DigiGoon/android_kernel_xiaomi_sm8350
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

uprobes: fix kernel info leak via "[uprobes]" vma

Browse source 
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@redhat.com/

Reported-by: Will Deacon <will@kernel.org>
Fixes: d4b3b6384f ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Oleg Nesterov 2024-10-07 19:46:01 +02:00 • committed by Greg Kroah-Hartman
parent 7fc8b76903
commit fe5e9182d3
1 changed files with 1 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
kernel/events/uprobes.c
View file

@ -1502,7 +1502,7 @@ static struct xol_area *__create_xol_area(unsigned long vaddr)
area->xol_mapping.name = "[uprobes]"; area->xol_mapping.name = "[uprobes]";
area->xol_mapping.pages = area->pages; 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]) if (!area->pages[0])
goto free_bitmap; goto free_bitmap;
area->pages[1] = NULL; area->pages[1] = NULL;