diff options
| author | Jiri Olsa <jolsa@kernel.org> | 2025-02-12 23:04:33 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2025-03-06 12:22:45 +0100 |
| commit | fa6192adc32f4fdfe5b74edd5b210e12afd6ecc0 (patch) | |
| tree | 5f729a51506852be9e066fbce1414b2e653aaad7 /kernel | |
| parent | 05763885e327f0e257ee8b96b30ac1b95f7dd532 (diff) | |
uprobes/x86: Harden uretprobe syscall trampoline check
Jann reported a possible issue when trampoline_check_ip returns
address near the bottom of the address space that is allowed to
call into the syscall if uretprobes are not set up:
https://lore.kernel.org/bpf/202502081235.5A6F352985@keescook/T/#m9d416df341b8fbc11737dacbcd29f0054413cbbf
Though the mmap minimum address restrictions will typically prevent
creating mappings there, let's make sure uretprobe syscall checks
for that.
Fixes: ff474a78cef5 ("uprobe: Add uretprobe syscall to speed up return probe")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250212220433.3624297-1-jolsa@kernel.org
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/events/uprobes.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 921ad9162136..70c84b9d7be3 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -2169,8 +2169,8 @@ void uprobe_copy_process(struct task_struct *t, unsigned long flags) */ unsigned long uprobe_get_trampoline_vaddr(void) { + unsigned long trampoline_vaddr = UPROBE_NO_TRAMPOLINE_VADDR; struct xol_area *area; - unsigned long trampoline_vaddr = -1; /* Pairs with xol_add_vma() smp_store_release() */ area = READ_ONCE(current->mm->uprobes_state.xol_area); /* ^^^ */ |