Do not use rlimit-based memory accounting for bpf_struct_ops maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201201215900.3569844-20-guro@fb.com
Do not use rlimit-based memory accounting for arraymap maps.
It has been replaced with the memcg-based memory accounting.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201201215900.3569844-19-guro@fb.com
Account memory used by cgroup storage maps including metadata
structures.
Account the percpu memory for the percpu flavor of cgroup storage.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201201215900.3569844-11-guro@fb.com
This patch enables memcg-based memory accounting for memory allocated
by __bpf_map_area_alloc(), which is used by many types of bpf maps for
large initial memory allocations.
Please note, that __bpf_map_area_alloc() should not be used outside of
map creation paths without setting the active memory cgroup to the
map's memory cgroup.
Following patches in the series will refine the accounting for
some of the map types.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201201215900.3569844-8-guro@fb.com
Bpf maps can be updated from an interrupt context and in such
case there is no process which can be charged. It makes the memory
accounting of bpf maps non-trivial.
Fortunately, after commit 4127c6504f ("mm: kmem: enable kernel
memcg accounting from interrupt contexts") and commit b87d8cefe4
("mm, memcg: rework remote charging API to support nesting")
it's finally possible.
To make the ownership model simple and consistent, when the map
is created, the memory cgroup of the current process is recorded.
All subsequent allocations related to the bpf map are charged to
the same memory cgroup. It includes allocations made by any processes
(even if they do belong to a different cgroup) and from interrupts.
This commit introduces 3 new helpers, which will be used by following
commits to enable the accounting of bpf maps memory:
- bpf_map_kmalloc_node()
- bpf_map_kzalloc()
- bpf_map_alloc_percpu()
They are wrapping popular memory allocation functions. They set
the active memory cgroup to the map's memory cgroup and add
__GFP_ACCOUNT to the passed gfp flags. Then they call into
the corresponding memory allocation function and restore
the original active memory cgroup.
These helpers are supposed to use everywhere except the map creation
path. During the map creation when the map structure is allocated by
itself, it cannot be passed to those helpers. In those cases default
memory allocation function will be used with the __GFP_ACCOUNT flag.
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201201215900.3569844-7-guro@fb.com
Include memory used by bpf programs into the memcg-based accounting.
This includes the memory used by programs itself, auxiliary data,
statistics and bpf line info. A memory cgroup containing the
process which loads the program is getting charged.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201201215900.3569844-6-guro@fb.com
Patch series "mm: allow mapping accounted kernel pages to userspace", v6.
Currently a non-slab kernel page which has been charged to a memory cgroup
can't be mapped to userspace. The underlying reason is simple: PageKmemcg
flag is defined as a page type (like buddy, offline, etc), so it takes a
bit from a page->mapped counter. Pages with a type set can't be mapped to
userspace.
But in general the kmemcg flag has nothing to do with mapping to
userspace. It only means that the page has been accounted by the page
allocator, so it has to be properly uncharged on release.
Some bpf maps are mapping the vmalloc-based memory to userspace, and their
memory can't be accounted because of this implementation detail.
This patchset removes this limitation by moving the PageKmemcg flag into
one of the free bits of the page->mem_cgroup pointer. Also it formalizes
accesses to the page->mem_cgroup and page->obj_cgroups using new helpers,
adds several checks and removes a couple of obsolete functions. As the
result the code became more robust with fewer open-coded bit tricks.
This patch (of 4):
Currently there are many open-coded reads of the page->mem_cgroup pointer,
as well as a couple of read helpers, which are barely used.
It creates an obstacle on a way to reuse some bits of the pointer for
storing additional bits of information. In fact, we already do this for
slab pages, where the last bit indicates that a pointer has an attached
vector of objcg pointers instead of a regular memcg pointer.
This commits uses 2 existing helpers and introduces a new helper to
converts all read sides to calls of these helpers:
struct mem_cgroup *page_memcg(struct page *page);
struct mem_cgroup *page_memcg_rcu(struct page *page);
struct mem_cgroup *page_memcg_check(struct page *page);
page_memcg_check() is intended to be used in cases when the page can be a
slab page and have a memcg pointer pointing at objcg vector. It does
check the lowest bit, and if set, returns NULL. page_memcg() contains a
VM_BUG_ON_PAGE() check for the page not being a slab page.
To make sure nobody uses a direct access, struct page's
mem_cgroup/obj_cgroups is converted to unsigned long memcg_data.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Link: https://lkml.kernel.org/r/20201027001657.3398190-1-guro@fb.com
Link: https://lkml.kernel.org/r/20201027001657.3398190-2-guro@fb.com
Link: https://lore.kernel.org/bpf/20201201215900.3569844-2-guro@fb.com
Provide a wrapper function to get the IMA hash of an inode. This helper
is useful in fingerprinting files (e.g executables on execution) and
using these fingerprints in detections like an executable unlinking
itself.
Since the ima_inode_hash can sleep, it's only allowed for sleepable
LSM hooks.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20201124151210.1081188-3-kpsingh@chromium.org
The current implementation uses a number of gotos to implement a loop
and different paths within the loop, which makes the code less readable
than it would be with an explicit while-loop. This patch also replaces a
chain of if/if-elses keyed on the same expression with a switch
statement.
No change in behaviour is intended.
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201121015509.3594191-1-wedsonaf@google.com
Given .BTF section is not allocatable, it will get trimmed after module is
loaded. BPF system handles that properly by creating an independent copy of
data. But prevent any accidental misused by resetting the pointer to BTF data.
Fixes: 36e68442d1 ("bpf: Load and verify kernel module BTFs")
Suggested-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jessica Yu <jeyu@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/bpf/20201121070829.2612884-2-andrii@kernel.org
Simplify task_file_seq_get_next() by removing two in/out arguments: task
and fstruct. Use info->task and info->files instead.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20201120002833.2481110-1-songliubraving@fb.com
The helper uses CLOCK_MONOTONIC_COARSE source of time that is less
accurate but more performant.
We have a BPF CGROUP_SKB firewall that supports event logging through
bpf_perf_event_output(). Each event has a timestamp and currently we use
bpf_ktime_get_ns() for it. Use of bpf_ktime_get_coarse_ns() saves ~15-20
ns in time required for event logging.
bpf_ktime_get_ns():
EgressLogByRemoteEndpoint 113.82ns 8.79M
bpf_ktime_get_coarse_ns():
EgressLogByRemoteEndpoint 95.40ns 10.48M
Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201117184549.257280-1-me@ubique.spb.ru
The helper allows modification of certain bits on the linux_binprm
struct starting with the secureexec bit which can be updated using the
BPF_F_BPRM_SECUREEXEC flag.
secureexec can be set by the LSM for privilege gaining executions to set
the AT_SECURE auxv for glibc. When set, the dynamic linker disables the
use of certain environment variables (like LD_PRELOAD).
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201117232929.2156341-1-kpsingh@chromium.org
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-11-14
1) Add BTF generation for kernel modules and extend BTF infra in kernel
e.g. support for split BTF loading and validation, from Andrii Nakryiko.
2) Support for pointers beyond pkt_end to recognize LLVM generated patterns
on inlined branch conditions, from Alexei Starovoitov.
3) Implements bpf_local_storage for task_struct for BPF LSM, from KP Singh.
4) Enable FENTRY/FEXIT/RAW_TP tracing program to use the bpf_sk_storage
infra, from Martin KaFai Lau.
5) Add XDP bulk APIs that introduce a defer/flush mechanism to optimize the
XDP_REDIRECT path, from Lorenzo Bianconi.
6) Fix a potential (although rather theoretical) deadlock of hashtab in NMI
context, from Song Liu.
7) Fixes for cross and out-of-tree build of bpftool and runqslower allowing build
for different target archs on same source tree, from Jean-Philippe Brucker.
8) Fix error path in htab_map_alloc() triggered from syzbot, from Eric Dumazet.
9) Move functionality from test_tcpbpf_user into the test_progs framework so it
can run in BPF CI, from Alexander Duyck.
10) Lift hashtab key_size limit to be larger than MAX_BPF_STACK, from Florian Lehner.
Note that for the fix from Song we have seen a sparse report on context
imbalance which requires changes in sparse itself for proper annotation
detection where this is currently being discussed on linux-sparse among
developers [0]. Once we have more clarification/guidance after their fix,
Song will follow-up.
[0] https://lore.kernel.org/linux-sparse/CAHk-=wh4bx8A8dHnX612MsDO13st6uzAz1mJ1PaHHVevJx_ZCw@mail.gmail.com/T/https://lore.kernel.org/linux-sparse/20201109221345.uklbp3lzgq6g42zb@ltop.local/T/
* git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (66 commits)
net: mlx5: Add xdp tx return bulking support
net: mvpp2: Add xdp tx return bulking support
net: mvneta: Add xdp tx return bulking support
net: page_pool: Add bulk support for ptr_ring
net: xdp: Introduce bulking for xdp tx return path
bpf: Expose bpf_d_path helper to sleepable LSM hooks
bpf: Augment the set of sleepable LSM hooks
bpf: selftest: Use bpf_sk_storage in FENTRY/FEXIT/RAW_TP
bpf: Allow using bpf_sk_storage in FENTRY/FEXIT/RAW_TP
bpf: Rename some functions in bpf_sk_storage
bpf: Folding omem_charge() into sk_storage_charge()
selftests/bpf: Add asm tests for pkt vs pkt_end comparison.
selftests/bpf: Add skb_pkt_end test
bpf: Support for pointers beyond pkt_end.
tools/bpf: Always run the *-clean recipes
tools/bpf: Add bootstrap/ to .gitignore
bpf: Fix NULL dereference in bpf_task_storage
tools/bpftool: Fix build slowdown
tools/runqslower: Build bpftool using HOSTCC
tools/runqslower: Enable out-of-tree build
...
====================
Link: https://lore.kernel.org/r/20201114020819.29584-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Sleepable hooks are never called from an NMI/interrupt context, so it
is safe to use the bpf_d_path helper in LSM programs attaching to these
hooks.
The helper is not restricted to sleepable programs and merely uses the
list of sleepable hooks as the initial subset of LSM hooks where it can
be used.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20201113005930.541956-3-kpsingh@chromium.org
Update the set of sleepable hooks with the ones that do not trigger
a warning with might_fault() when exercised with the correct kernel
config options enabled, i.e.
DEBUG_ATOMIC_SLEEP=y
LOCKDEP=y
PROVE_LOCKING=y
This means that a sleepable LSM eBPF program can be attached to these
LSM hooks. A new helper method bpf_lsm_is_sleepable_hook is added and
the set is maintained locally in bpf_lsm.c
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20201113005930.541956-2-kpsingh@chromium.org
This patch enables the FENTRY/FEXIT/RAW_TP tracing program to use
the bpf_sk_storage_(get|delete) helper, so those tracing programs
can access the sk's bpf_local_storage and the later selftest
will show some examples.
The bpf_sk_storage is currently used in bpf-tcp-cc, tc,
cg sockops...etc which is running either in softirq or
task context.
This patch adds bpf_sk_storage_get_tracing_proto and
bpf_sk_storage_delete_tracing_proto. They will check
in runtime that the helpers can only be called when serving
softirq or running in a task context. That should enable
most common tracing use cases on sk.
During the load time, the new tracing_allowed() function
will ensure the tracing prog using the bpf_sk_storage_(get|delete)
helper is not tracing any bpf_sk_storage*() function itself.
The sk is passed as "void *" when calling into bpf_local_storage.
This patch only allows tracing a kernel function.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201112211313.2587383-1-kafai@fb.com
This patch adds the verifier support to recognize inlined branch conditions.
The LLVM knows that the branch evaluates to the same value, but the verifier
couldn't track it. Hence causing valid programs to be rejected.
The potential LLVM workaround: https://reviews.llvm.org/D87428
can have undesired side effects, since LLVM doesn't know that
skb->data/data_end are being compared. LLVM has to introduce extra boolean
variable and use inline_asm trick to force easier for the verifier assembly.
Instead teach the verifier to recognize that
r1 = skb->data;
r1 += 10;
r2 = skb->data_end;
if (r1 > r2) {
here r1 points beyond packet_end and
subsequent
if (r1 > r2) // always evaluates to "true".
}
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20201111031213.25109-2-alexei.starovoitov@gmail.com
Current release - regressions:
- arm64: dts: fsl-ls1028a-kontron-sl28: specify in-band mode for ENETC
Current release - bugs in new features:
- mptcp: provide rmem[0] limit offset to fix oops
Previous release - regressions:
- IPv6: Set SIT tunnel hard_header_len to zero to fix path MTU
calculations
- lan743x: correctly handle chips with internal PHY
- bpf: Don't rely on GCC __attribute__((optimize)) to disable GCSE
- mlx5e: Fix VXLAN port table synchronization after function reload
Previous release - always broken:
- bpf: Zero-fill re-used per-cpu map element
- net: udp: fix out-of-order packets when forwarding with UDP GSO
fraglists turned on
- fix UDP header access on Fast/frag0 UDP GRO
- fix IP header access and skb lookup on Fast/frag0 UDP GRO
- ethtool: netlink: add missing netdev_features_change() call
- net: Update window_clamp if SOCK_RCVBUF is set
- igc: Fix returning wrong statistics
- ch_ktls: fix multiple leaks and corner cases in Chelsio TLS offload
- tunnels: Fix off-by-one in lower MTU bounds for ICMP/ICMPv6 replies
- r8169: disable hw csum for short packets on all chip versions
- vrf: Fix fast path output packet handling with async Netfilter rules
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Current release - regressions:
- arm64: dts: fsl-ls1028a-kontron-sl28: specify in-band mode for
ENETC
Current release - bugs in new features:
- mptcp: provide rmem[0] limit offset to fix oops
Previous release - regressions:
- IPv6: Set SIT tunnel hard_header_len to zero to fix path MTU
calculations
- lan743x: correctly handle chips with internal PHY
- bpf: Don't rely on GCC __attribute__((optimize)) to disable GCSE
- mlx5e: Fix VXLAN port table synchronization after function reload
Previous release - always broken:
- bpf: Zero-fill re-used per-cpu map element
- fix out-of-order UDP packets when forwarding with UDP GSO fraglists
turned on:
- fix UDP header access on Fast/frag0 UDP GRO
- fix IP header access and skb lookup on Fast/frag0 UDP GRO
- ethtool: netlink: add missing netdev_features_change() call
- net: Update window_clamp if SOCK_RCVBUF is set
- igc: Fix returning wrong statistics
- ch_ktls: fix multiple leaks and corner cases in Chelsio TLS offload
- tunnels: Fix off-by-one in lower MTU bounds for ICMP/ICMPv6 replies
- r8169: disable hw csum for short packets on all chip versions
- vrf: Fix fast path output packet handling with async Netfilter
rules"
* tag 'net-5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (65 commits)
lan743x: fix use of uninitialized variable
net: udp: fix IP header access and skb lookup on Fast/frag0 UDP GRO
net: udp: fix UDP header access on Fast/frag0 UDP GRO
devlink: Avoid overwriting port attributes of registered port
vrf: Fix fast path output packet handling with async Netfilter rules
cosa: Add missing kfree in error path of cosa_write
net: switch to the kernel.org patchwork instance
ch_ktls: stop the txq if reaches threshold
ch_ktls: tcb update fails sometimes
ch_ktls/cxgb4: handle partial tag alone SKBs
ch_ktls: don't free skb before sending FIN
ch_ktls: packet handling prior to start marker
ch_ktls: Correction in middle record handling
ch_ktls: missing handling of header alone
ch_ktls: Correction in trimmed_len calculation
cxgb4/ch_ktls: creating skbs causes panic
ch_ktls: Update cheksum information
ch_ktls: Correction in finding correct length
cxgb4/ch_ktls: decrypted bit is not enough
net/x25: Fix null-ptr-deref in x25_connect
...
Make the intel_pstate driver behave as expected when it operates in
the passive mode with HWP enabled and the "powersave" governor on
top of it.
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Merge tag 'pm-5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"Make the intel_pstate driver behave as expected when it operates in
the passive mode with HWP enabled and the 'powersave' governor on top
of it"
* tag 'pm-5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: intel_pstate: Take CPUFREQ_GOV_STRICT_TARGET into account
cpufreq: Add strict_target to struct cpufreq_policy
cpufreq: Introduce CPUFREQ_GOV_STRICT_TARGET
cpufreq: Introduce governor flags
In bpf_pid_task_storage_update_elem(), it missed to
test the !task_storage_ptr(task) which then could trigger a NULL
pointer exception in bpf_local_storage_update().
Fixes: 4cf1bc1f10 ("bpf: Implement task local storage")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Roman Gushchin <guro@fb.com>
Acked-by: KP Singh <kpsingh@google.com>
Link: https://lore.kernel.org/bpf/20201112001919.2028357-1-kafai@fb.com
Pull swiotlb fixes from Konrad Rzeszutek Wilk:
"Two tiny fixes for issues that make drivers under Xen unhappy under
certain conditions"
* 'stable/for-linus-5.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
swiotlb: remove the tbl_dma_addr argument to swiotlb_tbl_map_single
swiotlb: fix "x86: Don't panic if can not alloc buffer for swiotlb"
Make sure btf_parse_module() is compiled out if module BTFs are not enabled.
Fixes: 36e68442d1 ("bpf: Load and verify kernel module BTFs")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201111040645.903494-1-andrii@kernel.org
Add kernel module listener that will load/validate and unload module BTF.
Module BTFs gets ID generated for them, which makes it possible to iterate
them with existing BTF iteration API. They are given their respective module's
names, which will get reported through GET_OBJ_INFO API. They are also marked
as in-kernel BTFs for tooling to distinguish them from user-provided BTFs.
Also, similarly to vmlinux BTF, kernel module BTFs are exposed through
sysfs as /sys/kernel/btf/<module-name>. This is convenient for user-space
tools to inspect module BTF contents and dump their types with existing tools:
[vmuser@archvm bpf]$ ls -la /sys/kernel/btf
total 0
drwxr-xr-x 2 root root 0 Nov 4 19:46 .
drwxr-xr-x 13 root root 0 Nov 4 19:46 ..
...
-r--r--r-- 1 root root 888 Nov 4 19:46 irqbypass
-r--r--r-- 1 root root 100225 Nov 4 19:46 kvm
-r--r--r-- 1 root root 35401 Nov 4 19:46 kvm_intel
-r--r--r-- 1 root root 120 Nov 4 19:46 pcspkr
-r--r--r-- 1 root root 399 Nov 4 19:46 serio_raw
-r--r--r-- 1 root root 4094095 Nov 4 19:46 vmlinux
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/bpf/20201110011932.3201430-5-andrii@kernel.org
Allocate ID for vmlinux BTF. This makes it visible when iterating over all BTF
objects in the system. To allow distinguishing vmlinux BTF (and later kernel
module BTF) from user-provided BTFs, expose extra kernel_btf flag, as well as
BTF name ("vmlinux" for vmlinux BTF, will equal to module's name for module
BTF). We might want to later allow specifying BTF name for user-provided BTFs
as well, if that makes sense. But currently this is reserved only for
in-kernel BTFs.
Having in-kernel BTFs exposed IDs will allow to extend BPF APIs that require
in-kernel BTF type with ability to specify BTF types from kernel modules, not
just vmlinux BTF. This will be implemented in a follow up patch set for
fentry/fexit/fmod_ret/lsm/etc.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201110011932.3201430-3-andrii@kernel.org
Adjust in-kernel BTF implementation to support a split BTF mode of operation.
Changes are mostly mirroring libbpf split BTF changes, with the exception of
start_id being 0 for in-kernel implementation due to simpler read-only mode.
Otherwise, for split BTF logic, most of the logic of jumping to base BTF,
where necessary, is encapsulated in few helper functions. Type numbering and
string offset in a split BTF are logically continuing where base BTF ends, so
most of the high-level logic is kept without changes.
Type verification and size resolution is only doing an added resolution of new
split BTF types and relies on already cached size and type resolution results
in the base BTF.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201110011932.3201430-2-andrii@kernel.org
Pull core dump fix from Al Viro:
"Fix for multithreaded coredump playing fast and loose with getting
registers of secondary threads; if a secondary gets caught in the
middle of exit(2), the conditition it will be stopped in for dumper to
examine might be unusual enough for things to go wrong.
Quite a few architectures are fine with that, but some are not."
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
don't dump the threads that had been already exiting when zapped.
A new cpufreq governor flag will be added subsequently, so replace
the bool dynamic_switching fleid in struct cpufreq_governor with a
flags field and introduce CPUFREQ_GOV_DYNAMIC_SWITCHING to set for
the "dynamic switching" governors instead of it.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
current->group_leader->exit_signal may change during copy_process() if
current->real_parent exits.
Move the assignment inside tasklist_lock to avoid the race.
Signed-off-by: Eddy Wu <eddy_wu@trendmicro.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
parser.
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Merge tag 'perf-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fix from Thomas Gleixner:
"A single fix for the perf core plugging a memory leak in the address
filter parser"
* tag 'perf-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix a memory leak in perf_event_parse_addr_filter()
underlying RT mutex was not handled correctly and triggering a BUG()
instead of treating it as another variant of retry condition.
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Merge tag 'locking-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull futex fix from Thomas Gleixner:
"A single fix for the futex code where an intermediate state in the
underlying RT mutex was not handled correctly and triggering a BUG()
instead of treating it as another variant of retry condition"
* tag 'locking-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Handle transient "ownerless" rtmutex state correctly
- Fix the fallout of the IPI as interrupt conversion in Kconfig and the
BCM2836 interrupt chip driver/
- Fixes for interrupt affinity setting and the handling of hierarchical
irq domains in the SiFive PLIC driver.
- Make the unmapped event handling in the TI SCI driver work correctly.
- A few minor fixes and cleanups in various chip drivers and Kconfig.
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Merge tag 'irq-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
"A set of fixes for interrupt chip drivers:
- Fix the fallout of the IPI as interrupt conversion in Kconfig and
the BCM2836 interrupt chip driver
- Fixes for interrupt affinity setting and the handling of
hierarchical irq domains in the SiFive PLIC driver
- Make the unmapped event handling in the TI SCI driver work
correctly
- A few minor fixes and cleanups in various chip drivers and Kconfig"
* tag 'irq-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
dt-bindings: irqchip: ti, sci-inta: Fix diagram indentation for unmapped events
irqchip/ti-sci-inta: Add support for unmapped event handling
dt-bindings: irqchip: ti, sci-inta: Update for unmapped event handling
irqchip/renesas-intc-irqpin: Merge irlm_bit and needs_irlm
irqchip/sifive-plic: Fix chip_data access within a hierarchy
irqchip/sifive-plic: Fix broken irq_set_affinity() callback
irqchip/stm32-exti: Add all LP timer exti direct events support
irqchip/bcm2836: Fix missing __init annotation
irqchip/mips: Drop selection of IRQ_DOMAIN_HIERARCHY
irqchip/mst: Make mst_intc_of_init static
irqchip/mst: MST_IRQ should depend on ARCH_MEDIATEK or ARCH_MSTARV7
genirq: Let GENERIC_IRQ_IPI select IRQ_DOMAIN_HIERARCHY
that the lockdep interrupt state needs not to be established before calling
the RCU check.
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Merge tag 'core-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull entry code fix from Thomas Gleixner:
"A single fix for the generic entry code to correct the wrong
assumption that the lockdep interrupt state needs not to be
established before calling the RCU check"
* tag 'core-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
entry: Fix the incorrect ordering of lockdep and RCU check
Gratian managed to trigger the BUG_ON(!newowner) in fixup_pi_state_owner().
This is one possible chain of events leading to this:
Task Prio Operation
T1 120 lock(F)
T2 120 lock(F) -> blocks (top waiter)
T3 50 (RT) lock(F) -> boosts T1 and blocks (new top waiter)
XX timeout/ -> wakes T2
signal
T1 50 unlock(F) -> wakes T3 (rtmutex->owner == NULL, waiter bit is set)
T2 120 cleanup -> try_to_take_mutex() fails because T3 is the top waiter
and the lower priority T2 cannot steal the lock.
-> fixup_pi_state_owner() sees newowner == NULL -> BUG_ON()
The comment states that this is invalid and rt_mutex_real_owner() must
return a non NULL owner when the trylock failed, but in case of a queued
and woken up waiter rt_mutex_real_owner() == NULL is a valid transient
state. The higher priority waiter has simply not yet managed to take over
the rtmutex.
The BUG_ON() is therefore wrong and this is just another retry condition in
fixup_pi_state_owner().
Drop the locks, so that T3 can make progress, and then try the fixup again.
Gratian provided a great analysis, traces and a reproducer. The analysis is
to the point, but it confused the hell out of that tglx dude who had to
page in all the futex horrors again. Condensed version is above.
[ tglx: Wrote comment and changelog ]
Fixes: c1e2f0eaf0 ("futex: Avoid violating the 10th rule of futex")
Reported-by: Gratian Crisan <gratian.crisan@ni.com>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87a6w6x7bb.fsf@ni.com
Link: https://lore.kernel.org/r/87sg9pkvf7.fsf@nanos.tec.linutronix.de
As shown through runtime testing, the "filename" allocation is not
always freed in perf_event_parse_addr_filter().
There are three possible ways that this could happen:
- It could be allocated twice on subsequent iterations through the loop,
- or leaked on the success path,
- or on the failure path.
Clean up the code flow to make it obvious that 'filename' is always
freed in the reallocation path and in the two return paths as well.
We rely on the fact that kfree(NULL) is NOP and filename is initialized
with NULL.
This fixes the leak. No other side effects expected.
[ Dan Carpenter: cleaned up the code flow & added a changelog. ]
[ Ingo Molnar: updated the changelog some more. ]
Fixes: 375637bc52 ("perf/core: Introduce address range filtering")
Signed-off-by: "kiyin(尹亮)" <kiyin@tencent.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: "Srivatsa S. Bhat" <srivatsa@csail.mit.edu>
Cc: Anthony Liguori <aliguori@amazon.com>
--
kernel/events/core.c | 12 +++++-------
1 file changed, 5 insertions(+), 7 deletions(-)
Alexei Starovoitov says:
====================
pull-request: bpf 2020-11-06
1) Pre-allocated per-cpu hashmap needs to zero-fill reused element, from David.
2) Tighten bpf_lsm function check, from KP.
3) Fix bpftool attaching to flow dissector, from Lorenz.
4) Use -fno-gcse for the whole kernel/bpf/core.c instead of function attribute, from Ard.
* git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf: Update verification logic for LSM programs
bpf: Zero-fill re-used per-cpu map element
bpf: BPF_PRELOAD depends on BPF_SYSCALL
tools/bpftool: Fix attaching flow dissector
libbpf: Fix possible use after free in xsk_socket__delete
libbpf: Fix null dereference in xsk_socket__delete
libbpf, hashmap: Fix undefined behavior in hash_bits
bpf: Don't rely on GCC __attribute__((optimize)) to disable GCSE
tools, bpftool: Remove two unused variables.
tools, bpftool: Avoid array index warnings.
xsk: Fix possible memory leak at socket close
bpf: Add struct bpf_redir_neigh forward declaration to BPF helper defs
samples/bpf: Set rlimit for memlock to infinity in all samples
bpf: Fix -Wshadow warnings
selftest/bpf: Fix profiler test using CO-RE relocation for enums
====================
Link: https://lore.kernel.org/r/20201106221759.24143-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The current logic checks if the name of the BTF type passed in
attach_btf_id starts with "bpf_lsm_", this is not sufficient as it also
allows attachment to non-LSM hooks like the very function that performs
this check, i.e. bpf_lsm_verify_prog.
In order to ensure that this verification logic allows attachment to
only LSM hooks, the LSM_HOOK definitions in lsm_hook_defs.h are used to
generate a BTF_ID set. Upon verification, the attach_btf_id of the
program being attached is checked for presence in this set.
Fixes: 9e4e01dfd3 ("bpf: lsm: Implement attach, detach and execution")
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201105230651.2621917-1-kpsingh@chromium.org
The currently available bpf_get_current_task returns an unsigned integer
which can be used along with BPF_CORE_READ to read data from
the task_struct but still cannot be used as an input argument to a
helper that accepts an ARG_PTR_TO_BTF_ID of type task_struct.
In order to implement this helper a new return type, RET_PTR_TO_BTF_ID,
is added. This is similar to RET_PTR_TO_BTF_ID_OR_NULL but does not
require checking the nullness of returned pointer.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-6-kpsingh@chromium.org
Similar to bpf_local_storage for sockets and inodes add local storage
for task_struct.
The life-cycle of storage is managed with the life-cycle of the
task_struct. i.e. the storage is destroyed along with the owning task
with a callback to the bpf_task_storage_free from the task_free LSM
hook.
The BPF LSM allocates an __rcu pointer to the bpf_local_storage in
the security blob which are now stackable and can co-exist with other
LSMs.
The userspace map operations can be done by using a pid fd as a key
passed to the lookup, update and delete operations.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-3-kpsingh@chromium.org
Usage of spin locks was not allowed for tracing programs due to
insufficient preemption checks. The verifier does not currently prevent
LSM programs from using spin locks, but the helpers are not exposed
via bpf_lsm_func_proto.
Based on the discussion in [1], non-sleepable LSM programs should be
able to use bpf_spin_{lock, unlock}.
Sleepable LSM programs can be preempted which means that allowng spin
locks will need more work (disabling preemption and the verifier
ensuring that no sleepable helpers are called when a spin lock is held).
[1]: https://lore.kernel.org/bpf/20201103153132.2717326-1-kpsingh@chromium.org/T/#md601a053229287659071600d3483523f752cd2fb
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201106103747.2780972-2-kpsingh@chromium.org
