Merge misc fixes from Andrew Morton:
"9 patches.
Subsystems affected by this patch series: mm (kfence, mempolicy,
memory-failure, pagemap, pagealloc, damon, and memory-failure),
core-kernel, and MAINTAINERS"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page()
mm/damon/dbgfs: protect targets destructions with kdamond_lock
mm/page_alloc: fix __alloc_size attribute for alloc_pages_exact_nid
mm: delete unsafe BUG from page_cache_add_speculative()
mm, hwpoison: fix condition in free hugetlb page path
MAINTAINERS: mark more list instances as moderated
kernel/crash_core: suppress unknown crashkernel parameter warning
mm: mempolicy: fix THP allocations escaping mempolicy restrictions
kfence: fix memory leak when cat kfence objects
When booting with crashkernel= on the kernel command line a warning
similar to
Kernel command line: ro console=ttyS0 crashkernel=256M
Unknown kernel command line parameters "crashkernel=256M", will be passed to user space.
is printed.
This comes from crashkernel= being parsed independent from the kernel
parameter handling mechanism. So the code in init/main.c doesn't know
that crashkernel= is a valid kernel parameter and prints this incorrect
warning.
Suppress the warning by adding a dummy early_param handler for
crashkernel=.
Link: https://lkml.kernel.org/r/20211208133443.6867-1-prudo@redhat.com
Fixes: 86d1919a4f ("init: print out unknown kernel parameters")
Signed-off-by: Philipp Rudo <prudo@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Andrew Halaney <ahalaney@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull ucount fix from Eric Biederman:
"This fixes a silly logic bug in the ucount rlimits code, where it was
comparing against the wrong limit"
* 'ucount-rlimit-fixes-for-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
ucounts: Fix rlimit max values check
Pull timer fix from Borislav Petkov:
- Make sure the CLOCK_REALTIME to CLOCK_MONOTONIC offset is never
positive
* tag 'timers_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping: Really make sure wall_to_monotonic isn't positive
Pull locking fix from Borislav Petkov:
- Fix the rtmutex condition checking when the optimistic spinning of a
waiter needs to be terminated
* tag 'locking_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/rtmutex: Fix incorrect condition in rtmutex_spin_on_owner()
Pull signal handlign fix from Borislav Petkov:
- Prevent lock contention on the new sigaltstack lock on the
common-case path, when no changes have been made to the alternative
signal stack.
* tag 'core_urgent_for_v5.16_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
signal: Skip the altstack update when not needed
Even after commit e1d7ba8735 ("time: Always make sure wall_to_monotonic
isn't positive") it is still possible to make wall_to_monotonic positive
by running the following code:
int main(void)
{
struct timespec time;
clock_gettime(CLOCK_MONOTONIC, &time);
time.tv_nsec = 0;
clock_settime(CLOCK_REALTIME, &time);
return 0;
}
The reason is that the second parameter of timespec64_compare(), ts_delta,
may be unnormalized because the delta is calculated with an open coded
substraction which causes the comparison of tv_sec to yield the wrong
result:
wall_to_monotonic = { .tv_sec = -10, .tv_nsec = 900000000 }
ts_delta = { .tv_sec = -9, .tv_nsec = -900000000 }
That makes timespec64_compare() claim that wall_to_monotonic < ts_delta,
but actually the result should be wall_to_monotonic > ts_delta.
After normalization, the result of timespec64_compare() is correct because
the tv_sec comparison is not longer misleading:
wall_to_monotonic = { .tv_sec = -10, .tv_nsec = 900000000 }
ts_delta = { .tv_sec = -10, .tv_nsec = 100000000 }
Use timespec64_sub() to ensure that ts_delta is normalized, which fixes the
issue.
Fixes: e1d7ba8735 ("time: Always make sure wall_to_monotonic isn't positive")
Signed-off-by: Yu Liao <liaoyu15@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211213135727.1656662-1-liaoyu15@huawei.com
Pull audit fix from Paul Moore:
"A single patch to fix a problem where the audit queue could grow
unbounded when the audit daemon is forcibly stopped"
* tag 'audit-pr-20211216' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: improve robustness of the audit queue handling
Pull networking fixes from Jakub Kicinski:
"Networking fixes, including fixes from mac80211, wifi, bpf.
Relatively large batches of fixes from BPF and the WiFi stack, calm in
general networking.
Current release - regressions:
- dpaa2-eth: fix buffer overrun when reporting ethtool statistics
Current release - new code bugs:
- bpf: fix incorrect state pruning for <8B spill/fill
- iavf:
- add missing unlocks in iavf_watchdog_task()
- do not override the adapter state in the watchdog task (again)
- mlxsw: spectrum_router: consolidate MAC profiles when possible
Previous releases - regressions:
- mac80211 fixes:
- rate control, avoid driver crash for retransmitted frames
- regression in SSN handling of addba tx
- a memory leak where sta_info is not freed
- marking TX-during-stop for TX in in_reconfig, prevent stall
- cfg80211: acquire wiphy mutex on regulatory work
- wifi drivers: fix build regressions and LED config dependency
- virtio_net: fix rx_drops stat for small pkts
- dsa: mv88e6xxx: unforce speed & duplex in mac_link_down()
Previous releases - always broken:
- bpf fixes:
- kernel address leakage in atomic fetch
- kernel address leakage in atomic cmpxchg's r0 aux reg
- signed bounds propagation after mov32
- extable fixup offset
- extable address check
- mac80211:
- fix the size used for building probe request
- send ADDBA requests using the tid/queue of the aggregation
session
- agg-tx: don't schedule_and_wake_txq() under sta->lock, avoid
deadlocks
- validate extended element ID is present
- mptcp:
- never allow the PM to close a listener subflow (null-defer)
- clear 'kern' flag from fallback sockets, prevent crash
- fix deadlock in __mptcp_push_pending()
- inet_diag: fix kernel-infoleak for UDP sockets
- xsk: do not sleep in poll() when need_wakeup set
- smc: avoid very long waits in smc_release()
- sch_ets: don't remove idle classes from the round-robin list
- netdevsim:
- zero-initialize memory for bpf map's value, prevent info leak
- don't let user space overwrite read only (max) ethtool parms
- ixgbe: set X550 MDIO speed before talking to PHY
- stmmac:
- fix null-deref in flower deletion w/ VLAN prio Rx steering
- dwmac-rk: fix oob read in rk_gmac_setup
- ice: time stamping fixes
- systemport: add global locking for descriptor life cycle"
* tag 'net-5.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (89 commits)
bpf, selftests: Fix racing issue in btf_skc_cls_ingress test
selftest/bpf: Add a test that reads various addresses.
bpf: Fix extable address check.
bpf: Fix extable fixup offset.
bpf, selftests: Add test case trying to taint map value pointer
bpf: Make 32->64 bounds propagation slightly more robust
bpf: Fix signed bounds propagation after mov32
sit: do not call ipip6_dev_free() from sit_init_net()
net: systemport: Add global locking for descriptor lifecycle
net/smc: Prevent smc_release() from long blocking
net: Fix double 0x prefix print in SKB dump
virtio_net: fix rx_drops stat for small pkts
dsa: mv88e6xxx: fix debug print for SPEED_UNFORCED
sfc_ef100: potential dereference of null pointer
net: stmmac: dwmac-rk: fix oob read in rk_gmac_setup
net: usb: lan78xx: add Allied Telesis AT29M2-AF
net/packet: rx_owner_map depends on pg_vec
netdevsim: Zero-initialize memory for new map's value in function nsim_bpf_map_alloc
dpaa2-eth: fix ethtool statistics
ixgbe: set X550 MDIO speed before talking to PHY
...
Make the bounds propagation in __reg_assign_32_into_64() slightly more
robust and readable by aligning it similarly as we did back in the
__reg_combine_64_into_32() counterpart. Meaning, only propagate or
pessimize them as a smin/smax pair.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
For the case where both s32_{min,max}_value bounds are positive, the
__reg_assign_32_into_64() directly propagates them to their 64 bit
counterparts, otherwise it pessimises them into [0,u32_max] universe and
tries to refine them later on by learning through the tnum as per comment
in mentioned function. However, that does not always happen, for example,
in mov32 operation we call zext_32_to_64(dst_reg) which invokes the
__reg_assign_32_into_64() as is without subsequent bounds update as
elsewhere thus no refinement based on tnum takes place.
Thus, not calling into the __update_reg_bounds() / __reg_deduce_bounds() /
__reg_bound_offset() triplet as we do, for example, in case of ALU ops via
adjust_scalar_min_max_vals(), will lead to more pessimistic bounds when
dumping the full register state:
Before fix:
0: (b4) w0 = -1
1: R0_w=invP4294967295
(id=0,imm=ffffffff,
smin_value=4294967295,smax_value=4294967295,
umin_value=4294967295,umax_value=4294967295,
var_off=(0xffffffff; 0x0),
s32_min_value=-1,s32_max_value=-1,
u32_min_value=-1,u32_max_value=-1)
1: (bc) w0 = w0
2: R0_w=invP4294967295
(id=0,imm=ffffffff,
smin_value=0,smax_value=4294967295,
umin_value=4294967295,umax_value=4294967295,
var_off=(0xffffffff; 0x0),
s32_min_value=-1,s32_max_value=-1,
u32_min_value=-1,u32_max_value=-1)
Technically, the smin_value=0 and smax_value=4294967295 bounds are not
incorrect, but given the register is still a constant, they break assumptions
about const scalars that smin_value == smax_value and umin_value == umax_value.
After fix:
0: (b4) w0 = -1
1: R0_w=invP4294967295
(id=0,imm=ffffffff,
smin_value=4294967295,smax_value=4294967295,
umin_value=4294967295,umax_value=4294967295,
var_off=(0xffffffff; 0x0),
s32_min_value=-1,s32_max_value=-1,
u32_min_value=-1,u32_max_value=-1)
1: (bc) w0 = w0
2: R0_w=invP4294967295
(id=0,imm=ffffffff,
smin_value=4294967295,smax_value=4294967295,
umin_value=4294967295,umax_value=4294967295,
var_off=(0xffffffff; 0x0),
s32_min_value=-1,s32_max_value=-1,
u32_min_value=-1,u32_max_value=-1)
Without the smin_value == smax_value and umin_value == umax_value invariant
being intact for const scalars, it is possible to leak out kernel pointers
from unprivileged user space if the latter is enabled. For example, when such
registers are involved in pointer arithmtics, then adjust_ptr_min_max_vals()
will taint the destination register into an unknown scalar, and the latter
can be exported and stored e.g. into a BPF map value.
Fixes: 3f50f132d8 ("bpf: Verifier, do explicit ALU32 bounds tracking")
Reported-by: Kuee K1r0a <liulin063@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
If the audit daemon were ever to get stuck in a stopped state the
kernel's kauditd_thread() could get blocked attempting to send audit
records to the userspace audit daemon. With the kernel thread
blocked it is possible that the audit queue could grow unbounded as
certain audit record generating events must be exempt from the queue
limits else the system enter a deadlock state.
This patch resolves this problem by lowering the kernel thread's
socket sending timeout from MAX_SCHEDULE_TIMEOUT to HZ/10 and tweaks
the kauditd_send_queue() function to better manage the various audit
queues when connection problems occur between the kernel and the
audit daemon. With this patch, the backlog may temporarily grow
beyond the defined limits when the audit daemon is stopped and the
system is under heavy audit pressure, but kauditd_thread() will
continue to make progress and drain the queues as it would for other
connection problems. For example, with the audit daemon put into a
stopped state and the system configured to audit every syscall it
was still possible to shutdown the system without a kernel panic,
deadlock, etc.; granted, the system was slow to shutdown but that is
to be expected given the extreme pressure of recording every syscall.
The timeout value of HZ/10 was chosen primarily through
experimentation and this developer's "gut feeling". There is likely
no one perfect value, but as this scenario is limited in scope (root
privileges would be needed to send SIGSTOP to the audit daemon), it
is likely not worth exposing this as a tunable at present. This can
always be done at a later date if it proves necessary.
Cc: stable@vger.kernel.org
Fixes: 5b52330bbf ("audit: fix auditd/kernel connection state tracking")
Reported-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Tested-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
The implementation of BPF_CMPXCHG on a high level has the following parameters:
.-[old-val] .-[new-val]
BPF_R0 = cmpxchg{32,64}(DST_REG + insn->off, BPF_R0, SRC_REG)
`-[mem-loc] `-[old-val]
Given a BPF insn can only have two registers (dst, src), the R0 is fixed and
used as an auxilliary register for input (old value) as well as output (returning
old value from memory location). While the verifier performs a number of safety
checks, it misses to reject unprivileged programs where R0 contains a pointer as
old value.
Through brute-forcing it takes about ~16sec on my machine to leak a kernel pointer
with BPF_CMPXCHG. The PoC is basically probing for kernel addresses by storing the
guessed address into the map slot as a scalar, and using the map value pointer as
R0 while SRC_REG has a canary value to detect a matching address.
Fix it by checking R0 for pointers, and reject if that's the case for unprivileged
programs.
Fixes: 5ffa25502b ("bpf: Add instructions for atomic_[cmp]xchg")
Reported-by: Ryota Shiga (Flatt Security)
Acked-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The change in commit 37086bfdc7 ("bpf: Propagate stack bounds to registers
in atomics w/ BPF_FETCH") around check_mem_access() handling is buggy since
this would allow for unprivileged users to leak kernel pointers. For example,
an atomic fetch/and with -1 on a stack destination which holds a spilled
pointer will migrate the spilled register type into a scalar, which can then
be exported out of the program (since scalar != pointer) by dumping it into
a map value.
The original implementation of XADD was preventing this situation by using
a double call to check_mem_access() one with BPF_READ and a subsequent one
with BPF_WRITE, in both cases passing -1 as a placeholder value instead of
register as per XADD semantics since it didn't contain a value fetch. The
BPF_READ also included a check in check_stack_read_fixed_off() which rejects
the program if the stack slot is of __is_pointer_value() if dst_regno < 0.
The latter is to distinguish whether we're dealing with a regular stack spill/
fill or some arithmetical operation which is disallowed on non-scalars, see
also 6e7e63cbb0 ("bpf: Forbid XADD on spilled pointers for unprivileged
users") for more context on check_mem_access() and its handling of placeholder
value -1.
One minimally intrusive option to fix the leak is for the BPF_FETCH case to
initially check the BPF_READ case via check_mem_access() with -1 as register,
followed by the actual load case with non-negative load_reg to propagate
stack bounds to registers.
Fixes: 37086bfdc7 ("bpf: Propagate stack bounds to registers in atomics w/ BPF_FETCH")
Reported-by: <n4ke4mry@gmail.com>
Acked-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
== Background ==
Support for large, "dynamic" fpstates was recently merged. This
included code to ensure that sigaltstacks are sufficiently sized for
these large states. A new lock was added to remove races between
enabling large features and setting up sigaltstacks.
== Problem ==
The new lock (sigaltstack_lock()) is acquired in the sigreturn path
before restoring the old sigaltstack. Unfortunately, contention on the
new lock causes a measurable signal handling performance regression [1].
However, the common case is that no *changes* are made to the
sigaltstack state at sigreturn.
== Solution ==
do_sigaltstack() acquires sigaltstack_lock() and is used for both
sys_sigaltstack() and restoring the sigaltstack in sys_sigreturn().
Check for changes to the sigaltstack before taking the lock. If no
changes were made, return before acquiring the lock.
This removes lock contention from the common-case sigreturn path.
[1] https://lore.kernel.org/lkml/20211207012128.GA16074@xsang-OptiPlex-9020/
Fixes: 3aac3ebea0 ("x86/signal: Implement sigaltstack size validation")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20211210225503.12734-1-chang.seok.bae@intel.com
Merge misc fixes from Andrew Morton:
"21 patches.
Subsystems affected by this patch series: MAINTAINERS, mailmap, and mm
(mlock, pagecache, damon, slub, memcg, hugetlb, and pagecache)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (21 commits)
mm: bdi: initialize bdi_min_ratio when bdi is unregistered
hugetlbfs: fix issue of preallocation of gigantic pages can't work
mm/memcg: relocate mod_objcg_mlstate(), get_obj_stock() and put_obj_stock()
mm/slub: fix endianness bug for alloc/free_traces attributes
selftests/damon: split test cases
selftests/damon: test debugfs file reads/writes with huge count
selftests/damon: test wrong DAMOS condition ranges input
selftests/damon: test DAMON enabling with empty target_ids case
selftests/damon: skip test if DAMON is running
mm/damon/vaddr-test: remove unnecessary variables
mm/damon/vaddr-test: split a test function having >1024 bytes frame size
mm/damon/vaddr: remove an unnecessary warning message
mm/damon/core: remove unnecessary error messages
mm/damon/dbgfs: remove an unnecessary error message
mm/damon/core: use better timer mechanisms selection threshold
mm/damon/core: fix fake load reports due to uninterruptible sleeps
timers: implement usleep_idle_range()
filemap: remove PageHWPoison check from next_uptodate_page()
mailmap: update email address for Guo Ren
MAINTAINERS: update kdump maintainers
...
Patch series "mm/damon: Fix fake /proc/loadavg reports", v3.
This patchset fixes DAMON's fake load report issue. The first patch
makes yet another variant of usleep_range() for this fix, and the second
patch fixes the issue of DAMON by making it using the newly introduced
function.
This patch (of 2):
Some kernel threads such as DAMON could need to repeatedly sleep in
micro seconds level. Because usleep_range() sleeps in uninterruptible
state, however, such threads would make /proc/loadavg reports fake load.
To help such cases, this commit implements a variant of usleep_range()
called usleep_idle_range(). It is same to usleep_range() but sets the
state of the current task as TASK_IDLE while sleeping.
Link: https://lkml.kernel.org/r/20211126145015.15862-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20211126145015.15862-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Cc: John Stultz <john.stultz@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull tracing fixes from Steven Rostedt:
"Tracing, ftrace and tracefs fixes:
- Have tracefs honor the gid mount option
- Have new files in tracefs inherit the parent ownership
- Have direct_ops unregister when it has no more functions
- Properly clean up the ops when unregistering multi direct ops
- Add a sample module to test the multiple direct ops
- Fix memory leak in error path of __create_synth_event()"
* tag 'trace-v5.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix possible memory leak in __create_synth_event() error path
ftrace/samples: Add module to test multi direct modify interface
ftrace: Add cleanup to unregister_ftrace_direct_multi
ftrace: Use direct_ops hash in unregister_ftrace_direct
tracefs: Set all files to the same group ownership as the mount option
tracefs: Have new files inherit the ownership of their parent
Pull aio poll fixes from Eric Biggers:
"Fix three bugs in aio poll, and one issue with POLLFREE more broadly:
- aio poll didn't handle POLLFREE, causing a use-after-free.
- aio poll could block while the file is ready.
- aio poll called eventfd_signal() when it isn't allowed.
- POLLFREE didn't handle multiple exclusive waiters correctly.
This has been tested with the libaio test suite, as well as with test
programs I wrote that reproduce the first two bugs. I am sending this
pull request myself as no one seems to be maintaining this code"
* tag 'aio-poll-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux:
aio: Fix incorrect usage of eventfd_signal_allowed()
aio: fix use-after-free due to missing POLLFREE handling
aio: keep poll requests on waitqueue until completed
signalfd: use wake_up_pollfree()
binder: use wake_up_pollfree()
wait: add wake_up_pollfree()
Commit 354e8f1970 ("bpf: Support <8-byte scalar spill and refill")
introduced support in the verifier to track <8B spill/fills of scalars.
The backtracking logic for the precision bit was however skipping
spill/fills of less than 8B. That could cause state pruning to consider
two states equivalent when they shouldn't be.
As an example, consider the following bytecode snippet:
0: r7 = r1
1: call bpf_get_prandom_u32
2: r6 = 2
3: if r0 == 0 goto pc+1
4: r6 = 3
...
8: [state pruning point]
...
/* u32 spill/fill */
10: *(u32 *)(r10 - 8) = r6
11: r8 = *(u32 *)(r10 - 8)
12: r0 = 0
13: if r8 == 3 goto pc+1
14: r0 = 1
15: exit
The verifier first walks the path with R6=3. Given the support for <8B
spill/fills, at instruction 13, it knows the condition is true and skips
instruction 14. At that point, the backtracking logic kicks in but stops
at the fill instruction since it only propagates the precision bit for
8B spill/fill. When the verifier then walks the path with R6=2, it will
consider it safe at instruction 8 because R6 is not marked as needing
precision. Instruction 14 is thus never walked and is then incorrectly
removed as 'dead code'.
It's also possible to lead the verifier to accept e.g. an out-of-bound
memory access instead of causing an incorrect dead code elimination.
This regression was found via Cilium's bpf-next CI where it was causing
a conntrack map update to be silently skipped because the code had been
removed by the verifier.
This commit fixes it by enabling support for <8B spill/fills in the
bactracking logic. In case of a <8B spill/fill, the full 8B stack slot
will be marked as needing precision. Then, in __mark_chain_precision,
any tracked register spilled in a marked slot will itself be marked as
needing precision, regardless of the spill size. This logic makes two
assumptions: (1) only 8B-aligned spill/fill are tracked and (2) spilled
registers are only tracked if the spill and fill sizes are equal. Commit
ef979017b8 ("bpf: selftest: Add verifier tests for <8-byte scalar
spill and refill") covers the first assumption and the next commit in
this patchset covers the second.
Fixes: 354e8f1970 ("bpf: Support <8-byte scalar spill and refill")
Signed-off-by: Paul Chaignon <paul@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The semantics of the rlimit max values differs from ucounts itself. When
creating a new userns, we store the current rlimit of the process in
ucount_max. Thus, the value of the limit in the parent userns is saved
in the created one.
The problem is that now we are taking the maximum value for counter from
the same userns. So for init_user_ns it will always be RLIM_INFINITY.
To fix the problem we need to check the counter value with the max value
stored in userns.
Reproducer:
su - test -c "ulimit -u 3; sleep 5 & sleep 6 & unshare -U --map-root-user sh -c 'sleep 7 & sleep 8 & date; wait'"
Before:
[1] 175
[2] 176
Fri Nov 26 13:48:20 UTC 2021
[1]- Done sleep 5
[2]+ Done sleep 6
After:
[1] 167
[2] 168
sh: fork: retry: Resource temporarily unavailable
sh: fork: retry: Resource temporarily unavailable
sh: fork: retry: Resource temporarily unavailable
sh: fork: retry: Resource temporarily unavailable
sh: fork: retry: Resource temporarily unavailable
sh: fork: retry: Resource temporarily unavailable
sh: fork: retry: Resource temporarily unavailable
sh: fork: Interrupted system call
[1]- Done sleep 5
[2]+ Done sleep 6
Fixes: c54b245d01 ("Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace")
Reported-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Alexey Gladkov <legion@kernel.org>
Link: https://lkml.kernel.org/r/024ec805f6e16896f0b23e094773790d171d2c1c.1638218242.git.legion@kernel.org
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Pull networking fixes from Jakub Kicinski:
"Including fixes from bpf, can and netfilter.
Current release - regressions:
- bpf, sockmap: re-evaluate proto ops when psock is removed from
sockmap
Current release - new code bugs:
- bpf: fix bpf_check_mod_kfunc_call for built-in modules
- ice: fixes for TC classifier offloads
- vrf: don't run conntrack on vrf with !dflt qdisc
Previous releases - regressions:
- bpf: fix the off-by-two error in range markings
- seg6: fix the iif in the IPv6 socket control block
- devlink: fix netns refcount leak in devlink_nl_cmd_reload()
- dsa: mv88e6xxx: fix "don't use PHY_DETECT on internal PHY's"
- dsa: mv88e6xxx: allow use of PHYs on CPU and DSA ports
Previous releases - always broken:
- ethtool: do not perform operations on net devices being
unregistered
- udp: use datalen to cap max gso segments
- ice: fix races in stats collection
- fec: only clear interrupt of handling queue in fec_enet_rx_queue()
- m_can: pci: fix incorrect reference clock rate
- m_can: disable and ignore ELO interrupt
- mvpp2: fix XDP rx queues registering
Misc:
- treewide: add missing includes masked by cgroup -> bpf.h
dependency"
* tag 'net-5.16-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (82 commits)
net: dsa: mv88e6xxx: allow use of PHYs on CPU and DSA ports
net: wwan: iosm: fixes unable to send AT command during mbim tx
net: wwan: iosm: fixes net interface nonfunctional after fw flash
net: wwan: iosm: fixes unnecessary doorbell send
net: dsa: felix: Fix memory leak in felix_setup_mmio_filtering
MAINTAINERS: s390/net: remove myself as maintainer
net/sched: fq_pie: prevent dismantle issue
net: mana: Fix memory leak in mana_hwc_create_wq
seg6: fix the iif in the IPv6 socket control block
nfp: Fix memory leak in nfp_cpp_area_cache_add()
nfc: fix potential NULL pointer deref in nfc_genl_dump_ses_done
nfc: fix segfault in nfc_genl_dump_devices_done
udp: using datalen to cap max gso segments
net: dsa: mv88e6xxx: error handling for serdes_power functions
can: kvaser_usb: get CAN clock frequency from device
can: kvaser_pciefd: kvaser_pciefd_rx_error_frame(): increase correct stats->{rx,tx}_errors counter
net: mvpp2: fix XDP rx queues registering
vmxnet3: fix minimum vectors alloc issue
net, neigh: clear whole pneigh_entry at alloc time
net: dsa: mv88e6xxx: fix "don't use PHY_DETECT on internal PHY's"
...
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>
