The verifier allows programs to call global functions as long as their
argument types match, using BTF to check the function arguments. One of the
allowed argument types to such global functions is PTR_TO_CTX; however the
check for this fails on BPF_PROG_TYPE_EXT functions because the verifier
uses the wrong type to fetch the vmlinux BTF ID for the program context
type. This failure is seen when an XDP program is loaded using
libxdp (which loads it as BPF_PROG_TYPE_EXT and attaches it to a global XDP
type program).
Fix the issue by passing in the target program type instead of the
BPF_PROG_TYPE_EXT type to bpf_prog_get_ctx() when checking function
argument compatibility.
The first Fixes tag refers to the latest commit that touched the code in
question, while the second one points to the code that first introduced
the global function call verification.
v2:
- Use resolve_prog_type()
Fixes: 3363bd0cfb ("bpf: Extend kfunc with PTR_TO_CTX, PTR_TO_MEM argument support")
Fixes: 51c39bb1d5 ("bpf: Introduce function-by-function verification")
Reported-by: Simon Sundberg <simon.sundberg@kau.se>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20220606075253.28422-1-toke@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull networking fixes from Jakub Kicinski:
"Including fixes from bpf and netfilter.
Current release - new code bugs:
- af_packet: make sure to pull the MAC header, avoid skb panic in GSO
- ptp_clockmatrix: fix inverted logic in is_single_shot()
- netfilter: flowtable: fix missing FLOWI_FLAG_ANYSRC flag
- dt-bindings: net: adin: fix adi,phy-output-clock description syntax
- wifi: iwlwifi: pcie: rename CAUSE macro, avoid MIPS build warning
Previous releases - regressions:
- Revert "net: af_key: add check for pfkey_broadcast in function
pfkey_process"
- tcp: fix tcp_mtup_probe_success vs wrong snd_cwnd
- nf_tables: disallow non-stateful expression in sets earlier
- nft_limit: clone packet limits' cost value
- nf_tables: double hook unregistration in netns path
- ping6: fix ping -6 with interface name
Previous releases - always broken:
- sched: fix memory barriers to prevent skbs from getting stuck in
lockless qdiscs
- neigh: set lower cap for neigh_managed_work rearming, avoid
constantly scheduling the probe work
- bpf: fix probe read error on big endian in ___bpf_prog_run()
- amt: memory leak and error handling fixes
Misc:
- ipv6: expand & rename accept_unsolicited_na to accept_untracked_na"
* tag 'net-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (80 commits)
net/af_packet: make sure to pull mac header
net: add debug info to __skb_pull()
net: CONFIG_DEBUG_NET depends on CONFIG_NET
stmmac: intel: Add RPL-P PCI ID
net: stmmac: use dev_err_probe() for reporting mdio bus registration failure
tipc: check attribute length for bearer name
ice: fix access-beyond-end in the switch code
nfp: remove padding in nfp_nfdk_tx_desc
ax25: Fix ax25 session cleanup problems
net: usb: qmi_wwan: Add support for Cinterion MV31 with new baseline
sfc/siena: fix wrong tx channel offset with efx_separate_tx_channels
sfc/siena: fix considering that all channels have TX queues
socket: Don't use u8 type in uapi socket.h
net/sched: act_api: fix error code in tcf_ct_flow_table_fill_tuple_ipv6()
net: ping6: Fix ping -6 with interface name
macsec: fix UAF bug for real_dev
octeontx2-af: fix error code in is_valid_offset()
wifi: mac80211: fix use-after-free in chanctx code
bonding: guard ns_targets by CONFIG_IPV6
tcp: tcp_rtx_synack() can be called from process context
...
I think there is something wrong with BPF_PROBE_MEM in ___bpf_prog_run()
in big-endian machine. Let's make a test and see what will happen if we
want to load a 'u16' with BPF_PROBE_MEM.
Let's make the src value '0x0001', the value of dest register will become
0x0001000000000000, as the value will be loaded to the first 2 byte of
DST with following code:
bpf_probe_read_kernel(&DST, SIZE, (const void *)(long) (SRC + insn->off));
Obviously, the value in DST is not correct. In fact, we can compare
BPF_PROBE_MEM with LDX_MEM_H:
DST = *(SIZE *)(unsigned long) (SRC + insn->off);
If the memory load is done by LDX_MEM_H, the value in DST will be 0x1 now.
And I think this error results in the test case 'test_bpf_sk_storage_map'
failing:
test_bpf_sk_storage_map:PASS:bpf_iter_bpf_sk_storage_map__open_and_load 0 nsec
test_bpf_sk_storage_map:PASS:socket 0 nsec
test_bpf_sk_storage_map:PASS:map_update 0 nsec
test_bpf_sk_storage_map:PASS:socket 0 nsec
test_bpf_sk_storage_map:PASS:map_update 0 nsec
test_bpf_sk_storage_map:PASS:socket 0 nsec
test_bpf_sk_storage_map:PASS:map_update 0 nsec
test_bpf_sk_storage_map:PASS:attach_iter 0 nsec
test_bpf_sk_storage_map:PASS:create_iter 0 nsec
test_bpf_sk_storage_map:PASS:read 0 nsec
test_bpf_sk_storage_map:FAIL:ipv6_sk_count got 0 expected 3
$10/26 bpf_iter/bpf_sk_storage_map:FAIL
The code of the test case is simply, it will load sk->sk_family to the
register with BPF_PROBE_MEM and check if it is AF_INET6. With this patch,
now the test case 'bpf_iter' can pass:
$10 bpf_iter:OK
Fixes: 2a02759ef5 ("bpf: Add support for BTF pointers to interpreter")
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jiang Biao <benbjiang@tencent.com>
Reviewed-by: Hao Peng <flyingpeng@tencent.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/20220524021228.533216-1-imagedong@tencent.com
Pull MM updates from Andrew Morton:
"Almost all of MM here. A few things are still getting finished off,
reviewed, etc.
- Yang Shi has improved the behaviour of khugepaged collapsing of
readonly file-backed transparent hugepages.
- Johannes Weiner has arranged for zswap memory use to be tracked and
managed on a per-cgroup basis.
- Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for
runtime enablement of the recent huge page vmemmap optimization
feature.
- Baolin Wang contributes a series to fix some issues around hugetlb
pagetable invalidation.
- Zhenwei Pi has fixed some interactions between hwpoisoned pages and
virtualization.
- Tong Tiangen has enabled the use of the presently x86-only
page_table_check debugging feature on arm64 and riscv.
- David Vernet has done some fixup work on the memcg selftests.
- Peter Xu has taught userfaultfd to handle write protection faults
against shmem- and hugetlbfs-backed files.
- More DAMON development from SeongJae Park - adding online tuning of
the feature and support for monitoring of fixed virtual address
ranges. Also easier discovery of which monitoring operations are
available.
- Nadav Amit has done some optimization of TLB flushing during
mprotect().
- Neil Brown continues to labor away at improving our swap-over-NFS
support.
- David Hildenbrand has some fixes to anon page COWing versus
get_user_pages().
- Peng Liu fixed some errors in the core hugetlb code.
- Joao Martins has reduced the amount of memory consumed by
device-dax's compound devmaps.
- Some cleanups of the arch-specific pagemap code from Anshuman
Khandual.
- Muchun Song has found and fixed some errors in the TLB flushing of
transparent hugepages.
- Roman Gushchin has done more work on the memcg selftests.
... and, of course, many smaller fixes and cleanups. Notably, the
customary million cleanup serieses from Miaohe Lin"
* tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (381 commits)
mm: kfence: use PAGE_ALIGNED helper
selftests: vm: add the "settings" file with timeout variable
selftests: vm: add "test_hmm.sh" to TEST_FILES
selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests
selftests: vm: add migration to the .gitignore
selftests/vm/pkeys: fix typo in comment
ksm: fix typo in comment
selftests: vm: add process_mrelease tests
Revert "mm/vmscan: never demote for memcg reclaim"
mm/kfence: print disabling or re-enabling message
include/trace/events/percpu.h: cleanup for "percpu: improve percpu_alloc_percpu event trace"
include/trace/events/mmflags.h: cleanup for "tracing: incorrect gfp_t conversion"
mm: fix a potential infinite loop in start_isolate_page_range()
MAINTAINERS: add Muchun as co-maintainer for HugeTLB
zram: fix Kconfig dependency warning
mm/shmem: fix shmem folio swapoff hang
cgroup: fix an error handling path in alloc_pagecache_max_30M()
mm: damon: use HPAGE_PMD_SIZE
tracing: incorrect isolate_mote_t cast in mm_vmscan_lru_isolate
nodemask.h: fix compilation error with GCC12
...
Pull networking updates from Jakub Kicinski:
"Core
----
- Support TCPv6 segmentation offload with super-segments larger than
64k bytes using the IPv6 Jumbogram extension header (AKA BIG TCP).
- Generalize skb freeing deferral to per-cpu lists, instead of
per-socket lists.
- Add a netdev statistic for packets dropped due to L2 address
mismatch (rx_otherhost_dropped).
- Continue work annotating skb drop reasons.
- Accept alternative netdev names (ALT_IFNAME) in more netlink
requests.
- Add VLAN support for AF_PACKET SOCK_RAW GSO.
- Allow receiving skb mark from the socket as a cmsg.
- Enable memcg accounting for veth queues, sysctl tables and IPv6.
BPF
---
- Add libbpf support for User Statically-Defined Tracing (USDTs).
- Speed up symbol resolution for kprobes multi-link attachments.
- Support storing typed pointers to referenced and unreferenced
objects in BPF maps.
- Add support for BPF link iterator.
- Introduce access to remote CPU map elements in BPF per-cpu map.
- Allow middle-of-the-road settings for the
kernel.unprivileged_bpf_disabled sysctl.
- Implement basic types of dynamic pointers e.g. to allow for
dynamically sized ringbuf reservations without extra memory copies.
Protocols
---------
- Retire port only listening_hash table, add a second bind table
hashed by port and address. Avoid linear list walk when binding to
very popular ports (e.g. 443).
- Add bridge FDB bulk flush filtering support allowing user space to
remove all FDB entries matching a condition.
- Introduce accept_unsolicited_na sysctl for IPv6 to implement
router-side changes for RFC9131.
- Support for MPTCP path manager in user space.
- Add MPTCP support for fallback to regular TCP for connections that
have never connected additional subflows or transmitted
out-of-sequence data (partial support for RFC8684 fallback).
- Avoid races in MPTCP-level window tracking, stabilize and improve
throughput.
- Support lockless operation of GRE tunnels with seq numbers enabled.
- WiFi support for host based BSS color collision detection.
- Add support for SO_TXTIME/SCM_TXTIME on CAN sockets.
- Support transmission w/o flow control in CAN ISOTP (ISO 15765-2).
- Support zero-copy Tx with TLS 1.2 crypto offload (sendfile).
- Allow matching on the number of VLAN tags via tc-flower.
- Add tracepoint for tcp_set_ca_state().
Driver API
----------
- Improve error reporting from classifier and action offload.
- Add support for listing line cards in switches (devlink).
- Add helpers for reporting page pool statistics with ethtool -S.
- Add support for reading clock cycles when using PTP virtual clocks,
instead of having the driver convert to time before reporting. This
makes it possible to report time from different vclocks.
- Support configuring low-latency Tx descriptor push via ethtool.
- Separate Clause 22 and Clause 45 MDIO accesses more explicitly.
New hardware / drivers
----------------------
- Ethernet:
- Marvell's Octeon NIC PCI Endpoint support (octeon_ep)
- Sunplus SP7021 SoC (sp7021_emac)
- Add support for Renesas RZ/V2M (in ravb)
- Add support for MediaTek mt7986 switches (in mtk_eth_soc)
- Ethernet PHYs:
- ADIN1100 industrial PHYs (w/ 10BASE-T1L and SQI reporting)
- TI DP83TD510 PHY
- Microchip LAN8742/LAN88xx PHYs
- WiFi:
- Driver for pureLiFi X, XL, XC devices (plfxlc)
- Driver for Silicon Labs devices (wfx)
- Support for WCN6750 (in ath11k)
- Support Realtek 8852ce devices (in rtw89)
- Mobile:
- MediaTek T700 modems (Intel 5G 5000 M.2 cards)
- CAN:
- ctucanfd: add support for CTU CAN FD open-source IP core from
Czech Technical University in Prague
Drivers
-------
- Delete a number of old drivers still using virt_to_bus().
- Ethernet NICs:
- intel: support TSO on tunnels MPLS
- broadcom: support multi-buffer XDP
- nfp: support VF rate limiting
- sfc: use hardware tx timestamps for more than PTP
- mlx5: multi-port eswitch support
- hyper-v: add support for XDP_REDIRECT
- atlantic: XDP support (including multi-buffer)
- macb: improve real-time perf by deferring Tx processing to NAPI
- High-speed Ethernet switches:
- mlxsw: implement basic line card information querying
- prestera: add support for traffic policing on ingress and egress
- Embedded Ethernet switches:
- lan966x: add support for packet DMA (FDMA)
- lan966x: add support for PTP programmable pins
- ti: cpsw_new: enable bc/mc storm prevention
- Qualcomm 802.11ax WiFi (ath11k):
- Wake-on-WLAN support for QCA6390 and WCN6855
- device recovery (firmware restart) support
- support setting Specific Absorption Rate (SAR) for WCN6855
- read country code from SMBIOS for WCN6855/QCA6390
- enable keep-alive during WoWLAN suspend
- implement remain-on-channel support
- MediaTek WiFi (mt76):
- support Wireless Ethernet Dispatch offloading packet movement
between the Ethernet switch and WiFi interfaces
- non-standard VHT MCS10-11 support
- mt7921 AP mode support
- mt7921 IPv6 NS offload support
- Ethernet PHYs:
- micrel: ksz9031/ksz9131: cabletest support
- lan87xx: SQI support for T1 PHYs
- lan937x: add interrupt support for link detection"
* tag 'net-next-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1809 commits)
ptp: ocp: Add firmware header checks
ptp: ocp: fix PPS source selector debugfs reporting
ptp: ocp: add .init function for sma_op vector
ptp: ocp: vectorize the sma accessor functions
ptp: ocp: constify selectors
ptp: ocp: parameterize input/output sma selectors
ptp: ocp: revise firmware display
ptp: ocp: add Celestica timecard PCI ids
ptp: ocp: Remove #ifdefs around PCI IDs
ptp: ocp: 32-bit fixups for pci start address
Revert "net/smc: fix listen processing for SMC-Rv2"
ath6kl: Use cc-disable-warning to disable -Wdangling-pointer
selftests/bpf: Dynptr tests
bpf: Add dynptr data slices
bpf: Add bpf_dynptr_read and bpf_dynptr_write
bpf: Dynptr support for ring buffers
bpf: Add bpf_dynptr_from_mem for local dynptrs
bpf: Add verifier support for dynptrs
bpf: Suppress 'passing zero to PTR_ERR' warning
bpf: Introduce bpf_arch_text_invalidate for bpf_prog_pack
...
This patch adds a new helper function
void *bpf_dynptr_data(struct bpf_dynptr *ptr, u32 offset, u32 len);
which returns a pointer to the underlying data of a dynptr. *len*
must be a statically known value. The bpf program may access the returned
data slice as a normal buffer (eg can do direct reads and writes), since
the verifier associates the length with the returned pointer, and
enforces that no out of bounds accesses occur.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220523210712.3641569-6-joannelkoong@gmail.com
This patch adds two helper functions, bpf_dynptr_read and
bpf_dynptr_write:
long bpf_dynptr_read(void *dst, u32 len, struct bpf_dynptr *src, u32 offset);
long bpf_dynptr_write(struct bpf_dynptr *dst, u32 offset, void *src, u32 len);
The dynptr passed into these functions must be valid dynptrs that have
been initialized.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220523210712.3641569-5-joannelkoong@gmail.com
Currently, our only way of writing dynamically-sized data into a ring
buffer is through bpf_ringbuf_output but this incurs an extra memcpy
cost. bpf_ringbuf_reserve + bpf_ringbuf_commit avoids this extra
memcpy, but it can only safely support reservation sizes that are
statically known since the verifier cannot guarantee that the bpf
program won’t access memory outside the reserved space.
The bpf_dynptr abstraction allows for dynamically-sized ring buffer
reservations without the extra memcpy.
There are 3 new APIs:
long bpf_ringbuf_reserve_dynptr(void *ringbuf, u32 size, u64 flags, struct bpf_dynptr *ptr);
void bpf_ringbuf_submit_dynptr(struct bpf_dynptr *ptr, u64 flags);
void bpf_ringbuf_discard_dynptr(struct bpf_dynptr *ptr, u64 flags);
These closely follow the functionalities of the original ringbuf APIs.
For example, all ringbuffer dynptrs that have been reserved must be
either submitted or discarded before the program exits.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20220523210712.3641569-4-joannelkoong@gmail.com
This patch adds a new api bpf_dynptr_from_mem:
long bpf_dynptr_from_mem(void *data, u32 size, u64 flags, struct bpf_dynptr *ptr);
which initializes a dynptr to point to a bpf program's local memory. For now
only local memory that is of reg type PTR_TO_MAP_VALUE is supported.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220523210712.3641569-3-joannelkoong@gmail.com
This patch adds the bulk of the verifier work for supporting dynamic
pointers (dynptrs) in bpf.
A bpf_dynptr is opaque to the bpf program. It is a 16-byte structure
defined internally as:
struct bpf_dynptr_kern {
void *data;
u32 size;
u32 offset;
} __aligned(8);
The upper 8 bits of *size* is reserved (it contains extra metadata about
read-only status and dynptr type). Consequently, a dynptr only supports
memory less than 16 MB.
There are different types of dynptrs (eg malloc, ringbuf, ...). In this
patchset, the most basic one, dynptrs to a bpf program's local memory,
is added. For now only local memory that is of reg type PTR_TO_MAP_VALUE
is supported.
In the verifier, dynptr state information will be tracked in stack
slots. When the program passes in an uninitialized dynptr
(ARG_PTR_TO_DYNPTR | MEM_UNINIT), the stack slots corresponding
to the frame pointer where the dynptr resides at are marked
STACK_DYNPTR. For helper functions that take in initialized dynptrs (eg
bpf_dynptr_read + bpf_dynptr_write which are added later in this
patchset), the verifier enforces that the dynptr has been initialized
properly by checking that their corresponding stack slots have been
marked as STACK_DYNPTR.
The 6th patch in this patchset adds test cases that the verifier should
successfully reject, such as for example attempting to use a dynptr
after doing a direct write into it inside the bpf program.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20220523210712.3641569-2-joannelkoong@gmail.com
bpf_prog_pack enables sharing huge pages among multiple BPF programs.
These pages are marked as executable before the JIT engine fill it with
BPF programs. To make these pages safe, fill the hole bpf_prog_pack with
illegal instructions before making it executable.
Fixes: 57631054fa ("bpf: Introduce bpf_prog_pack allocator")
Fixes: 33c9805860 ("bpf: Introduce bpf_jit_binary_pack_[alloc|finalize|free]")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220520235758.1858153-2-song@kernel.org
With unprivileged BPF disabled, all cmds associated with the BPF syscall
are blocked to users without CAP_BPF/CAP_SYS_ADMIN. However there are
use cases where we may wish to allow interactions with BPF programs
without being able to load and attach them. So for example, a process
with required capabilities loads/attaches a BPF program, and a process
with less capabilities interacts with it; retrieving perf/ring buffer
events, modifying map-specified config etc. With all BPF syscall
commands blocked as a result of unprivileged BPF being disabled,
this mode of interaction becomes impossible for processes without
CAP_BPF.
As Alexei notes
"The bpf ACL model is the same as traditional file's ACL.
The creds and ACLs are checked at open(). Then during file's write/read
additional checks might be performed. BPF has such functionality already.
Different map_creates have capability checks while map_lookup has:
map_get_sys_perms(map, f) & FMODE_CAN_READ.
In other words it's enough to gate FD-receiving parts of bpf
with unprivileged_bpf_disabled sysctl.
The rest is handled by availability of FD and access to files in bpffs."
So key fd creation syscall commands BPF_PROG_LOAD and BPF_MAP_CREATE
are blocked with unprivileged BPF disabled and no CAP_BPF.
And as Alexei notes, map creation with unprivileged BPF disabled off
blocks creation of maps aside from array, hash and ringbuf maps.
Programs responsible for loading and attaching the BPF program
can still control access to its pinned representation by restricting
permissions on the pin path, as with normal files.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Acked-by: KP Singh <kpsingh@kernel.org>
Link: https://lore.kernel.org/r/1652970334-30510-2-git-send-email-alan.maguire@oracle.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Instead of having uninitialized versions of arguments as separate
bpf_arg_types (eg ARG_PTR_TO_UNINIT_MEM as the uninitialized version
of ARG_PTR_TO_MEM), we can instead use MEM_UNINIT as a bpf_type_flag
modifier to denote that the argument is uninitialized.
Doing so cleans up some of the logic in the verifier. We no longer
need to do two checks against an argument type (eg "if
(base_type(arg_type) == ARG_PTR_TO_MEM || base_type(arg_type) ==
ARG_PTR_TO_UNINIT_MEM)"), since uninitialized and initialized
versions of the same argument type will now share the same base type.
In the near future, MEM_UNINIT will be used by dynptr helper functions
as well.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20220509224257.3222614-2-joannelkoong@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The combination of jit blinding and pointers to bpf subprogs causes:
[ 36.989548] BUG: unable to handle page fault for address: 0000000100000001
[ 36.990342] #PF: supervisor instruction fetch in kernel mode
[ 36.990968] #PF: error_code(0x0010) - not-present page
[ 36.994859] RIP: 0010:0x100000001
[ 36.995209] Code: Unable to access opcode bytes at RIP 0xffffffd7.
[ 37.004091] Call Trace:
[ 37.004351] <TASK>
[ 37.004576] ? bpf_loop+0x4d/0x70
[ 37.004932] ? bpf_prog_3899083f75e4c5de_F+0xe3/0x13b
The jit blinding logic didn't recognize that ld_imm64 with an address
of bpf subprogram is a special instruction and proceeded to randomize it.
By itself it wouldn't have been an issue, but jit_subprogs() logic
relies on two step process to JIT all subprogs and then JIT them
again when addresses of all subprogs are known.
Blinding process in the first JIT phase caused second JIT to miss
adjustment of special ld_imm64.
Fix this issue by ignoring special ld_imm64 instructions that don't have
user controlled constants and shouldn't be blinded.
Fixes: 69c087ba62 ("bpf: Add bpf_for_each_map_elem() helper")
Reported-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220513011025.13344-1-alexei.starovoitov@gmail.com
The cnt value in the 'cnt >= BPF_MAX_TRAMP_PROGS' check does not
include BPF_TRAMP_MODIFY_RETURN bpf programs, so the number of
the attached BPF_TRAMP_MODIFY_RETURN bpf programs in a trampoline
can exceed BPF_MAX_TRAMP_PROGS.
When this happens, the assignment '*progs++ = aux->prog' in
bpf_trampoline_get_progs() will cause progs array overflow as the
progs field in the bpf_tramp_progs struct can only hold at most
BPF_MAX_TRAMP_PROGS bpf programs.
Fixes: 88fd9e5352 ("bpf: Refactor trampoline update code")
Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Link: https://lore.kernel.org/r/20220430130803.210624-1-ytcoode@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pass a cookie along with BPF_LINK_CREATE requests.
Add a bpf_cookie field to struct bpf_tracing_link to attach a cookie.
The cookie of a bpf_tracing_link is available by calling
bpf_get_attach_cookie when running the BPF program of the attached
link.
The value of a cookie will be set at bpf_tramp_run_ctx by the
trampoline of the link.
Signed-off-by: Kui-Feng Lee <kuifeng@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220510205923.3206889-4-kuifeng@fb.com
Replace struct bpf_tramp_progs with struct bpf_tramp_links to collect
struct bpf_tramp_link(s) for a trampoline. struct bpf_tramp_link
extends bpf_link to act as a linked list node.
arch_prepare_bpf_trampoline() accepts a struct bpf_tramp_links to
collects all bpf_tramp_link(s) that a trampoline should call.
Change BPF trampoline and bpf_struct_ops to pass bpf_tramp_links
instead of bpf_tramp_progs.
Signed-off-by: Kui-Feng Lee <kuifeng@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220510205923.3206889-2-kuifeng@fb.com
