From: Alan Maguire <alan.maguire(a)oracle.com>
commit 7b99f75942da332e3f4f865e55a10fec95a30d4f upstream.
[ small context conflict because of not backported --lang_exclude=rust
option, which is not needed in 5.15 ]
v1.25 of pahole supports filtering out functions with multiple inconsistent
function prototypes or optimized-out parameters from the BTF representation.
These present problems because there is no additional info in BTF saying which
inconsistent prototype matches which function instance to help guide attachment,
and functions with optimized-out parameters can lead to incorrect assumptions
about register contents.
So for now, filter out such functions while adding BTF representations for
functions that have "."-suffixes (foo.isra.0) but not optimized-out parameters.
This patch assumes that below linked changes land in pahole for v1.25.
Issues with pahole filtering being too aggressive in removing functions
appear to be resolved now, but CI and further testing will confirm.
Signed-off-by: Alan Maguire <alan.maguire(a)oracle.com>
Acked-by: Jiri Olsa <jolsa(a)kernel.org>
Link: https://lore.kernel.org/r/20230510130241.1696561-1-alan.maguire@oracle.com
Signed-off-by: Alexei Starovoitov <ast(a)kernel.org>
Signed-off-by: Jiri Olsa <jolsa(a)kernel.org>
---
scripts/pahole-flags.sh | 3 +++
1 file changed, 3 insertions(+)
diff --git a/scripts/pahole-flags.sh b/scripts/pahole-flags.sh
index d38fa6d84d62..5c724f697100 100755
--- a/scripts/pahole-flags.sh
+++ b/scripts/pahole-flags.sh
@@ -20,5 +20,8 @@ fi
if [ "${pahole_ver}" -ge "124" ]; then
extra_paholeopt="${extra_paholeopt} --skip_encoding_btf_enum64"
fi
+if [ "${pahole_ver}" -ge "125" ]; then
+ extra_paholeopt="${extra_paholeopt} --skip_encoding_btf_inconsistent_proto --btf_gen_optimized"
+fi
echo ${extra_paholeopt}
--
2.43.0
commit 9a9ab0d963621d9d12199df9817e66982582d5a5 upstream.
Task A calls binder_update_page_range() to allocate and insert pages on
a remote address space from Task B. For this, Task A pins the remote mm
via mmget_not_zero() first. This can race with Task B do_exit() and the
final mmput() refcount decrement will come from Task A.
Task A | Task B
------------------+------------------
mmget_not_zero() |
| do_exit()
| exit_mm()
| mmput()
mmput() |
exit_mmap() |
remove_vma() |
fput() |
In this case, the work of ____fput() from Task B is queued up in Task A
as TWA_RESUME. So in theory, Task A returns to userspace and the cleanup
work gets executed. However, Task A instead sleep, waiting for a reply
from Task B that never comes (it's dead).
This means the binder_deferred_release() is blocked until an unrelated
binder event forces Task A to go back to userspace. All the associated
death notifications will also be delayed until then.
In order to fix this use mmput_async() that will schedule the work in
the corresponding mm->async_put_work WQ instead of Task A.
Fixes: 457b9a6f09f0 ("Staging: android: add binder driver")
Reviewed-by: Alice Ryhl <aliceryhl(a)google.com>
Signed-off-by: Carlos Llamas <cmllamas(a)google.com>
Link: https://lore.kernel.org/r/20231201172212.1813387-4-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
[cmllamas: fix trivial conflict with missing d8ed45c5dcd4.]
Signed-off-by: Carlos Llamas <cmllamas(a)google.com>
---
drivers/android/binder_alloc.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index 27950f901595..79cac74f0f1a 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -290,7 +290,7 @@ static int binder_update_page_range(struct binder_alloc *alloc, int allocate,
}
if (mm) {
up_read(&mm->mmap_sem);
- mmput(mm);
+ mmput_async(mm);
}
return 0;
@@ -325,7 +325,7 @@ static int binder_update_page_range(struct binder_alloc *alloc, int allocate,
err_no_vma:
if (mm) {
up_read(&mm->mmap_sem);
- mmput(mm);
+ mmput_async(mm);
}
return vma ? -ENOMEM : -ESRCH;
}
base-commit: abc2dd6a248d443c27888aee13cfefd94c3f7407
prerequisite-patch-id: 040c7991c3b5fb63a9d12350a1400c91a057f7d5
--
2.43.0.429.g432eaa2c6b-goog
Hi Greg, Sasha,
Please cherry pick upstream commit 0f35b0a7b8fa ("Revert "drm/amdkfd:
Relocate TBA/TMA to opposite side of VM hole"") to stable kernel 6.6.x
and newer.
This fixes a segfault in mixed graphics and compute workloads.
Thanks,
Alex
Hi Greg and Sasha,
Please consider applying commit bad098d76835 ("rust: Ignore
preserve-most functions") to 6.6.y and 6.7.y (6.1.y does not need it
since `__preserve_most` was introduced in 6.6). It fixes a build error
with Rust + `CONFIG_LIST_HARDENED`. It should apply cleanly.
Thanks!
Cheers,
Miguel
commit 3f489c2067c5824528212b0fc18b28d51332d906 upstream.
The mmap read lock is used during the shrinker's callback, which means
that using alloc->vma pointer isn't safe as it can race with munmap().
As of commit dd2283f2605e ("mm: mmap: zap pages with read mmap_sem in
munmap") the mmap lock is downgraded after the vma has been isolated.
I was able to reproduce this issue by manually adding some delays and
triggering page reclaiming through the shrinker's debug sysfs. The
following KASAN report confirms the UAF:
==================================================================
BUG: KASAN: slab-use-after-free in zap_page_range_single+0x470/0x4b8
Read of size 8 at addr ffff356ed50e50f0 by task bash/478
CPU: 1 PID: 478 Comm: bash Not tainted 6.6.0-rc5-00055-g1c8b86a3799f-dirty #70
Hardware name: linux,dummy-virt (DT)
Call trace:
zap_page_range_single+0x470/0x4b8
binder_alloc_free_page+0x608/0xadc
__list_lru_walk_one+0x130/0x3b0
list_lru_walk_node+0xc4/0x22c
binder_shrink_scan+0x108/0x1dc
shrinker_debugfs_scan_write+0x2b4/0x500
full_proxy_write+0xd4/0x140
vfs_write+0x1ac/0x758
ksys_write+0xf0/0x1dc
__arm64_sys_write+0x6c/0x9c
Allocated by task 492:
kmem_cache_alloc+0x130/0x368
vm_area_alloc+0x2c/0x190
mmap_region+0x258/0x18bc
do_mmap+0x694/0xa60
vm_mmap_pgoff+0x170/0x29c
ksys_mmap_pgoff+0x290/0x3a0
__arm64_sys_mmap+0xcc/0x144
Freed by task 491:
kmem_cache_free+0x17c/0x3c8
vm_area_free_rcu_cb+0x74/0x98
rcu_core+0xa38/0x26d4
rcu_core_si+0x10/0x1c
__do_softirq+0x2fc/0xd24
Last potentially related work creation:
__call_rcu_common.constprop.0+0x6c/0xba0
call_rcu+0x10/0x1c
vm_area_free+0x18/0x24
remove_vma+0xe4/0x118
do_vmi_align_munmap.isra.0+0x718/0xb5c
do_vmi_munmap+0xdc/0x1fc
__vm_munmap+0x10c/0x278
__arm64_sys_munmap+0x58/0x7c
Fix this issue by performing instead a vma_lookup() which will fail to
find the vma that was isolated before the mmap lock downgrade. Note that
this option has better performance than upgrading to a mmap write lock
which would increase contention. Plus, mmap_write_trylock() has been
recently removed anyway.
Fixes: dd2283f2605e ("mm: mmap: zap pages with read mmap_sem in munmap")
Cc: stable(a)vger.kernel.org
Cc: Liam Howlett <liam.howlett(a)oracle.com>
Cc: Minchan Kim <minchan(a)kernel.org>
Reviewed-by: Alice Ryhl <aliceryhl(a)google.com>
Signed-off-by: Carlos Llamas <cmllamas(a)google.com>
Link: https://lore.kernel.org/r/20231201172212.1813387-3-cmllamas@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
[cmllamas: use find_vma() instead of vma_lookup() as commit ce6d42f2e4a2
is missing in v5.10. This only works because we check the vma against
our cached alloc->vma pointer.]
Signed-off-by: Carlos Llamas <cmllamas(a)google.com>
(cherry picked from commit aaa8cde67eba56b3ebe8c2c155e896f9ccaa8bb7)
---
drivers/android/binder_alloc.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index b6bf9caaf1d1..61406bfa454b 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -1002,7 +1002,9 @@ enum lru_status binder_alloc_free_page(struct list_head *item,
goto err_mmget;
if (!mmap_read_trylock(mm))
goto err_mmap_read_lock_failed;
- vma = binder_alloc_get_vma(alloc);
+ vma = find_vma(mm, page_addr);
+ if (vma && vma != binder_alloc_get_vma(alloc))
+ goto err_invalid_vma;
list_lru_isolate(lru, item);
spin_unlock(lock);
@@ -1028,6 +1030,8 @@ enum lru_status binder_alloc_free_page(struct list_head *item,
mutex_unlock(&alloc->mutex);
return LRU_REMOVED_RETRY;
+err_invalid_vma:
+ mmap_read_unlock(mm);
err_mmap_read_lock_failed:
mmput_async(mm);
err_mmget:
--
2.43.0.429.g432eaa2c6b-goog