0x760 mm/slab.c:3727
kmalloc_array include/linux/slab.h:634 [inline]
kcalloc include/linux/slab.h:645 [inline]
xdp_umem_pin_pages net/xdp/xdp_umem.c:205 [inline]
xdp_umem_reg net/xdp/xdp_umem.c:318 [inline]
xdp_umem_create+0x5c9/0x10f0 net/xdp/xdp_umem.c:349
xsk_setsockopt+0x443/0x550 net/xdp/xsk.c:531
__sys_setsockopt+0x1bd/0x390 net/socket.c:1935
__do_sys_setsockopt net/socket.c:1946 [inline]
__se_sys_setsockopt net/socket.c:1943 [inline]
__x64_sys_setsockopt+0xbe/0x150 net/socket.c:1943
do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x49/0xbe
This is a warning about attempting to allocate more than
KMALLOC_MAX_SIZE memory. The request originates from userspace, and if
the request is too big, the kernel is free to deny its allocation. In
this patch, the failed allocation attempt is silenced with
__GFP_NOWARN.
Fixes: c0c77d8fb787 ("xsk: add user memory registration support sockopt")
Reported-by: syzbot+4abadc5d69117b346506@syzkaller.appspotmail.com
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.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.
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.