Linux kernel source tree
 
 
 
 
 
 
Go to file
Peter Collingbourne 2efbafb91e arm64: Also reset KASAN tag if page is not PG_mte_tagged
Consider the following sequence of events:

1) A page in a PROT_READ|PROT_WRITE VMA is faulted.
2) Page migration allocates a page with the KASAN allocator,
   causing it to receive a non-match-all tag, and uses it
   to replace the page faulted in 1.
3) The program uses mprotect() to enable PROT_MTE on the page faulted in 1.

As a result of step 3, we are left with a non-match-all tag for a page
with tags accessible to userspace, which can lead to the same kind of
tag check faults that commit e74a684680 ("arm64: Reset KASAN tag in
copy_highpage with HW tags only") intended to fix.

The general invariant that we have for pages in a VMA with VM_MTE_ALLOWED
is that they cannot have a non-match-all tag. As a result of step 2, the
invariant is broken. This means that the fix in the referenced commit
was incomplete and we also need to reset the tag for pages without
PG_mte_tagged.

Fixes: e5b8d92189 ("arm64: mte: reset the page tag in page->flags")
Cc: <stable@vger.kernel.org> # 5.15
Link: https://linux-review.googlesource.com/id/I7409cdd41acbcb215c2a7417c1e50d37b875beff
Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20230420210945.2313627-1-pcc@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-05-16 14:58:54 +01:00
Documentation - mailbox api: allow direct registration to a channel 2023-05-07 10:17:33 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
arch arm64: Also reset KASAN tag if page is not PG_mte_tagged 2023-05-16 14:58:54 +01:00
block for-6.4/block-2023-05-06 2023-05-06 08:28:58 -07:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto This push fixes the following problems: 2023-05-07 10:57:14 -07:00
drivers This push fixes the following problems: 2023-05-07 10:57:14 -07:00
fs 9 smb3 client fixes, mostly DFS or reconnect related 2023-05-07 10:46:21 -07:00
include - mailbox api: allow direct registration to a channel 2023-05-07 10:17:33 -07:00
init Objtool changes for v6.4: 2023-04-28 14:02:54 -07:00
io_uring for-6.4/io_uring-2023-05-07 2023-05-07 10:00:09 -07:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel Minor tracing updates: 2023-05-05 13:11:02 -07:00
lib A single fix for debugobjects: 2023-05-07 11:04:26 -07:00
mm Reinstate the dmapool changes which were accidentally removed by 2023-05-06 11:43:08 -07:00
net Including fixes from netfilter. 2023-05-05 19:12:01 -07:00
rust Rust changes for v6.4 2023-04-30 11:20:22 -07:00
samples LoongArch changes for v6.4 2023-05-04 12:40:16 -07:00
scripts Locking changes in v6.4: 2023-05-05 12:56:55 -07:00
security integrity-v6.4 2023-04-29 10:11:32 -07:00
sound sound fixes for 6.4-rc1 2023-05-06 08:07:11 -07:00
tools Disable building BPF based features by default for v6.4. 2023-05-07 11:32:18 -07:00
usr initramfs: Check negative timestamp to prevent broken cpio archive 2023-04-16 17:37:01 +09:00
virt s390: 2023-05-01 12:06:20 -07:00
.clang-format cxl for v6.4 2023-04-30 11:51:51 -07:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore linux-kselftest-kunit-6.4-rc1 2023-04-24 12:31:32 -07:00
.mailmap for-6.4/block-2023-05-06 2023-05-06 08:28:58 -07:00
.rustfmt.toml rust: add `.rustfmt.toml` 2022-09-28 09:02:20 +02:00
COPYING
CREDITS A handful of late-arriving documentation fixes, plus one Spanish 2023-05-05 13:16:42 -07:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Including fixes from netfilter. 2023-05-05 19:12:01 -07:00
Makefile Linux 6.4-rc1 2023-05-07 13:34:35 -07:00
README

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.