summaryrefslogtreecommitdiff
path: root/arch/arm/probes (follow)
Commit message (Collapse)AuthorAge
* ARM: 9139/1: kprobes: fix arch_init_kprobes() prototypeArnd Bergmann2021-11-02
| | | | | | | | | | | | | | | | | | | commit 1f323127cab086e4fd618981b1e5edc396eaf0f4 upstream. With extra warnings enabled, gcc complains about this function definition: arch/arm/probes/kprobes/core.c: In function 'arch_init_kprobes': arch/arm/probes/kprobes/core.c:465:12: warning: old-style function definition [-Wold-style-definition] 465 | int __init arch_init_kprobes() Link: https://lore.kernel.org/all/20201027093057.c685a14b386acacb3c449e3d@kernel.org/ Fixes: 24ba613c9d6c ("ARM kprobes: core code") Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: 9087/1: kprobes: test-thumb: fix for LLVM_IAS=1Nick Desaulniers2021-07-20
| | | | | | | | | | | | | | | | | | [ Upstream commit 8b95a7d90ce8160ac5cffd5bace6e2eba01a871e ] There's a few instructions that GAS infers operands but Clang doesn't; from what I can tell the Arm ARM doesn't say these are optional. F5.1.257 TBB, TBH T1 Halfword variant F5.1.238 STREXD T1 variant F5.1.84 LDREXD T1 variant Link: https://github.com/ClangBuiltLinux/linux/issues/1309 Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Jian Cai <jiancai@google.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org>
* arm: kprobes: Allow to handle reentered kprobe on single-steppingMasami Hiramatsu2021-07-11
| | | | | | | | | | | | | | | | | | | | | | | | | commit f3fbd7ec62dec1528fb8044034e2885f2b257941 upstream. This is arm port of commit 6a5022a56ac3 ("kprobes/x86: Allow to handle reentered kprobe on single-stepping") Since the FIQ handlers can interrupt in the single stepping (or preparing the single stepping, do_debug etc.), we should consider a kprobe is hit in the NMI handler. Even in that case, the kprobe is allowed to be reentered as same as the kprobes hit in kprobe handlers (KPROBE_HIT_ACTIVE or KPROBE_HIT_SSDONE). The real issue will happen when a kprobe hit while another reentered kprobe is processing (KPROBE_REENTER), because we already consumed a saved-area for the previous kprobe. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Jon Medhurst <tixy@linaro.org> Fixes: 24ba613c9d6c ("ARM kprobes: core code") Cc: stable@vger.kernel.org #v2.6.25~v4.11 Signed-off-by: huangshaobo <huangshaobo6@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: 9071/1: uprobes: Don't hook on thumb instructionsFredrik Strupe2021-04-28
| | | | | | | | | | | | | | | | | | | | commit d2f7eca60b29006285d57c7035539e33300e89e5 upstream. Since uprobes is not supported for thumb, check that the thumb bit is not set when matching the uprobes instruction hooks. The Arm UDF instructions used for uprobes triggering (UPROBE_SWBP_ARM_INSN and UPROBE_SS_ARM_INSN) coincidentally share the same encoding as a pair of unallocated 32-bit thumb instructions (not UDF) when the condition code is 0b1111 (0xf). This in effect makes it possible to trigger the uprobes functionality from thumb, and at that using two unallocated instructions which are not permanently undefined. Signed-off-by: Fredrik Strupe <fredrik@strupe.net> Cc: stable@vger.kernel.org Fixes: c7edc9e326d5 ("ARM: add uprobes support") Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: 8770/1: kprobes: Prohibit probing on optimized_callbackMasami Hiramatsu2018-05-26
| | | | | | | | | | | | | | | | commit 70948c05fdde0aac32f9667856a88725c192fa40 upstream. Prohibit probing on optimized_callback() because it is called from kprobes itself. If we put a kprobes on it, that will cause a recursive call loop. Mark it NOKPROBE_SYMBOL. Fixes: 0dc016dbd820 ("ARM: kprobes: enable OPTPROBES for ARM 32") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: 8769/1: kprobes: Fix to use get_kprobe_ctlblk after irq-disabedMasami Hiramatsu2018-05-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 69af7e23a6870df2ea6fa79ca16493d59b3eebeb upstream. Since get_kprobe_ctlblk() uses smp_processor_id() to access per-cpu variable, it hits smp_processor_id sanity check as below. [ 7.006928] BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1 [ 7.007859] caller is debug_smp_processor_id+0x20/0x24 [ 7.008438] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.16.0-rc1-00192-g4eb17253e4b5 #1 [ 7.008890] Hardware name: Generic DT based system [ 7.009917] [<c0313f0c>] (unwind_backtrace) from [<c030e6d8>] (show_stack+0x20/0x24) [ 7.010473] [<c030e6d8>] (show_stack) from [<c0c64694>] (dump_stack+0x84/0x98) [ 7.010990] [<c0c64694>] (dump_stack) from [<c071ca5c>] (check_preemption_disabled+0x138/0x13c) [ 7.011592] [<c071ca5c>] (check_preemption_disabled) from [<c071ca80>] (debug_smp_processor_id+0x20/0x24) [ 7.012214] [<c071ca80>] (debug_smp_processor_id) from [<c03335e0>] (optimized_callback+0x2c/0xe4) [ 7.013077] [<c03335e0>] (optimized_callback) from [<bf0021b0>] (0xbf0021b0) To fix this issue, call get_kprobe_ctlblk() right after irq-disabled since that disables preemption. Fixes: 0dc016dbd820 ("ARM: kprobes: enable OPTPROBES for ARM 32") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* arm: kprobes: Align stack to 8-bytes in test codeJon Medhurst2017-12-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 974310d047f3c7788a51d10c8d255eebdb1fa857 ] kprobes test cases need to have a stack that is aligned to an 8-byte boundary because they call other functions (and the ARM ABI mandates that alignment) and because test cases include 64-bit accesses to the stack. Unfortunately, GCC doesn't ensure this alignment for inline assembler and for the code in question seems to always misalign it by pushing just the LR register onto the stack. We therefore need to explicitly perform stack alignment at the start of each test case. Without this fix, some test cases will generate alignment faults on systems where alignment is enforced. Even if the kernel is configured to handle these faults in software, triggering them is ugly. It also exposes limitations in the fault handling code which doesn't cope with writes to the stack. E.g. when handling this instruction strd r6, [sp, #-64]! the fault handling code will write to a stack location below the SP value at the point the fault occurred, which coincides with where the exception handler has pushed the saved register context. This results in corruption of those registers. Signed-off-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* arm: kprobes: Fix the return address of multiple kretprobesMasami Hiramatsu2017-12-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 06553175f585b52509c7df37d6f4a50aacb7b211 ] This is arm port of commit 737480a0d525 ("kprobes/x86: Fix the return address of multiple kretprobes"). Fix the return address of subsequent kretprobes when multiple kretprobes are set on the same function. For example: # cd /sys/kernel/debug/tracing # echo "r:event1 sys_symlink" > kprobe_events # echo "r:event2 sys_symlink" >> kprobe_events # echo 1 > events/kprobes/enable # ln -s /tmp/foo /tmp/bar (without this patch) # cat trace | grep -v ^# ln-82 [000] dn.2 68.446525: event1: (kretprobe_trampoline+0x0/0x18 <- SyS_symlink) ln-82 [000] dn.2 68.447831: event2: (ret_fast_syscall+0x0/0x1c <- SyS_symlink) (with this patch) # cat trace | grep -v ^# ln-81 [000] dn.1 39.463469: event1: (ret_fast_syscall+0x0/0x1c <- SyS_symlink) ln-81 [000] dn.1 39.464701: event2: (ret_fast_syscall+0x0/0x1c <- SyS_symlink) Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: KUMANO Syuhei <kumano.prog@gmail.com> Signed-off-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: kprobes: Fix compilation error caused by superfluous '*'Jon Medhurst2015-02-10
| | | | | | | | | | | | | There is a superfluous '*' in the definition of kprobe_decode_insn_t which on older versions of GCC (4.2.4) causes the compilation error: In file included from arch/arm/probes/kprobes/core.c:37: arch/arm/probes/kprobes/core.h:43: error: '[*]' not allowed in other than a declaration Fix this by removing the unneeded character. Reported-by: Janusz Użycki <j.uzycki@elproma.com.pl> Signed-off-by: Jon Medhurst <tixy@linaro.org>
* ARM: kprobes: Eliminate test code's use of BX instruction on ARMv4 CPUsJon Medhurst2015-01-20
| | | | | | | Non-T variants of ARMv4 CPUs don't support the BX instruction so eliminate its use. Signed-off-by: Jon Medhurst <tixy@linaro.org>
* ARM: optprobes: execute instruction during restoring if possible.Wang Nan2015-01-14
| | | | | | | | | | | | | | | This patch removes software emulation or simulation for most of probed instructions. If the instruction doesn't use PC relative addressing, it will be translated into following instructions in the restore code in code template: ldmia {r0 - r14} // restore all instruction except PC <instruction> // direct execute the probed instruction b next_insn // branch to next instruction. Signed-off-by: Wang Nan <wangnan0@huawei.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Jon Medhurst <tixy@linaro.org>
* ARM: kprobes: check register usage for probed instruction.Wang Nan2015-01-13
| | | | | | | | | | | This patch utilizes the previously introduced checker to check register usage for probed ARM instruction and saves it in a mask. A further patch will use such information to avoid simulation or emulation. Signed-off-by: Wang Nan <wangnan0@huawei.com> Reviewed-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Jon Medhurst <tixy@linaro.org>
* ARM: kprobes: Fix unreliable MRS instruction testsJon Medhurst (Tixy)2015-01-13
| | | | | | | | For the instruction 'mrs Rn, cpsr' the resulting value of Rn can vary due to external factors we can't control. So get the test code to mask out these indeterminate bits. Signed-off-by: Jon Medhurst <tixy@linaro.org>
* ARM: kprobes: enable OPTPROBES for ARM 32Wang Nan2015-01-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduce kprobeopt for ARM 32. Limitations: - Currently only kernel compiled with ARM ISA is supported. - Offset between probe point and optinsn slot must not larger than 32MiB. Masami Hiramatsu suggests replacing 2 words, it will make things complex. Futher patch can make such optimization. Kprobe opt on ARM is relatively simpler than kprobe opt on x86 because ARM instruction is always 4 bytes aligned and 4 bytes long. This patch replace probed instruction by a 'b', branch to trampoline code and then calls optimized_callback(). optimized_callback() calls opt_pre_handler() to execute kprobe handler. It also emulate/simulate replaced instruction. When unregistering kprobe, the deferred manner of unoptimizer may leave branch instruction before optimizer is called. Different from x86_64, which only copy the probed insn after optprobe_template_end and reexecute them, this patch call singlestep to emulate/simulate the insn directly. Futher patch can optimize this behavior. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Will Deacon <will.deacon@arm.com> Reviewed-by: Jon Medhurst (Tixy) <tixy@linaro.org> Signed-off-by: Jon Medhurst <tixy@linaro.org>
* ARM: kprobes: Add test cases for stack consuming instructionsJon Medhurst (Tixy)2015-01-13
| | | | | | | | | | These have extra 'checker' functions associated with them so lets make sure those get covered by testing. As they may create uninitialised space on the stack we also update the test code to ensure such space is consistent between test runs. This is done by disabling interrupts in setup_test_context(). Signed-off-by: Jon Medhurst <tixy@linaro.org>
* ARM: kprobes: disallow probing stack consuming instructionsWang Nan2015-01-13
| | | | | | | | | | | This patch prohibits probing instructions for which the stack requirements are unable to be determined statically. Some test cases are found not work again after the modification, this patch also removes them. Signed-off-by: Wang Nan <wangnan0@huawei.com> Reviewed-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Jon Medhurst <tixy@linaro.org>
* ARM: kprobes: collects stack consumption for store instructionsWang Nan2015-01-13
| | | | | | | | | | This patch uses the previously introduced checker functionality on store instructions to record their stack consumption information to arch_probes_insn. Signed-off-by: Wang Nan <wangnan0@huawei.com> Reviewed-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Jon Medhurst <tixy@linaro.org>
* ARM: kprobes: introduces checkerWang Nan2015-01-09
| | | | | | | | | | | | This patch introdces 'checker' to decoding phase, and calls checkers when instruction decoding. This allows further decoding for specific instructions. This patch introduces a stub call of checkers in kprobe arch_prepare_kprobe() as an example and for further expansion. Signed-off-by: Wang Nan <wangnan0@huawei.com> Reviewed-by: Jon Medhurst <tixy@linaro.org> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Jon Medhurst <tixy@linaro.org>
* ARM: probes: Use correct action types for MOVW, SEV and WFIJon Medhurst2015-01-09
| | | | | | | | | | | This doesn't correct any bugs when probing these instructions but makes MOVW slightly faster and makes everything more symmetric with the Thumb instruction cases. We can also remove the now redundant PROBES_EMULATE_NONE and PROBES_SIMULATE_NOP actions. Signed-off-by: Jon Medhurst <tixy@linaro.org>
* ARM: probes: move all probe code to dedicate directoryWang Nan2015-01-09
In discussion on LKML (https://lkml.org/lkml/2014/11/28/158), Russell King suggests to move all probe related code to arch/arm/probes. This patch does the work. Due to dependency on 'arch/arm/kernel/patch.h', this patch also moves patch.h to 'arch/arm/include/asm/patch.h', and related '#include' directives are also midified to '#include <asm/patch.h>'. Following is an overview of this patch: ./arch/arm/kernel/ ./arch/arm/probes/ |-- Makefile |-- Makefile |-- probes-arm.c ==> |-- decode-arm.c |-- probes-arm.h ==> |-- decode-arm.h |-- probes-thumb.c ==> |-- decode-thumb.c |-- probes-thumb.h ==> |-- decode-thumb.h |-- probes.c ==> |-- decode.c |-- probes.h ==> |-- decode.h | |-- kprobes | | |-- Makefile |-- kprobes-arm.c ==> | |-- actions-arm.c |-- kprobes-common.c ==> | |-- actions-common.c |-- kprobes-thumb.c ==> | |-- actions-thumb.c |-- kprobes.c ==> | |-- core.c |-- kprobes.h ==> | |-- core.h |-- kprobes-test-arm.c ==> | |-- test-arm.c |-- kprobes-test.c ==> | |-- test-core.c |-- kprobes-test.h ==> | |-- test-core.h |-- kprobes-test-thumb.c ==> | `-- test-thumb.c | `-- uprobes | |-- Makefile |-- uprobes-arm.c ==> |-- actions-arm.c |-- uprobes.c ==> |-- core.c |-- uprobes.h ==> `-- core.h | `-- patch.h ==> arch/arm/include/asm/patch.h Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Jon Medhurst <tixy@linaro.org>
generated by cgit v1.2.3 (git 2.25.1) at 2026-01-18 21:30:06 +0000