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| author | Alexei Starovoitov <ast@kernel.org> | 2022-09-26 20:30:40 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2022-09-26 20:31:02 -0700 |
| commit | 30b8fdbbe31b2422f46fcd6d3960e563affe76d7 (patch) | |
| tree | 4257dcd090e4aa3d9c55551abd6762aa9fdff21a /kernel/kprobes.c | |
| parent | bec217197b412d74168c6a42fc0f76d0cc9cad00 (diff) | |
| parent | 738c345b74b8d11edd01b6cee5628c6b8368d8ea (diff) | |
Merge branch 'bpf: Fixes for CONFIG_X86_KERNEL_IBT'
Jiri Olsa says:
====================
Martynas reported bpf_get_func_ip returning +4 address when
CONFIG_X86_KERNEL_IBT option is enabled and I found there are
some failing bpf tests when this option is enabled.
The CONFIG_X86_KERNEL_IBT option adds endbr instruction at the
function entry, so the idea is to 'fix' entry ip for kprobe_multi
and trampoline probes, because they are placed on the function
entry.
v5 changes:
- updated uapi/linux/bpf.h headers with comment for
bpf_get_func_ip returning 0 [Andrii]
- added acks
v4 changes:
- used get_kernel_nofault to read previous instruction [Peter]
- used movabs instruction in trampoline comment [Peter]
- renamed fentry_ip argument in kprobe_multi_link_handler [Peter]
v3 changes:
- using 'unused' bpf function to get IBT config option
into selftest skeleton
- rebased to current bpf-next/master
- added ack/review from Masami
v2 changes:
- change kprobes get_func_ip to return zero for kprobes
attached within the function body [Andrii]
- detect IBT config and properly test kprobe with offset
[Andrii]
v1 changes:
- read previous instruction in kprobe_multi link handler
and adjust entry_ip for CONFIG_X86_KERNEL_IBT option
- split first patch into 2 separate changes
- update changelogs
====================
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel/kprobes.c')
| -rw-r--r-- | kernel/kprobes.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 08350e35aba24..51adc3c945039 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1606,9 +1606,10 @@ int register_kprobe(struct kprobe *p) struct kprobe *old_p; struct module *probed_mod; kprobe_opcode_t *addr; + bool on_func_entry; /* Adjust probe address from symbol */ - addr = kprobe_addr(p); + addr = _kprobe_addr(p->addr, p->symbol_name, p->offset, &on_func_entry); if (IS_ERR(addr)) return PTR_ERR(addr); p->addr = addr; @@ -1628,6 +1629,9 @@ int register_kprobe(struct kprobe *p) mutex_lock(&kprobe_mutex); + if (on_func_entry) + p->flags |= KPROBE_FLAG_ON_FUNC_ENTRY; + old_p = get_kprobe(p->addr); if (old_p) { /* Since this may unoptimize 'old_p', locking 'text_mutex'. */ |