linux-stable.git/kernel, branch v4.4.169

tracing: Fix memory leak of instance function hash filters

2018-12-21T13:09:51+00:00

commit 2840f84f74035e5a535959d5f17269c69fa6edc5 upstream.

The following commands will cause a memory leak:

 # cd /sys/kernel/tracing
 # mkdir instances/foo
 # echo schedule > instance/foo/set_ftrace_filter
 # rmdir instances/foo

The reason is that the hashes that hold the filters to set_ftrace_filter and
set_ftrace_notrace are not freed if they contain any data on the instance
and the instance is removed.

Found by kmemleak detector.

Cc: stable@vger.kernel.org
Fixes: 591dffdade9f ("ftrace: Allow for function tracing instance to filter functions")
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Greg Kroah-Hartman

tracing: Fix memory leak in set_trigger_filter()

2018-12-21T13:09:51+00:00

commit 3cec638b3d793b7cacdec5b8072364b41caeb0e1 upstream.

When create_event_filter() fails in set_trigger_filter(), the filter may
still be allocated and needs to be freed. The caller expects the
data->filter to be updated with the new filter, even if the new filter
failed (we could add an error message by setting set_str parameter of
create_event_filter(), but that's another update).

But because the error would just exit, filter was left hanging and
nothing could free it.

Found by kmemleak detector.

Cc: stable@vger.kernel.org
Fixes: bac5fb97a173a ("tracing: Add and use generic set_trigger_filter() implementation")
Reviewed-by: Tom Zanussi 
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Greg Kroah-Hartman

timer/debug: Change /proc/timer_list from 0444 to 0400

2018-12-21T13:09:49+00:00

[ Upstream commit 8e7df2b5b7f245c9bd11064712db5cb69044a362 ]

While it uses %pK, there's still few reasons to read this file
as non-root.

Suggested-by: Linus Torvalds 
Acked-by: Thomas Gleixner 
Cc: Peter Zijlstra 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin

mm: replace get_user_pages() write/force parameters with gup_flags

2018-12-17T20:55:16+00:00

commit 768ae309a96103ed02eb1e111e838c87854d8b51 upstream.

This removes the 'write' and 'force' from get_user_pages() and replaces
them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers
as use of this flag can result in surprising behaviour (and hence bugs)
within the mm subsystem.

Signed-off-by: Lorenzo Stoakes 
Acked-by: Christian König 
Acked-by: Jesper Nilsson 
Acked-by: Michal Hocko 
Reviewed-by: Jan Kara 
Signed-off-by: Linus Torvalds 
[bwh: Backported to 4.4:
 - Drop changes in rapidio, vchiq, goldfish
 - Keep the "write" variable in amdgpu_ttm_tt_pin_userptr() as it's still
   needed
 - Also update calls from various other places that now use
   get_user_pages_remote() upstream, which were updated there by commit
   9beae1ea8930 "mm: replace get_user_pages_remote() write/force ..."
 - Also update calls from hfi1 and ipath
 - Adjust context]
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

posix-timers: Sanitize overrun handling

2018-12-17T20:55:15+00:00

commit 78c9c4dfbf8c04883941445a195276bb4bb92c76 upstream.

The posix timer overrun handling is broken because the forwarding functions
can return a huge number of overruns which does not fit in an int. As a
consequence timer_getoverrun(2) and siginfo::si_overrun can turn into
random number generators.

The k_clock::timer_forward() callbacks return a 64 bit value now. Make
k_itimer::ti_overrun[_last] 64bit as well, so the kernel internal
accounting is correct. 3Remove the temporary (int) casts.

Add a helper function which clamps the overrun value returned to user space
via timer_getoverrun(2) or siginfo::si_overrun limited to a positive value
between 0 and INT_MAX. INT_MAX is an indicator for user space that the
overrun value has been clamped.

Reported-by: Team OWL337 
Signed-off-by: Thomas Gleixner 
Acked-by: John Stultz 
Cc: Peter Zijlstra 
Cc: Michael Kerrisk 
Link: https://lkml.kernel.org/r/20180626132705.018623573@linutronix.de
[florian: Make patch apply to v4.9.135]
Signed-off-by: Florian Fainelli 
Reviewed-by: Thomas Gleixner 
Signed-off-by: Sasha Levin 
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

bpf: Prevent memory disambiguation attack

2018-12-17T20:55:15+00:00

commit af86ca4e3088fe5eacf2f7e58c01fa68ca067672 upstream.

Detect code patterns where malicious 'speculative store bypass' can be used
and sanitize such patterns.

 39: (bf) r3 = r10
 40: (07) r3 += -216
 41: (79) r8 = *(u64 *)(r7 +0)   // slow read
 42: (7a) *(u64 *)(r10 -72) = 0  // verifier inserts this instruction
 43: (7b) *(u64 *)(r8 +0) = r3   // this store becomes slow due to r8
 44: (79) r1 = *(u64 *)(r6 +0)   // cpu speculatively executes this load
 45: (71) r2 = *(u8 *)(r1 +0)    // speculatively arbitrary 'load byte'
                                 // is now sanitized

Above code after x86 JIT becomes:
 e5: mov    %rbp,%rdx
 e8: add    $0xffffffffffffff28,%rdx
 ef: mov    0x0(%r13),%r14
 f3: movq   $0x0,-0x48(%rbp)
 fb: mov    %rdx,0x0(%r14)
 ff: mov    0x0(%rbx),%rdi
103: movzbq 0x0(%rdi),%rsi

Signed-off-by: Alexei Starovoitov 
Signed-off-by: Thomas Gleixner 
[bwh: Backported to 4.4:
 - Add verifier_env parameter to check_stack_write()
 - Look up stack slot_types with state->stack_slot_type[] rather than
   state->stack[].slot_type[]
 - Drop bpf_verifier_env argument to verbose()
 - Adjust filename, context]
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

bpf/verifier: Pass instruction index to check_mem_access() and check_xadd()

2018-12-17T20:55:15+00:00

Extracted from commit 31fd85816dbe "bpf: permits narrower load from
bpf program context fields".

Cc: Daniel Borkmann 
Cc: Alexei Starovoitov 
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

bpf/verifier: Add spi variable to check_stack_write()

2018-12-17T20:55:15+00:00

Extracted from commit dc503a8ad984 "bpf/verifier: track liveness for
pruning".

Cc: Daniel Borkmann 
Cc: Alexei Starovoitov 
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

bpf: support 8-byte metafield access

2018-12-17T20:55:15+00:00

commit cedaf52693f02372010548c63b2e63228b959099 upstream.

The verifier supported only 4-byte metafields in
struct __sk_buff and struct xdp_md. The metafields in upcoming
struct bpf_perf_event are 8-byte to match register width in struct pt_regs.
Teach verifier to recognize 8-byte metafield access.
The patch doesn't affect safety of sockets and xdp programs.
They check for 4-byte only ctx access before these conditions are hit.

Signed-off-by: Alexei Starovoitov 
Acked-by: Daniel Borkmann 
Signed-off-by: David S. Miller 
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

bpf: fix check of allowed specifiers in bpf_trace_printk

2018-12-17T20:55:10+00:00

[ Upstream commit 1efb6ee3edea57f57f9fb05dba8dcb3f7333f61f ]

A format string consisting of "%p" or "%s" followed by an invalid
specifier (e.g. "%p%\n" or "%s%") could pass the check which
would make format_decode (lib/vsprintf.c) to warn.

Fixes: 9c959c863f82 ("tracing: Allow BPF programs to call bpf_trace_printk()")
Reported-by: syzbot+1ec5c5ec949c4adaa0c4@syzkaller.appspotmail.com
Signed-off-by: Martynas Pumputis 
Signed-off-by: Daniel Borkmann 
Signed-off-by: Sasha Levin