This is a note to let you know that I've just added the patch titled
uprobes: fix kernel info leak via "[uprobes]" vma
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
uprobes-fix-kernel-info-leak-via-uprobes-vma.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 85a993c6a12963e5f3c5712bafe8434991ba726c
Author: Oleg Nesterov <oleg@xxxxxxxxxx>
Date: Mon Oct 7 19:46:01 2024 +0200
uprobes: fix kernel info leak via "[uprobes]" vma
commit 34820304cc2cd1804ee1f8f3504ec77813d29c8e upstream.
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@xxxxxxxxxx/
Reported-by: Will Deacon <will@xxxxxxxxxx>
Fixes: d4b3b6384f98 ("uprobes/core: Allocate XOL slots for uprobes use")
Cc: stable@xxxxxxxxxxxxxxx
Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 8a5989d46c930..9ee25351cecac 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1494,7 +1494,7 @@ static struct xol_area *__create_xol_area(unsigned long vaddr)
area->xol_mapping.name = "[uprobes]";
area->xol_mapping.pages = area->pages;
- area->pages[0] = alloc_page(GFP_HIGHUSER);
+ area->pages[0] = alloc_page(GFP_HIGHUSER | __GFP_ZERO);
if (!area->pages[0])
goto free_bitmap;
area->pages[1] = NULL;
