stuartl/linux-stable
1
0
Fork 0
mirror of https://kernel.googlesource.com/pub/scm/linux/kernel/git/stable/linux-stable.git synced 2025-09-13 11:07:46 +10:00
Code Issues Releases Wiki Activity
1,162,439 Commits 99 Branches 5,402 Tags 8.3 GiB
6039b8798f
Go to file
Peter Xu 6039b8798f mm/uffd: fix vma operation where start addr cuts part of vma 
commit 270aa01062 upstream.

Patch series "mm/uffd: Fix vma merge/split", v2.

This series contains two patches that fix vma merge/split for userfaultfd
on two separate issues.

Patch 1 fixes a regression since 6.1+ due to something we overlooked when
converting to maple tree apis.  The plan is we use patch 1 to replace the
commit "2f628010799e (mm: userfaultfd: avoid passing an invalid range to
vma_merge())" in mm-hostfixes-unstable tree if possible, so as to bring
uffd vma operations back aligned with the rest code again.

Patch 2 fixes a long standing issue that vma can be left unmerged even if
we can for either uffd register or unregister.

Many thanks to Lorenzo on either noticing this issue from the assert
movement patch, looking at this problem, and also provided a reproducer on
the unmerged vma issue [1].

[1] https://gist.github.com/lorenzo-stoakes/a11a10f5f479e7a977fc456331266e0e


This patch (of 2):

It seems vma merging with uffd paths is broken with either
register/unregister, where right now we can feed wrong parameters to
vma_merge() and it's found by recent patch which moved asserts upwards in
vma_merge() by Lorenzo Stoakes:

https://lore.kernel.org/all/ZFunF7DmMdK05MoF@FVFF77S0Q05N.cambridge.arm.com/

It's possible that "start" is contained within vma but not clamped to its
start.  We need to convert this into either "cannot merge" case or "can
merge" case 4 which permits subdivision of prev by assigning vma to prev.
As we loop, each subsequent VMA will be clamped to the start.

This patch will eliminate the report and make sure vma_merge() calls will
become legal again.

One thing to mention is that the "Fixes: 29417d292bd0" below is there only
to help explain where the warning can start to trigger, the real commit to
fix should be 69dbe6daf1.  Commit 29417d292b helps us to identify the
issue, but unfortunately we may want to keep it in Fixes too just to ease
kernel backporters for easier tracking.

Link: https://lkml.kernel.org/r/20230517190916.3429499-1-peterx@redhat.com
Link: https://lkml.kernel.org/r/20230517190916.3429499-2-peterx@redhat.com
Fixes: 69dbe6daf1 ("userfaultfd: use maple tree iterator to iterate VMAs")
Signed-off-by: Peter Xu <peterx@redhat.com>
Reported-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Closes: https://lore.kernel.org/all/ZFunF7DmMdK05MoF@FVFF77S0Q05N.cambridge.arm.com/
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[acsjakub: contextual change - keep call to mas_next()]
Cc: <linux-mm@kvack.org>
Signed-off-by: Jakub Acs <acsjakub@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-27 11:07:04 +01:00
arch um: let 'make clean' properly clean underlying SUBARCH as well 2025-06-04 14:40:26 +02:00
block scsi: sd_zbc: block: Respect bio vector limits for REPORT ZONES buffer 2025-05-22 14:10:06 +02:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2025-04-25 10:44:04 +02:00
crypto crypto: algif_hash - fix double free in hash_accept 2025-06-04 14:40:20 +02:00
Documentation serial: mctrl_gpio: split disable_ms into sync and no_sync APIs 2025-06-04 14:40:13 +02:00
drivers net: ethernet: ti: am65-cpsw: Lower random mac address error print to info 2025-06-04 14:40:26 +02:00
fs mm/uffd: fix vma operation where start addr cuts part of vma 2025-06-27 11:07:04 +01:00
include NFS: Avoid flushing data while holding directory locks in nfs_rename() 2025-06-04 14:40:26 +02:00
init sched/isolation: Make CONFIG_CPU_ISOLATION depend on CONFIG_SMP 2025-05-02 07:47:04 +02:00
io_uring io_uring: fix overflow resched cqe reordering 2025-06-04 14:40:20 +02:00
ipc
kernel fork: use pidfd_prepare() 2025-06-04 14:40:25 +02:00
lib crypto: lzo - Fix compression buffer overrun 2025-06-04 14:40:08 +02:00
LICENSES
mm mm/page_alloc.c: avoid infinite retries caused by cpuset race 2025-06-04 14:40:21 +02:00
net net_sched: hfsc: Address reentrant enqueue adding class to eltree twice 2025-06-04 14:40:25 +02:00
rust
samples samples/bpf: Fix compilation failure for samples/bpf on LoongArch Fedora 2025-06-04 14:40:02 +02:00
scripts kbuild: fix argument parsing in scripts/config 2025-06-04 14:40:06 +02:00
security smack: recognize ipv4 CIPSO w/o categories 2025-06-04 14:40:14 +02:00
sound ALSA: hda/realtek: Add quirk for Lenovo Yoga Pro 7 14ASP10 2025-06-04 14:40:21 +02:00
tools bpftool: Fix readlink usage in get_fd_type 2025-06-04 14:40:17 +02:00
usr
virt
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
.rustfmt.toml
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS sign-file,extract-cert: move common SSL helper functions to a header 2025-04-25 10:44:04 +02:00
Makefile Linux 6.1.141 2025-06-04 14:40:26 +02:00
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.