The VMA count limit check in do_mmap() and do_brk_flags() uses a
strict inequality (>), which allows a process's VMA count to exceed
the configured sysctl_max_map_count limit by one.
A process with mm->map_count == sysctl_max_map_count will incorrectly
pass this check and then exceed the limit upon allocation of a new VMA
when its map_count is incremented.
Other VMA allocation paths, such as split_vma(), already use the
correct, inclusive (>=) comparison.
Fix this bug by changing the comparison to be inclusive in do_mmap()
and do_brk_flags(), bringing them in line with the correct behavior
of other allocation paths.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: <stable(a)vger.kernel.org>
Cc: Andrew Morton <akpm(a)linux-foundation.org>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: "Liam R. Howlett" <Liam.Howlett(a)oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Cc: Mike Rapoport <rppt(a)kernel.org>
Cc: Minchan Kim <minchan(a)kernel.org>
Cc: Pedro Falcato <pfalcato(a)suse.de>
Signed-off-by: Kalesh Singh <kaleshsingh(a)google.com>
---
Chnages in v2:
- Fix mmap check, per Pedro
mm/mmap.c | 2 +-
mm/vma.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/mm/mmap.c b/mm/mmap.c
index 7306253cc3b5..e5370e7fcd8f 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -374,7 +374,7 @@ unsigned long do_mmap(struct file *file, unsigned long addr,
return -EOVERFLOW;
/* Too many mappings? */
- if (mm->map_count > sysctl_max_map_count)
+ if (mm->map_count >= sysctl_max_map_count)
return -ENOMEM;
/*
diff --git a/mm/vma.c b/mm/vma.c
index 3b12c7579831..033a388bc4b1 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -2772,7 +2772,7 @@ int do_brk_flags(struct vma_iterator *vmi, struct vm_area_struct *vma,
if (!may_expand_vm(mm, vm_flags, len >> PAGE_SHIFT))
return -ENOMEM;
- if (mm->map_count > sysctl_max_map_count)
+ if (mm->map_count >= sysctl_max_map_count)
return -ENOMEM;
if (security_vm_enough_memory_mm(mm, len >> PAGE_SHIFT))
--
2.51.0.384.g4c02a37b29-goog
Fix a memory leak in netpoll and introduce netconsole selftests that
expose the issue when running with kmemleak detection enabled.
This patchset includes a selftest for netpoll with multiple concurrent
users (netconsole + bonding), which simulates the scenario from test[1]
that originally demonstrated the issue allegedly fixed by commit
efa95b01da18 ("netpoll: fix use after free") - a commit that is now
being reverted.
Sending this to "net" branch because this is a fix, and the selftest
might help with the backports validation.
Link: https://lore.kernel.org/lkml/96b940137a50e5c387687bb4f57de8b0435a653f.14048… [1]
Signed-off-by: Breno Leitao <leitao(a)debian.org>
---
Changes in v5:
- Set CONFIG_BONDING=m in selftests/drivers/net/config.
- Link to v4: https://lore.kernel.org/r/20250917-netconsole_torture-v4-0-0a5b3b8f81ce@deb…
Changes in v4:
- Added an additional selftest to test multiple netpoll users in
parallel
- Link to v3: https://lore.kernel.org/r/20250905-netconsole_torture-v3-0-875c7febd316@deb…
Changes in v3:
- This patchset is a merge of the fix and the selftest together as
recommended by Jakub.
Changes in v2:
- Reuse the netconsole creation from lib_netcons.sh. Thus, refactoring
the create_dynamic_target() (Jakub)
- Move the "wait" to after all the messages has been sent.
- Link to v1: https://lore.kernel.org/r/20250902-netconsole_torture-v1-1-03c6066598e9@deb…
---
Breno Leitao (4):
net: netpoll: fix incorrect refcount handling causing incorrect cleanup
selftest: netcons: refactor target creation
selftest: netcons: create a torture test
selftest: netcons: add test for netconsole over bonded interfaces
net/core/netpoll.c | 7 +-
tools/testing/selftests/drivers/net/Makefile | 2 +
tools/testing/selftests/drivers/net/config | 1 +
.../selftests/drivers/net/lib/sh/lib_netcons.sh | 197 ++++++++++++++++++---
.../selftests/drivers/net/netcons_over_bonding.sh | 76 ++++++++
.../selftests/drivers/net/netcons_torture.sh | 127 +++++++++++++
6 files changed, 385 insertions(+), 25 deletions(-)
---
base-commit: 5e87fdc37f8dc619549d49ba5c951b369ce7c136
change-id: 20250902-netconsole_torture-8fc23f0aca99
Best regards,
--
Breno Leitao <leitao(a)debian.org>
We were copying the bo content the bos on the list
"xe->pinned.late.kernel_bo_present" twice on suspend.
Presumingly the intent is to copy the pinned external bos on
the first pass.
This is harmless since we (currently) should have no pinned
external bos needing copy since
a) exernal system bos don't have compressed content,
b) We do not (yet) allow pinning of VRAM bos.
Still, fix this up so that we copy pinned external bos on
the first pass. We're about to allow bos pinned in VRAM.
Fixes: c6a4d46ec1d7 ("drm/xe: evict user memory in PM notifier")
Cc: Matthew Auld <matthew.auld(a)intel.com>
Cc: <stable(a)vger.kernel.org> # v6.16+
Signed-off-by: Thomas Hellström <thomas.hellstrom(a)linux.intel.com>
---
drivers/gpu/drm/xe/xe_bo_evict.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_bo_evict.c b/drivers/gpu/drm/xe/xe_bo_evict.c
index 7484ce55a303..d5dbc51e8612 100644
--- a/drivers/gpu/drm/xe/xe_bo_evict.c
+++ b/drivers/gpu/drm/xe/xe_bo_evict.c
@@ -158,8 +158,8 @@ int xe_bo_evict_all(struct xe_device *xe)
if (ret)
return ret;
- ret = xe_bo_apply_to_pinned(xe, &xe->pinned.late.kernel_bo_present,
- &xe->pinned.late.evicted, xe_bo_evict_pinned);
+ ret = xe_bo_apply_to_pinned(xe, &xe->pinned.late.external,
+ &xe->pinned.late.external, xe_bo_evict_pinned);
if (!ret)
ret = xe_bo_apply_to_pinned(xe, &xe->pinned.late.kernel_bo_present,
--
2.51.0