Although audit_watch_handle_event() can handle FS_UNMOUNT event, it is
not part of AUDIT_FS_WATCH mask and thus such event never gets to
audit_watch_handle_event(). Thus fsnotify marks are deleted by fsnotify
subsystem on unmount without audit being notified about that which leads
to a strange state of existing audit rules with dead fsnotify marks.
Add FS_UNMOUNT to the mask of events to be received so that audit can
clean up its state accordingly.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Paul Moore <paul@paul-moore.com>
audit_remove_watch_rule() drops watch's reference to parent but then
continues to work with it. That is not safe as parent can get freed once
we drop our reference. The following is a trivial reproducer:
mount -o loop image /mnt
touch /mnt/file
auditctl -w /mnt/file -p wax
umount /mnt
auditctl -D
<crash in fsnotify_destroy_mark()>
Grab our own reference in audit_remove_watch_rule() earlier to make sure
mark does not get freed under us.
CC: stable@vger.kernel.org
Reported-by: Tony Jones <tonyj@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Tested-by: Tony Jones <tonyj@suse.de>
Signed-off-by: Paul Moore <paul@paul-moore.com>
When the auditd connection is reset, either intentionally or due to
a failure, any records that were in the main backlog queue would not
be sent in a multicast broadcast. This patch fixes this problem by
not flushing the main backlog queue on a connection reset, the main
kauditd_thread() will take care of that normally.
Resolves: https://github.com/linux-audit/audit-kernel/issues/41
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Originally reported by Adam and Dusty, it appears we have a small
race window in kauditd_thread(), as documented in the Fedora BZ:
* https://bugzilla.redhat.com/show_bug.cgi?id=1459326#c35
"This issue is partly due to the read-copy nature of RCU, and
partly due to how we sync the auditd_connection state across
kauditd_thread and the audit control channel. The kauditd_thread
thread is always running so it can service the record queues and
emit the multicast messages, if it happens to be just past the
"main_queue" label, but before the "if (sk == NULL || ...)"
if-statement which calls auditd_reset() when the new auditd
connection is registered it could end up resetting the auditd
connection, regardless of if it is valid or not. This is a rather
small window and the variable nature of multi-core scheduling
explains why this is proving rather difficult to reproduce."
The fix is to have functions only call auditd_reset() when they
believe that the kernel/auditd connection is still valid, e.g.
non-NULL, and to have these callers pass their local copy of the
auditd_connection pointer to auditd_reset() where it can be compared
with the current connection state before resetting. If the caller
has a stale state tracking pointer then the reset is ignored.
We also make a small change to kauditd_thread() so that if the
kernel/auditd connection is dead we skip the retry queue and send the
records straight to the hold queue. This is necessary as we used to
rely on auditd_reset() to occasionally purge the retry queue but we
are going to be calling the reset function much less now and we want
to make sure the retry queue doesn't grow unbounded.
Reported-by: Adam Williamson <awilliam@redhat.com>
Reported-by: Dusty Mabe <dustymabe@redhat.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Fixed checkpatch.pl warnings of "function definition argument FOO
should also have an identifier name"
Signed-off-by: Derek Robson <robsonde@gmail.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Capabilities were augmented to include ambient capabilities in v4.3
commit 58319057b7 ("capabilities: ambient capabilities").
Add ambient capabilities to the audit BPRM_FCAPS and CAPSET records.
The record contains fields "old_pp", "old_pi", "old_pe", "new_pp",
"new_pi", "new_pe" so in keeping with the previous record
normalizations, change the "new_*" variants to simply drop the "new_"
prefix.
A sample of the replaced BPRM_FCAPS record:
RAW: type=BPRM_FCAPS msg=audit(1491468034.252:237): fver=2
fp=0000000000200000 fi=0000000000000000 fe=1 old_pp=0000000000000000
old_pi=0000000000000000 old_pe=0000000000000000 old_pa=0000000000000000
pp=0000000000200000 pi=0000000000000000 pe=0000000000200000
pa=0000000000000000
INTERPRET: type=BPRM_FCAPS msg=audit(04/06/2017 04:40:34.252:237):
fver=2 fp=sys_admin fi=none fe=chown old_pp=none old_pi=none
old_pe=none old_pa=none pp=sys_admin pi=none pe=sys_admin pa=none
A sample of the replaced CAPSET record:
RAW: type=CAPSET msg=audit(1491469502.371:242): pid=833
cap_pi=0000003fffffffff cap_pp=0000003fffffffff cap_pe=0000003fffffffff
cap_pa=0000000000000000
INTERPRET: type=CAPSET msg=audit(04/06/2017 05:05:02.371:242) : pid=833
cap_pi=chown,dac_override,dac_read_search,fowner,fsetid,kill,
setgid,setuid,setpcap,linux_immutable,net_bind_service,net_broadcast,
net_admin,net_raw,ipc_lock,ipc_owner,sys_module,sys_rawio,sys_chroot,
sys_ptrace,sys_pacct,sys_admin,sys_boot,sys_nice,sys_resource,sys_time,
sys_tty_config,mknod,lease,audit_write,audit_control,setfcap,
mac_override,mac_admin,syslog,wake_alarm,block_suspend,audit_read
cap_pp=chown,dac_override,dac_read_search,fowner,fsetid,kill,setgid,
setuid,setpcap,linux_immutable,net_bind_service,net_broadcast,
net_admin,net_raw,ipc_lock,ipc_owner,sys_module,sys_rawio,sys_chroot,
sys_ptrace,sys_pacct,sys_admin,sys_boot,sys_nice,sys_resource,
sys_time,sys_tty_config,mknod,lease,audit_write,audit_control,setfcap,
mac_override,mac_admin,syslog,wake_alarm,block_suspend,audit_read
cap_pe=chown,dac_override,dac_read_search,fowner,fsetid,kill,setgid,
setuid,setpcap,linux_immutable,net_bind_service,net_broadcast,
net_admin,net_raw,ipc_lock,ipc_owner,sys_module,sys_rawio,sys_chroot,
sys_ptrace,sys_pacct,sys_admin,sys_boot,sys_nice,sys_resource,
sys_time,sys_tty_config,mknod,lease,audit_write,audit_control,setfcap,
mac_override,mac_admin,syslog,wake_alarm,block_suspend,audit_read
cap_pa=none
See: https://github.com/linux-audit/audit-kernel/issues/40
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
The cap_* fields swing in and out of PATH records.
If no capabilities are set, the cap_* fields are completely missing and when
one of the cap_fi or cap_fp values is empty, that field is omitted.
Original:
type=PATH msg=audit(04/20/2017 12:17:11.222:193) : item=1 name=/lib64/ld-linux-x86-64.so.2 inode=787694 dev=08:03 mode=file,755 ouid=root ogid=root rdev=00:00 obj=system_u:object_r:ld_so_t:s0 nametype=NORMAL
type=PATH msg=audit(04/20/2017 12:17:11.222:193) : item=0 name=/home/sleep inode=1319469 dev=08:03 mode=file,suid,755 ouid=root ogid=root rdev=00:00 obj=system_u:object_r:bin_t:s0 nametype=NORMAL cap_fp=sys_admin cap_fe=1 cap_fver=2
Normalize the PATH record by always printing all 4 cap_* fields.
Fixed:
type=PATH msg=audit(04/20/2017 13:01:31.679:201) : item=1 name=/lib64/ld-linux-x86-64.so.2 inode=787694 dev=08:03 mode=file,755 ouid=root ogid=root rdev=00:00 obj=system_u:object_r:ld_so_t:s0 nametype=NORMAL cap_fp=none cap_fi=none cap_fe=0 cap_fver=0
type=PATH msg=audit(04/20/2017 13:01:31.679:201) : item=0 name=/home/sleep inode=1319469 dev=08:03 mode=file,suid,755 ouid=root ogid=root rdev=00:00 obj=system_u:object_r:bin_t:s0 nametype=NORMAL cap_fp=sys_admin cap_fi=none cap_fe=1 cap_fver=2
See: https://github.com/linux-audit/audit-kernel/issues/42
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Cong Wang correctly pointed out that the RCU read locking of the
auditd_connection struct was wrong, this patch correct this by
adopting a more traditional, and correct RCU locking model.
This patch is heavily based on an earlier prototype by Cong Wang.
Cc: <stable@vger.kernel.org> # 4.11.x-
Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
The audit subsystem implemented its own buffer cache mechanism which
is a bit silly these days when we could use the kmem_cache construct.
Some credit is due to Florian Westphal for originally proposing that
we remove the audit cache implementation in favor of simple
kmalloc()/kfree() calls, but I would rather have a dedicated slab
cache to ease debugging and future stats/performance work.
Cc: Florian Westphal <fw@strlen.de>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
struct timespec is not y2038 safe.
Audit timestamps are recorded in string format into
an audit buffer for a given context.
These mark the entry timestamps for the syscalls.
Use y2038 safe struct timespec64 to represent the times.
The log strings can handle this transition as strings can
hold upto 1024 characters.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
This is arguably the right thing to do, and will make it easier when
we start supporting multiple audit daemons in different namespaces.
Signed-off-by: Paul Moore <paul@paul-moore.com>
We were setting the portid incorrectly in the netlink message headers,
fix that to always be 0 (nlmsg_pid = 0).
Signed-off-by: Paul Moore <paul@paul-moore.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
There is no reason to have both of these functions, combine the two.
Signed-off-by: Paul Moore <paul@paul-moore.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
[PM: fix subject line, add #include]
Signed-off-by: Paul Moore <paul@paul-moore.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
[PM: fix subject line, add #include]
Signed-off-by: Paul Moore <paul@paul-moore.com>
The excess ; after the closing parenthesis is just code-noise it has no
and can be removed.
Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
[PM: tweaked subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
The excess ; after the closing parenthesis is just code-noise it has no
and can be removed.
Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
[PM: tweaked subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
The excess ; after the closing parenthesis is just code-noise it has no
and can be removed.
Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
[PM: tweak subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
irq_time_read() returns the irqtime minus the ksoftirqd time. This
is necessary because irq_time_read() is used to substract the IRQ time
from the sum_exec_runtime of a task. If we were to include the softirq
time of ksoftirqd, this task would substract its own CPU time everytime
it updates ksoftirqd->sum_exec_runtime which would therefore never
progress.
But this behaviour got broken by:
a499a5a14d ("sched/cputime: Increment kcpustat directly on irqtime account")
... which now includes ksoftirqd softirq time in the time returned by
irq_time_read().
This has resulted in wrong ksoftirqd cputime reported to userspace
through /proc/stat and thus "top" not showing ksoftirqd when it should
after intense networking load.
ksoftirqd->stime happens to be correct but it gets scaled down by
sum_exec_runtime through task_cputime_adjusted().
To fix this, just account the strict IRQ time in a separate counter and
use it to report the IRQ time.
Reported-and-tested-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1493129448-5356-1-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull irq fix from Thomas Gleixner:
"The (hopefully) final fix for the irq affinity spreading logic"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/affinity: Fix calculating vectors to assign
One is a race condition when enabling the snapshot function probe
trigger. It enables the probe before allocating the snapshot, and
if the probe triggers first, it stops tracing with a warning that
the snapshot buffer was not allocated.
The seconds is that the snapshot file should show how to use it when
it is empty. But a bug fix from long ago broke the "is empty" test
and the snapshot file no longer displays the help message.
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Merge tag 'trace-v4.11-rc5-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull two more ftrace fixes from Steven Rostedt:
"While continuing my development, I uncovered two more small bugs.
One is a race condition when enabling the snapshot function probe
trigger. It enables the probe before allocating the snapshot, and if
the probe triggers first, it stops tracing with a warning that the
snapshot buffer was not allocated.
The seconds is that the snapshot file should show how to use it when
it is empty. But a bug fix from long ago broke the "is empty" test and
the snapshot file no longer displays the help message"
* tag 'trace-v4.11-rc5-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ring-buffer: Have ring_buffer_iter_empty() return true when empty
tracing: Allocate the snapshot buffer before enabling probe
The vectors_per_node is calculated from the remaining available vectors.
The current vector starts after pre_vectors, so we need to subtract that
from the current to properly account for the number of remaining vectors
to assign.
Fixes: 3412386b53 ("irq/affinity: Fix extra vecs calculation")
Reported-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Link: http://lkml.kernel.org/r/1492645870-13019-1-git-send-email-keith.busch@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
I noticed that reading the snapshot file when it is empty no longer gives a
status. It suppose to show the status of the snapshot buffer as well as how
to allocate and use it. For example:
># cat snapshot
# tracer: nop
#
#
# * Snapshot is allocated *
#
# Snapshot commands:
# echo 0 > snapshot : Clears and frees snapshot buffer
# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.
# Takes a snapshot of the main buffer.
# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)
# (Doesn't have to be '2' works with any number that
# is not a '0' or '1')
But instead it just showed an empty buffer:
># cat snapshot
# tracer: nop
#
# entries-in-buffer/entries-written: 0/0 #P:4
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
What happened was that it was using the ring_buffer_iter_empty() function to
see if it was empty, and if it was, it showed the status. But that function
was returning false when it was empty. The reason was that the iter header
page was on the reader page, and the reader page was empty, but so was the
buffer itself. The check only tested to see if the iter was on the commit
page, but the commit page was no longer pointing to the reader page, but as
all pages were empty, the buffer is also.
Cc: stable@vger.kernel.org
Fixes: 651e22f270 ("ring-buffer: Always reset iterator to reader page")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Currently the snapshot trigger enables the probe and then allocates the
snapshot. If the probe triggers before the allocation, it could cause the
snapshot to fail and turn tracing off. It's best to allocate the snapshot
buffer first, and then enable the trigger. If something goes wrong in the
enabling of the trigger, the snapshot buffer is still allocated, but it can
also be freed by the user by writting zero into the snapshot buffer file.
Also add a check of the return status of alloc_snapshot().
Cc: stable@vger.kernel.org
Fixes: 77fd5c15e3 ("tracing: Add snapshot trigger to function probes")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull sparc fixes from David Miller:
"Two Sparc bug fixes from Daniel Jordan and Nitin Gupta"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc64: Fix hugepage page table free
sparc64: Use LOCKDEP_SMALL, not PROVE_LOCKING_SMALL
Pull networking fixes from David Miller:
1) BPF tail call handling bug fixes from Daniel Borkmann.
2) Fix allowance of too many rx queues in sfc driver, from Bert
Kenward.
3) Non-loopback ipv6 packets claiming src of ::1 should be dropped,
from Florian Westphal.
4) Statistics requests on KSZ9031 can crash, fix from Grygorii
Strashko.
5) TX ring handling fixes in mediatek driver, from Sean Wang.
6) ip_ra_control can deadlock, fix lock acquisition ordering to fix,
from Cong WANG.
7) Fix use after free in ip_recv_error(), from Willem de Buijn.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
bpf: fix checking xdp_adjust_head on tail calls
bpf: fix cb access in socket filter programs on tail calls
ipv6: drop non loopback packets claiming to originate from ::1
net: ethernet: mediatek: fix inconsistency of port number carried in TXD
net: ethernet: mediatek: fix inconsistency between TXD and the used buffer
net: phy: micrel: fix crash when statistic requested for KSZ9031 phy
net: vrf: Fix setting NLM_F_EXCL flag when adding l3mdev rule
net: thunderx: Fix set_max_bgx_per_node for 81xx rgx
net-timestamp: avoid use-after-free in ip_recv_error
ipv4: fix a deadlock in ip_ra_control
sfc: limit the number of receive queues
CONFIG_PROVE_LOCKING_SMALL shrinks the memory usage of lockdep so the
kernel text, data, and bss fit in the required 32MB limit, but this
option is not set for every config that enables lockdep.
A 4.10 kernel fails to boot with the console output
Kernel: Using 8 locked TLB entries for main kernel image.
hypervisor_tlb_lock[2000000:0:8000000071c007c3:1]: errors with f
Program terminated
with these config options
CONFIG_LOCKDEP=y
CONFIG_LOCK_STAT=y
CONFIG_PROVE_LOCKING=n
To fix, rename CONFIG_PROVE_LOCKING_SMALL to CONFIG_LOCKDEP_SMALL, and
enable this option with CONFIG_LOCKDEP=y so we get the reduced memory
usage every time lockdep is turned on.
Tested that CONFIG_LOCKDEP_SMALL is set to 'y' if and only if
CONFIG_LOCKDEP is set to 'y'. When other lockdep-related config options
that select CONFIG_LOCKDEP are enabled (e.g. CONFIG_LOCK_STAT or
CONFIG_PROVE_LOCKING), verified that CONFIG_LOCKDEP_SMALL is also
enabled.
Fixes: e6b5f1be7a ("config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
a pid filter to function tracing in an instance, and then freeing
the instance.
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Merge tag 'trace-v4.11-rc5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull ftrace fix from Steven Rostedt:
"Namhyung Kim discovered a use after free bug. It has to do with adding
a pid filter to function tracing in an instance, and then freeing the
instance"
* tag 'trace-v4.11-rc5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Fix function pid filter on instances
When function tracer has a pid filter, it adds a probe to sched_switch
to track if current task can be ignored. The probe checks the
ftrace_ignore_pid from current tr to filter tasks. But it misses to
delete the probe when removing an instance so that it can cause a crash
due to the invalid tr pointer (use-after-free).
This is easily reproducible with the following:
# cd /sys/kernel/debug/tracing
# mkdir instances/buggy
# echo $$ > instances/buggy/set_ftrace_pid
# rmdir instances/buggy
============================================================================
BUG: KASAN: use-after-free in ftrace_filter_pid_sched_switch_probe+0x3d/0x90
Read of size 8 by task kworker/0:1/17
CPU: 0 PID: 17 Comm: kworker/0:1 Tainted: G B 4.11.0-rc3 #198
Call Trace:
dump_stack+0x68/0x9f
kasan_object_err+0x21/0x70
kasan_report.part.1+0x22b/0x500
? ftrace_filter_pid_sched_switch_probe+0x3d/0x90
kasan_report+0x25/0x30
__asan_load8+0x5e/0x70
ftrace_filter_pid_sched_switch_probe+0x3d/0x90
? fpid_start+0x130/0x130
__schedule+0x571/0xce0
...
To fix it, use ftrace_clear_pids() to unregister the probe. As
instance_rmdir() already updated ftrace codes, it can just free the
filter safely.
Link: http://lkml.kernel.org/r/20170417024430.21194-2-namhyung@kernel.org
Fixes: 0c8916c342 ("tracing: Add rmdir to remove multibuffer instances")
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Commit 17bedab272 ("bpf: xdp: Allow head adjustment in XDP prog")
added the xdp_adjust_head bit to the BPF prog in order to tell drivers
that the program that is to be attached requires support for the XDP
bpf_xdp_adjust_head() helper such that drivers not supporting this
helper can reject the program. There are also drivers that do support
the helper, but need to check for xdp_adjust_head bit in order to move
packet metadata prepended by the firmware away for making headroom.
For these cases, the current check for xdp_adjust_head bit is insufficient
since there can be cases where the program itself does not use the
bpf_xdp_adjust_head() helper, but tail calls into another program that
uses bpf_xdp_adjust_head(). As such, the xdp_adjust_head bit is still
set to 0. Since the first program has no control over which program it
calls into, we need to assume that bpf_xdp_adjust_head() helper is used
upon tail calls. Thus, for the very same reasons in cb_access, set the
xdp_adjust_head bit to 1 when the main program uses tail calls.
Fixes: 17bedab272 ("bpf: xdp: Allow head adjustment in XDP prog")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit ff936a04e5 ("bpf: fix cb access in socket filter programs")
added a fix for socket filter programs such that in i) AF_PACKET the
20 bytes of skb->cb[] area gets zeroed before use in order to not leak
data, and ii) socket filter programs attached to TCP/UDP sockets need
to save/restore these 20 bytes since they are also used by protocol
layers at that time.
The problem is that bpf_prog_run_save_cb() and bpf_prog_run_clear_cb()
only look at the actual attached program to determine whether to zero
or save/restore the skb->cb[] parts. There can be cases where the
actual attached program does not access the skb->cb[], but the program
tail calls into another program which does access this area. In such
a case, the zero or save/restore is currently not performed.
Since the programs we tail call into are unknown at verification time
and can dynamically change, we need to assume that whenever the attached
program performs a tail call, that later programs could access the
skb->cb[], and therefore we need to always set cb_access to 1.
Fixes: ff936a04e5 ("bpf: fix cb access in socket filter programs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull cgroup fix from Tejun Heo:
"Unfortunately, the commit to fix the cgroup mount race in the previous
pull request can lead to hangs.
The original bug has been around for a while and isn't too likely to
be triggered in usual use cases. Revert the commit for now"
* 'for-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
Revert "cgroup: avoid attaching a cgroup root to two different superblocks"
bug. This bug has been there sinc function tracing was added way back
when. But my new development depends on this bug being fixed, and it
should be fixed regardless as it causes ftrace to disable itself when
triggered, and a reboot is required to enable it again.
The bug is that the function probe does not disable itself properly
if there's another probe of its type still enabled. For example:
# cd /sys/kernel/debug/tracing
# echo schedule:traceoff > set_ftrace_filter
# echo do_IRQ:traceoff > set_ftrace_filter
# echo \!do_IRQ:traceoff > /debug/tracing/set_ftrace_filter
# echo do_IRQ:traceoff > set_ftrace_filter
The above registers two traceoff probes (one for schedule and one for
do_IRQ, and then removes do_IRQ. But since there still exists one for
schedule, it is not done properly. When adding do_IRQ back, the breakage
in the accounting is noticed by the ftrace self tests, and it causes
a warning and disables ftrace.
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Merge tag 'trace-v4.11-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull ftrace fix from Steven Rostedt:
"While rewriting the function probe code, I stumbled over a long
standing bug. This bug has been there sinc function tracing was added
way back when. But my new development depends on this bug being fixed,
and it should be fixed regardless as it causes ftrace to disable
itself when triggered, and a reboot is required to enable it again.
The bug is that the function probe does not disable itself properly if
there's another probe of its type still enabled. For example:
# cd /sys/kernel/debug/tracing
# echo schedule:traceoff > set_ftrace_filter
# echo do_IRQ:traceoff > set_ftrace_filter
# echo \!do_IRQ:traceoff > /debug/tracing/set_ftrace_filter
# echo do_IRQ:traceoff > set_ftrace_filter
The above registers two traceoff probes (one for schedule and one for
do_IRQ, and then removes do_IRQ.
But since there still exists one for schedule, it is not done
properly. When adding do_IRQ back, the breakage in the accounting is
noticed by the ftrace self tests, and it causes a warning and disables
ftrace"
* tag 'trace-v4.11-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Fix removing of second function probe
This reverts commit bfb0b80db5.
Andrei reports CRIU test hangs with the patch applied. The bug fixed
by the patch isn't too likely to trigger in actual uses. Revert the
patch for now.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Andrei Vagin <avagin@virtuozzo.com>
Link: http://lkml.kernel.org/r/20170414232737.GC20350@outlook.office365.com
Pull networking fixes from David Miller:
"Things seem to be settling down as far as networking is concerned,
let's hope this trend continues...
1) Add iov_iter_revert() and use it to fix the behavior of
skb_copy_datagram_msg() et al., from Al Viro.
2) Fix the protocol used in the synthetic SKB we cons up for the
purposes of doing a simulated route lookup for RTM_GETROUTE
requests. From Florian Larysch.
3) Don't add noop_qdisc to the per-device qdisc hashes, from Cong
Wang.
4) Don't call netdev_change_features with the team lock held, from
Xin Long.
5) Revert TCP F-RTO extension to catch more spurious timeouts because
it interacts very badly with some middle-boxes. From Yuchung
Cheng.
6) Fix the loss of error values in l2tp {s,g}etsockopt calls, from
Guillaume Nault.
7) ctnetlink uses bit positions where it should be using bit masks,
fix from Liping Zhang.
8) Missing RCU locking in netfilter helper code, from Gao Feng.
9) Avoid double frees and use-after-frees in tcp_disconnect(), from
Eric Dumazet.
10) Don't do a changelink before we register the netdevice in
bridging, from Ido Schimmel.
11) Lock the ipv6 device address list properly, from Rabin Vincent"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (29 commits)
netfilter: ipt_CLUSTERIP: Fix wrong conntrack netns refcnt usage
netfilter: nft_hash: do not dump the auto generated seed
drivers: net: usb: qmi_wwan: add QMI_QUIRK_SET_DTR for Telit PID 0x1201
ipv6: Fix idev->addr_list corruption
net: xdp: don't export dev_change_xdp_fd()
bridge: netlink: register netdevice before executing changelink
bridge: implement missing ndo_uninit()
bpf: reference may_access_skb() from __bpf_prog_run()
tcp: clear saved_syn in tcp_disconnect()
netfilter: nf_ct_expect: use proper RCU list traversal/update APIs
netfilter: ctnetlink: skip dumping expect when nfct_help(ct) is NULL
netfilter: make it safer during the inet6_dev->addr_list traversal
netfilter: ctnetlink: make it safer when checking the ct helper name
netfilter: helper: Add the rcu lock when call __nf_conntrack_helper_find
netfilter: ctnetlink: using bit to represent the ct event
netfilter: xt_TCPMSS: add more sanity tests on tcph->doff
net: tcp: Increase TCP_MIB_OUTRSTS even though fail to alloc skb
l2tp: don't mask errors in pppol2tp_getsockopt()
l2tp: don't mask errors in pppol2tp_setsockopt()
tcp: restrict F-RTO to work-around broken middle-boxes
...
Pull irq fixes from Thomas Gleixner:
"The irq department provides:
- two fixes for the CPU affinity spread infrastructure to prevent
unbalanced spreading in corner cases which leads to horrible
performance, because interrupts are rather aggregated than spread
- add a missing spinlock initializer in the imx-gpcv2 init code"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/irq-imx-gpcv2: Fix spinlock initialization
irq/affinity: Fix extra vecs calculation
irq/affinity: Fix CPU spread for unbalanced nodes
This fixes a math error calculating the extra_vecs. The error assumed
only 1 cpu per vector, but the value needs to account for the actual
number of cpus per vector in order to get the correct remainder for
extra CPU assignment.
Fixes: 7bf8222b9b ("irq/affinity: Fix CPU spread for unbalanced nodes")
Reported-by: Xiaolong Ye <xiaolong.ye@intel.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Link: http://lkml.kernel.org/r/1492104492-19943-1-git-send-email-keith.busch@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pull audit fix from Paul Moore:
"One more small audit fix, this should be the last for v4.11.
Seth Forshee noticed a problem where the audit retry queue wasn't
being flushed properly when audit was enabled and the audit daemon
wasn't running; this patches fixes the problem (see the commit
description for more details on the change).
Both Seth and I have tested this and everything looks good"
* 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit:
audit: make sure we don't let the retry queue grow without bounds
Pull cgroup fixes from Tejun Heo:
"This contains fixes for two long standing subtle bugs:
- kthread_bind() on a new kthread binds it to specific CPUs and
prevents userland from messing with the affinity or cgroup
membership. Unfortunately, for cgroup membership, there's a window
between kthread creation and kthread_bind*() invocation where the
kthread can be moved into a non-root cgroup by userland.
Depending on what controllers are in effect, this can assign the
kthread unexpected attributes. For example, in the reported case,
workqueue workers ended up in a non-root cpuset cgroups and had
their CPU affinities overridden. This broke workqueue invariants
and led to workqueue stalls.
Fixed by closing the window between kthread creation and
kthread_bind() as suggested by Oleg.
- There was a bug in cgroup mount path which could allow two
competing mount attempts to attach the same cgroup_root to two
different superblocks.
This was caused by mishandling return value from kernfs_pin_sb().
Fixed"
* 'for-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: avoid attaching a cgroup root to two different superblocks
cgroup, kthread: close race window where new kthreads can be migrated to non-root cgroups
It took me quite some time to figure out how this was linked,
so in order to save the next person the effort of finding it
add a comment in __bpf_prog_run() that indicates what exactly
determines that a program can access the ctx == skb.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Run this:
touch file0
for ((; ;))
{
mount -t cpuset xxx file0
}
And this concurrently:
touch file1
for ((; ;))
{
mount -t cpuset xxx file1
}
We'll trigger a warning like this:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4675 at lib/percpu-refcount.c:317 percpu_ref_kill_and_confirm+0x92/0xb0
percpu_ref_kill_and_confirm called more than once on css_release!
CPU: 1 PID: 4675 Comm: mount Not tainted 4.11.0-rc5+ #5
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
Call Trace:
dump_stack+0x63/0x84
__warn+0xd1/0xf0
warn_slowpath_fmt+0x5f/0x80
percpu_ref_kill_and_confirm+0x92/0xb0
cgroup_kill_sb+0x95/0xb0
deactivate_locked_super+0x43/0x70
deactivate_super+0x46/0x60
...
---[ end trace a79f61c2a2633700 ]---
Here's a race:
Thread A Thread B
cgroup1_mount()
# alloc a new cgroup root
cgroup_setup_root()
cgroup1_mount()
# no sb yet, returns NULL
kernfs_pin_sb()
# but succeeds in getting the refcnt,
# so re-use cgroup root
percpu_ref_tryget_live()
# alloc sb with cgroup root
cgroup_do_mount()
cgroup_kill_sb()
# alloc another sb with same root
cgroup_do_mount()
cgroup_kill_sb()
We end up using the same cgroup root for two different superblocks,
so percpu_ref_kill() will be called twice on the same root when the
two superblocks are destroyed.
We should fix to make sure the superblock pinning is really successful.
Cc: stable@vger.kernel.org # 3.16+
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The retry queue is intended to provide a temporary buffer in the case
of transient errors when communicating with auditd, it is not meant
as a long life queue, that functionality is provided by the hold
queue.
This patch fixes a problem identified by Seth where the retry queue
could grow uncontrollably if an auditd instance did not connect to
the kernel to drain the queues. This commit fixes this by doing the
following:
* Make sure we always call auditd_reset() if we decide the connection
with audit is really dead. There were some cases in
kauditd_hold_skb() where we did not reset the connection, this patch
relocates the reset calls to kauditd_thread() so all the error
conditions are caught and the connection reset. As a side effect,
this means we could move auditd_reset() and get rid of the forward
definition at the top of kernel/audit.c.
* We never checked the status of the auditd connection when
processing the main audit queue which meant that the retry queue
could grow unchecked. This patch adds a call to auditd_reset()
after the main queue has been processed if auditd is not connected,
the auditd_reset() call will make sure the retry and hold queues are
correctly managed/flushed so that the retry queue remains reasonable.
Cc: <stable@vger.kernel.org> # 4.10.x-: 5b52330bbf
Reported-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Currently, inputting the following command will succeed but actually the
value will be truncated:
# echo 0x12ffffffff > /proc/sys/net/ipv4/tcp_notsent_lowat
This is not friendly to the user, so instead, we should report error
when the value is larger than UINT_MAX.
Fixes: e7d316a02f ("sysctl: handle error writing UINT_MAX to u32 fields")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Cc: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull audit cleanup from Paul Moore:
"A week later than I had hoped, but as promised, here is the audit
uninline-fix we talked about during the last audit pull request.
The patch is slightly different than what we originally discussed as
it made more sense to keep the audit_signal_info() function in
auditsc.c rather than move it and bunch of other related
variables/definitions into audit.c/audit.h.
At some point in the future I need to look at how the audit code is
organized across kernel/audit*, I suspect we could do things a bit
better, but it doesn't seem like a -rc release is a good place for
that ;)
Regardless, this patch passes our tests without problem and looks good
for v4.11"
* 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit:
audit: move audit_signal_info() into kernel/auditsc.c
In PT_SEIZED + LISTEN mode STOP/CONT signals cause a wakeup against
__TASK_TRACED. If this races with the ptrace_unfreeze_traced at the end
of a PTRACE_LISTEN, this can wake the task /after/ the check against
__TASK_TRACED, but before the reset of state to TASK_TRACED. This
causes it to instead clobber TASK_WAKING, allowing a subsequent wakeup
against TRACED while the task is still on the rq wake_list, corrupting
it.
Oleg said:
"The kernel can crash or this can lead to other hard-to-debug problems.
In short, "task->state = TASK_TRACED" in ptrace_unfreeze_traced()
assumes that nobody else can wake it up, but PTRACE_LISTEN breaks the
contract. Obviusly it is very wrong to manipulate task->state if this
task is already running, or WAKING, or it sleeps again"
[akpm@linux-foundation.org: coding-style fixes]
Fixes: 9899d11f ("ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL")
Link: http://lkml.kernel.org/r/xm26y3vfhmkp.fsf_-_@bsegall-linux.mtv.corp.google.com
Signed-off-by: Ben Segall <bsegall@google.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I saw some very confusing sysctl output on my system:
# cat /proc/sys/net/core/xfrm_aevent_rseqth
-2
# cat /proc/sys/net/core/xfrm_aevent_etime
-10
# cat /proc/sys/net/ipv4/tcp_notsent_lowat
-4294967295
Because we forget to set the *negp flag in proc_douintvec, so it will
become a garbage value.
Since the value related to proc_douintvec is always an unsigned integer,
so we can set *negp to false explictily to fix this issue.
Fixes: e7d316a02f ("sysctl: handle error writing UINT_MAX to u32 fields")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Cc: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If for some unknown reason, the kthread that is created fails to be
created, the return from kthread_create() is an PTR_ERR and not a NULL.
The test incorrectly checks for NULL instead of an error.
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Merge tag 'trace-v4.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"Wei Yongjun fixed a long standing bug in the ring buffer startup test.
If for some unknown reason, the kthread that is created fails to be
created, the return from kthread_create() is an PTR_ERR and not a
NULL. The test incorrectly checks for NULL instead of an error"
* tag 'trace-v4.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ring-buffer: Fix return value check in test_ringbuffer()
