diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2024-09-29 18:20:47 +0200 |
|---|---|---|
| committer | Masami Hiramatsu (Google) <mhiramat@kernel.org> | 2024-09-30 08:19:11 +0900 |
| commit | 34820304cc2cd1804ee1f8f3504ec77813d29c8e (patch) | |
| tree | a07b6e098d903343551b7f8d2e978ff2bf5efbe5 | |
| parent | ad46e8f95e931e113cb98253daf6d443ac244cde (diff) | |
uprobes: fix kernel info leak via "[uprobes]" vma
xol_add_vma() maps the uninitialized page allocated by __create_xol_area()
into userspace. On some architectures (x86) this memory is readable even
without VM_READ, VM_EXEC results in the same pgprot_t as VM_EXEC|VM_READ,
although this doesn't really matter, debugger can read this memory anyway.
Link: https://lore.kernel.org/all/20240929162047.GA12611@redhat.com/
Reported-by: Will Deacon <will@kernel.org>
Fixes: d4b3b6384f98 ("uprobes/core: Allocate XOL slots for uprobes use")
Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
| -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 2ec796e2f055..4b52cb2ae6d6 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1545,7 +1545,7 @@ static struct xol_area *__create_xol_area(unsigned long vaddr) if (!area->bitmap) goto free_area; - area->page = alloc_page(GFP_HIGHUSER); + area->page = alloc_page(GFP_HIGHUSER | __GFP_ZERO); if (!area->page) goto free_bitmap; |