This work adds a bpf_skb_change_tail() helper for tc BPF programs. The
basic idea is to expand or shrink the skb in a controlled manner. The
eBPF program can then rewrite the rest via helpers like bpf_skb_store_bytes(),
bpf_lX_csum_replace() and others rather than passing a raw buffer for
writing here.
bpf_skb_change_tail() is really a slow path helper and intended for
replies with f.e. ICMP control messages. Concept is similar to other
helpers like bpf_skb_change_proto() helper to keep the helper without
protocol specifics and let the BPF program mangle the remaining parts.
A flags field has been added and is reserved for now should we extend
the helper in future.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Add a new bpf prog type that is intended to run in early stages of the
packet rx path. Only minimal packet metadata will be available, hence a
new context type, struct xdp_md, is exposed to userspace. So far only
expose the packet start and end pointers, and only in read mode.
An XDP program must return one of the well known enum values, all other
return codes are reserved for future use. Unfortunately, this
restriction is hard to enforce at verification time, so take the
approach of warning at runtime when such programs are encountered. Out
of bounds return codes should alias to XDP_ABORTED.
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
allow cls_bpf and act_bpf programs access skb->data and skb->data_end pointers.
The bpf helpers that change skb->data need to update data_end pointer as well.
The verifier checks that programs always reload data, data_end pointers
after calls to such bpf helpers.
We cannot add 'data_end' pointer to struct qdisc_skb_cb directly,
since it's embedded as-is by infiniband ipoib, so wrapper struct is needed.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Move the details behind the cb[] access into a small helper to decouple
and make them generic for bpf_prog_run_save_cb()/bpf_prog_run_clear_cb()
that was introduced via commit ff936a04e5 ("bpf: fix cb access in socket
filter programs"). Also add a comment to better clarify what is done in
bpf_skb_cb().
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
A subsystem may need to store many copies of a bpf program, each
deserving its own reference. Rather than requiring the caller to loop
one by one (with possible mid-loop failure), add a bulk bpf_prog_add
api.
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
This work addresses a couple of issues bpf_skb_event_output()
helper currently has: i) We need two copies instead of just a
single one for the skb data when it should be part of a sample.
The data can be non-linear and thus needs to be extracted via
bpf_skb_load_bytes() helper first, and then copied once again
into the ring buffer slot. ii) Since bpf_skb_load_bytes()
currently needs to be used first, the helper needs to see a
constant size on the passed stack buffer to make sure BPF
verifier can do sanity checks on it during verification time.
Thus, just passing skb->len (or any other non-constant value)
wouldn't work, but changing bpf_skb_load_bytes() is also not
the proper solution, since the two copies are generally still
needed. iii) bpf_skb_load_bytes() is just for rather small
buffers like headers, since they need to sit on the limited
BPF stack anyway. Instead of working around in bpf_skb_load_bytes(),
this work improves the bpf_skb_event_output() helper to address
all 3 at once.
We can make use of the passed in skb context that we have in
the helper anyway, and use some of the reserved flag bits as
a length argument. The helper will use the new __output_custom()
facility from perf side with bpf_skb_copy() as callback helper
to walk and extract the data. It will pass the data for setup
to bpf_event_output(), which generates and pushes the raw record
with an additional frag part. The linear data used in the first
frag of the record serves as programmatically defined meta data
passed along with the appended sample.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Since bpf_prog_get() and program type check is used in a couple of places,
refactor this into a small helper function that we can make use of. Since
the non RO prog->aux part is not used in performance critical paths and a
program destruction via RCU is rather very unlikley when doing the put, we
shouldn't have an issue just doing the bpf_prog_get() + prog->type != type
check, but actually not taking the ref at all (due to being in fdget() /
fdput() section of the bpf fd) is even cleaner and makes the diff smaller
as well, so just go for that. Callsites are changed to make use of the new
helper where possible.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Jann Horn reported following analysis that could potentially result
in a very hard to trigger (if not impossible) UAF race, to quote his
event timeline:
- Set up a process with threads T1, T2 and T3
- Let T1 set up a socket filter F1 that invokes another filter F2
through a BPF map [tail call]
- Let T1 trigger the socket filter via a unix domain socket write,
don't wait for completion
- Let T2 call PERF_EVENT_IOC_SET_BPF with F2, don't wait for completion
- Now T2 should be behind bpf_prog_get(), but before bpf_prog_put()
- Let T3 close the file descriptor for F2, dropping the reference
count of F2 to 2
- At this point, T1 should have looked up F2 from the map, but not
finished executing it
- Let T3 remove F2 from the BPF map, dropping the reference count of
F2 to 1
- Now T2 should call bpf_prog_put() (wrong BPF program type), dropping
the reference count of F2 to 0 and scheduling bpf_prog_free_deferred()
via schedule_work()
- At this point, the BPF program could be freed
- BPF execution is still running in a freed BPF program
While at PERF_EVENT_IOC_SET_BPF time it's only guaranteed that the perf
event fd we're doing the syscall on doesn't disappear from underneath us
for whole syscall time, it may not be the case for the bpf fd used as
an argument only after we did the put. It needs to be a valid fd pointing
to a BPF program at the time of the call to make the bpf_prog_get() and
while T2 gets preempted, F2 must have dropped reference to 1 on the other
CPU. The fput() from the close() in T3 should also add additionally delay
to the reference drop via exit_task_work() when bpf_prog_release() gets
called as well as scheduling bpf_prog_free_deferred().
That said, it makes nevertheless sense to move the BPF prog destruction
generally after RCU grace period to guarantee that such scenario above,
but also others as recently fixed in ceb56070359b ("bpf, perf: delay release
of BPF prog after grace period") with regards to tail calls won't happen.
Integrating bpf_prog_free_deferred() directly into the RCU callback is
not allowed since the invocation might happen from either softirq or
process context, so we're not permitted to block. Reviewing all bpf_prog_put()
invocations from eBPF side (note, cBPF -> eBPF progs don't use this for
their destruction) with call_rcu() look good to me.
Since we don't know whether at the time of attaching the program, we're
already part of a tail call map, we need to use RCU variant. However, due
to this, there won't be severely more stress on the RCU callback queue:
situations with above bpf_prog_get() and bpf_prog_put() combo in practice
normally won't lead to releases, but even if they would, enough effort/
cycles have to be put into loading a BPF program into the kernel already.
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
The behavior of perf event arrays are quite different from all
others as they are tightly coupled to perf event fds, f.e. shown
recently by commit e03e7ee34fdd ("perf/bpf: Convert perf_event_array
to use struct file") to make refcounting on perf event more robust.
A remaining issue that the current code still has is that since
additions to the perf event array take a reference on the struct
file via perf_event_get() and are only released via fput() (that
cleans up the perf event eventually via perf_event_release_kernel())
when the element is either manually removed from the map from user
space or automatically when the last reference on the perf event
map is dropped. However, this leads us to dangling struct file's
when the map gets pinned after the application owning the perf
event descriptor exits, and since the struct file reference will
in such case only be manually dropped or via pinned file removal,
it leads to the perf event living longer than necessary, consuming
needlessly resources for that time.
Relations between perf event fds and bpf perf event map fds can be
rather complex. F.e. maps can act as demuxers among different perf
event fds that can possibly be owned by different threads and based
on the index selection from the program, events get dispatched to
one of the per-cpu fd endpoints. One perf event fd (or, rather a
per-cpu set of them) can also live in multiple perf event maps at
the same time, listening for events. Also, another requirement is
that perf event fds can get closed from application side after they
have been attached to the perf event map, so that on exit perf event
map will take care of dropping their references eventually. Likewise,
when such maps are pinned, the intended behavior is that a user
application does bpf_obj_get(), puts its fds in there and on exit
when fd is released, they are dropped from the map again, so the map
acts rather as connector endpoint. This also makes perf event maps
inherently different from program arrays as described in more detail
in commit c9da161c65 ("bpf: fix clearing on persistent program
array maps").
To tackle this, map entries are marked by the map struct file that
added the element to the map. And when the last reference to that map
struct file is released from user space, then the tracked entries
are purged from the map. This is okay, because new map struct files
instances resp. frontends to the anon inode are provided via
bpf_map_new_fd() that is called when we invoke bpf_obj_get_user()
for retrieving a pinned map, but also when an initial instance is
created via map_create(). The rest is resolved by the vfs layer
automatically for us by keeping reference count on the map's struct
file. Any concurrent updates on the map slot are fine as well, it
just means that perf_event_fd_array_release() needs to delete less
of its own entires.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
This patch extends map_fd_get_ptr() callback that is used by fd array
maps, so that struct file pointer from the related map can be passed
in. It's safe to remove map_update_elem() callback for the two maps since
this is only allowed from syscall side, but not from eBPF programs for these
two map types. Like in per-cpu map case, bpf_fd_array_map_update_elem()
needs to be called directly here due to the extra argument.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Add a release callback for maps that is invoked when the last
reference to its struct file is gone and the struct file about
to be released by vfs. The handler will be used by fd array maps.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
The ctx structure passed into bpf programs is different depending on bpf
program type. The verifier incorrectly marked ctx->data and ctx->data_end
access based on ctx offset only. That caused loads in tracing programs
int bpf_prog(struct pt_regs *ctx) { .. ctx->ax .. }
to be incorrectly marked as PTR_TO_PACKET which later caused verifier
to reject the program that was actually valid in tracing context.
Fix this by doing program type specific matching of ctx offsets.
Fixes: 969bf05eb3ce ("bpf: direct packet access")
Reported-by: Sasha Goldshtein <goldshtn@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
This work adds a generic facility for use from eBPF JIT compilers
that allows for further hardening of JIT generated images through
blinding constants. In response to the original work on BPF JIT
spraying published by Keegan McAllister [1], most BPF JITs were
changed to make images read-only and start at a randomized offset
in the page, where the rest was filled with trap instructions. We
have this nowadays in x86, arm, arm64 and s390 JIT compilers.
Additionally, later work also made eBPF interpreter images read
only for kernels supporting DEBUG_SET_MODULE_RONX, that is, x86,
arm, arm64 and s390 archs as well currently. This is done by
default for mentioned JITs when JITing is enabled. Furthermore,
we had a generic and configurable constant blinding facility on our
todo for quite some time now to further make spraying harder, and
first implementation since around netconf 2016.
We found that for systems where untrusted users can load cBPF/eBPF
code where JIT is enabled, start offset randomization helps a bit
to make jumps into crafted payload harder, but in case where larger
programs that cross page boundary are injected, we again have some
part of the program opcodes at a page start offset. With improved
guessing and more reliable payload injection, chances can increase
to jump into such payload. Elena Reshetova recently wrote a test
case for it [2, 3]. Moreover, eBPF comes with 64 bit constants, which
can leave some more room for payloads. Note that for all this,
additional bugs in the kernel are still required to make the jump
(and of course to guess right, to not jump into a trap) and naturally
the JIT must be enabled, which is disabled by default.
For helping mitigation, the general idea is to provide an option
bpf_jit_harden that admins can tweak along with bpf_jit_enable, so
that for cases where JIT should be enabled for performance reasons,
the generated image can be further hardened with blinding constants
for unpriviledged users (bpf_jit_harden == 1), with trading off
performance for these, but not for privileged ones. We also added
the option of blinding for all users (bpf_jit_harden == 2), which
is quite helpful for testing f.e. with test_bpf.ko. There are no
further e.g. hardening levels of bpf_jit_harden switch intended,
rationale is to have it dead simple to use as on/off. Since this
functionality would need to be duplicated over and over for JIT
compilers to use, which are already complex enough, we provide a
generic eBPF byte-code level based blinding implementation, which is
then just transparently JITed. JIT compilers need to make only a few
changes to integrate this facility and can be migrated one by one.
This option is for eBPF JITs and will be used in x86, arm64, s390
without too much effort, and soon ppc64 JITs, thus that native eBPF
can be blinded as well as cBPF to eBPF migrations, so that both can
be covered with a single implementation. The rule for JITs is that
bpf_jit_blind_constants() must be called from bpf_int_jit_compile(),
and in case blinding is disabled, we follow normally with JITing the
passed program. In case blinding is enabled and we fail during the
process of blinding itself, we must return with the interpreter.
Similarly, in case the JITing process after the blinding failed, we
return normally to the interpreter with the non-blinded code. Meaning,
interpreter doesn't change in any way and operates on eBPF code as
usual. For doing this pre-JIT blinding step, we need to make use of
a helper/auxiliary register, here BPF_REG_AX. This is strictly internal
to the JIT and not in any way part of the eBPF architecture. Just like
in the same way as JITs internally make use of some helper registers
when emitting code, only that here the helper register is one
abstraction level higher in eBPF bytecode, but nevertheless in JIT
phase. That helper register is needed since f.e. manually written
program can issue loads to all registers of eBPF architecture.
The core concept with the additional register is: blind out all 32
and 64 bit constants by converting BPF_K based instructions into a
small sequence from K_VAL into ((RND ^ K_VAL) ^ RND). Therefore, this
is transformed into: BPF_REG_AX := (RND ^ K_VAL), BPF_REG_AX ^= RND,
and REG <OP> BPF_REG_AX, so actual operation on the target register
is translated from BPF_K into BPF_X one that is operating on
BPF_REG_AX's content. During rewriting phase when blinding, RND is
newly generated via prandom_u32() for each processed instruction.
64 bit loads are split into two 32 bit loads to make translation and
patching not too complex. Only basic thing required by JITs is to
call the helper bpf_jit_blind_constants()/bpf_jit_prog_release_other()
pair, and to map BPF_REG_AX into an unused register.
Small bpf_jit_disasm extract from [2] when applied to x86 JIT:
echo 0 > /proc/sys/net/core/bpf_jit_harden
ffffffffa034f5e9 + <x>:
[...]
39: mov $0xa8909090,%eax
3e: mov $0xa8909090,%eax
43: mov $0xa8ff3148,%eax
48: mov $0xa89081b4,%eax
4d: mov $0xa8900bb0,%eax
52: mov $0xa810e0c1,%eax
57: mov $0xa8908eb4,%eax
5c: mov $0xa89020b0,%eax
[...]
echo 1 > /proc/sys/net/core/bpf_jit_harden
ffffffffa034f1e5 + <x>:
[...]
39: mov $0xe1192563,%r10d
3f: xor $0x4989b5f3,%r10d
46: mov %r10d,%eax
49: mov $0xb8296d93,%r10d
4f: xor $0x10b9fd03,%r10d
56: mov %r10d,%eax
59: mov $0x8c381146,%r10d
5f: xor $0x24c7200e,%r10d
66: mov %r10d,%eax
69: mov $0xeb2a830e,%r10d
6f: xor $0x43ba02ba,%r10d
76: mov %r10d,%eax
79: mov $0xd9730af,%r10d
7f: xor $0xa5073b1f,%r10d
86: mov %r10d,%eax
89: mov $0x9a45662b,%r10d
8f: xor $0x325586ea,%r10d
96: mov %r10d,%eax
[...]
As can be seen, original constants that carry payload are hidden
when enabled, actual operations are transformed from constant-based
to register-based ones, making jumps into constants ineffective.
Above extract/example uses single BPF load instruction over and
over, but of course all instructions with constants are blinded.
Performance wise, JIT with blinding performs a bit slower than just
JIT and faster than interpreter case. This is expected, since we
still get all the performance benefits from JITing and in normal
use-cases not every single instruction needs to be blinded. Summing
up all 296 test cases averaged over multiple runs from test_bpf.ko
suite, interpreter was 55% slower than JIT only and JIT with blinding
was 8% slower than JIT only. Since there are also some extremes in
the test suite, I expect for ordinary workloads that the performance
for the JIT with blinding case is even closer to JIT only case,
f.e. nmap test case from suite has averaged timings in ns 29 (JIT),
35 (+ blinding), and 151 (interpreter).
BPF test suite, seccomp test suite, eBPF sample code and various
bigger networking eBPF programs have been tested with this and were
running fine. For testing purposes, I also adapted interpreter and
redirected blinded eBPF image to interpreter and also here all tests
pass.
[1] http://mainisusuallyafunction.blogspot.com/2012/11/attacking-hardened-linux-systems-with.html
[2] https://github.com/01org/jit-spray-poc-for-ksp/
[3] http://www.openwall.com/lists/kernel-hardening/2016/05/03/5
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Elena Reshetova <elena.reshetova@intel.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Move the bpf_jit_enable declaration to the filter.h file where
most other core code is declared, also since we're going to add
a second knob there.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Since the blinding is strictly only called from inside eBPF JITs,
we need to change signatures for bpf_int_jit_compile() and
bpf_prog_select_runtime() first in order to prepare that the
eBPF program we're dealing with can change underneath. Hence,
for call sites, we need to return the latest prog. No functional
change in this patch.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Move the functionality to patch instructions out of the verifier
code and into the core as the new bpf_patch_insn_single() helper
will be needed later on for blinding as well. No changes in
functionality.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
On a system with >32Gbyte of phyiscal memory and infinite RLIMIT_MEMLOCK,
the malicious application may overflow 32-bit bpf program refcnt.
It's also possible to overflow map refcnt on 1Tb system.
Impose 32k hard limit which means that the same bpf program or
map cannot be shared by more than 32k processes.
Fixes: 1be7f75d16 ("bpf: enable non-root eBPF programs")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
The default remains 127, which is good for most cases, and not even hit
most of the time, but then for some cases, as reported by Brendan, 1024+
deep frames are appearing on the radar for things like groovy, ruby.
And in some workloads putting a _lower_ cap on this may make sense. One
that is per event still needs to be put in place tho.
The new file is:
# cat /proc/sys/kernel/perf_event_max_stack
127
Chaging it:
# echo 256 > /proc/sys/kernel/perf_event_max_stack
# cat /proc/sys/kernel/perf_event_max_stack
256
But as soon as there is some event using callchains we get:
# echo 512 > /proc/sys/kernel/perf_event_max_stack
-bash: echo: write error: Device or resource busy
#
Because we only allocate the callchain percpu data structures when there
is a user, which allows for changing the max easily, its just a matter
of having no callchain users at that point.
Reported-and-Tested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/20160426002928.GB16708@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Change-Id: Ic34ecdb4cc1e61257a2926062aa23c960dbd3b8f
. avoid walking the stack when there is no room left in the buffer
. generalize get_perf_callchain() to be called from bpf helper
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
This patch adds a new helper for cls/act programs that can push events
to user space applications. For networking, this can be f.e. for sampling,
debugging, logging purposes or pushing of arbitrary wake-up events. The
idea is similar to a43eec3042 ("bpf: introduce bpf_perf_event_output()
helper") and 39111695b1 ("samples: bpf: add bpf_perf_event_output example").
The eBPF program utilizes a perf event array map that user space populates
with fds from perf_event_open(), the eBPF program calls into the helper
f.e. as skb_event_output(skb, &my_map, BPF_F_CURRENT_CPU, raw, sizeof(raw))
so that the raw data is pushed into the fd f.e. at the map index of the
current CPU.
User space can poll/mmap/etc on this and has a data channel for receiving
events that can be post-processed. The nice thing is that since the eBPF
program and user space application making use of it are tightly coupled,
they can define their own arbitrary raw data format and what/when they
want to push.
While f.e. packet headers could be one part of the meta data that is being
pushed, this is not a substitute for things like packet sockets as whole
packet is not being pushed and push is only done in a single direction.
Intention is more of a generically usable, efficient event pipe to applications.
Workflow is that tc can pin the map and applications can attach themselves
e.g. after cls/act setup to one or multiple map slots, demuxing is done by
the eBPF program.
Adding this facility is with minimal effort, it reuses the helper
introduced in a43eec3042 ("bpf: introduce bpf_perf_event_output() helper")
and we get its functionality for free by overloading its BPF_FUNC_ identifier
for cls/act programs, ctx is currently unused, but will be made use of in
future. Example will be added to iproute2's BPF example files.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
This reverts commit 5a5abb1fa3b05dd ("tun, bpf: fix suspicious RCU usage
in tun_{attach, detach}_filter") and replaces it to use lock_sock around
sk_{attach,detach}_filter. The checks inside filter.c are updated with
lockdep_sock_is_held to check for proper socket locks.
It keeps the code cleaner by ensuring that only one lock governs the
socket filter instead of two independent locks.
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
When passing buffers from eBPF stack space into a helper function, we have
ARG_PTR_TO_STACK argument type for helpers available. The verifier makes sure
that such buffers are initialized, within boundaries, etc.
However, the downside with this is that we have a couple of helper functions
such as bpf_skb_load_bytes() that fill out the passed buffer in the expected
success case anyway, so zero initializing them prior to the helper call is
unneeded/wasted instructions in the eBPF program that can be avoided.
Therefore, add a new helper function argument type called ARG_PTR_TO_RAW_STACK.
The idea is to skip the STACK_MISC check in check_stack_boundary() and color
the related stack slots as STACK_MISC after we checked all call arguments.
Helper functions using ARG_PTR_TO_RAW_STACK must make sure that every path of
the helper function will fill the provided buffer area, so that we cannot leak
any uninitialized stack memory. This f.e. means that error paths need to
memset() the buffers, but the expected fast-path doesn't have to do this
anymore.
Since there's no such helper needing more than at most one ARG_PTR_TO_RAW_STACK
argument, we can keep it simple and don't need to check for multiple areas.
Should in future such a use-case really appear, we have check_raw_mode() that
will make sure we implement support for it first.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
during bpf program loading remember the last byte of ctx access
and at the time of attaching the program to tracepoint check that
the program doesn't access bytes beyond defined in tracepoint fields
This also disallows access to __dynamic_array fields, but can be
relaxed in the future.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
needs two wrapper functions to fetch 'struct pt_regs *' to convert
tracepoint bpf context into kprobe bpf context to reuse existing
helper functions
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
split allows to move expensive update of 'struct trace_entry' to later phase.
Repurpose unused 1st argument of perf_tp_event() to indicate event type.
While splitting use temp variable 'rctx' instead of '*rctx' to avoid
unnecessary loads done by the compiler due to -fno-strict-aliasing
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
It was observed that calling bpf_get_stackid() from a kprobe inside
slub or from spin_unlock causes similar deadlock as with hashmap,
therefore convert stackmap to use pre-allocated memory.
The call_rcu is no longer feasible mechanism, since delayed freeing
causes bpf_get_stackid() to fail unpredictably when number of actual
stacks is significantly less than user requested max_entries.
Since elements are no longer freed into slub, we can push elements into
freelist immediately and let them be recycled.
However the very unlikley race between user space map_lookup() and
program-side recycling is possible:
cpu0 cpu1
---- ----
user does lookup(stackidX)
starts copying ips into buffer
delete(stackidX)
calls bpf_get_stackid()
which recyles the element and
overwrites with new stack trace
To avoid user space seeing a partial stack trace consisting of two
merged stack traces, do bucket = xchg(, NULL); copy; xchg(,bucket);
to preserve consistent stack trace delivery to user space.
Now we can move memset(,0) of left-over element value from critical
path of bpf_get_stackid() into slow-path of user space lookup.
Also disallow lookup() from bpf program, since it's useless and
program shouldn't be messing with collected stack trace.
Note that similar race between user space lookup and kernel side updates
is also present in hashmap, but it's not a new race. bpf programs were
always allowed to modify hash and array map elements while user space
is copying them.
Fixes: d5a3b1f69186 ("bpf: introduce BPF_MAP_TYPE_STACK_TRACE")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
If kprobe is placed on spin_unlock then calling kmalloc/kfree from
bpf programs is not safe, since the following dead lock is possible:
kfree->spin_lock(kmem_cache_node->lock)...spin_unlock->kprobe->
bpf_prog->map_update->kmalloc->spin_lock(of the same kmem_cache_node->lock)
and deadlocks.
The following solutions were considered and some implemented, but
eventually discarded
- kmem_cache_create for every map
- add recursion check to slow-path of slub
- use reserved memory in bpf_map_update for in_irq or in preempt_disabled
- kmalloc via irq_work
At the end pre-allocation of all map elements turned out to be the simplest
solution and since the user is charged upfront for all the memory, such
pre-allocation doesn't affect the user space visible behavior.
Since it's impossible to tell whether kprobe is triggered in a safe
location from kmalloc point of view, use pre-allocation by default
and introduce new BPF_F_NO_PREALLOC flag.
While testing of per-cpu hash maps it was discovered
that alloc_percpu(GFP_ATOMIC) has odd corner cases and often
fails to allocate memory even when 90% of it is free.
The pre-allocation of per-cpu hash elements solves this problem as well.
Turned out that bpf_map_update() quickly followed by
bpf_map_lookup()+bpf_map_delete() is very common pattern used
in many of iovisor/bcc/tools, so there is additional benefit of
pre-allocation, since such use cases are must faster.
Since all hash map elements are now pre-allocated we can remove
atomic increment of htab->count and save few more cycles.
Also add bpf_map_precharge_memlock() to check rlimit_memlock early to avoid
large malloc/free done by users who don't have sufficient limits.
Pre-allocation is done with vmalloc and alloc/free is done
via percpu_freelist. Here are performance numbers for different
pre-allocation algorithms that were implemented, but discarded
in favor of percpu_freelist:
1 cpu:
pcpu_ida 2.1M
pcpu_ida nolock 2.3M
bt 2.4M
kmalloc 1.8M
hlist+spinlock 2.3M
pcpu_freelist 2.6M
4 cpu:
pcpu_ida 1.5M
pcpu_ida nolock 1.8M
bt w/smp_align 1.7M
bt no/smp_align 1.1M
kmalloc 0.7M
hlist+spinlock 0.2M
pcpu_freelist 2.0M
8 cpu:
pcpu_ida 0.7M
bt w/smp_align 0.8M
kmalloc 0.4M
pcpu_freelist 1.5M
32 cpu:
kmalloc 0.13M
pcpu_freelist 0.49M
pcpu_ida nolock is a modified percpu_ida algorithm without
percpu_ida_cpu locks and without cross-cpu tag stealing.
It's faster than existing percpu_ida, but not as fast as pcpu_freelist.
bt is a variant of block/blk-mq-tag.c simlified and customized
for bpf use case. bt w/smp_align is using cache line for every 'long'
(similar to blk-mq-tag). bt no/smp_align allocates 'long'
bitmasks continuously to save memory. It's comparable to percpu_ida
and in some cases faster, but slower than percpu_freelist
hlist+spinlock is the simplest free list with single spinlock.
As expeceted it has very bad scaling in SMP.
kmalloc is existing implementation which is still available via
BPF_F_NO_PREALLOC flag. It's significantly slower in single cpu and
in 8 cpu setup it's 3 times slower than pre-allocation with pcpu_freelist,
but saves memory, so in cases where map->max_entries can be large
and number of map update/delete per second is low, it may make
sense to use it.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
if kprobe is placed within update or delete hash map helpers
that hold bucket spin lock and triggered bpf program is trying to
grab the spinlock for the same bucket on the same cpu, it will
deadlock.
Fix it by extending existing recursion prevention mechanism.
Note, map_lookup and other tracing helpers don't have this problem,
since they don't hold any locks and don't modify global data.
bpf_trace_printk has its own recursive check and ok as well.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Currently, when we pass a buffer from the eBPF stack into a helper
function, the function proto indicates argument types as ARG_PTR_TO_STACK
and ARG_CONST_STACK_SIZE pair. If R<X> contains the former, then R<X+1>
must be of the latter type. Then, verifier checks whether the buffer
points into eBPF stack, is initialized, etc. The verifier also guarantees
that the constant value passed in R<X+1> is greater than 0, so helper
functions don't need to test for it and can always assume a non-NULL
initialized buffer as well as non-0 buffer size.
This patch adds a new argument types ARG_CONST_STACK_SIZE_OR_ZERO that
allows to also pass NULL as R<X> and 0 as R<X+1> into the helper function.
Such helper functions, of course, need to be able to handle these cases
internally then. Verifier guarantees that either R<X> == NULL && R<X+1> == 0
or R<X> != NULL && R<X+1> != 0 (like the case of ARG_CONST_STACK_SIZE), any
other combinations are not possible to load.
I went through various options of extending the verifier, and introducing
the type ARG_CONST_STACK_SIZE_OR_ZERO seems to have most minimal changes
needed to the verifier.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
add new map type to store stack traces and corresponding helper
bpf_get_stackid(ctx, map, flags) - walk user or kernel stack and return id
@ctx: struct pt_regs*
@map: pointer to stack_trace map
@flags: bits 0-7 - numer of stack frames to skip
bit 8 - collect user stack instead of kernel
bit 9 - compare stacks by hash only
bit 10 - if two different stacks hash into the same stackid
discard old
other bits - reserved
Return: >= 0 stackid on success or negative error
stackid is a 32-bit integer handle that can be further combined with
other data (including other stackid) and used as a key into maps.
Userspace will access stackmap using standard lookup/delete syscall commands to
retrieve full stack trace for given stackid.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Expose socket options for setting a classic or extended BPF program
for use when selecting sockets in an SO_REUSEPORT group. These options
can be used on the first socket to belong to a group before bind or
on any socket in the group after bind.
This change includes refactoring of the existing sk_filter code to
allow reuse of the existing BPF filter validation checks.
Signed-off-by: Craig Gallek <kraig@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Change-Id: I4433dfd5d865bb69e8d3cab55cc68325829e8b49
The functions bpf_map_lookup_elem(map, key, value) and
bpf_map_update_elem(map, key, value, flags) need to get/set
values from all-cpus for per-cpu hash and array maps,
so that user space can aggregate/update them as necessary.
Example of single counter aggregation in user space:
unsigned int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
long values[nr_cpus];
long value = 0;
bpf_lookup_elem(fd, key, values);
for (i = 0; i < nr_cpus; i++)
value += values[i];
The user space must provide round_up(value_size, 8) * nr_cpus
array to get/set values, since kernel will use 'long' copy
of per-cpu values to try to copy good counters atomically.
It's a best-effort, since bpf programs and user space are racing
to access the same memory.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Primary use case is a histogram array of latency
where bpf program computes the latency of block requests or other
events and stores histogram of latency into array of 64 elements.
All cpus are constantly running, so normal increment is not accurate,
bpf_xadd causes cache ping-pong and this per-cpu approach allows
fastest collision-free counters.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
Currently, when having map file descriptors pointing to program arrays,
there's still the issue that we unconditionally flush program array
contents via bpf_fd_array_map_clear() in bpf_map_release(). This happens
when such a file descriptor is released and is independent of the map's
refcount.
Having this flush independent of the refcount is for a reason: there
can be arbitrary complex dependency chains among tail calls, also circular
ones (direct or indirect, nesting limit determined during runtime), and
we need to make sure that the map drops all references to eBPF programs
it holds, so that the map's refcount can eventually drop to zero and
initiate its freeing. Btw, a walk of the whole dependency graph would
not be possible for various reasons, one being complexity and another
one inconsistency, i.e. new programs can be added to parts of the graph
at any time, so there's no guaranteed consistent state for the time of
such a walk.
Now, the program array pinning itself works, but the issue is that each
derived file descriptor on close would nevertheless call unconditionally
into bpf_fd_array_map_clear(). Instead, keep track of users and postpone
this flush until the last reference to a user is dropped. As this only
concerns a subset of references (f.e. a prog array could hold a program
that itself has reference on the prog array holding it, etc), we need to
track them separately.
Short analysis on the refcounting: on map creation time usercnt will be
one, so there's no change in behaviour for bpf_map_release(), if unpinned.
If we already fail in map_create(), we are immediately freed, and no
file descriptor has been made public yet. In bpf_obj_pin_user(), we need
to probe for a possible map in bpf_fd_probe_obj() already with a usercnt
reference, so before we drop the reference on the fd with fdput().
Therefore, if actual pinning fails, we need to drop that reference again
in bpf_any_put(), otherwise we keep holding it. When last reference
drops on the inode, the bpf_any_put() in bpf_evict_inode() will take
care of dropping the usercnt again. In the bpf_obj_get_user() case, the
bpf_any_get() will grab a reference on the usercnt, still at a time when
we have the reference on the path. Should we later on fail to grab a new
file descriptor, bpf_any_put() will drop it, otherwise we hold it until
bpf_map_release() time.
Joint work with Alexei.
Fixes: b2197755b2 ("bpf: add support for persistent maps/progs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chatur27 <jasonbright2709@gmail.com>
* common/android-4.4-p:
Linux 4.4.302
Input: i8042 - Fix misplaced backport of "add ASUS Zenbook Flip to noselftest list"
KVM: x86: Fix misplaced backport of "work around leak of uninitialized stack contents"
Revert "tc358743: fix register i2c_rd/wr function fix"
Revert "drm/radeon/ci: disable mclk switching for high refresh rates (v2)"
Bluetooth: MGMT: Fix misplaced BT_HS check
ipv4: tcp: send zero IPID in SYNACK messages
ipv4: raw: lock the socket in raw_bind()
hwmon: (lm90) Reduce maximum conversion rate for G781
drm/msm: Fix wrong size calculation
net-procfs: show net devices bound packet types
ipv4: avoid using shared IP generator for connected sockets
net: fix information leakage in /proc/net/ptype
ipv6_tunnel: Rate limit warning messages
scsi: bnx2fc: Flush destroy_work queue before calling bnx2fc_interface_put()
USB: core: Fix hang in usb_kill_urb by adding memory barriers
usb-storage: Add unusual-devs entry for VL817 USB-SATA bridge
tty: Add support for Brainboxes UC cards.
tty: n_gsm: fix SW flow control encoding/handling
serial: stm32: fix software flow control transfer
PM: wakeup: simplify the output logic of pm_show_wakelocks()
udf: Fix NULL ptr deref when converting from inline format
udf: Restore i_lenAlloc when inode expansion fails
scsi: zfcp: Fix failed recovery on gone remote port with non-NPIV FCP devices
s390/hypfs: include z/VM guests with access control group set
Bluetooth: refactor malicious adv data check
can: bcm: fix UAF of bcm op
Linux 4.4.301
drm/i915: Flush TLBs before releasing backing store
Linux 4.4.300
lib82596: Fix IRQ check in sni_82596_probe
bcmgenet: add WOL IRQ check
net_sched: restore "mpu xxx" handling
dmaengine: at_xdmac: Fix at_xdmac_lld struct definition
dmaengine: at_xdmac: Fix lld view setting
dmaengine: at_xdmac: Print debug message after realeasing the lock
dmaengine: at_xdmac: Don't start transactions at tx_submit level
netns: add schedule point in ops_exit_list()
net: axienet: fix number of TX ring slots for available check
net: axienet: Wait for PhyRstCmplt after core reset
af_unix: annote lockless accesses to unix_tot_inflight & gc_in_progress
parisc: pdc_stable: Fix memory leak in pdcs_register_pathentries
net/fsl: xgmac_mdio: Fix incorrect iounmap when removing module
powerpc/fsl/dts: Enable WA for erratum A-009885 on fman3l MDIO buses
ext4: don't use the orphan list when migrating an inode
ext4: Fix BUG_ON in ext4_bread when write quota data
ext4: set csum seed in tmp inode while migrating to extents
ubifs: Error path in ubifs_remount_rw() seems to wrongly free write buffers
power: bq25890: Enable continuous conversion for ADC at charging
scsi: sr: Don't use GFP_DMA
MIPS: Octeon: Fix build errors using clang
i2c: designware-pci: Fix to change data types of hcnt and lcnt parameters
ALSA: seq: Set upper limit of processed events
w1: Misuse of get_user()/put_user() reported by sparse
i2c: mpc: Correct I2C reset procedure
powerpc/smp: Move setup_profiling_timer() under CONFIG_PROFILING
i2c: i801: Don't silently correct invalid transfer size
powerpc/btext: add missing of_node_put
powerpc/cell: add missing of_node_put
powerpc/powernv: add missing of_node_put
powerpc/6xx: add missing of_node_put
parisc: Avoid calling faulthandler_disabled() twice
serial: core: Keep mctrl register state and cached copy in sync
serial: pl010: Drop CR register reset on set_termios
dm space map common: add bounds check to sm_ll_lookup_bitmap()
dm btree: add a defensive bounds check to insert_at()
net: mdio: Demote probed message to debug print
btrfs: remove BUG_ON(!eie) in find_parent_nodes
btrfs: remove BUG_ON() in find_parent_nodes()
ACPICA: Executer: Fix the REFCLASS_REFOF case in acpi_ex_opcode_1A_0T_1R()
ACPICA: Utilities: Avoid deleting the same object twice in a row
um: registers: Rename function names to avoid conflicts and build problems
ath9k: Fix out-of-bound memcpy in ath9k_hif_usb_rx_stream
usb: hub: Add delay for SuperSpeed hub resume to let links transit to U0
media: saa7146: hexium_gemini: Fix a NULL pointer dereference in hexium_attach()
media: igorplugusb: receiver overflow should be reported
net: bonding: debug: avoid printing debug logs when bond is not notifying peers
iwlwifi: mvm: synchronize with FW after multicast commands
media: m920x: don't use stack on USB reads
media: saa7146: hexium_orion: Fix a NULL pointer dereference in hexium_attach()
floppy: Add max size check for user space request
mwifiex: Fix skb_over_panic in mwifiex_usb_recv()
HSI: core: Fix return freed object in hsi_new_client
media: b2c2: Add missing check in flexcop_pci_isr:
usb: gadget: f_fs: Use stream_open() for endpoint files
ar5523: Fix null-ptr-deref with unexpected WDCMSG_TARGET_START reply
fs: dlm: filter user dlm messages for kernel locks
Bluetooth: Fix debugfs entry leak in hci_register_dev()
RDMA/cxgb4: Set queue pair state when being queried
mips: bcm63xx: add support for clk_set_parent()
mips: lantiq: add support for clk_set_parent()
misc: lattice-ecp3-config: Fix task hung when firmware load failed
ASoC: samsung: idma: Check of ioremap return value
dmaengine: pxa/mmp: stop referencing config->slave_id
RDMA/core: Let ib_find_gid() continue search even after empty entry
char/mwave: Adjust io port register size
ALSA: oss: fix compile error when OSS_DEBUG is enabled
powerpc/prom_init: Fix improper check of prom_getprop()
ALSA: hda: Add missing rwsem around snd_ctl_remove() calls
ALSA: PCM: Add missing rwsem around snd_ctl_remove() calls
ALSA: jack: Add missing rwsem around snd_ctl_remove() calls
ext4: avoid trim error on fs with small groups
net: mcs7830: handle usb read errors properly
pcmcia: fix setting of kthread task states
can: xilinx_can: xcan_probe(): check for error irq
can: softing: softing_startstop(): fix set but not used variable warning
spi: spi-meson-spifc: Add missing pm_runtime_disable() in meson_spifc_probe
ppp: ensure minimum packet size in ppp_write()
pcmcia: rsrc_nonstatic: Fix a NULL pointer dereference in nonstatic_find_mem_region()
pcmcia: rsrc_nonstatic: Fix a NULL pointer dereference in __nonstatic_find_io_region()
usb: ftdi-elan: fix memory leak on device disconnect
media: msi001: fix possible null-ptr-deref in msi001_probe()
media: saa7146: mxb: Fix a NULL pointer dereference in mxb_attach()
media: dib8000: Fix a memleak in dib8000_init()
floppy: Fix hang in watchdog when disk is ejected
serial: amba-pl011: do not request memory region twice
drm/amdgpu: Fix a NULL pointer dereference in amdgpu_connector_lcd_native_mode()
arm64: dts: qcom: msm8916: fix MMC controller aliases
netfilter: bridge: add support for pppoe filtering
tty: serial: atmel: Call dma_async_issue_pending()
tty: serial: atmel: Check return code of dmaengine_submit()
crypto: qce - fix uaf on qce_ahash_register_one
Bluetooth: stop proccessing malicious adv data
Bluetooth: cmtp: fix possible panic when cmtp_init_sockets() fails
PCI: Add function 1 DMA alias quirk for Marvell 88SE9125 SATA controller
can: softing_cs: softingcs_probe(): fix memleak on registration failure
media: stk1160: fix control-message timeouts
media: pvrusb2: fix control-message timeouts
media: dib0700: fix undefined behavior in tuner shutdown
media: em28xx: fix control-message timeouts
media: mceusb: fix control-message timeouts
rtc: cmos: take rtc_lock while reading from CMOS
nfc: llcp: fix NULL error pointer dereference on sendmsg() after failed bind()
HID: uhid: Fix worker destroying device without any protection
rtlwifi: rtl8192cu: Fix WARNING when calling local_irq_restore() with interrupts enabled
media: uvcvideo: fix division by zero at stream start
drm/i915: Avoid bitwise vs logical OR warning in snb_wm_latency_quirk()
can: gs_usb: gs_can_start_xmit(): zero-initialize hf->{flags,reserved}
can: gs_usb: fix use of uninitialized variable, detach device on reception of invalid USB data
mfd: intel-lpss: Fix too early PM enablement in the ACPI ->probe()
USB: Fix "slab-out-of-bounds Write" bug in usb_hcd_poll_rh_status
USB: core: Fix bug in resuming hub's handling of wakeup requests
Bluetooth: bfusb: fix division by zero in send path
Linux 4.4.299
power: reset: ltc2952: Fix use of floating point literals
mISDN: change function names to avoid conflicts
net: udp: fix alignment problem in udp4_seq_show()
ip6_vti: initialize __ip6_tnl_parm struct in vti6_siocdevprivate
scsi: libiscsi: Fix UAF in iscsi_conn_get_param()/iscsi_conn_teardown()
phonet: refcount leak in pep_sock_accep
rndis_host: support Hytera digital radios
xfs: map unwritten blocks in XFS_IOC_{ALLOC,FREE}SP just like fallocate
sch_qfq: prevent shift-out-of-bounds in qfq_init_qdisc
i40e: Fix incorrect netdev's real number of RX/TX queues
mac80211: initialize variable have_higher_than_11mbit
ieee802154: atusb: fix uninit value in atusb_set_extended_addr
Bluetooth: btusb: Apply QCA Rome patches for some ATH3012 models
bpf, test: fix ld_abs + vlan push/pop stress test
Linux 4.4.298
net: fix use-after-free in tw_timer_handler
Input: spaceball - fix parsing of movement data packets
Input: appletouch - initialize work before device registration
scsi: vmw_pvscsi: Set residual data length conditionally
usb: gadget: f_fs: Clear ffs_eventfd in ffs_data_clear.
xhci: Fresco FL1100 controller should not have BROKEN_MSI quirk set.
uapi: fix linux/nfc.h userspace compilation errors
nfc: uapi: use kernel size_t to fix user-space builds
selinux: initialize proto variable in selinux_ip_postroute_compat()
recordmcount.pl: fix typo in s390 mcount regex
platform/x86: apple-gmux: use resource_size() with res
Linux 4.4.297
phonet/pep: refuse to enable an unbound pipe
hamradio: improve the incomplete fix to avoid NPD
hamradio: defer ax25 kfree after unregister_netdev
ax25: NPD bug when detaching AX25 device
xen/blkfront: fix bug in backported patch
ARM: 9169/1: entry: fix Thumb2 bug in iWMMXt exception handling
ALSA: drivers: opl3: Fix incorrect use of vp->state
ALSA: jack: Check the return value of kstrdup()
hwmon: (lm90) Fix usage of CONFIG2 register in detect function
drivers: net: smc911x: Check for error irq
bonding: fix ad_actor_system option setting to default
qlcnic: potential dereference null pointer of rx_queue->page_ring
IB/qib: Fix memory leak in qib_user_sdma_queue_pkts()
HID: holtek: fix mouse probing
can: kvaser_usb: get CAN clock frequency from device
net: usb: lan78xx: add Allied Telesis AT29M2-AF
Conflicts:
drivers/usb/gadget/function/f_fs.c
Change-Id: I54140777477cbab1b4c6b7d77558e92ca2b30e96
Changes in 4.4.302
can: bcm: fix UAF of bcm op
Bluetooth: refactor malicious adv data check
s390/hypfs: include z/VM guests with access control group set
scsi: zfcp: Fix failed recovery on gone remote port with non-NPIV FCP devices
udf: Restore i_lenAlloc when inode expansion fails
udf: Fix NULL ptr deref when converting from inline format
PM: wakeup: simplify the output logic of pm_show_wakelocks()
serial: stm32: fix software flow control transfer
tty: n_gsm: fix SW flow control encoding/handling
tty: Add support for Brainboxes UC cards.
usb-storage: Add unusual-devs entry for VL817 USB-SATA bridge
USB: core: Fix hang in usb_kill_urb by adding memory barriers
scsi: bnx2fc: Flush destroy_work queue before calling bnx2fc_interface_put()
ipv6_tunnel: Rate limit warning messages
net: fix information leakage in /proc/net/ptype
ipv4: avoid using shared IP generator for connected sockets
net-procfs: show net devices bound packet types
drm/msm: Fix wrong size calculation
hwmon: (lm90) Reduce maximum conversion rate for G781
ipv4: raw: lock the socket in raw_bind()
ipv4: tcp: send zero IPID in SYNACK messages
Bluetooth: MGMT: Fix misplaced BT_HS check
Revert "drm/radeon/ci: disable mclk switching for high refresh rates (v2)"
Revert "tc358743: fix register i2c_rd/wr function fix"
KVM: x86: Fix misplaced backport of "work around leak of uninitialized stack contents"
Input: i8042 - Fix misplaced backport of "add ASUS Zenbook Flip to noselftest list"
Linux 4.4.302
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I5191d3cb4df0fa8de60170d2fedf4a3c51380fdf
commit 47934e06b65637c88a762d9c98329ae6e3238888 upstream.
In one net namespace, after creating a packet socket without binding
it to a device, users in other net namespaces can observe the new
`packet_type` added by this packet socket by reading `/proc/net/ptype`
file. This is minor information leakage as packet socket is
namespace aware.
Add a net pointer in `packet_type` to keep the net namespace of
of corresponding packet socket. In `ptype_seq_show`, this net pointer
must be checked when it is not NULL.
Fixes: 2feb27dbe0 ("[NETNS]: Minor information leak via /proc/net/ptype file.")
Signed-off-by: Congyu Liu <liu3101@purdue.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
* common/android-4.4-p:
Linux 4.4.296
xen/netback: don't queue unlimited number of packages
xen/console: harden hvc_xen against event channel storms
xen/netfront: harden netfront against event channel storms
xen/blkfront: harden blkfront against event channel storms
Input: touchscreen - avoid bitwise vs logical OR warning
ARM: 8805/2: remove unneeded naked function usage
net: lan78xx: Avoid unnecessary self assignment
net: systemport: Add global locking for descriptor lifecycle
timekeeping: Really make sure wall_to_monotonic isn't positive
USB: serial: option: add Telit FN990 compositions
PCI/MSI: Clear PCI_MSIX_FLAGS_MASKALL on error
USB: gadget: bRequestType is a bitfield, not a enum
igbvf: fix double free in `igbvf_probe`
soc/tegra: fuse: Fix bitwise vs. logical OR warning
nfsd: fix use-after-free due to delegation race
dm btree remove: fix use after free in rebalance_children()
recordmcount.pl: look for jgnop instruction as well as bcrl on s390
mac80211: send ADDBA requests using the tid/queue of the aggregation session
hwmon: (dell-smm) Fix warning on /proc/i8k creation error
net: netlink: af_netlink: Prevent empty skb by adding a check on len.
i2c: rk3x: Handle a spurious start completion interrupt flag
parisc/agp: Annotate parisc agp init functions with __init
nfc: fix segfault in nfc_genl_dump_devices_done
FROMGIT: USB: gadget: bRequestType is a bitfield, not a enum
Linux 4.4.295
irqchip: nvic: Fix offset for Interrupt Priority Offsets
irqchip/irq-gic-v3-its.c: Force synchronisation when issuing INVALL
iio: accel: kxcjk-1013: Fix possible memory leak in probe and remove
iio: itg3200: Call iio_trigger_notify_done() on error
iio: ltr501: Don't return error code in trigger handler
iio: mma8452: Fix trigger reference couting
iio: stk3310: Don't return error code in interrupt handler
usb: core: config: fix validation of wMaxPacketValue entries
USB: gadget: zero allocate endpoint 0 buffers
USB: gadget: detect too-big endpoint 0 requests
net/qla3xxx: fix an error code in ql_adapter_up()
net, neigh: clear whole pneigh_entry at alloc time
net: fec: only clear interrupt of handling queue in fec_enet_rx_queue()
net: altera: set a couple error code in probe()
net: cdc_ncm: Allow for dwNtbOutMaxSize to be unset or zero
block: fix ioprio_get(IOPRIO_WHO_PGRP) vs setuid(2)
tracefs: Set all files to the same group ownership as the mount option
signalfd: use wake_up_pollfree()
binder: use wake_up_pollfree()
wait: add wake_up_pollfree()
libata: add horkage for ASMedia 1092
can: pch_can: pch_can_rx_normal: fix use after free
tracefs: Have new files inherit the ownership of their parent
ALSA: pcm: oss: Handle missing errors in snd_pcm_oss_change_params*()
ALSA: pcm: oss: Limit the period size to 16MB
ALSA: pcm: oss: Fix negative period/buffer sizes
ALSA: ctl: Fix copy of updated id with element read/write
mm: bdi: initialize bdi_min_ratio when bdi is unregistered
nfc: fix potential NULL pointer deref in nfc_genl_dump_ses_done
can: sja1000: fix use after free in ems_pcmcia_add_card()
HID: check for valid USB device for many HID drivers
HID: wacom: fix problems when device is not a valid USB device
HID: add USB_HID dependancy on some USB HID drivers
HID: add USB_HID dependancy to hid-chicony
HID: add USB_HID dependancy to hid-prodikeys
HID: add hid_is_usb() function to make it simpler for USB detection
HID: introduce hid_is_using_ll_driver
UPSTREAM: USB: gadget: zero allocate endpoint 0 buffers
UPSTREAM: USB: gadget: detect too-big endpoint 0 requests
Linux 4.4.294
serial: pl011: Add ACPI SBSA UART match id
tty: serial: msm_serial: Deactivate RX DMA for polling support
vgacon: Propagate console boot parameters before calling `vc_resize'
parisc: Fix "make install" on newer debian releases
siphash: use _unaligned version by default
net: qlogic: qlcnic: Fix a NULL pointer dereference in qlcnic_83xx_add_rings()
natsemi: xtensa: fix section mismatch warnings
fget: check that the fd still exists after getting a ref to it
fs: add fget_many() and fput_many()
sata_fsl: fix warning in remove_proc_entry when rmmod sata_fsl
sata_fsl: fix UAF in sata_fsl_port_stop when rmmod sata_fsl
kprobes: Limit max data_size of the kretprobe instances
net: ethernet: dec: tulip: de4x5: fix possible array overflows in type3_infoblock()
net: tulip: de4x5: fix the problem that the array 'lp->phy[8]' may be out of bound
scsi: iscsi: Unblock session then wake up error handler
s390/setup: avoid using memblock_enforce_memory_limit
platform/x86: thinkpad_acpi: Fix WWAN device disabled issue after S3 deep
net: return correct error code
hugetlb: take PMD sharing into account when flushing tlb/caches
tty: hvc: replace BUG_ON() with negative return value
xen/netfront: don't trust the backend response data blindly
xen/netfront: disentangle tx_skb_freelist
xen/netfront: don't read data from request on the ring page
xen/netfront: read response from backend only once
xen/blkfront: don't trust the backend response data blindly
xen/blkfront: don't take local copy of a request from the ring page
xen/blkfront: read response from backend only once
xen: sync include/xen/interface/io/ring.h with Xen's newest version
shm: extend forced shm destroy to support objects from several IPC nses
fuse: release pipe buf after last use
fuse: fix page stealing
NFC: add NCI_UNREG flag to eliminate the race
proc/vmcore: fix clearing user buffer by properly using clear_user()
hugetlbfs: flush TLBs correctly after huge_pmd_unshare
tracing: Check pid filtering when creating events
tcp_cubic: fix spurious Hystart ACK train detections for not-cwnd-limited flows
scsi: mpt3sas: Fix kernel panic during drive powercycle test
ARM: socfpga: Fix crash with CONFIG_FORTIRY_SOURCE
NFSv42: Don't fail clone() unless the OP_CLONE operation failed
net: ieee802154: handle iftypes as u32
ASoC: topology: Add missing rwsem around snd_ctl_remove() calls
ARM: dts: BCM5301X: Add interrupt properties to GPIO node
xen: detect uninitialized xenbus in xenbus_init
xen: don't continue xenstore initialization in case of errors
staging: rtl8192e: Fix use after free in _rtl92e_pci_disconnect()
ALSA: ctxfi: Fix out-of-range access
binder: fix test regression due to sender_euid change
usb: hub: Fix locking issues with address0_mutex
usb: hub: Fix usb enumeration issue due to address0 race
USB: serial: option: add Fibocom FM101-GL variants
USB: serial: option: add Telit LE910S1 0x9200 composition
staging: ion: Prevent incorrect reference counting behavour
Conflicts:
fs/file_table.c
Change-Id: Ie66d41bc083d3d53fc89fba73b6e57bcc18e1c4a
* common/android-4.4-p:
Linux 4.4.293
usb: max-3421: Use driver data instead of maintaining a list of bound devices
ASoC: DAPM: Cover regression by kctl change notification fix
batman-adv: Avoid WARN_ON timing related checks
batman-adv: Don't always reallocate the fragmentation skb head
batman-adv: Reserve needed_*room for fragments
batman-adv: Consider fragmentation for needed_headroom
batman-adv: set .owner to THIS_MODULE
batman-adv: mcast: fix duplicate mcast packets from BLA backbone to mesh
batman-adv: mcast: fix duplicate mcast packets in BLA backbone from mesh
batman-adv: mcast: fix duplicate mcast packets in BLA backbone from LAN
batman-adv: Prevent duplicated softif_vlan entry
batman-adv: Fix multicast TT issues with bogus ROAM flags
batman-adv: Keep fragments equally sized
drm/amdgpu: fix set scaling mode Full/Full aspect/Center not works on vga and dvi connectors
drm/udl: fix control-message timeout
cfg80211: call cfg80211_stop_ap when switch from P2P_GO type
parisc/sticon: fix reverse colors
btrfs: fix memory ordering between normal and ordered work functions
mm: kmemleak: slob: respect SLAB_NOLEAKTRACE flag
hexagon: export raw I/O routines for modules
tun: fix bonding active backup with arp monitoring
NFC: reorder the logic in nfc_{un,}register_device
NFC: reorganize the functions in nci_request
platform/x86: hp_accel: Fix an error handling path in 'lis3lv02d_probe()'
mips: bcm63xx: add support for clk_get_parent()
net: bnx2x: fix variable dereferenced before check
sched/core: Mitigate race cpus_share_cache()/update_top_cache_domain()
mips: BCM63XX: ensure that CPU_SUPPORTS_32BIT_KERNEL is set
sh: define __BIG_ENDIAN for math-emu
sh: fix kconfig unmet dependency warning for FRAME_POINTER
maple: fix wrong return value of maple_bus_init().
sh: check return code of request_irq
powerpc/dcr: Use cmplwi instead of 3-argument cmpli
ALSA: gus: fix null pointer dereference on pointer block
powerpc/5200: dts: fix memory node unit name
scsi: target: Fix alua_tg_pt_gps_count tracking
scsi: target: Fix ordered tag handling
MIPS: sni: Fix the build
tty: tty_buffer: Fix the softlockup issue in flush_to_ldisc
usb: host: ohci-tmio: check return value after calling platform_get_resource()
ARM: dts: omap: fix gpmc,mux-add-data type
scsi: advansys: Fix kernel pointer leak
usb: musb: tusb6010: check return value after calling platform_get_resource()
scsi: lpfc: Fix list_add() corruption in lpfc_drain_txq()
net: batman-adv: fix error handling
PCI/MSI: Destroy sysfs before freeing entries
parisc/entry: fix trace test in syscall exit path
PCI: Add PCI_EXP_DEVCTL_PAYLOAD_* macros
mm, oom: pagefault_out_of_memory: don't force global OOM for dying tasks
ARM: 9156/1: drop cc-option fallbacks for architecture selection
USB: chipidea: fix interrupt deadlock
vsock: prevent unnecessary refcnt inc for nonblocking connect
nfc: pn533: Fix double free when pn533_fill_fragment_skbs() fails
llc: fix out-of-bound array index in llc_sk_dev_hash()
bonding: Fix a use-after-free problem when bond_sysfs_slave_add() failed
net: davinci_emac: Fix interrupt pacing disable
xen-pciback: Fix return in pm_ctrl_init()
scsi: qla2xxx: Turn off target reset during issue_lip
watchdog: f71808e_wdt: fix inaccurate report in WDIOC_GETTIMEOUT
m68k: set a default value for MEMORY_RESERVE
netfilter: nfnetlink_queue: fix OOB when mac header was cleared
dmaengine: at_xdmac: fix AT_XDMAC_CC_PERID() macro
RDMA/mlx4: Return missed an error if device doesn't support steering
scsi: csiostor: Uninitialized data in csio_ln_vnp_read_cbfn()
power: supply: rt5033_battery: Change voltage values to µV
usb: gadget: hid: fix error code in do_config()
serial: 8250_dw: Drop wrong use of ACPI_PTR()
video: fbdev: chipsfb: use memset_io() instead of memset()
memory: fsl_ifc: fix leak of irq and nand_irq in fsl_ifc_ctrl_probe
JFS: fix memleak in jfs_mount
scsi: dc395: Fix error case unwinding
ARM: s3c: irq-s3c24xx: Fix return value check for s3c24xx_init_intc()
crypto: pcrypt - Delay write to padata->info
libertas: Fix possible memory leak in probe and disconnect
libertas_tf: Fix possible memory leak in probe and disconnect
smackfs: use netlbl_cfg_cipsov4_del() for deleting cipso_v4_doi
mwifiex: Send DELBA requests according to spec
platform/x86: thinkpad_acpi: Fix bitwise vs. logical warning
net: stream: don't purge sk_error_queue in sk_stream_kill_queues()
drm/msm: uninitialized variable in msm_gem_import()
memstick: jmb38x_ms: use appropriate free function in jmb38x_ms_alloc_host()
memstick: avoid out-of-range warning
b43: fix a lower bounds test
b43legacy: fix a lower bounds test
crypto: qat - detect PFVF collision after ACK
ath9k: Fix potential interrupt storm on queue reset
cpuidle: Fix kobject memory leaks in error paths
media: si470x: Avoid card name truncation
media: dvb-usb: fix ununit-value in az6027_rc_query
parisc/kgdb: add kgdb_roundup() to make kgdb work with idle polling
parisc: fix warning in flush_tlb_all
ARM: 9136/1: ARMv7-M uses BE-8, not BE-32
ARM: clang: Do not rely on lr register for stacktrace
smackfs: use __GFP_NOFAIL for smk_cipso_doi()
iwlwifi: mvm: disable RX-diversity in powersave
PM: hibernate: Get block device exclusively in swsusp_check()
mwl8k: Fix use-after-free in mwl8k_fw_state_machine()
lib/xz: Validate the value before assigning it to an enum variable
lib/xz: Avoid overlapping memcpy() with invalid input with in-place decompression
memstick: r592: Fix a UAF bug when removing the driver
ACPI: battery: Accept charges over the design capacity as full
ath: dfs_pattern_detector: Fix possible null-pointer dereference in channel_detector_create()
tracefs: Have tracefs directories not set OTH permission bits by default
media: usb: dvd-usb: fix uninit-value bug in dibusb_read_eeprom_byte()
ACPICA: Avoid evaluating methods too early during system resume
ia64: don't do IA64_CMPXCHG_DEBUG without CONFIG_PRINTK
media: mceusb: return without resubmitting URB in case of -EPROTO error.
media: s5p-mfc: fix possible null-pointer dereference in s5p_mfc_probe()
media: uvcvideo: Set capability in s_param
media: netup_unidvb: handle interrupt properly according to the firmware
media: mt9p031: Fix corrupted frame after restarting stream
x86: Increase exception stack sizes
smackfs: Fix use-after-free in netlbl_catmap_walk()
MIPS: lantiq: dma: reset correct number of channel
MIPS: lantiq: dma: add small delay after reset
platform/x86: wmi: do not fail if disabling fails
Bluetooth: fix use-after-free error in lock_sock_nested()
Bluetooth: sco: Fix lock_sock() blockage by memcpy_from_msg()
USB: iowarrior: fix control-message timeouts
USB: serial: keyspan: fix memleak on probe errors
iio: dac: ad5446: Fix ad5622_write() return value
quota: correct error number in free_dqentry()
quota: check block number when reading the block in quota file
ALSA: mixer: fix deadlock in snd_mixer_oss_set_volume
ALSA: mixer: oss: Fix racy access to slots
power: supply: max17042_battery: use VFSOC for capacity when no rsns
power: supply: max17042_battery: Prevent int underflow in set_soc_threshold
signal: Remove the bogus sigkill_pending in ptrace_stop
mwifiex: Read a PCI register after writing the TX ring write pointer
wcn36xx: Fix HT40 capability for 2Ghz band
PCI: Mark Atheros QCA6174 to avoid bus reset
ath6kl: fix control-message timeout
ath6kl: fix division by zero in send path
mwifiex: fix division by zero in fw download path
EDAC/sb_edac: Fix top-of-high-memory value for Broadwell/Haswell
hwmon: (pmbus/lm25066) Add offset coefficients
btrfs: fix lost error handling when replaying directory deletes
vmxnet3: do not stop tx queues after netif_device_detach()
spi: spl022: fix Microwire full duplex mode
xen/netfront: stop tx queues during live migration
mmc: winbond: don't build on M68K
hyperv/vmbus: include linux/bitops.h
x86/irq: Ensure PI wakeup handler is unregistered before module unload
ALSA: timer: Unconditionally unlink slave instances, too
ALSA: timer: Fix use-after-free problem
ALSA: synth: missing check for possible NULL after the call to kstrdup
ALSA: line6: fix control and interrupt message timeouts
ALSA: 6fire: fix control and bulk message timeouts
ALSA: ua101: fix division by zero at probe
media: ite-cir: IR receiver stop working after receive overflow
parisc: Fix ptrace check on syscall return
mmc: dw_mmc: Dont wait for DRTO on Write RSP error
ocfs2: fix data corruption on truncate
libata: fix read log timeout value
Input: i8042 - Add quirk for Fujitsu Lifebook T725
Input: elantench - fix misreporting trackpoint coordinates
xhci: Fix USB 3.1 enumeration issues by increasing roothub power-on-good delay
binder: use cred instead of task for selinux checks
binder: use euid from cred instead of using task
FROMGIT: binder: fix test regression due to sender_euid change
BACKPORT: binder: use cred instead of task for selinux checks
BACKPORT: binder: use euid from cred instead of using task
BACKPORT: ip_gre: add validation for csum_start
Linux 4.4.292
rsi: fix control-message timeout
staging: rtl8192u: fix control-message timeouts
staging: r8712u: fix control-message timeout
comedi: vmk80xx: fix bulk and interrupt message timeouts
comedi: vmk80xx: fix bulk-buffer overflow
comedi: vmk80xx: fix transfer-buffer overflows
staging: comedi: drivers: replace le16_to_cpu() with usb_endpoint_maxp()
comedi: ni_usb6501: fix NULL-deref in command paths
comedi: dt9812: fix DMA buffers on stack
isofs: Fix out of bound access for corrupted isofs image
usb: hso: fix error handling code of hso_create_net_device
printk/console: Allow to disable console output by using console="" or console=null
usb-storage: Add compatibility quirk flags for iODD 2531/2541
usb: gadget: Mark USB_FSL_QE broken on 64-bit
IB/qib: Protect from buffer overflow in struct qib_user_sdma_pkt fields
IB/qib: Use struct_size() helper
net: hso: register netdev later to avoid a race condition
ARM: 9120/1: Revert "amba: make use of -1 IRQs warn"
scsi: core: Put LLD module refcnt after SCSI device is released
Conflicts:
net/bluetooth/l2cap_sock.c
Change-Id: I066f7145b7245f9c95e1c78f84f0871a9825150f
Changes in 4.4.295
HID: introduce hid_is_using_ll_driver
HID: add hid_is_usb() function to make it simpler for USB detection
HID: add USB_HID dependancy to hid-prodikeys
HID: add USB_HID dependancy to hid-chicony
HID: add USB_HID dependancy on some USB HID drivers
HID: wacom: fix problems when device is not a valid USB device
HID: check for valid USB device for many HID drivers
can: sja1000: fix use after free in ems_pcmcia_add_card()
nfc: fix potential NULL pointer deref in nfc_genl_dump_ses_done
mm: bdi: initialize bdi_min_ratio when bdi is unregistered
ALSA: ctl: Fix copy of updated id with element read/write
ALSA: pcm: oss: Fix negative period/buffer sizes
ALSA: pcm: oss: Limit the period size to 16MB
ALSA: pcm: oss: Handle missing errors in snd_pcm_oss_change_params*()
tracefs: Have new files inherit the ownership of their parent
can: pch_can: pch_can_rx_normal: fix use after free
libata: add horkage for ASMedia 1092
wait: add wake_up_pollfree()
binder: use wake_up_pollfree()
signalfd: use wake_up_pollfree()
tracefs: Set all files to the same group ownership as the mount option
block: fix ioprio_get(IOPRIO_WHO_PGRP) vs setuid(2)
net: cdc_ncm: Allow for dwNtbOutMaxSize to be unset or zero
net: altera: set a couple error code in probe()
net: fec: only clear interrupt of handling queue in fec_enet_rx_queue()
net, neigh: clear whole pneigh_entry at alloc time
net/qla3xxx: fix an error code in ql_adapter_up()
USB: gadget: detect too-big endpoint 0 requests
USB: gadget: zero allocate endpoint 0 buffers
usb: core: config: fix validation of wMaxPacketValue entries
iio: stk3310: Don't return error code in interrupt handler
iio: mma8452: Fix trigger reference couting
iio: ltr501: Don't return error code in trigger handler
iio: itg3200: Call iio_trigger_notify_done() on error
iio: accel: kxcjk-1013: Fix possible memory leak in probe and remove
irqchip/irq-gic-v3-its.c: Force synchronisation when issuing INVALL
irqchip: nvic: Fix offset for Interrupt Priority Offsets
Linux 4.4.295
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I4810f7e2ebd538739fb0d62f9eade0921a9badfb
commit 42288cb44c4b5fff7653bc392b583a2b8bd6a8c0 upstream.
Several ->poll() implementations are special in that they use a
waitqueue whose lifetime is the current task, rather than the struct
file as is normally the case. This is okay for blocking polls, since a
blocking poll occurs within one task; however, non-blocking polls
require another solution. This solution is for the queue to be cleared
before it is freed, using 'wake_up_poll(wq, EPOLLHUP | POLLFREE);'.
However, that has a bug: wake_up_poll() calls __wake_up() with
nr_exclusive=1. Therefore, if there are multiple "exclusive" waiters,
and the wakeup function for the first one returns a positive value, only
that one will be called. That's *not* what's needed for POLLFREE;
POLLFREE is special in that it really needs to wake up everyone.
Considering the three non-blocking poll systems:
- io_uring poll doesn't handle POLLFREE at all, so it is broken anyway.
- aio poll is unaffected, since it doesn't support exclusive waits.
However, that's fragile, as someone could add this feature later.
- epoll doesn't appear to be broken by this, since its wakeup function
returns 0 when it sees POLLFREE. But this is fragile.
Although there is a workaround (see epoll), it's better to define a
function which always sends POLLFREE to all waiters. Add such a
function. Also make it verify that the queue really becomes empty after
all waiters have been woken up.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211209010455.42744-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
