From: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
The modes[] array contains pointers to modes on the connectors'
mode lists, which are protected by dev->mode_config.mutex.
Thus we need to extend modes[] the same protection or by the
time we use it the elements may already be pointing to
freed/reused memory.
Cc: stable(a)vger.kernel.org
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/10583
Signed-off-by: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
---
drivers/gpu/drm/drm_client_modeset.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_client_modeset.c b/drivers/gpu/drm/drm_client_modeset.c
index 871e4e2129d6..0683a129b362 100644
--- a/drivers/gpu/drm/drm_client_modeset.c
+++ b/drivers/gpu/drm/drm_client_modeset.c
@@ -777,6 +777,7 @@ int drm_client_modeset_probe(struct drm_client_dev *client, unsigned int width,
unsigned int total_modes_count = 0;
struct drm_client_offset *offsets;
unsigned int connector_count = 0;
+ /* points to modes protected by mode_config.mutex */
struct drm_display_mode **modes;
struct drm_crtc **crtcs;
int i, ret = 0;
@@ -845,7 +846,6 @@ int drm_client_modeset_probe(struct drm_client_dev *client, unsigned int width,
drm_client_pick_crtcs(client, connectors, connector_count,
crtcs, modes, 0, width, height);
}
- mutex_unlock(&dev->mode_config.mutex);
drm_client_modeset_release(client);
@@ -875,6 +875,7 @@ int drm_client_modeset_probe(struct drm_client_dev *client, unsigned int width,
modeset->y = offset->y;
}
}
+ mutex_unlock(&dev->mode_config.mutex);
mutex_unlock(&client->modeset_mutex);
out:
--
2.43.2
On 04.04.2024 19:02, Ritesh Harjani (IBM) wrote:
> It will be good to know what was the test which identified this though?
>
> -ritesh
Unfortunately syzkaller was not able to generate a reproducer for this
issue.
- Ukhin Mikhail.
There is code in the SCSI core that sets the SCMD_FAIL_IF_RECOVERING
flag but there is no code that clears this flag. Instead of only clearing
SCMD_INITIALIZED in scsi_end_request(), clear all flags. It is never
necessary to preserve any command flags inside scsi_end_request().
Cc: stable(a)vger.kernel.org
Fixes: 310bcaef6d7e ("scsi: core: Support failing requests while recovering")
Signed-off-by: Bart Van Assche <bvanassche(a)acm.org>
---
drivers/scsi/scsi_lib.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index ca48ba9a229a..2fc2b97777ca 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -633,10 +633,9 @@ static bool scsi_end_request(struct request *req, blk_status_t error,
if (blk_queue_add_random(q))
add_disk_randomness(req->q->disk);
- if (!blk_rq_is_passthrough(req)) {
- WARN_ON_ONCE(!(cmd->flags & SCMD_INITIALIZED));
- cmd->flags &= ~SCMD_INITIALIZED;
- }
+ WARN_ON_ONCE(!blk_rq_is_passthrough(req) &&
+ !(cmd->flags & SCMD_INITIALIZED));
+ cmd->flags = 0;
/*
* Calling rcu_barrier() is not necessary here because the
Fuzzing reports a possible deadlock in jbd2_log_wait_commit.
The problem occurs in ext4_ind_migrate due to an incorrect order of
unlocking of the journal and write semaphores - the order of unlocking
must be the reverse of the order of locking.
Found by Linux Verification Center (linuxtesting.org) with syzkaller.
Signed-off-by: Artem Sadovnikov <ancowi69(a)gmail.com>
---
fs/ext4/migrate.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c
index d98ac2af8199..a5e1492bbaaa 100644
--- a/fs/ext4/migrate.c
+++ b/fs/ext4/migrate.c
@@ -663,8 +663,8 @@ int ext4_ind_migrate(struct inode *inode)
if (unlikely(ret2 && !ret))
ret = ret2;
errout:
- ext4_journal_stop(handle);
up_write(&EXT4_I(inode)->i_data_sem);
+ ext4_journal_stop(handle);
out_unlock:
ext4_writepages_up_write(inode->i_sb, alloc_ctx);
return ret;
--
2.25.1
The quilt patch titled
Subject: x86/mm/pat: fix VM_PAT handling in COW mappings
has been removed from the -mm tree. Its filename was
x86-mm-pat-fix-vm_pat-handling-in-cow-mappings.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: David Hildenbrand <david(a)redhat.com>
Subject: x86/mm/pat: fix VM_PAT handling in COW mappings
Date: Wed, 3 Apr 2024 23:21:30 +0200
PAT handling won't do the right thing in COW mappings: the first PTE (or,
in fact, all PTEs) can be replaced during write faults to point at anon
folios. Reliably recovering the correct PFN and cachemode using
follow_phys() from PTEs will not work in COW mappings.
Using follow_phys(), we might just get the address+protection of the anon
folio (which is very wrong), or fail on swap/nonswap entries, failing
follow_phys() and triggering a WARN_ON_ONCE() in untrack_pfn() and
track_pfn_copy(), not properly calling free_pfn_range().
In free_pfn_range(), we either wouldn't call memtype_free() or would call
it with the wrong range, possibly leaking memory.
To fix that, let's update follow_phys() to refuse returning anon folios,
and fallback to using the stored PFN inside vma->vm_pgoff for COW mappings
if we run into that.
We will now properly handle untrack_pfn() with COW mappings, where we
don't need the cachemode. We'll have to fail fork()->track_pfn_copy() if
the first page was replaced by an anon folio, though: we'd have to store
the cachemode in the VMA to make this work, likely growing the VMA size.
For now, lets keep it simple and let track_pfn_copy() just fail in that
case: it would have failed in the past with swap/nonswap entries already,
and it would have done the wrong thing with anon folios.
Simple reproducer to trigger the WARN_ON_ONCE() in untrack_pfn():
<--- C reproducer --->
#include <stdio.h>
#include <sys/mman.h>
#include <unistd.h>
#include <liburing.h>
int main(void)
{
struct io_uring_params p = {};
int ring_fd;
size_t size;
char *map;
ring_fd = io_uring_setup(1, &p);
if (ring_fd < 0) {
perror("io_uring_setup");
return 1;
}
size = p.sq_off.array + p.sq_entries * sizeof(unsigned);
/* Map the submission queue ring MAP_PRIVATE */
map = mmap(0, size, PROT_READ | PROT_WRITE, MAP_PRIVATE,
ring_fd, IORING_OFF_SQ_RING);
if (map == MAP_FAILED) {
perror("mmap");
return 1;
}
/* We have at least one page. Let's COW it. */
*map = 0;
pause();
return 0;
}
<--- C reproducer --->
On a system with 16 GiB RAM and swap configured:
# ./iouring &
# memhog 16G
# killall iouring
[ 301.552930] ------------[ cut here ]------------
[ 301.553285] WARNING: CPU: 7 PID: 1402 at arch/x86/mm/pat/memtype.c:1060 untrack_pfn+0xf4/0x100
[ 301.553989] Modules linked in: binfmt_misc nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_g
[ 301.558232] CPU: 7 PID: 1402 Comm: iouring Not tainted 6.7.5-100.fc38.x86_64 #1
[ 301.558772] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebu4
[ 301.559569] RIP: 0010:untrack_pfn+0xf4/0x100
[ 301.559893] Code: 75 c4 eb cf 48 8b 43 10 8b a8 e8 00 00 00 3b 6b 28 74 b8 48 8b 7b 30 e8 ea 1a f7 000
[ 301.561189] RSP: 0018:ffffba2c0377fab8 EFLAGS: 00010282
[ 301.561590] RAX: 00000000ffffffea RBX: ffff9208c8ce9cc0 RCX: 000000010455e047
[ 301.562105] RDX: 07fffffff0eb1e0a RSI: 0000000000000000 RDI: ffff9208c391d200
[ 301.562628] RBP: 0000000000000000 R08: ffffba2c0377fab8 R09: 0000000000000000
[ 301.563145] R10: ffff9208d2292d50 R11: 0000000000000002 R12: 00007fea890e0000
[ 301.563669] R13: 0000000000000000 R14: ffffba2c0377fc08 R15: 0000000000000000
[ 301.564186] FS: 0000000000000000(0000) GS:ffff920c2fbc0000(0000) knlGS:0000000000000000
[ 301.564773] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 301.565197] CR2: 00007fea88ee8a20 CR3: 00000001033a8000 CR4: 0000000000750ef0
[ 301.565725] PKRU: 55555554
[ 301.565944] Call Trace:
[ 301.566148] <TASK>
[ 301.566325] ? untrack_pfn+0xf4/0x100
[ 301.566618] ? __warn+0x81/0x130
[ 301.566876] ? untrack_pfn+0xf4/0x100
[ 301.567163] ? report_bug+0x171/0x1a0
[ 301.567466] ? handle_bug+0x3c/0x80
[ 301.567743] ? exc_invalid_op+0x17/0x70
[ 301.568038] ? asm_exc_invalid_op+0x1a/0x20
[ 301.568363] ? untrack_pfn+0xf4/0x100
[ 301.568660] ? untrack_pfn+0x65/0x100
[ 301.568947] unmap_single_vma+0xa6/0xe0
[ 301.569247] unmap_vmas+0xb5/0x190
[ 301.569532] exit_mmap+0xec/0x340
[ 301.569801] __mmput+0x3e/0x130
[ 301.570051] do_exit+0x305/0xaf0
...
Link: https://lkml.kernel.org/r/20240403212131.929421-3-david@redhat.com
Signed-off-by: David Hildenbrand <david(a)redhat.com>
Reported-by: Wupeng Ma <mawupeng1(a)huawei.com>
Closes: https://lkml.kernel.org/r/20240227122814.3781907-1-mawupeng1@huawei.com
Fixes: b1a86e15dc03 ("x86, pat: remove the dependency on 'vm_pgoff' in track/untrack pfn vma routines")
Fixes: 5899329b1910 ("x86: PAT: implement track/untrack of pfnmap regions for x86 - v3")
Acked-by: Ingo Molnar <mingo(a)kernel.org>
Cc: Dave Hansen <dave.hansen(a)linux.intel.com>
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Borislav Petkov <bp(a)alien8.de>
Cc: "H. Peter Anvin" <hpa(a)zytor.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
arch/x86/mm/pat/memtype.c | 49 +++++++++++++++++++++++++-----------
mm/memory.c | 4 ++
2 files changed, 39 insertions(+), 14 deletions(-)
--- a/arch/x86/mm/pat/memtype.c~x86-mm-pat-fix-vm_pat-handling-in-cow-mappings
+++ a/arch/x86/mm/pat/memtype.c
@@ -947,6 +947,38 @@ static void free_pfn_range(u64 paddr, un
memtype_free(paddr, paddr + size);
}
+static int get_pat_info(struct vm_area_struct *vma, resource_size_t *paddr,
+ pgprot_t *pgprot)
+{
+ unsigned long prot;
+
+ VM_WARN_ON_ONCE(!(vma->vm_flags & VM_PAT));
+
+ /*
+ * We need the starting PFN and cachemode used for track_pfn_remap()
+ * that covered the whole VMA. For most mappings, we can obtain that
+ * information from the page tables. For COW mappings, we might now
+ * suddenly have anon folios mapped and follow_phys() will fail.
+ *
+ * Fallback to using vma->vm_pgoff, see remap_pfn_range_notrack(), to
+ * detect the PFN. If we need the cachemode as well, we're out of luck
+ * for now and have to fail fork().
+ */
+ if (!follow_phys(vma, vma->vm_start, 0, &prot, paddr)) {
+ if (pgprot)
+ *pgprot = __pgprot(prot);
+ return 0;
+ }
+ if (is_cow_mapping(vma->vm_flags)) {
+ if (pgprot)
+ return -EINVAL;
+ *paddr = (resource_size_t)vma->vm_pgoff << PAGE_SHIFT;
+ return 0;
+ }
+ WARN_ON_ONCE(1);
+ return -EINVAL;
+}
+
/*
* track_pfn_copy is called when vma that is covering the pfnmap gets
* copied through copy_page_range().
@@ -957,20 +989,13 @@ static void free_pfn_range(u64 paddr, un
int track_pfn_copy(struct vm_area_struct *vma)
{
resource_size_t paddr;
- unsigned long prot;
unsigned long vma_size = vma->vm_end - vma->vm_start;
pgprot_t pgprot;
if (vma->vm_flags & VM_PAT) {
- /*
- * reserve the whole chunk covered by vma. We need the
- * starting address and protection from pte.
- */
- if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) {
- WARN_ON_ONCE(1);
+ if (get_pat_info(vma, &paddr, &pgprot))
return -EINVAL;
- }
- pgprot = __pgprot(prot);
+ /* reserve the whole chunk covered by vma. */
return reserve_pfn_range(paddr, vma_size, &pgprot, 1);
}
@@ -1045,7 +1070,6 @@ void untrack_pfn(struct vm_area_struct *
unsigned long size, bool mm_wr_locked)
{
resource_size_t paddr;
- unsigned long prot;
if (vma && !(vma->vm_flags & VM_PAT))
return;
@@ -1053,11 +1077,8 @@ void untrack_pfn(struct vm_area_struct *
/* free the chunk starting from pfn or the whole chunk */
paddr = (resource_size_t)pfn << PAGE_SHIFT;
if (!paddr && !size) {
- if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) {
- WARN_ON_ONCE(1);
+ if (get_pat_info(vma, &paddr, NULL))
return;
- }
-
size = vma->vm_end - vma->vm_start;
}
free_pfn_range(paddr, size);
--- a/mm/memory.c~x86-mm-pat-fix-vm_pat-handling-in-cow-mappings
+++ a/mm/memory.c
@@ -5973,6 +5973,10 @@ int follow_phys(struct vm_area_struct *v
goto out;
pte = ptep_get(ptep);
+ /* Never return PFNs of anon folios in COW mappings. */
+ if (vm_normal_folio(vma, address, pte))
+ goto unlock;
+
if ((flags & FOLL_WRITE) && !pte_write(pte))
goto unlock;
_
Patches currently in -mm which might be from david(a)redhat.com are
mm-madvise-make-madv_populate_readwrite-handle-vm_fault_retry-properly.patch
mm-madvise-dont-perform-madvise-vma-walk-for-madv_populate_readwrite.patch
mm-userfaultfd-dont-place-zeropages-when-zeropages-are-disallowed.patch
s390-mm-re-enable-the-shared-zeropage-for-pv-and-skeys-kvm-guests.patch
mm-convert-folio_estimated_sharers-to-folio_likely_mapped_shared.patch
mm-convert-folio_estimated_sharers-to-folio_likely_mapped_shared-fix.patch
selftests-memfd_secret-add-vmsplice-test.patch
mm-merge-folio_is_secretmem-and-folio_fast_pin_allowed-into-gup_fast_folio_allowed.patch
mm-optimize-config_per_vma_lock-member-placement-in-vm_area_struct.patch
mm-remove-prot-parameter-from-move_pte.patch
mm-gup-consistently-name-gup-fast-functions.patch
mm-treewide-rename-config_have_fast_gup-to-config_have_gup_fast.patch
mm-use-gup-fast-instead-fast-gup-in-remaining-comments.patch
The quilt patch titled
Subject: selftests/mm: include strings.h for ffsl
has been removed from the -mm tree. Its filename was
selftests-mm-include-stringsh-for-ffsl.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Edward Liaw <edliaw(a)google.com>
Subject: selftests/mm: include strings.h for ffsl
Date: Fri, 29 Mar 2024 18:58:10 +0000
Got a compilation error on Android for ffsl after 91b80cc5b39f
("selftests: mm: fix map_hugetlb failure on 64K page size systems")
included vm_util.h.
Link: https://lkml.kernel.org/r/20240329185814.16304-1-edliaw@google.com
Fixes: af605d26a8f2 ("selftests/mm: merge util.h into vm_util.h")
Signed-off-by: Edward Liaw <edliaw(a)google.com>
Reviewed-by: Muhammad Usama Anjum <usama.anjum(a)collabora.com>
Cc: Axel Rasmussen <axelrasmussen(a)google.com>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: "Mike Rapoport (IBM)" <rppt(a)kernel.org>
Cc: Peter Xu <peterx(a)redhat.com>
Cc: Shuah Khan <shuah(a)kernel.org>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
tools/testing/selftests/mm/vm_util.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/tools/testing/selftests/mm/vm_util.h~selftests-mm-include-stringsh-for-ffsl
+++ a/tools/testing/selftests/mm/vm_util.h
@@ -3,7 +3,7 @@
#include <stdbool.h>
#include <sys/mman.h>
#include <err.h>
-#include <string.h> /* ffsl() */
+#include <strings.h> /* ffsl() */
#include <unistd.h> /* _SC_PAGESIZE */
#define BIT_ULL(nr) (1ULL << (nr))
_
Patches currently in -mm which might be from edliaw(a)google.com are
The quilt patch titled
Subject: mm/secretmem: fix GUP-fast succeeding on secretmem folios
has been removed from the -mm tree. Its filename was
mm-secretmem-fix-gup-fast-succeeding-on-secretmem-folios.patch
This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: David Hildenbrand <david(a)redhat.com>
Subject: mm/secretmem: fix GUP-fast succeeding on secretmem folios
Date: Tue, 26 Mar 2024 15:32:08 +0100
folio_is_secretmem() currently relies on secretmem folios being LRU
folios, to save some cycles.
However, folios might reside in a folio batch without the LRU flag set, or
temporarily have their LRU flag cleared. Consequently, the LRU flag is
unreliable for this purpose.
In particular, this is the case when secretmem_fault() allocates a fresh
page and calls filemap_add_folio()->folio_add_lru(). The folio might be
added to the per-cpu folio batch and won't get the LRU flag set until the
batch was drained using e.g., lru_add_drain().
Consequently, folio_is_secretmem() might not detect secretmem folios and
GUP-fast can succeed in grabbing a secretmem folio, crashing the kernel
when we would later try reading/writing to the folio, because the folio
has been unmapped from the directmap.
Fix it by removing that unreliable check.
Link: https://lkml.kernel.org/r/20240326143210.291116-2-david@redhat.com
Fixes: 1507f51255c9 ("mm: introduce memfd_secret system call to create "secret" memory areas")
Signed-off-by: David Hildenbrand <david(a)redhat.com>
Reported-by: xingwei lee <xrivendell7(a)gmail.com>
Reported-by: yue sun <samsun1006219(a)gmail.com>
Closes: https://lore.kernel.org/lkml/CABOYnLyevJeravW=QrH0JUPYEcDN160aZFb7kwndm-J2r…
Debugged-by: Miklos Szeredi <miklos(a)szeredi.hu>
Tested-by: Miklos Szeredi <mszeredi(a)redhat.com>
Reviewed-by: Mike Rapoport (IBM) <rppt(a)kernel.org>
Cc: Lorenzo Stoakes <lstoakes(a)gmail.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
include/linux/secretmem.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/include/linux/secretmem.h~mm-secretmem-fix-gup-fast-succeeding-on-secretmem-folios
+++ a/include/linux/secretmem.h
@@ -13,10 +13,10 @@ static inline bool folio_is_secretmem(st
/*
* Using folio_mapping() is quite slow because of the actual call
* instruction.
- * We know that secretmem pages are not compound and LRU so we can
+ * We know that secretmem pages are not compound, so we can
* save a couple of cycles here.
*/
- if (folio_test_large(folio) || !folio_test_lru(folio))
+ if (folio_test_large(folio))
return false;
mapping = (struct address_space *)
_
Patches currently in -mm which might be from david(a)redhat.com are
mm-madvise-make-madv_populate_readwrite-handle-vm_fault_retry-properly.patch
mm-madvise-dont-perform-madvise-vma-walk-for-madv_populate_readwrite.patch
mm-userfaultfd-dont-place-zeropages-when-zeropages-are-disallowed.patch
s390-mm-re-enable-the-shared-zeropage-for-pv-and-skeys-kvm-guests.patch
mm-convert-folio_estimated_sharers-to-folio_likely_mapped_shared.patch
mm-convert-folio_estimated_sharers-to-folio_likely_mapped_shared-fix.patch
selftests-memfd_secret-add-vmsplice-test.patch
mm-merge-folio_is_secretmem-and-folio_fast_pin_allowed-into-gup_fast_folio_allowed.patch
mm-optimize-config_per_vma_lock-member-placement-in-vm_area_struct.patch
mm-remove-prot-parameter-from-move_pte.patch
mm-gup-consistently-name-gup-fast-functions.patch
mm-treewide-rename-config_have_fast_gup-to-config_have_gup_fast.patch
mm-use-gup-fast-instead-fast-gup-in-remaining-comments.patch
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 7a1b3490f47e88ec4cbde65f1a77a0f4bc972282
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040524-stitch-resolute-ead5@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7a1b3490f47e88ec4cbde65f1a77a0f4bc972282 Mon Sep 17 00:00:00 2001
From: Davide Caratti <dcaratti(a)redhat.com>
Date: Fri, 29 Mar 2024 13:08:52 +0100
Subject: [PATCH] mptcp: don't account accept() of non-MPC client as fallback
to TCP
Current MPTCP servers increment MPTcpExtMPCapableFallbackACK when they
accept non-MPC connections. As reported by Christoph, this is "surprising"
because the counter might become greater than MPTcpExtMPCapableSYNRX.
MPTcpExtMPCapableFallbackACK counter's name suggests it should only be
incremented when a connection was seen using MPTCP options, then a
fallback to TCP has been done. Let's do that by incrementing it when
the subflow context of an inbound MPC connection attempt is dropped.
Also, update mptcp_connect.sh kselftest, to ensure that the
above MIB does not increment in case a pure TCP client connects to a
MPTCP server.
Fixes: fc518953bc9c ("mptcp: add and use MIB counter infrastructure")
Cc: stable(a)vger.kernel.org
Reported-by: Christoph Paasch <cpaasch(a)apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/449
Signed-off-by: Davide Caratti <dcaratti(a)redhat.com>
Reviewed-by: Mat Martineau <martineau(a)kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Link: https://lore.kernel.org/r/20240329-upstream-net-20240329-fallback-mib-v1-1-…
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 3a1967bc7bad..7e74b812e366 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -3937,8 +3937,6 @@ static int mptcp_stream_accept(struct socket *sock, struct socket *newsock,
mptcp_set_state(newsk, TCP_CLOSE);
}
} else {
- MPTCP_INC_STATS(sock_net(ssk),
- MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK);
tcpfallback:
newsk->sk_kern_sock = kern;
lock_sock(newsk);
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index 1626dd20c68f..6042a47da61b 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -905,6 +905,8 @@ static struct sock *subflow_syn_recv_sock(const struct sock *sk,
return child;
fallback:
+ if (fallback)
+ SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK);
mptcp_subflow_drop_ctx(child);
return child;
}
diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.sh b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
index 4c4248554826..4131f3263a48 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_connect.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
@@ -383,12 +383,14 @@ do_transfer()
local stat_cookierx_last
local stat_csum_err_s
local stat_csum_err_c
+ local stat_tcpfb_last_l
stat_synrx_last_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableSYNRX")
stat_ackrx_last_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableACKRX")
stat_cookietx_last=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesSent")
stat_cookierx_last=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesRecv")
stat_csum_err_s=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtDataCsumErr")
stat_csum_err_c=$(mptcp_lib_get_counter "${connector_ns}" "MPTcpExtDataCsumErr")
+ stat_tcpfb_last_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableFallbackACK")
timeout ${timeout_test} \
ip netns exec ${listener_ns} \
@@ -457,11 +459,13 @@ do_transfer()
local stat_cookietx_now
local stat_cookierx_now
local stat_ooo_now
+ local stat_tcpfb_now_l
stat_synrx_now_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableSYNRX")
stat_ackrx_now_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableACKRX")
stat_cookietx_now=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesSent")
stat_cookierx_now=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesRecv")
stat_ooo_now=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtTCPOFOQueue")
+ stat_tcpfb_now_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableFallbackACK")
expect_synrx=$((stat_synrx_last_l))
expect_ackrx=$((stat_ackrx_last_l))
@@ -508,6 +512,11 @@ do_transfer()
fi
fi
+ if [ ${stat_ooo_now} -eq 0 ] && [ ${stat_tcpfb_last_l} -ne ${stat_tcpfb_now_l} ]; then
+ mptcp_lib_pr_fail "unexpected fallback to TCP"
+ rets=1
+ fi
+
if [ $cookies -eq 2 ];then
if [ $stat_cookietx_last -ge $stat_cookietx_now ] ;then
extra+=" WARN: CookieSent: did not advance"
The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 7a1b3490f47e88ec4cbde65f1a77a0f4bc972282
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2024040523-handling-conceded-2895@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7a1b3490f47e88ec4cbde65f1a77a0f4bc972282 Mon Sep 17 00:00:00 2001
From: Davide Caratti <dcaratti(a)redhat.com>
Date: Fri, 29 Mar 2024 13:08:52 +0100
Subject: [PATCH] mptcp: don't account accept() of non-MPC client as fallback
to TCP
Current MPTCP servers increment MPTcpExtMPCapableFallbackACK when they
accept non-MPC connections. As reported by Christoph, this is "surprising"
because the counter might become greater than MPTcpExtMPCapableSYNRX.
MPTcpExtMPCapableFallbackACK counter's name suggests it should only be
incremented when a connection was seen using MPTCP options, then a
fallback to TCP has been done. Let's do that by incrementing it when
the subflow context of an inbound MPC connection attempt is dropped.
Also, update mptcp_connect.sh kselftest, to ensure that the
above MIB does not increment in case a pure TCP client connects to a
MPTCP server.
Fixes: fc518953bc9c ("mptcp: add and use MIB counter infrastructure")
Cc: stable(a)vger.kernel.org
Reported-by: Christoph Paasch <cpaasch(a)apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/449
Signed-off-by: Davide Caratti <dcaratti(a)redhat.com>
Reviewed-by: Mat Martineau <martineau(a)kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Link: https://lore.kernel.org/r/20240329-upstream-net-20240329-fallback-mib-v1-1-…
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 3a1967bc7bad..7e74b812e366 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -3937,8 +3937,6 @@ static int mptcp_stream_accept(struct socket *sock, struct socket *newsock,
mptcp_set_state(newsk, TCP_CLOSE);
}
} else {
- MPTCP_INC_STATS(sock_net(ssk),
- MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK);
tcpfallback:
newsk->sk_kern_sock = kern;
lock_sock(newsk);
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index 1626dd20c68f..6042a47da61b 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -905,6 +905,8 @@ static struct sock *subflow_syn_recv_sock(const struct sock *sk,
return child;
fallback:
+ if (fallback)
+ SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK);
mptcp_subflow_drop_ctx(child);
return child;
}
diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.sh b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
index 4c4248554826..4131f3263a48 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_connect.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
@@ -383,12 +383,14 @@ do_transfer()
local stat_cookierx_last
local stat_csum_err_s
local stat_csum_err_c
+ local stat_tcpfb_last_l
stat_synrx_last_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableSYNRX")
stat_ackrx_last_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableACKRX")
stat_cookietx_last=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesSent")
stat_cookierx_last=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesRecv")
stat_csum_err_s=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtDataCsumErr")
stat_csum_err_c=$(mptcp_lib_get_counter "${connector_ns}" "MPTcpExtDataCsumErr")
+ stat_tcpfb_last_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableFallbackACK")
timeout ${timeout_test} \
ip netns exec ${listener_ns} \
@@ -457,11 +459,13 @@ do_transfer()
local stat_cookietx_now
local stat_cookierx_now
local stat_ooo_now
+ local stat_tcpfb_now_l
stat_synrx_now_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableSYNRX")
stat_ackrx_now_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableACKRX")
stat_cookietx_now=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesSent")
stat_cookierx_now=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtSyncookiesRecv")
stat_ooo_now=$(mptcp_lib_get_counter "${listener_ns}" "TcpExtTCPOFOQueue")
+ stat_tcpfb_now_l=$(mptcp_lib_get_counter "${listener_ns}" "MPTcpExtMPCapableFallbackACK")
expect_synrx=$((stat_synrx_last_l))
expect_ackrx=$((stat_ackrx_last_l))
@@ -508,6 +512,11 @@ do_transfer()
fi
fi
+ if [ ${stat_ooo_now} -eq 0 ] && [ ${stat_tcpfb_last_l} -ne ${stat_tcpfb_now_l} ]; then
+ mptcp_lib_pr_fail "unexpected fallback to TCP"
+ rets=1
+ fi
+
if [ $cookies -eq 2 ];then
if [ $stat_cookietx_last -ge $stat_cookietx_now ] ;then
extra+=" WARN: CookieSent: did not advance"