Given we recently extended the original bpf_map_area_alloc() helper in
commit fc970227 ("bpf: Add mmap() support for BPF_MAP_TYPE_ARRAY"),
we need to apply the same logic as in ff1c08e1 ("bpf: Change size
to u64 for bpf_map_{area_alloc, charge_init}()"). To avoid conflicts,
extend it for bpf-next.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Allow for audit messages to be emitted upon BPF program load and
unload for having a timeline of events. The load itself is in
syscall context, so additional info about the process initiating
the BPF prog creation can be logged and later directly correlated
to the unload event.

The only info really needed from BPF side is the globally unique
prog ID where then audit user space tooling can query / dump all
info needed about the specific BPF program right upon load event
and enrich the record, thus these changes needed here can be kept
small and non-intrusive to the core.

Raw example output:

  # auditctl -D
  # auditctl -a always,exit -F arch=x86_64 -S bpf
  # ausearch --start recent -m 1334
  [...]
  ----
  time->Wed Nov 20 12:45:51 2019
  type=PROCTITLE msg=audit(1574271951.590:8974): proctitle="./test_verifier"
  type=SYSCALL msg=audit(1574271951.590:8974): arch=c000003e syscall=321 success=yes exit=14 a0=5 a1=7ffe2d923e80 a2=78 a3=0 items=0 ppid=742 pid=949 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts0 ses=2 comm="test_verifier" exe="/root/bpf-next/tools/testing/selftests/bpf/test_verifier" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)
  type=UNKNOWN[1334] msg=audit(1574271951.590:8974): auid=0 uid=0 gid=0 ses=2 subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 pid=949 comm="test_verifier" exe="/root/bpf-next/tools/testing/selftests/bpf/test_verifier" prog-id=3260 event=LOAD
  ----
  time->Wed Nov 20 12:45:51 2019
type=UNKNOWN[1334] msg=audit(1574271951.590:8975): prog-id=3260 event=UNLOAD
  ----
  [...]
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NJiri Olsa <jolsa@kernel.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191120213816.8186-1-jolsa@kernel.org

Add ability to memory-map contents of BPF array map. This is extremely useful
for working with BPF global data from userspace programs. It allows to avoid
typical bpf_map_{lookup,update}_elem operations, improving both performance
and usability.

There had to be special considerations for map freezing, to avoid having
writable memory view into a frozen map. To solve this issue, map freezing and
mmap-ing is happening under mutex now:
  - if map is already frozen, no writable mapping is allowed;
  - if map has writable memory mappings active (accounted in map->writecnt),
    map freezing will keep failing with -EBUSY;
  - once number of writable memory mappings drops to zero, map freezing can be
    performed again.

Only non-per-CPU plain arrays are supported right now. Maps with spinlocks
can't be memory mapped either.

For BPF_F_MMAPABLE array, memory allocation has to be done through vmalloc()
to be mmap()'able. We also need to make sure that array data memory is
page-sized and page-aligned, so we over-allocate memory in such a way that
struct bpf_array is at the end of a single page of memory with array->value
being aligned with the start of the second page. On deallocation we need to
accomodate this memory arrangement to free vmalloc()'ed memory correctly.

One important consideration regarding how memory-mapping subsystem functions.
Memory-mapping subsystem provides few optional callbacks, among them open()
and close().  close() is called for each memory region that is unmapped, so
that users can decrease their reference counters and free up resources, if
necessary. open() is *almost* symmetrical: it's called for each memory region
that is being mapped, **except** the very first one. So bpf_map_mmap does
initial refcnt bump, while open() will do any extra ones after that. Thus
number of close() calls is equal to number of open() calls plus one more.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NSong Liu <songliubraving@fb.com>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/bpf/20191117172806.2195367-4-andriin@fb.com

Similarly to bpf_map's refcnt/usercnt, convert bpf_prog's refcnt to atomic64
and remove artificial 32k limit. This allows to make bpf_prog's refcounting
non-failing, simplifying logic of users of bpf_prog_add/bpf_prog_inc.

Validated compilation by running allyesconfig kernel build.
Suggested-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191117172806.2195367-3-andriin@fb.com

92117d84 ("bpf: fix refcnt overflow") turned refcounting of bpf_map into
potentially failing operation, when refcount reaches BPF_MAX_REFCNT limit
(32k). Due to using 32-bit counter, it's possible in practice to overflow
refcounter and make it wrap around to 0, causing erroneous map free, while
there are still references to it, causing use-after-free problems.

But having a failing refcounting operations are problematic in some cases. One
example is mmap() interface. After establishing initial memory-mapping, user
is allowed to arbitrarily map/remap/unmap parts of mapped memory, arbitrarily
splitting it into multiple non-contiguous regions. All this happening without
any control from the users of mmap subsystem. Rather mmap subsystem sends
notifications to original creator of memory mapping through open/close
callbacks, which are optionally specified during initial memory mapping
creation. These callbacks are used to maintain accurate refcount for bpf_map
(see next patch in this series). The problem is that open() callback is not
supposed to fail, because memory-mapped resource is set up and properly
referenced. This is posing a problem for using memory-mapping with BPF maps.

One solution to this is to maintain separate refcount for just memory-mappings
and do single bpf_map_inc/bpf_map_put when it goes from/to zero, respectively.
There are similar use cases in current work on tcp-bpf, necessitating extra
counter as well. This seems like a rather unfortunate and ugly solution that
doesn't scale well to various new use cases.

Another approach to solve this is to use non-failing refcount_t type, which
uses 32-bit counter internally, but, once reaching overflow state at UINT_MAX,
stays there. This utlimately causes memory leak, but prevents use after free.

But given refcounting is not the most performance-critical operation with BPF
maps (it's not used from running BPF program code), we can also just switch to
64-bit counter that can't overflow in practice, potentially disadvantaging
32-bit platforms a tiny bit. This simplifies semantics and allows above
described scenarios to not worry about failing refcount increment operation.

In terms of struct bpf_map size, we are still good and use the same amount of
space:

BEFORE (3 cache lines, 8 bytes of padding at the end):
struct bpf_map {
	const struct bpf_map_ops  * ops __attribute__((__aligned__(64))); /*     0     8 */
	struct bpf_map *           inner_map_meta;       /*     8     8 */
	void *                     security;             /*    16     8 */
	enum bpf_map_type  map_type;                     /*    24     4 */
	u32                        key_size;             /*    28     4 */
	u32                        value_size;           /*    32     4 */
	u32                        max_entries;          /*    36     4 */
	u32                        map_flags;            /*    40     4 */
	int                        spin_lock_off;        /*    44     4 */
	u32                        id;                   /*    48     4 */
	int                        numa_node;            /*    52     4 */
	u32                        btf_key_type_id;      /*    56     4 */
	u32                        btf_value_type_id;    /*    60     4 */
	/* --- cacheline 1 boundary (64 bytes) --- */
	struct btf *               btf;                  /*    64     8 */
	struct bpf_map_memory memory;                    /*    72    16 */
	bool                       unpriv_array;         /*    88     1 */
	bool                       frozen;               /*    89     1 */

	/* XXX 38 bytes hole, try to pack */

	/* --- cacheline 2 boundary (128 bytes) --- */
	atomic_t                   refcnt __attribute__((__aligned__(64))); /*   128     4 */
	atomic_t                   usercnt;              /*   132     4 */
	struct work_struct work;                         /*   136    32 */
	char                       name[16];             /*   168    16 */

	/* size: 192, cachelines: 3, members: 21 */
	/* sum members: 146, holes: 1, sum holes: 38 */
	/* padding: 8 */
	/* forced alignments: 2, forced holes: 1, sum forced holes: 38 */
} __attribute__((__aligned__(64)));

AFTER (same 3 cache lines, no extra padding now):
struct bpf_map {
	const struct bpf_map_ops  * ops __attribute__((__aligned__(64))); /*     0     8 */
	struct bpf_map *           inner_map_meta;       /*     8     8 */
	void *                     security;             /*    16     8 */
	enum bpf_map_type  map_type;                     /*    24     4 */
	u32                        key_size;             /*    28     4 */
	u32                        value_size;           /*    32     4 */
	u32                        max_entries;          /*    36     4 */
	u32                        map_flags;            /*    40     4 */
	int                        spin_lock_off;        /*    44     4 */
	u32                        id;                   /*    48     4 */
	int                        numa_node;            /*    52     4 */
	u32                        btf_key_type_id;      /*    56     4 */
	u32                        btf_value_type_id;    /*    60     4 */
	/* --- cacheline 1 boundary (64 bytes) --- */
	struct btf *               btf;                  /*    64     8 */
	struct bpf_map_memory memory;                    /*    72    16 */
	bool                       unpriv_array;         /*    88     1 */
	bool                       frozen;               /*    89     1 */

	/* XXX 38 bytes hole, try to pack */

	/* --- cacheline 2 boundary (128 bytes) --- */
	atomic64_t                 refcnt __attribute__((__aligned__(64))); /*   128     8 */
	atomic64_t                 usercnt;              /*   136     8 */
	struct work_struct work;                         /*   144    32 */
	char                       name[16];             /*   176    16 */

	/* size: 192, cachelines: 3, members: 21 */
	/* sum members: 154, holes: 1, sum holes: 38 */
	/* forced alignments: 2, forced holes: 1, sum forced holes: 38 */
} __attribute__((__aligned__(64)));

This patch, while modifying all users of bpf_map_inc, also cleans up its
interface to match bpf_map_put with separate operations for bpf_map_inc and
bpf_map_inc_with_uref (to match bpf_map_put and bpf_map_put_with_uref,
respectively). Also, given there are no users of bpf_map_inc_not_zero
specifying uref=true, remove uref flag and default to uref=false internally.
Signed-off-by: NAndrii Nakryiko <andriin@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191117172806.2195367-2-andriin@fb.com

Allow FENTRY/FEXIT BPF programs to attach to other BPF programs of any type
including their subprograms. This feature allows snooping on input and output
packets in XDP, TC programs including their return values. In order to do that
the verifier needs to track types not only of vmlinux, but types of other BPF
programs as well. The verifier also needs to translate uapi/linux/bpf.h types
used by networking programs into kernel internal BTF types used by FENTRY/FEXIT
BPF programs. In some cases LLVM optimizations can remove arguments from BPF
subprograms without adjusting BTF info that LLVM backend knows. When BTF info
disagrees with actual types that the verifiers sees the BPF trampoline has to
fallback to conservative and treat all arguments as u64. The FENTRY/FEXIT
program can still attach to such subprograms, but it won't be able to recognize
pointer types like 'struct sk_buff *' and it won't be able to pass them to
bpf_skb_output() for dumping packets to user space. The FENTRY/FEXIT program
would need to use bpf_probe_read_kernel() instead.

The BPF_PROG_LOAD command is extended with attach_prog_fd field. When it's set
to zero the attach_btf_id is one vmlinux BTF type ids. When attach_prog_fd
points to previously loaded BPF program the attach_btf_id is BTF type id of
main function or one of its subprograms.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-18-ast@kernel.org

Make the verifier check that BTF types of function arguments match actual types
passed into top-level BPF program and into BPF-to-BPF calls. If types match
such BPF programs and sub-programs will have full support of BPF trampoline. If
types mismatch the trampoline has to be conservative. It has to save/restore
five program arguments and assume 64-bit scalars.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NSong Liu <songliubraving@fb.com>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-17-ast@kernel.org

Annotate BPF program context types with program-side type and kernel-side type.
This type information is used by the verifier. btf_get_prog_ctx_type() is
used in the later patches to verify that BTF type of ctx in BPF program matches to
kernel expected ctx type. For example, the XDP program type is:
BPF_PROG_TYPE(BPF_PROG_TYPE_XDP, xdp, struct xdp_md, struct xdp_buff)
That means that XDP program should be written as:
int xdp_prog(struct xdp_md *ctx) { ... }
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-16-ast@kernel.org

btf_resolve_helper_id() caching logic is a bit racy, since under root the
verifier can verify several programs in parallel. Fix it with READ/WRITE_ONCE.
Fix the type as well, since error is also recorded.

Fixes: a7658e1a ("bpf: Check types of arguments passed into helpers")
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NSong Liu <songliubraving@fb.com>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-15-ast@kernel.org

Introduce BPF trampoline concept to allow kernel code to call into BPF programs
with practically zero overhead.  The trampoline generation logic is
architecture dependent.  It's converting native calling convention into BPF
calling convention.  BPF ISA is 64-bit (even on 32-bit architectures). The
registers R1 to R5 are used to pass arguments into BPF functions. The main BPF
program accepts only single argument "ctx" in R1. Whereas CPU native calling
convention is different. x86-64 is passing first 6 arguments in registers
and the rest on the stack. x86-32 is passing first 3 arguments in registers.
sparc64 is passing first 6 in registers. And so on.

The trampolines between BPF and kernel already exist.  BPF_CALL_x macros in
include/linux/filter.h statically compile trampolines from BPF into kernel
helpers. They convert up to five u64 arguments into kernel C pointers and
integers. On 64-bit architectures this BPF_to_kernel trampolines are nops. On
32-bit architecture they're meaningful.

The opposite job kernel_to_BPF trampolines is done by CAST_TO_U64 macros and
__bpf_trace_##call() shim functions in include/trace/bpf_probe.h. They convert
kernel function arguments into array of u64s that BPF program consumes via
R1=ctx pointer.

This patch set is doing the same job as __bpf_trace_##call() static
trampolines, but dynamically for any kernel function. There are ~22k global
kernel functions that are attachable via nop at function entry. The function
arguments and types are described in BTF.  The job of btf_distill_func_proto()
function is to extract useful information from BTF into "function model" that
architecture dependent trampoline generators will use to generate assembly code
to cast kernel function arguments into array of u64s.  For example the kernel
function eth_type_trans has two pointers. They will be casted to u64 and stored
into stack of generated trampoline. The pointer to that stack space will be
passed into BPF program in R1. On x86-64 such generated trampoline will consume
16 bytes of stack and two stores of %rdi and %rsi into stack. The verifier will
make sure that only two u64 are accessed read-only by BPF program. The verifier
will also recognize the precise type of the pointers being accessed and will
not allow typecasting of the pointer to a different type within BPF program.

The tracing use case in the datacenter demonstrated that certain key kernel
functions have (like tcp_retransmit_skb) have 2 or more kprobes that are always
active.  Other functions have both kprobe and kretprobe.  So it is essential to
keep both kernel code and BPF programs executing at maximum speed. Hence
generated BPF trampoline is re-generated every time new program is attached or
detached to maintain maximum performance.

To avoid the high cost of retpoline the attached BPF programs are called
directly. __bpf_prog_enter/exit() are used to support per-program execution
stats.  In the future this logic will be optimized further by adding support
for bpf_stats_enabled_key inside generated assembly code. Introduction of
preemptible and sleepable BPF programs will completely remove the need to call
to __bpf_prog_enter/exit().

Detach of a BPF program from the trampoline should not fail. To avoid memory
allocation in detach path the half of the page is used as a reserve and flipped
after each attach/detach. 2k bytes is enough to call 40+ BPF programs directly
which is enough for BPF tracing use cases. This limit can be increased in the
future.

BPF_TRACE_FENTRY programs have access to raw kernel function arguments while
BPF_TRACE_FEXIT programs have access to kernel return value as well. Often
kprobe BPF program remembers function arguments in a map while kretprobe
fetches arguments from a map and analyzes them together with return value.
BPF_TRACE_FEXIT accelerates this typical use case.

Recursion prevention for kprobe BPF programs is done via per-cpu
bpf_prog_active counter. In practice that turned out to be a mistake. It
caused programs to randomly skip execution. The tracing tools missed results
they were looking for. Hence BPF trampoline doesn't provide builtin recursion
prevention. It's a job of BPF program itself and will be addressed in the
follow up patches.

BPF trampoline is intended to be used beyond tracing and fentry/fexit use cases
in the future. For example to remove retpoline cost from XDP programs.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Acked-by: NSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-5-ast@kernel.org

Add bpf_arch_text_poke() helper that is used by BPF trampoline logic to patch
nops/calls in kernel text into calls into BPF trampoline and to patch
calls/nops inside BPF programs too.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NSong Liu <songliubraving@fb.com>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-4-ast@kernel.org

Currently passing alignment greater than 4 to bpf_jit_binary_alloc does
not work: in such cases it silently aligns only to 4 bytes.

On s390, in order to load a constant from memory in a large (>512k) BPF
program, one must use lgrl instruction, whose memory operand must be
aligned on an 8-byte boundary.

This patch makes it possible to request 8-byte alignment from
bpf_jit_binary_alloc, and also makes it issue a warning when an
unsupported alignment is requested.
Signed-off-by: NIlya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191115123722.58462-1-iii@linux.ibm.com

Add two new probe_kernel_read_strict() and strncpy_from_unsafe_strict()
helpers which by default alias to the __probe_kernel_read() and the
__strncpy_from_unsafe(), respectively, but can be overridden by archs
which have non-overlapping address ranges for kernel space and user
space in order to bail out with -EFAULT when attempting to probe user
memory including non-canonical user access addresses [0]:

  4-level page tables:
    user-space mem: 0x0000000000000000 - 0x00007fffffffffff
    non-canonical:  0x0000800000000000 - 0xffff7fffffffffff

  5-level page tables:
    user-space mem: 0x0000000000000000 - 0x00ffffffffffffff
    non-canonical:  0x0100000000000000 - 0xfeffffffffffffff

The idea is that these helpers are complementary to the probe_user_read()
and strncpy_from_unsafe_user() which probe user-only memory. Both added
helpers here do the same, but for kernel-only addresses.

Both set of helpers are going to be used for BPF tracing. They also
explicitly avoid throwing the splat for non-canonical user addresses from
00c42373 ("x86-64: add warning for non-canonical user access address
dereferences").

For compat, the current probe_kernel_read() and strncpy_from_unsafe() are
left as-is.

  [0] Documentation/x86/x86_64/mm.txt
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: x86@kernel.org
Link: https://lore.kernel.org/bpf/eefeefd769aa5a013531f491a71f0936779e916b.1572649915.git.daniel@iogearbox.net

Commit 3d708182 ("uaccess: Add non-pagefault user-space read functions")
missed to add probe write function, therefore factor out a probe_write_common()
helper with most logic of probe_kernel_write() except setting KERNEL_DS, and
add a new probe_user_write() helper so it can be used from BPF side.

Again, on some archs, the user address space and kernel address space can
co-exist and be overlapping, so in such case, setting KERNEL_DS would mean
that the given address is treated as being in kernel address space.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/bpf/9df2542e68141bfa3addde631441ee45503856a8.1572649915.git.daniel@iogearbox.net

In this commit the XSKMAP entry lookup function used by the XDP
redirect code is moved from the xskmap.c file to the xdp_sock.h
header, so the lookup can be inlined from, e.g., the
bpf_xdp_redirect_map() function.

Further the __xsk_map_redirect() and __xsk_map_flush() is moved to the
xsk.c, which lets the compiler inline the xsk_rcv() and xsk_flush()
functions.

Finally, all the XDP socket functions were moved from linux/bpf.h to
net/xdp_sock.h, where most of the XDP sockets functions are anyway.

This yields a ~2% performance boost for the xdpsock "rx_drop"
scenario.
Signed-off-by: NBjörn Töpel <bjorn.topel@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191101110346.15004-4-bjorn.topel@gmail.com

Using the newly added fsl_mc_get_endpoint function a fsl-mc driver can
find its associated endpoint (another object at the other link of a MC
firmware link).

The API will be used in the following patch in order to discover the
connected DPMAC object of a DPNI.

Also, the fsl_mc_device_lookup function is made available to the entire
fsl-mc bus driver and not just for the dprc driver.
Signed-off-by: NIoana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SOMAXCONN is /proc/sys/net/core/somaxconn default value.

It has been defined as 128 more than 20 years ago.

Since it caps the listen() backlog values, the very small value has
caused numerous problems over the years, and many people had
to raise it on their hosts after beeing hit by problems.

Google has been using 1024 for at least 15 years, and we increased
this to 4096 after TCP listener rework has been completed, more than
4 years ago. We got no complain of this change breaking any
legacy application.

Many applications indeed setup a TCP listener with listen(fd, -1);
meaning they let the system select the backlog.

Raising SOMAXCONN lowers chance of the port being unavailable under
even small SYNFLOOD attack, and reduces possibilities of side channel
vulnerabilities.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Yue Cao <ycao009@ucr.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This driver registers on TEE bus to interact with OP-TEE based
BNXT firmware management modules

Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Reported-by: Nkbuild test robot <lkp@intel.com>
Signed-off-by: NVikas Gupta <vikas.gupta@broadcom.com>
Signed-off-by: NSheetal Tigadoli <sheetal.tigadoli@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The bpf program type raw_tp together with 'expected_attach_type'
was the most appropriate api to indicate BTF-enabled raw_tp programs.
But during development it became apparent that 'expected_attach_type'
cannot be used and new 'attach_btf_id' field had to be introduced.
Which means that the information is duplicated in two fields where
one of them is ignored.
Clean it up by introducing new program type where both
'expected_attach_type' and 'attach_btf_id' fields have
specific meaning.
In the future 'expected_attach_type' will be extended
with other attach points that have similar semantics to raw_tp.
This patch is replacing BTF-enabled BPF_PROG_TYPE_RAW_TRACEPOINT with
prog_type = BPF_RPOG_TYPE_TRACING
expected_attach_type = BPF_TRACE_RAW_TP
attach_btf_id = btf_id of raw tracepoint inside the kernel
Future patches will add
expected_attach_type = BPF_TRACE_FENTRY or BPF_TRACE_FEXIT
where programs have the same input context and the same helpers,
but different attach points.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAndrii Nakryiko <andriin@fb.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191030223212.953010-2-ast@kernel.org

The driver exposes EFI runtime services to user-space through an IOCTL
interface, calling the EFI services function pointers directly without
using the efivar API.

Disallow access to the /dev/efi_test character device when the kernel is
locked down to prevent arbitrary user-space to call EFI runtime services.

Also require CAP_SYS_ADMIN to open the chardev to prevent unprivileged
users to call the EFI runtime services, instead of just relying on the
chardev file mode bits for this.

The main user of this driver is the fwts [0] tool that already checks if
the effective user ID is 0 and fails otherwise. So this change shouldn't
cause any regression to this tool.

[0]: https://wiki.ubuntu.com/FirmwareTestSuite/Reference/uefivarinfoSigned-off-by: NJavier Martinez Canillas <javierm@redhat.com>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: NLaszlo Ersek <lersek@redhat.com>
Acked-by: NMatthew Garrett <mjg59@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191029173755.27149-7-ardb@kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Currently, kernel fails to boot on some HyperV VMs when using EFI.
And it's a potential issue on all x86 platforms.

It's caused by broken kernel relocation on EFI systems, when below three
conditions are met:

1. Kernel image is not loaded to the default address (LOAD_PHYSICAL_ADDR)
   by the loader.
2. There isn't enough room to contain the kernel, starting from the
   default load address (eg. something else occupied part the region).
3. In the memmap provided by EFI firmware, there is a memory region
   starts below LOAD_PHYSICAL_ADDR, and suitable for containing the
   kernel.

EFI stub will perform a kernel relocation when condition 1 is met. But
due to condition 2, EFI stub can't relocate kernel to the preferred
address, so it fallback to ask EFI firmware to alloc lowest usable memory
region, got the low region mentioned in condition 3, and relocated
kernel there.

It's incorrect to relocate the kernel below LOAD_PHYSICAL_ADDR. This
is the lowest acceptable kernel relocation address.

The first thing goes wrong is in arch/x86/boot/compressed/head_64.S.
Kernel decompression will force use LOAD_PHYSICAL_ADDR as the output
address if kernel is located below it. Then the relocation before
decompression, which move kernel to the end of the decompression buffer,
will overwrite other memory region, as there is no enough memory there.

To fix it, just don't let EFI stub relocate the kernel to any address
lower than lowest acceptable address.

[ ardb: introduce efi_low_alloc_above() to reduce the scope of the change ]
Signed-off-by: NKairui Song <kasong@redhat.com>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: NJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191029173755.27149-6-ardb@kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

When we're destroying the host transport mechanism, we should ensure
that we do not leak memory by failing to release any back channel
slots that might still exist.
Reported-by: NNeil Brown <neilb@suse.de>
Reported-by: Nkbuild test robot <lkp@intel.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

The union should contain the extended dest and counter list.
Remove the resevered 0x40 bits which is redundant.
This change doesn't break any functionally.
Everything works today because the code in fs_cmd.c is using
the correct structs if extended dest or the basic dest.

Fixes: 1b115498 ("net/mlx5: Introduce extended destination fields")
Signed-off-by: NRoi Dayan <roid@mellanox.com>
Reviewed-by: NMark Bloch <markb@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

sk_page_frag() optimizes skb_frag allocations by using per-task
skb_frag cache when it knows it's the only user.  The condition is
determined by seeing whether the socket allocation mask allows
blocking - if the allocation may block, it obviously owns the task's
context and ergo exclusively owns current->task_frag.

Unfortunately, this misses recursion through memory reclaim path.
Please take a look at the following backtrace.

 [2] RIP: 0010:tcp_sendmsg_locked+0xccf/0xe10
     ...
     tcp_sendmsg+0x27/0x40
     sock_sendmsg+0x30/0x40
     sock_xmit.isra.24+0xa1/0x170 [nbd]
     nbd_send_cmd+0x1d2/0x690 [nbd]
     nbd_queue_rq+0x1b5/0x3b0 [nbd]
     __blk_mq_try_issue_directly+0x108/0x1b0
     blk_mq_request_issue_directly+0xbd/0xe0
     blk_mq_try_issue_list_directly+0x41/0xb0
     blk_mq_sched_insert_requests+0xa2/0xe0
     blk_mq_flush_plug_list+0x205/0x2a0
     blk_flush_plug_list+0xc3/0xf0
 [1] blk_finish_plug+0x21/0x2e
     _xfs_buf_ioapply+0x313/0x460
     __xfs_buf_submit+0x67/0x220
     xfs_buf_read_map+0x113/0x1a0
     xfs_trans_read_buf_map+0xbf/0x330
     xfs_btree_read_buf_block.constprop.42+0x95/0xd0
     xfs_btree_lookup_get_block+0x95/0x170
     xfs_btree_lookup+0xcc/0x470
     xfs_bmap_del_extent_real+0x254/0x9a0
     __xfs_bunmapi+0x45c/0xab0
     xfs_bunmapi+0x15/0x30
     xfs_itruncate_extents_flags+0xca/0x250
     xfs_free_eofblocks+0x181/0x1e0
     xfs_fs_destroy_inode+0xa8/0x1b0
     destroy_inode+0x38/0x70
     dispose_list+0x35/0x50
     prune_icache_sb+0x52/0x70
     super_cache_scan+0x120/0x1a0
     do_shrink_slab+0x120/0x290
     shrink_slab+0x216/0x2b0
     shrink_node+0x1b6/0x4a0
     do_try_to_free_pages+0xc6/0x370
     try_to_free_mem_cgroup_pages+0xe3/0x1e0
     try_charge+0x29e/0x790
     mem_cgroup_charge_skmem+0x6a/0x100
     __sk_mem_raise_allocated+0x18e/0x390
     __sk_mem_schedule+0x2a/0x40
 [0] tcp_sendmsg_locked+0x8eb/0xe10
     tcp_sendmsg+0x27/0x40
     sock_sendmsg+0x30/0x40
     ___sys_sendmsg+0x26d/0x2b0
     __sys_sendmsg+0x57/0xa0
     do_syscall_64+0x42/0x100
     entry_SYSCALL_64_after_hwframe+0x44/0xa9

In [0], tcp_send_msg_locked() was using current->page_frag when it
called sk_wmem_schedule().  It already calculated how many bytes can
be fit into current->page_frag.  Due to memory pressure,
sk_wmem_schedule() called into memory reclaim path which called into
xfs and then IO issue path.  Because the filesystem in question is
backed by nbd, the control goes back into the tcp layer - back into
tcp_sendmsg_locked().

nbd sets sk_allocation to (GFP_NOIO | __GFP_MEMALLOC) which makes
sense - it's in the process of freeing memory and wants to be able to,
e.g., drop clean pages to make forward progress.  However, this
confused sk_page_frag() called from [2].  Because it only tests
whether the allocation allows blocking which it does, it now thinks
current->page_frag can be used again although it already was being
used in [0].

After [2] used current->page_frag, the offset would be increased by
the used amount.  When the control returns to [0],
current->page_frag's offset is increased and the previously calculated
number of bytes now may overrun the end of allocated memory leading to
silent memory corruptions.

Fix it by adding gfpflags_normal_context() which tests sleepable &&
!reclaim and use it to determine whether to use current->task_frag.

v2: Eric didn't like gfp flags being tested twice.  Introduce a new
    helper gfpflags_normal_context() and combine the two tests.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some paths call skb_queue_empty() without holding
the queue lock. We must use a barrier in order
to not let the compiler do strange things, and avoid
KCSAN splats.

Adding a barrier in skb_queue_empty() might be overkill,
I prefer adding a new helper to clearly identify
points where the callers might be lockless. This might
help us finding real bugs.

The corresponding WRITE_ONCE() should add zero cost
for current compilers.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As per POSIX, the correct spelling of the error code is EACCES:

  include/uapi/asm-generic/errno-base.h:#define EACCES 13 /* Permission denied */
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/20191024122904.12463-1-geert+renesas@glider.beSigned-off-by: NIngo Molnar <mingo@kernel.org>

The 'work' field was introduced with commit 06a8fc78
("VSOCK: Introduce virtio_vsock_common.ko")
but it is never used in the code, so we can remove it to save
memory allocated in the per-packet 'struct virtio_vsock_pkt'
Suggested-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NStefano Garzarella <sgarzare@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

The TCPI_OPT_SYN_DATA bit as part of tcpi_options currently reports whether
or not data-in-SYN was ack'd on both the client and server side. We'd like
to gather more information on the client-side in the failure case in order
to indicate the reason for the failure. This can be useful for not only
debugging TFO, but also for creating TFO socket policies. For example, if
a middle box removes the TFO option or drops a data-in-SYN, we can
can detect this case, and turn off TFO for these connections saving the
extra retransmits.

The newly added tcpi_fastopen_client_fail status is 2 bits and has the
following 4 states:

1) TFO_STATUS_UNSPEC

Catch-all state which includes when TFO is disabled via black hole
detection, which is indicated via LINUX_MIB_TCPFASTOPENBLACKHOLE.

2) TFO_COOKIE_UNAVAILABLE

If TFO_CLIENT_NO_COOKIE mode is off, this state indicates that no cookie
is available in the cache.

3) TFO_DATA_NOT_ACKED

Data was sent with SYN, we received a SYN/ACK but it did not cover the data
portion. Cookie is not accepted by server because the cookie may be invalid
or the server may be overloaded.

4) TFO_SYN_RETRANSMITTED

Data was sent with SYN, we received a SYN/ACK which did not cover the data
after at least 1 additional SYN was sent (without data). It may be the case
that a middle-box is dropping data-in-SYN packets. Thus, it would be more
efficient to not use TFO on this connection to avoid extra retransmits
during connection establishment.

These new fields do not cover all the cases where TFO may fail, but other
failures, such as SYN/ACK + data being dropped, will result in the
connection not becoming established. And a connection blackhole after
session establishment shows up as a stalled connection.
Signed-off-by: NJason Baron <jbaron@akamai.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Christoph Paasch <cpaasch@apple.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch makes a few changes to btf_ctx_access() to prepare
it for non raw_tp use case where the attach_btf_id is not
necessary a BTF_KIND_TYPEDEF.

It moves the "btf_trace_" prefix check and typedef-follow logic to a new
function "check_attach_btf_id()" which is called only once during
bpf_check().  btf_ctx_access() only operates on a BTF_KIND_FUNC_PROTO
type now. That should also be more efficient since it is done only
one instead of every-time check_ctx_access() is called.

"check_attach_btf_id()" needs to find the func_proto type from
the attach_btf_id.  It needs to store the result into the
newly added prog->aux->attach_func_proto.  func_proto
btf type has no name, so a proper name should be stored into
"attach_func_name" also.

v2:
- Move the "btf_trace_" check to an earlier verifier phase (Alexei)
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191025001811.1718491-1-kafai@fb.com

This patch removes variables and callback these are related to the nested
device structure.
devices that can be nested have their own nest_level variable that
represents the depth of nested devices.
In the previous patch, new {lower/upper}_level variables are added and
they replace old private nest_level variable.
So, this patch removes all 'nest_level' variables.

In order to avoid lockdep warning, ->ndo_get_lock_subclass() was added
to get lockdep subclass value, which is actually lower nested depth value.
But now, they use the dynamic lockdep key to avoid lockdep warning instead
of the subclass.
So, this patch removes ->ndo_get_lock_subclass() callback.
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In order to link an adjacent node, netdev_upper_dev_link() is used
and in order to unlink an adjacent node, netdev_upper_dev_unlink() is used.
unlink operation does not fail, but link operation can fail.

In order to exchange adjacent nodes, we should unlink an old adjacent
node first. then, link a new adjacent node.
If link operation is failed, we should link an old adjacent node again.
But this link operation can fail too.
It eventually breaks the adjacent link relationship.

This patch adds an ignore flag into the netdev_adjacent structure.
If this flag is set, netdev_upper_dev_link() ignores an old adjacent
node for a moment.

This patch also adds new functions for other modules.
netdev_adjacent_change_prepare()
netdev_adjacent_change_commit()
netdev_adjacent_change_abort()

netdev_adjacent_change_prepare() inserts new device into adjacent list
but new device is not allowed to use immediately.
If netdev_adjacent_change_prepare() fails, it internally rollbacks
adjacent list so that we don't need any other action.
netdev_adjacent_change_commit() deletes old device in the adjacent list
and allows new device to use.
netdev_adjacent_change_abort() rollbacks adjacent list.
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

team interface could be nested and it's lock variable could be nested too.
But this lock uses static lockdep key and there is no nested locking
handling code such as mutex_lock_nested() and so on.
so the Lockdep would warn about the circular locking scenario that
couldn't happen.
In order to fix, this patch makes the team module to use dynamic lock key
instead of static key.

Test commands:
    ip link add team0 type team
    ip link add team1 type team
    ip link set team0 master team1
    ip link set team0 nomaster
    ip link set team1 master team0
    ip link set team1 nomaster

Splat that looks like:
[   40.364352] WARNING: possible recursive locking detected
[   40.364964] 5.4.0-rc3+ #96 Not tainted
[   40.365405] --------------------------------------------
[   40.365973] ip/750 is trying to acquire lock:
[   40.366542] ffff888060b34c40 (&team->lock){+.+.}, at: team_set_mac_address+0x151/0x290 [team]
[   40.367689]
	       but task is already holding lock:
[   40.368729] ffff888051201c40 (&team->lock){+.+.}, at: team_del_slave+0x29/0x60 [team]
[   40.370280]
	       other info that might help us debug this:
[   40.371159]  Possible unsafe locking scenario:

[   40.371942]        CPU0
[   40.372338]        ----
[   40.372673]   lock(&team->lock);
[   40.373115]   lock(&team->lock);
[   40.373549]
	       *** DEADLOCK ***

[   40.374432]  May be due to missing lock nesting notation

[   40.375338] 2 locks held by ip/750:
[   40.375851]  #0: ffffffffabcc42b0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x466/0x8a0
[   40.376927]  #1: ffff888051201c40 (&team->lock){+.+.}, at: team_del_slave+0x29/0x60 [team]
[   40.377989]
	       stack backtrace:
[   40.378650] CPU: 0 PID: 750 Comm: ip Not tainted 5.4.0-rc3+ #96
[   40.379368] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   40.380574] Call Trace:
[   40.381208]  dump_stack+0x7c/0xbb
[   40.381959]  __lock_acquire+0x269d/0x3de0
[   40.382817]  ? register_lock_class+0x14d0/0x14d0
[   40.383784]  ? check_chain_key+0x236/0x5d0
[   40.384518]  lock_acquire+0x164/0x3b0
[   40.385074]  ? team_set_mac_address+0x151/0x290 [team]
[   40.385805]  __mutex_lock+0x14d/0x14c0
[   40.386371]  ? team_set_mac_address+0x151/0x290 [team]
[   40.387038]  ? team_set_mac_address+0x151/0x290 [team]
[   40.387632]  ? mutex_lock_io_nested+0x1380/0x1380
[   40.388245]  ? team_del_slave+0x60/0x60 [team]
[   40.388752]  ? rcu_read_lock_sched_held+0x90/0xc0
[   40.389304]  ? rcu_read_lock_bh_held+0xa0/0xa0
[   40.389819]  ? lock_acquire+0x164/0x3b0
[   40.390285]  ? lockdep_rtnl_is_held+0x16/0x20
[   40.390797]  ? team_port_get_rtnl+0x90/0xe0 [team]
[   40.391353]  ? __module_text_address+0x13/0x140
[   40.391886]  ? team_set_mac_address+0x151/0x290 [team]
[   40.392547]  team_set_mac_address+0x151/0x290 [team]
[   40.393111]  dev_set_mac_address+0x1f0/0x3f0
[ ... ]

Fixes: 3d249d4c ("net: introduce ethernet teaming device")
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some interface types could be nested.
(VLAN, BONDING, TEAM, MACSEC, MACVLAN, IPVLAN, VIRT_WIFI, VXLAN, etc..)
These interface types should set lockdep class because, without lockdep
class key, lockdep always warn about unexisting circular locking.

In the current code, these interfaces have their own lockdep class keys and
these manage itself. So that there are so many duplicate code around the
/driver/net and /net/.
This patch adds new generic lockdep keys and some helper functions for it.

This patch does below changes.
a) Add lockdep class keys in struct net_device
   - qdisc_running, xmit, addr_list, qdisc_busylock
   - these keys are used as dynamic lockdep key.
b) When net_device is being allocated, lockdep keys are registered.
   - alloc_netdev_mqs()
c) When net_device is being free'd llockdep keys are unregistered.
   - free_netdev()
d) Add generic lockdep key helper function
   - netdev_register_lockdep_key()
   - netdev_unregister_lockdep_key()
   - netdev_update_lockdep_key()
e) Remove unnecessary generic lockdep macro and functions
f) Remove unnecessary lockdep code of each interfaces.

After this patch, each interface modules don't need to maintain
their lockdep keys.
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Current code doesn't limit the number of nested devices.
Nested devices would be handled recursively and this needs huge stack
memory. So, unlimited nested devices could make stack overflow.

This patch adds upper_level and lower_level, they are common variables
and represent maximum lower/upper depth.
When upper/lower device is attached or dettached,
{lower/upper}_level are updated. and if maximum depth is bigger than 8,
attach routine fails and returns -EMLINK.

In addition, this patch converts recursive routine of
netdev_walk_all_{lower/upper} to iterator routine.

Test commands:
    ip link add dummy0 type dummy
    ip link add link dummy0 name vlan1 type vlan id 1
    ip link set vlan1 up

    for i in {2..55}
    do
	    let A=$i-1

	    ip link add vlan$i link vlan$A type vlan id $i
    done
    ip link del dummy0

Splat looks like:
[  155.513226][  T908] BUG: KASAN: use-after-free in __unwind_start+0x71/0x850
[  155.514162][  T908] Write of size 88 at addr ffff8880608a6cc0 by task ip/908
[  155.515048][  T908]
[  155.515333][  T908] CPU: 0 PID: 908 Comm: ip Not tainted 5.4.0-rc3+ #96
[  155.516147][  T908] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  155.517233][  T908] Call Trace:
[  155.517627][  T908]
[  155.517918][  T908] Allocated by task 0:
[  155.518412][  T908] (stack is not available)
[  155.518955][  T908]
[  155.519228][  T908] Freed by task 0:
[  155.519885][  T908] (stack is not available)
[  155.520452][  T908]
[  155.520729][  T908] The buggy address belongs to the object at ffff8880608a6ac0
[  155.520729][  T908]  which belongs to the cache names_cache of size 4096
[  155.522387][  T908] The buggy address is located 512 bytes inside of
[  155.522387][  T908]  4096-byte region [ffff8880608a6ac0, ffff8880608a7ac0)
[  155.523920][  T908] The buggy address belongs to the page:
[  155.524552][  T908] page:ffffea0001822800 refcount:1 mapcount:0 mapping:ffff88806c657cc0 index:0x0 compound_mapcount:0
[  155.525836][  T908] flags: 0x100000000010200(slab|head)
[  155.526445][  T908] raw: 0100000000010200 ffffea0001813808 ffffea0001a26c08 ffff88806c657cc0
[  155.527424][  T908] raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
[  155.528429][  T908] page dumped because: kasan: bad access detected
[  155.529158][  T908]
[  155.529410][  T908] Memory state around the buggy address:
[  155.530060][  T908]  ffff8880608a6b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  155.530971][  T908]  ffff8880608a6c00: fb fb fb fb fb f1 f1 f1 f1 00 f2 f2 f2 f3 f3 f3
[  155.531889][  T908] >ffff8880608a6c80: f3 fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  155.532806][  T908]                                            ^
[  155.533509][  T908]  ffff8880608a6d00: fb fb fb fb fb fb fb fb fb f1 f1 f1 f1 00 00 00
[  155.534436][  T908]  ffff8880608a6d80: f2 f3 f3 f3 f3 fb fb fb 00 00 00 00 00 00 00 00
[ ... ]
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The BCM54616S PHY cannot work properly in RGMII->1000Base-X mode, mainly
because genphy functions are designed for copper links, and 1000Base-X
(clause 37) auto negotiation needs to be handled differently.

This patch enables 1000Base-X support for BCM54616S by customizing 3
driver callbacks, and it's verified to be working on Facebook CMM BMC
platform (RGMII->1000Base-KX):

  - probe: probe callback detects PHY's operation mode based on
    INTERF_SEL[1:0] pins and 1000X/100FX selection bit in SerDES 100-FX
    Control register.

  - config_aneg: calls genphy_c37_config_aneg when the PHY is running in
    1000Base-X mode; otherwise, genphy_config_aneg will be called.

  - read_status: calls genphy_c37_read_status when the PHY is running in
    1000Base-X mode; otherwise, genphy_read_status will be called.

Note: BCM54616S PHY can also be configured in RGMII->100Base-FX mode, and
100Base-FX support is not available as of now.
Signed-off-by: NTao Ren <taoren@fb.com>
Acked-by: NVladimir Oltean <olteanv@gmail.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds support for clause 37 1000Base-X auto-negotiation.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NTao Ren <taoren@fb.com>
Tested-by: NRené van Dorst <opensource@vdorst.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

UDP IPv6 packets auto flowlabels are using a 32bit secret
(static u32 hashrnd in net/core/flow_dissector.c) and
apply jhash() over fields known by the receivers.

Attackers can easily infer the 32bit secret and use this information
to identify a device and/or user, since this 32bit secret is only
set at boot time.

Really, using jhash() to generate cookies sent on the wire
is a serious security concern.

Trying to change the rol32(hash, 16) in ip6_make_flowlabel() would be
a dead end. Trying to periodically change the secret (like in sch_sfq.c)
could change paths taken in the network for long lived flows.

Let's switch to siphash, as we did in commit df453700
("inet: switch IP ID generator to siphash")

Using a cryptographically strong pseudo random function will solve this
privacy issue and more generally remove other weak points in the stack.

Packet schedulers using skb_get_hash_perturb() benefit from this change.

Fixes: b5677416 ("ipv6: Enable auto flow labels by default")
Fixes: 42240901 ("ipv6: Implement different admin modes for automatic flow labels")
Fixes: 67800f9b ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel")
Fixes: cb1ce2ef ("ipv6: Implement automatic flow label generation on transmit")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NJonathan Berger <jonathann1@walla.com>
Reported-by: NAmit Klein <aksecurity@gmail.com>
Reported-by: NBenny Pinkas <benny@pinkas.net>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ionic driver started using dymamic_hex_dump(), but
that is not always defined:

drivers/net/ethernet/pensando/ionic/ionic_main.c:229:2: error: implicit declaration of function 'dynamic_hex_dump' [-Werror,-Wimplicit-function-declaration]

Add a dummy implementation to use when CONFIG_DYNAMIC_DEBUG
is disabled, printing nothing.

Fixes: 938962d5 ("ionic: Add adminq action")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NShannon Nelson <snelson@pensando.io>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

syzkaller managed to trigger the following crash:

  [...]
  BUG: unable to handle page fault for address: ffffc90001923030
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD aa551067 P4D aa551067 PUD aa552067 PMD a572b067 PTE 80000000a1173163
  Oops: 0000 [#1] PREEMPT SMP KASAN
  CPU: 0 PID: 7982 Comm: syz-executor912 Not tainted 5.4.0-rc3+ #0
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
  RIP: 0010:bpf_jit_binary_hdr include/linux/filter.h:787 [inline]
  RIP: 0010:bpf_get_prog_addr_region kernel/bpf/core.c:531 [inline]
  RIP: 0010:bpf_tree_comp kernel/bpf/core.c:600 [inline]
  RIP: 0010:__lt_find include/linux/rbtree_latch.h:115 [inline]
  RIP: 0010:latch_tree_find include/linux/rbtree_latch.h:208 [inline]
  RIP: 0010:bpf_prog_kallsyms_find kernel/bpf/core.c:674 [inline]
  RIP: 0010:is_bpf_text_address+0x184/0x3b0 kernel/bpf/core.c:709
  [...]
  Call Trace:
   kernel_text_address kernel/extable.c:147 [inline]
   __kernel_text_address+0x9a/0x110 kernel/extable.c:102
   unwind_get_return_address+0x4c/0x90 arch/x86/kernel/unwind_frame.c:19
   arch_stack_walk+0x98/0xe0 arch/x86/kernel/stacktrace.c:26
   stack_trace_save+0xb6/0x150 kernel/stacktrace.c:123
   save_stack mm/kasan/common.c:69 [inline]
   set_track mm/kasan/common.c:77 [inline]
   __kasan_kmalloc+0x11c/0x1b0 mm/kasan/common.c:510
   kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:518
   slab_post_alloc_hook mm/slab.h:584 [inline]
   slab_alloc mm/slab.c:3319 [inline]
   kmem_cache_alloc+0x1f5/0x2e0 mm/slab.c:3483
   getname_flags+0xba/0x640 fs/namei.c:138
   getname+0x19/0x20 fs/namei.c:209
   do_sys_open+0x261/0x560 fs/open.c:1091
   __do_sys_open fs/open.c:1115 [inline]
   __se_sys_open fs/open.c:1110 [inline]
   __x64_sys_open+0x87/0x90 fs/open.c:1110
   do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:290
   entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [...]

After further debugging it turns out that we walk kallsyms while in parallel
we tear down a BPF program which contains subprograms that have been JITed
though the program itself has not been fully exposed and is eventually bailing
out with error.

The bpf_prog_kallsyms_del_subprogs() in bpf_prog_load()'s error path removes
the symbols, however, bpf_prog_free() tears down the JIT memory too early via
scheduled work. Instead, it needs to properly respect RCU grace period as the
kallsyms walk for BPF is under RCU.

Fix it by refactoring __bpf_prog_put()'s tear down and reuse it in our error
path where we defer final destruction when we have subprogs in the program.

Fixes: 7d1982b4 ("bpf: fix panic in prog load calls cleanup")
Fixes: 1c2a088a ("bpf: x64: add JIT support for multi-function programs")
Reported-by: syzbot+710043c5d1d5b5013bc7@syzkaller.appspotmail.com
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Tested-by: syzbot+710043c5d1d5b5013bc7@syzkaller.appspotmail.com
Link: https://lore.kernel.org/bpf/55f6367324c2d7e9583fa9ccf5385dcbba0d7a6e.1571752452.git.daniel@iogearbox.net

There are no more active users of DEV_PM_QOS_MIN_FREQUENCY and
DEV_PM_QOS_MAX_FREQUENCY device PM QoS request types, so drop them
along with the code supporting them.
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>