In bpf_jit_build_body(), the mapping of TMP_REG_1 and TMP_REG_2's bpf
register to ppc register is evalulated at every use despite not
changing. Instead, determine the ppc register once and store the result.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[Rebased, converted additional usage sites]
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0944e2f0fa6dd254ea401f1c946fb6c9a5294278.1644834730.git.naveen.n.rao@linux.vnet.ibm.com
When calling BPF helpers, we load the function address to call into a
register. This can result in upto 5 instructions. Optimize this by
instead using the kernel toc in r2 and adjusting offset to the BPF
helper. This works since all BPF helpers are part of kernel text, and
all BPF programs/functions utilize the kernel TOC.
Further more:
- load the actual function entry address in elf v1, rather than loading
it through the function descriptor address.
- load the Local Entry Point (LEP) in elf v2 skipping TOC setup.
- consolidate code across elf abi v1 and v2 by using r12 on both.
Reported-by: Anton Blanchard <anton@ozlabs.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1233c7544e60dcb021c52b1f840b0f21a87b33ed.1644834730.git.naveen.n.rao@linux.vnet.ibm.com
BPF helpers always reside in core kernel and all BPF programs use the
kernel TOC. As such, there is no need to load the TOC before calling
helpers or other BPF functions. Drop code to do the same.
Add a check to ensure we don't proceed if this assumption ever changes
in future.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a3cd3da4d24d95d845cd10382b1af083600c9074.1644834730.git.naveen.n.rao@linux.vnet.ibm.com
In preparation for using kernel TOC, load the same in r2 on entry. With
elfv1, the kernel TOC is already setup by our caller.
We adjust the number of instructions to skip on a tail call accordingly.
We get rid of the #ifdef in bpf_jit_emit_tail_call() since
FUNCTION_DESCR_SIZE is itself under a #ifdef.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/18a05a4ceec14a8617c9dd4b7128d0afa83fd14e.1644834730.git.naveen.n.rao@linux.vnet.ibm.com
In some scenarios, it is possible that the program epilogue is outside
the branch range for a BPF_EXIT instruction. Instead of rejecting such
programs, emit epilogue as an alternate exit point from the program.
Track the location of the same so that subsequent exits can take either
of the two paths.
Reported-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/33aa2e92645a92712be23b18035a2c6dcb92ff8d.1644834730.git.naveen.n.rao@linux.vnet.ibm.com
PPC_BCC() emits two instructions to accommodate scenarios where we need
to branch outside the range of a conditional branch. PPC_BCC_SHORT()
emits a single branch instruction and can be used when the branch is
known to be within a conditional branch range.
Convert some of the uses of PPC_BCC() in the powerpc BPF JIT over to
PPC_BCC_SHORT() where we know the branch range.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/edbca01377d1d5f472868bf6d8962b0a0d85b96f.1644834730.git.naveen.n.rao@linux.vnet.ibm.com
Johan reported the below crash with test_bpf on ppc64 e5500:
test_bpf: #296 ALU_END_FROM_LE 64: 0x0123456789abcdef -> 0x67452301 jited:1
Oops: Exception in kernel mode, sig: 4 [#1]
BE PAGE_SIZE=4K SMP NR_CPUS=24 QEMU e500
Modules linked in: test_bpf(+)
CPU: 0 PID: 76 Comm: insmod Not tainted 5.14.0-03771-g98c2059e008a-dirty #1
NIP: 8000000000061c3c LR: 80000000006dea64 CTR: 8000000000061c18
REGS: c0000000032d3420 TRAP: 0700 Not tainted (5.14.0-03771-g98c2059e008a-dirty)
MSR: 0000000080089000 <EE,ME> CR: 88002822 XER: 20000000 IRQMASK: 0
<...>
NIP [8000000000061c3c] 0x8000000000061c3c
LR [80000000006dea64] .__run_one+0x104/0x17c [test_bpf]
Call Trace:
.__run_one+0x60/0x17c [test_bpf] (unreliable)
.test_bpf_init+0x6a8/0xdc8 [test_bpf]
.do_one_initcall+0x6c/0x28c
.do_init_module+0x68/0x28c
.load_module+0x2460/0x2abc
.__do_sys_init_module+0x120/0x18c
.system_call_exception+0x110/0x1b8
system_call_common+0xf0/0x210
--- interrupt: c00 at 0x101d0acc
<...>
---[ end trace 47b2bf19090bb3d0 ]---
Illegal instruction
The illegal instruction turned out to be 'ldbrx' emitted for
BPF_FROM_[L|B]E, which was only introduced in ISA v2.06. Guard use of
the same and implement an alternative approach for older processors.
Fixes: 156d0e290e ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF")
Reported-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d1e51c6fdf572062cf3009a751c3406bda01b832.1641468127.git.naveen.n.rao@linux.vnet.ibm.com
- Optimise radix KVM guest entry/exit by 2x on Power9/Power10.
- Allow firmware to tell us whether to disable the entry and uaccess flushes on Power10
or later CPUs.
- Add BPF_PROBE_MEM support for 32 and 64-bit BPF jits.
- Several fixes and improvements to our hard lockup watchdog.
- Activate HAVE_DYNAMIC_FTRACE_WITH_REGS on 32-bit.
- Allow building the 64-bit Book3S kernel without hash MMU support, ie. Radix only.
- Add KUAP (SMAP) support for 40x, 44x, 8xx, Book3E (64-bit).
- Add new encodings for perf_mem_data_src.mem_hops field, and use them on Power10.
- A series of small performance improvements to 64-bit interrupt entry.
- Several commits fixing issues when building with the clang integrated assembler.
- Many other small features and fixes.
Thanks to: Alan Modra, Alexey Kardashevskiy, Ammar Faizi, Anders Roxell, Arnd Bergmann,
Athira Rajeev, Cédric Le Goater, Christophe JAILLET, Christophe Leroy, Christoph Hellwig,
Daniel Axtens, David Yang, Erhard Furtner, Fabiano Rosas, Greg Kroah-Hartman, Guo Ren,
Hari Bathini, Jason Wang, Joel Stanley, Julia Lawall, Kajol Jain, Kees Cook, Laurent
Dufour, Madhavan Srinivasan, Mark Brown, Minghao Chi, Nageswara R Sastry, Naresh Kamboju,
Nathan Chancellor, Nathan Lynch, Nicholas Piggin, Nick Child, Oliver O'Halloran, Peiwei
Hu, Randy Dunlap, Ravi Bangoria, Rob Herring, Russell Currey, Sachin Sant, Sean
Christopherson, Segher Boessenkool, Thadeu Lima de Souza Cascardo, Tyrel Datwyler, Xiang
wangx, Yang Guang.
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Merge tag 'powerpc-5.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
- Optimise radix KVM guest entry/exit by 2x on Power9/Power10.
- Allow firmware to tell us whether to disable the entry and uaccess
flushes on Power10 or later CPUs.
- Add BPF_PROBE_MEM support for 32 and 64-bit BPF jits.
- Several fixes and improvements to our hard lockup watchdog.
- Activate HAVE_DYNAMIC_FTRACE_WITH_REGS on 32-bit.
- Allow building the 64-bit Book3S kernel without hash MMU support, ie.
Radix only.
- Add KUAP (SMAP) support for 40x, 44x, 8xx, Book3E (64-bit).
- Add new encodings for perf_mem_data_src.mem_hops field, and use them
on Power10.
- A series of small performance improvements to 64-bit interrupt entry.
- Several commits fixing issues when building with the clang integrated
assembler.
- Many other small features and fixes.
Thanks to Alan Modra, Alexey Kardashevskiy, Ammar Faizi, Anders Roxell,
Arnd Bergmann, Athira Rajeev, Cédric Le Goater, Christophe JAILLET,
Christophe Leroy, Christoph Hellwig, Daniel Axtens, David Yang, Erhard
Furtner, Fabiano Rosas, Greg Kroah-Hartman, Guo Ren, Hari Bathini, Jason
Wang, Joel Stanley, Julia Lawall, Kajol Jain, Kees Cook, Laurent Dufour,
Madhavan Srinivasan, Mark Brown, Minghao Chi, Nageswara R Sastry, Naresh
Kamboju, Nathan Chancellor, Nathan Lynch, Nicholas Piggin, Nick Child,
Oliver O'Halloran, Peiwei Hu, Randy Dunlap, Ravi Bangoria, Rob Herring,
Russell Currey, Sachin Sant, Sean Christopherson, Segher Boessenkool,
Thadeu Lima de Souza Cascardo, Tyrel Datwyler, Xiang wangx, and Yang
Guang.
* tag 'powerpc-5.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (240 commits)
powerpc/xmon: Dump XIVE information for online-only processors.
powerpc/opal: use default_groups in kobj_type
powerpc/cacheinfo: use default_groups in kobj_type
powerpc/sched: Remove unused TASK_SIZE_OF
powerpc/xive: Add missing null check after calling kmalloc
powerpc/floppy: Remove usage of the deprecated "pci-dma-compat.h" API
selftests/powerpc: Add a test of sigreturning to an unaligned address
powerpc/64s: Use EMIT_WARN_ENTRY for SRR debug warnings
powerpc/64s: Mask NIP before checking against SRR0
powerpc/perf: Fix spelling of "its"
powerpc/32: Fix boot failure with GCC latent entropy plugin
powerpc/code-patching: Replace patch_instruction() by ppc_inst_write() in selftests
powerpc/code-patching: Move code patching selftests in its own file
powerpc/code-patching: Move instr_is_branch_{i/b}form() in code-patching.h
powerpc/code-patching: Move patch_exception() outside code-patching.c
powerpc/code-patching: Use test_trampoline for prefixed patch test
powerpc/code-patching: Fix patch_branch() return on out-of-range failure
powerpc/code-patching: Reorganise do_patch_instruction() to ease error handling
powerpc/code-patching: Fix unmap_patch_area() error handling
powerpc/code-patching: Fix error handling in do_patch_instruction()
...
On PPC64 with KUAP enabled, any kernel code which wants to
access userspace needs to be surrounded by disable-enable KUAP.
But that is not happening for BPF_PROBE_MEM load instruction.
So, when BPF program tries to access invalid userspace address,
page-fault handler considers it as bad KUAP fault:
Kernel attempted to read user page (d0000000) - exploit attempt? (uid: 0)
Considering the fact that PTR_TO_BTF_ID (which uses BPF_PROBE_MEM
mode) could either be a valid kernel pointer or NULL but should
never be a pointer to userspace address, execute BPF_PROBE_MEM load
only if addr is kernel address, otherwise set dst_reg=0 and move on.
This will catch NULL, valid or invalid userspace pointers. Only bad
kernel pointer will be handled by BPF exception table.
[Alexei suggested for x86]
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211012123056.485795-7-hbathini@linux.ibm.com
BPF load instruction with BPF_PROBE_MEM mode can cause a fault
inside kernel. Append exception table for such instructions
within BPF program.
Unlike other archs which uses extable 'fixup' field to pass dest_reg
and nip, BPF exception table on PowerPC follows the generic PowerPC
exception table design, where it populates both fixup and extable
sections within BPF program. fixup section contains two instructions,
first instruction clears dest_reg and 2nd jumps to next instruction
in the BPF code. extable 'insn' field contains relative offset of
the instruction and 'fixup' field contains relative offset of the
fixup entry. Example layout of BPF program with extable present:
+------------------+
| |
| |
0x4020 -->| ld r27,4(r3) |
| |
| |
0x40ac -->| lwz r3,0(r4) |
| |
| |
|------------------|
0x4280 -->| li r27,0 | \ fixup entry
| b 0x4024 | /
0x4288 -->| li r3,0 |
| b 0x40b0 |
|------------------|
0x4290 -->| insn=0xfffffd90 | \ extable entry
| fixup=0xffffffec | /
0x4298 -->| insn=0xfffffe14 |
| fixup=0xffffffec |
+------------------+
(Addresses shown here are chosen random, not real)
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211012123056.485795-6-hbathini@linux.ibm.com
In case of extra_pass, usual JIT passes are always skipped. So,
extra_pass is always false while calling bpf_jit_build_body() and
can be removed.
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211012123056.485795-3-hbathini@linux.ibm.com
In the current code, the actual max tail call count is 33 which is greater
than MAX_TAIL_CALL_CNT (defined as 32). The actual limit is not consistent
with the meaning of MAX_TAIL_CALL_CNT and thus confusing at first glance.
We can see the historical evolution from commit 04fd61ab36 ("bpf: allow
bpf programs to tail-call other bpf programs") and commit f9dabe016b
("bpf: Undo off-by-one in interpreter tail call count limit"). In order
to avoid changing existing behavior, the actual limit is 33 now, this is
reasonable.
After commit 874be05f52 ("bpf, tests: Add tail call test suite"), we can
see there exists failed testcase.
On all archs when CONFIG_BPF_JIT_ALWAYS_ON is not set:
# echo 0 > /proc/sys/net/core/bpf_jit_enable
# modprobe test_bpf
# dmesg | grep -w FAIL
Tail call error path, max count reached jited:0 ret 34 != 33 FAIL
On some archs:
# echo 1 > /proc/sys/net/core/bpf_jit_enable
# modprobe test_bpf
# dmesg | grep -w FAIL
Tail call error path, max count reached jited:1 ret 34 != 33 FAIL
Although the above failed testcase has been fixed in commit 18935a72eb
("bpf/tests: Fix error in tail call limit tests"), it would still be good
to change the value of MAX_TAIL_CALL_CNT from 32 to 33 to make the code
more readable.
The 32-bit x86 JIT was using a limit of 32, just fix the wrong comments and
limit to 33 tail calls as the constant MAX_TAIL_CALL_CNT updated. For the
mips64 JIT, use "ori" instead of "addiu" as suggested by Johan Almbladh.
For the riscv JIT, use RV_REG_TCC directly to save one register move as
suggested by Björn Töpel. For the other implementations, no function changes,
it does not change the current limit 33, the new value of MAX_TAIL_CALL_CNT
can reflect the actual max tail call count, the related tail call testcases
in test_bpf module and selftests can work well for the interpreter and the
JIT.
Here are the test results on x86_64:
# uname -m
x86_64
# echo 0 > /proc/sys/net/core/bpf_jit_enable
# modprobe test_bpf test_suite=test_tail_calls
# dmesg | tail -1
test_bpf: test_tail_calls: Summary: 8 PASSED, 0 FAILED, [0/8 JIT'ed]
# rmmod test_bpf
# echo 1 > /proc/sys/net/core/bpf_jit_enable
# modprobe test_bpf test_suite=test_tail_calls
# dmesg | tail -1
test_bpf: test_tail_calls: Summary: 8 PASSED, 0 FAILED, [8/8 JIT'ed]
# rmmod test_bpf
# ./test_progs -t tailcalls
#142 tailcalls:OK
Summary: 1/11 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Björn Töpel <bjorn@kernel.org>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/1636075800-3264-1-git-send-email-yangtiezhu@loongson.cn
Emit similar instruction sequences to commit a048a07d7f
("powerpc/64s: Add support for a store forwarding barrier at kernel
entry/exit") when encountering BPF_NOSPEC.
Mitigations are enabled depending on what the firmware advertises. In
particular, we do not gate these mitigations based on current settings,
just like in x86. Due to this, we don't need to take any action if
mitigations are enabled or disabled at runtime.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/956570cbc191cd41f8274bed48ee757a86dac62a.1633464148.git.naveen.n.rao@linux.vnet.ibm.com
We aren't handling subtraction involving an immediate value of
0x80000000 properly. Fix the same.
Fixes: 156d0e290e ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Fold in fix from Naveen to use imm <= 32768]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fc4b1276eb10761fd7ce0814c8dd089da2815251.1633464148.git.naveen.n.rao@linux.vnet.ibm.com
Only ignore the operation if dividing by 1.
Fixes: 156d0e290e ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c674ca18c3046885602caebb326213731c675d06.1633464148.git.naveen.n.rao@linux.vnet.ibm.com
Add checks to ensure that we never emit branch instructions with
truncated branch offsets.
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/71d33a6b7603ec1013c9734dd8bdd4ff5e929142.1633464148.git.naveen.n.rao@linux.vnet.ibm.com
In case of JITs, each of the JIT backends compiles the BPF nospec instruction
/either/ to a machine instruction which emits a speculation barrier /or/ to
/no/ machine instruction in case the underlying architecture is not affected
by Speculative Store Bypass or has different mitigations in place already.
This covers both x86 and (implicitly) arm64: In case of x86, we use 'lfence'
instruction for mitigation. In case of arm64, we rely on the firmware mitigation
as controlled via the ssbd kernel parameter. Whenever the mitigation is enabled,
it works for all of the kernel code with no need to provide any additional
instructions here (hence only comment in arm64 JIT). Other archs can follow
as needed. The BPF nospec instruction is specifically targeting Spectre v4
since i) we don't use a serialization barrier for the Spectre v1 case, and
ii) mitigation instructions for v1 and v4 might be different on some archs.
The BPF nospec is required for a future commit, where the BPF verifier does
annotate intermediate BPF programs with speculation barriers.
Co-developed-by: Piotr Krysiuk <piotras@gmail.com>
Co-developed-by: Benedict Schlueter <benedict.schlueter@rub.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Piotr Krysiuk <piotras@gmail.com>
Signed-off-by: Benedict Schlueter <benedict.schlueter@rub.de>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Commit 91c960b005 ("bpf: Rename BPF_XADD and prepare to encode other
atomics in .imm") converted BPF_XADD to BPF_ATOMIC and added a way to
distinguish instructions based on the immediate field. Existing JIT
implementations were updated to check for the immediate field and to
reject programs utilizing anything more than BPF_ADD (such as BPF_FETCH)
in the immediate field.
However, the check added to powerpc64 JIT did not look at the correct
BPF instruction. Due to this, such programs would be accepted and
incorrectly JIT'ed resulting in soft lockups, as seen with the atomic
bounds test. Fix this by looking at the correct immediate value.
Fixes: 91c960b005 ("bpf: Rename BPF_XADD and prepare to encode other atomics in .imm")
Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4117b430ffaa8cd7af042496f87fd7539e4f17fd.1625145429.git.naveen.n.rao@linux.vnet.ibm.com
blrl corrupts the link stack. Instead use bctrl when making function
calls from BPF programs.
Reported-by: Anton Blanchard <anton@ozlabs.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210609090024.1446800-1-naveen.n.rao@linux.vnet.ibm.com
A subsequent patch will add additional atomic operations. These new
operations will use the same opcode field as the existing XADD, with
the immediate discriminating different operations.
In preparation, rename the instruction mode BPF_ATOMIC and start
calling the zero immediate BPF_ADD.
This is possible (doesn't break existing valid BPF progs) because the
immediate field is currently reserved MBZ and BPF_ADD is zero.
All uses are removed from the tree but the BPF_XADD definition is
kept around to avoid breaking builds for people including kernel
headers.
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Björn Töpel <bjorn.topel@gmail.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-5-jackmanb@google.com
Move macro definitions of powerpc instructions from bpf_jit.h to
ppc-opcode.h and adopt the users of the macros accordingly. `PPC_MR()`
is defined twice in bpf_jit.h, remove the duplicate one.
Signed-off-by: Balamuruhan S <bala24@linux.ibm.com>
Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200624113038.908074-5-bala24@linux.ibm.com
Remove duplicate macro definitions from bpf_jit.h and reuse the macros
from ppc-opcode.h
Signed-off-by: Balamuruhan S <bala24@linux.ibm.com>
Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200624113038.908074-4-bala24@linux.ibm.com
We have seen many crashes on powerpc hosts while loading bpf programs.
The problem here is that bpf_int_jit_compile() does a first pass
to compute the program length.
Then it allocates memory to store the generated program and
calls bpf_jit_build_body() a second time (and a third time
later)
What I have observed is that the second bpf_jit_build_body()
could end up using few more words than expected.
If bpf_jit_binary_alloc() put the space for the program
at the end of the allocated page, we then write on
a non mapped memory.
It appears that bpf_jit_emit_tail_call() calls
bpf_jit_emit_common_epilogue() while ctx->seen might not
be stable.
Only after the second pass we can be sure ctx->seen wont be changed.
Trying to avoid a second pass seems quite complex and probably
not worth it.
Fixes: ce0761419f ("powerpc/bpf: Implement support for tail calls")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191101033444.143741-1-edumazet@google.com
Pull networking fixes from David Miller:
"Lots of bug fixes here:
1) Out of bounds access in __bpf_skc_lookup, from Lorenz Bauer.
2) Fix rate reporting in cfg80211_calculate_bitrate_he(), from John
Crispin.
3) Use after free in psock backlog workqueue, from John Fastabend.
4) Fix source port matching in fdb peer flow rule of mlx5, from Raed
Salem.
5) Use atomic_inc_not_zero() in fl6_sock_lookup(), from Eric Dumazet.
6) Network header needs to be set for packet redirect in nfp, from
John Hurley.
7) Fix udp zerocopy refcnt, from Willem de Bruijn.
8) Don't assume linear buffers in vxlan and geneve error handlers,
from Stefano Brivio.
9) Fix TOS matching in mlxsw, from Jiri Pirko.
10) More SCTP cookie memory leak fixes, from Neil Horman.
11) Fix VLAN filtering in rtl8366, from Linus Walluij.
12) Various TCP SACK payload size and fragmentation memory limit fixes
from Eric Dumazet.
13) Use after free in pneigh_get_next(), also from Eric Dumazet.
14) LAPB control block leak fix from Jeremy Sowden"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (145 commits)
lapb: fixed leak of control-blocks.
tipc: purge deferredq list for each grp member in tipc_group_delete
ax25: fix inconsistent lock state in ax25_destroy_timer
neigh: fix use-after-free read in pneigh_get_next
tcp: fix compile error if !CONFIG_SYSCTL
hv_sock: Suppress bogus "may be used uninitialized" warnings
be2net: Fix number of Rx queues used for flow hashing
net: handle 802.1P vlan 0 packets properly
tcp: enforce tcp_min_snd_mss in tcp_mtu_probing()
tcp: add tcp_min_snd_mss sysctl
tcp: tcp_fragment() should apply sane memory limits
tcp: limit payload size of sacked skbs
Revert "net: phylink: set the autoneg state in phylink_phy_change"
bpf: fix nested bpf tracepoints with per-cpu data
bpf: Fix out of bounds memory access in bpf_sk_storage
vsock/virtio: set SOCK_DONE on peer shutdown
net: dsa: rtl8366: Fix up VLAN filtering
net: phylink: set the autoneg state in phylink_phy_change
net: add high_order_alloc_disable sysctl/static key
tcp: add tcp_tx_skb_cache sysctl
...
BPF_ALU64 div/mod operations are currently using signed division, unlike
BPF_ALU32 operations. Fix the same. DIV64 and MOD64 overflow tests pass
with this fix.
Fixes: 156d0e290e ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 of the license
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 315 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Yauheni Kaliuta pointed out that PTR_TO_STACK store/load verifier test
was failing on powerpc64 BE, and rightfully indicated that the PPC_LD()
macro is not masking away the last two bits of the offset per the ISA,
resulting in the generation of 'lwa' instruction instead of the intended
'ld' instruction.
Segher also pointed out that we can't simply mask away the last two bits
as that will result in loading/storing from/to a memory location that
was not intended.
This patch addresses this by using ldx/stdx if the offset is not
word-aligned. We load the offset into a temporary register (TMP_REG_2)
and use that as the index register in a subsequent ldx/stdx. We fix
PPC_LD() macro to mask off the last two bits, but enhance PPC_BPF_LL()
and PPC_BPF_STL() to factor in the offset value and generate the proper
instruction sequence. We also convert all existing users of PPC_LD() and
PPC_STD() to use these macros. All existing uses of these macros have
been audited to ensure that TMP_REG_2 can be clobbered.
Fixes: 156d0e290e ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF")
Cc: stable@vger.kernel.org # v4.9+
Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This adds support for generating bpf line info for
JITed programs.
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch implements code-gen for new JMP32 instructions on ppc.
For JMP32 | JSET, instruction encoding for PPC_RLWINM_DOT is added to check
the result of ANDing low 32-bit of operands.
Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-12-11
The following pull-request contains BPF updates for your *net-next* tree.
It has three minor merge conflicts, resolutions:
1) tools/testing/selftests/bpf/test_verifier.c
Take first chunk with alignment_prevented_execution.
2) net/core/filter.c
[...]
case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
case bpf_ctx_range(struct __sk_buff, wire_len):
return false;
[...]
3) include/uapi/linux/bpf.h
Take the second chunk for the two cases each.
The main changes are:
1) Add support for BPF line info via BTF and extend libbpf as well
as bpftool's program dump to annotate output with BPF C code to
facilitate debugging and introspection, from Martin.
2) Add support for BPF_ALU | BPF_ARSH | BPF_{K,X} in interpreter
and all JIT backends, from Jiong.
3) Improve BPF test coverage on archs with no efficient unaligned
access by adding an "any alignment" flag to the BPF program load
to forcefully disable verifier alignment checks, from David.
4) Add a new bpf_prog_test_run_xattr() API to libbpf which allows for
proper use of BPF_PROG_TEST_RUN with data_out, from Lorenz.
5) Extend tc BPF programs to use a new __sk_buff field called wire_len
for more accurate accounting of packets going to wire, from Petar.
6) Improve bpftool to allow dumping the trace pipe from it and add
several improvements in bash completion and map/prog dump,
from Quentin.
7) Optimize arm64 BPF JIT to always emit movn/movk/movk sequence for
kernel addresses and add a dedicated BPF JIT backend allocator,
from Ard.
8) Add a BPF helper function for IR remotes to report mouse movements,
from Sean.
9) Various cleanups in BPF prog dump e.g. to make UAPI bpf_prog_info
member naming consistent with existing conventions, from Yonghong
and Song.
10) Misc cleanups and improvements in allowing to pass interface name
via cmdline for xdp1 BPF example, from Matteo.
11) Fix a potential segfault in BPF sample loader's kprobes handling,
from Daniel T.
12) Fix SPDX license in libbpf's README.rst, from Andrey.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Once the JITed images for each function in a multi-function program
are generated after the first three JIT passes, we only need to fix
the target address for the branch instruction corresponding to each
bpf-to-bpf function call.
This introduces the following optimizations for reducing the work
done by the JIT compiler when handling multi-function programs:
[1] Instead of doing two extra passes to fix the bpf function calls,
do just one as that would be sufficient.
[2] During the extra pass, only overwrite the instruction sequences
for the bpf-to-bpf function calls as everything else would still
remain exactly the same. This also reduces the number of writes
to the JITed image.
[3] Do not regenerate the prologue and the epilogue during the extra
pass as that would be redundant.
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Make fetching of the BPF call address from ppc64 JIT generic. ppc64
was using a slightly different variant rather than through the insns'
imm field encoding as the target address would not fit into that space.
Therefore, the target subprog number was encoded into the insns' offset
and fetched through fp->aux->func[off]->bpf_func instead. Given there
are other JITs with this issue and the mechanism of fetching the address
is JIT-generic, move it into the core as a helper instead. On the JIT
side, we get information on whether the retrieved address is a fixed
one, that is, not changing through JIT passes, or a dynamic one. For
the former, JITs can optimize their imm emission because this doesn't
change jump offsets throughout JIT process.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Sandipan Das <sandipan@linux.ibm.com>
Tested-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Notable changes:
- A fix for a bug in our page table fragment allocator, where a page table page
could be freed and reallocated for something else while still in use, leading
to memory corruption etc. The fix reuses pt_mm in struct page (x86 only) for
a powerpc only refcount.
- Fixes to our pkey support. Several are user-visible changes, but bring us in
to line with x86 behaviour and/or fix outright bugs. Thanks to Florian Weimer
for reporting many of these.
- A series to improve the hvc driver & related OPAL console code, which have
been seen to cause hardlockups at times. The hvc driver changes in particular
have been in linux-next for ~month.
- Increase our MAX_PHYSMEM_BITS to 128TB when SPARSEMEM_VMEMMAP=y.
- Remove Power8 DD1 and Power9 DD1 support, neither chip should be in use
anywhere other than as a paper weight.
- An optimised memcmp implementation using Power7-or-later VMX instructions
- Support for barrier_nospec on some NXP CPUs.
- Support for flushing the count cache on context switch on some IBM CPUs
(controlled by firmware), as a Spectre v2 mitigation.
- A series to enhance the information we print on unhandled signals to bring it
into line with other arches, including showing the offending VMA and dumping
the instructions around the fault.
Thanks to:
Aaro Koskinen, Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Alexey
Spirkov, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar,
Arnd Bergmann, Bartosz Golaszewski, Benjamin Herrenschmidt, Bharat Bhushan,
Bjoern Noetel, Boqun Feng, Breno Leitao, Bryant G. Ly, Camelia Groza,
Christophe Leroy, Christoph Hellwig, Cyril Bur, Dan Carpenter, Daniel Klamt,
Darren Stevens, Dave Young, David Gibson, Diana Craciun, Finn Thain, Florian
Weimer, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Geoff Levand,
Guenter Roeck, Gustavo Romero, Haren Myneni, Hari Bathini, Joel Stanley,
Jonathan Neuschäfer, Kees Cook, Madhavan Srinivasan, Mahesh Salgaonkar, Markus
Elfring, Mathieu Malaterre, Mauro S. M. Rodrigues, Michael Hanselmann, Michael
Neuling, Michael Schmitz, Mukesh Ojha, Murilo Opsfelder Araujo, Nicholas
Piggin, Parth Y Shah, Paul Mackerras, Paul Menzel, Ram Pai, Randy Dunlap,
Rashmica Gupta, Reza Arbab, Rodrigo R. Galvao, Russell Currey, Sam Bobroff,
Scott Wood, Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stan Johnson,
Thiago Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vasant Hegde, Venkat Rao
B, zhong jiang.
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Merge tag 'powerpc-4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Notable changes:
- A fix for a bug in our page table fragment allocator, where a page
table page could be freed and reallocated for something else while
still in use, leading to memory corruption etc. The fix reuses
pt_mm in struct page (x86 only) for a powerpc only refcount.
- Fixes to our pkey support. Several are user-visible changes, but
bring us in to line with x86 behaviour and/or fix outright bugs.
Thanks to Florian Weimer for reporting many of these.
- A series to improve the hvc driver & related OPAL console code,
which have been seen to cause hardlockups at times. The hvc driver
changes in particular have been in linux-next for ~month.
- Increase our MAX_PHYSMEM_BITS to 128TB when SPARSEMEM_VMEMMAP=y.
- Remove Power8 DD1 and Power9 DD1 support, neither chip should be in
use anywhere other than as a paper weight.
- An optimised memcmp implementation using Power7-or-later VMX
instructions
- Support for barrier_nospec on some NXP CPUs.
- Support for flushing the count cache on context switch on some IBM
CPUs (controlled by firmware), as a Spectre v2 mitigation.
- A series to enhance the information we print on unhandled signals
to bring it into line with other arches, including showing the
offending VMA and dumping the instructions around the fault.
Thanks to: Aaro Koskinen, Akshay Adiga, Alastair D'Silva, Alexey
Kardashevskiy, Alexey Spirkov, Alistair Popple, Andrew Donnellan,
Aneesh Kumar K.V, Anju T Sudhakar, Arnd Bergmann, Bartosz Golaszewski,
Benjamin Herrenschmidt, Bharat Bhushan, Bjoern Noetel, Boqun Feng,
Breno Leitao, Bryant G. Ly, Camelia Groza, Christophe Leroy, Christoph
Hellwig, Cyril Bur, Dan Carpenter, Daniel Klamt, Darren Stevens, Dave
Young, David Gibson, Diana Craciun, Finn Thain, Florian Weimer,
Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven, Geoff Levand,
Guenter Roeck, Gustavo Romero, Haren Myneni, Hari Bathini, Joel
Stanley, Jonathan Neuschäfer, Kees Cook, Madhavan Srinivasan, Mahesh
Salgaonkar, Markus Elfring, Mathieu Malaterre, Mauro S. M. Rodrigues,
Michael Hanselmann, Michael Neuling, Michael Schmitz, Mukesh Ojha,
Murilo Opsfelder Araujo, Nicholas Piggin, Parth Y Shah, Paul
Mackerras, Paul Menzel, Ram Pai, Randy Dunlap, Rashmica Gupta, Reza
Arbab, Rodrigo R. Galvao, Russell Currey, Sam Bobroff, Scott Wood,
Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stan Johnson, Thiago
Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vasant Hegde, Venkat
Rao, zhong jiang"
* tag 'powerpc-4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (234 commits)
powerpc/mm/book3s/radix: Add mapping statistics
powerpc/uaccess: Enable get_user(u64, *p) on 32-bit
powerpc/mm/hash: Remove unnecessary do { } while(0) loop
powerpc/64s: move machine check SLB flushing to mm/slb.c
powerpc/powernv/idle: Fix build error
powerpc/mm/tlbflush: update the mmu_gather page size while iterating address range
powerpc/mm: remove warning about ‘type’ being set
powerpc/32: Include setup.h header file to fix warnings
powerpc: Move `path` variable inside DEBUG_PROM
powerpc/powermac: Make some functions static
powerpc/powermac: Remove variable x that's never read
cxl: remove a dead branch
powerpc/powermac: Add missing include of header pmac.h
powerpc/kexec: Use common error handling code in setup_new_fdt()
powerpc/xmon: Add address lookup for percpu symbols
powerpc/mm: remove huge_pte_offset_and_shift() prototype
powerpc/lib: Use patch_site to patch copy_32 functions once cache is enabled
powerpc/pseries: Fix endianness while restoring of r3 in MCE handler.
powerpc/fadump: merge adjacent memory ranges to reduce PT_LOAD segements
powerpc/fadump: handle crash memory ranges array index overflow
...
This patch moves ASM_CONST() and stringify_in_c() into
dedicated asm-const.h, then cleans all related inclusions.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: asm-compat.h should include asm-const.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
