In the Linux kernel, the following vulnerability has been resolved:
hugetlbfs: fix null-ptr-deref in hugetlbfs_parse_param()
Syzkaller reports a null-ptr-deref bug as follows:
======================================================
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:hugetlbfs_parse_param+0x1dd/0x8e0 fs/hugetlbfs/inode.c:1380
[...]
Call Trace:
<TASK>
vfs_parse_fs_param fs/fs_context.c:148 [inline]
vfs_parse_fs_param+0x1f9/0x3c0 fs/fs_context.c:129
vfs_parse_fs_string+0xdb/0x170 fs/fs_context.c:191
generic_parse_monolithic+0x16f/0x1f0 fs/fs_context.c:231
do_new_mount fs/namespace.c:3036 [inline]
path_mount+0x12de/0x1e20 fs/namespace.c:3370
do_mount fs/namespace.c:3383 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount fs/namespace.c:3568 [inline]
__x64_sys_mount+0x27f/0x300 fs/namespace.c:3568
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
[...]
</TASK>
======================================================
According to commit "vfs: parse: deal with zero length string value",
kernel will set the param->string to null pointer in vfs_parse_fs_string()
if fs string has zero length.
Yet the problem is that, hugetlbfs_parse_param() will dereference the
param->string, without checking whether it is a null pointer. To be more
specific, if hugetlbfs_parse_param() parses an illegal mount parameter,
such as "size=,", kernel will constructs struct fs_parameter with null
pointer in vfs_parse_fs_string(), then passes this struct fs_parameter to
hugetlbfs_parse_param(), which triggers the above null-ptr-deref bug.
This patch solves it by adding sanity check on param->string
in hugetlbfs_parse_param().
In the Linux kernel, the following vulnerability has been resolved:
ACPI: processor: idle: Check acpi_fetch_acpi_dev() return value
The return value of acpi_fetch_acpi_dev() could be NULL, which would
cause a NULL pointer dereference to occur in acpi_device_hid().
[ rjw: Subject and changelog edits, added empty line after if () ]
In the Linux kernel, the following vulnerability has been resolved:
jbd2: fix potential use-after-free in jbd2_fc_wait_bufs
In 'jbd2_fc_wait_bufs' use 'bh' after put buffer head reference count
which may lead to use-after-free.
So judge buffer if uptodate before put buffer head reference count.
In the Linux kernel, the following vulnerability has been resolved:
nbd: Fix hung when signal interrupts nbd_start_device_ioctl()
syzbot reported hung task [1]. The following program is a simplified
version of the reproducer:
int main(void)
{
int sv[2], fd;
if (socketpair(AF_UNIX, SOCK_STREAM, 0, sv) < 0)
return 1;
if ((fd = open("/dev/nbd0", 0)) < 0)
return 1;
if (ioctl(fd, NBD_SET_SIZE_BLOCKS, 0x81) < 0)
return 1;
if (ioctl(fd, NBD_SET_SOCK, sv[0]) < 0)
return 1;
if (ioctl(fd, NBD_DO_IT) < 0)
return 1;
return 0;
}
When signal interrupt nbd_start_device_ioctl() waiting the condition
atomic_read(&config->recv_threads) == 0, the task can hung because it
waits the completion of the inflight IOs.
This patch fixes the issue by clearing queue, not just shutdown, when
signal interrupt nbd_start_device_ioctl().
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix potential out of bound read in ext4_fc_replay_scan()
For scan loop must ensure that at least EXT4_FC_TAG_BASE_LEN space. If remain
space less than EXT4_FC_TAG_BASE_LEN which will lead to out of bound read
when mounting corrupt file system image.
ADD_RANGE/HEAD/TAIL is needed to add extra check when do journal scan, as this
three tags will read data during scan, tag length couldn't less than data length
which will read.
In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: Fix double release compute pasid
If kfd_process_device_init_vm returns failure after vm is converted to
compute vm and vm->pasid set to compute pasid, KFD will not take
pdd->drm_file reference. As a result, drm close file handler maybe
called to release the compute pasid before KFD process destroy worker to
release the same pasid and set vm->pasid to zero, this generates below
WARNING backtrace and NULL pointer access.
Add helper amdgpu_amdkfd_gpuvm_set_vm_pasid and call it at the last step
of kfd_process_device_init_vm, to ensure vm pasid is the original pasid
if acquiring vm failed or is the compute pasid with pdd->drm_file
reference taken to avoid double release same pasid.
amdgpu: Failed to create process VM object
ida_free called for id=32770 which is not allocated.
WARNING: CPU: 57 PID: 72542 at ../lib/idr.c:522 ida_free+0x96/0x140
RIP: 0010:ida_free+0x96/0x140
Call Trace:
amdgpu_pasid_free_delayed+0xe1/0x2a0 [amdgpu]
amdgpu_driver_postclose_kms+0x2d8/0x340 [amdgpu]
drm_file_free.part.13+0x216/0x270 [drm]
drm_close_helper.isra.14+0x60/0x70 [drm]
drm_release+0x6e/0xf0 [drm]
__fput+0xcc/0x280
____fput+0xe/0x20
task_work_run+0x96/0xc0
do_exit+0x3d0/0xc10
BUG: kernel NULL pointer dereference, address: 0000000000000000
RIP: 0010:ida_free+0x76/0x140
Call Trace:
amdgpu_pasid_free_delayed+0xe1/0x2a0 [amdgpu]
amdgpu_driver_postclose_kms+0x2d8/0x340 [amdgpu]
drm_file_free.part.13+0x216/0x270 [drm]
drm_close_helper.isra.14+0x60/0x70 [drm]
drm_release+0x6e/0xf0 [drm]
__fput+0xcc/0x280
____fput+0xe/0x20
task_work_run+0x96/0xc0
do_exit+0x3d0/0xc10
In the Linux kernel, the following vulnerability has been resolved:
qlcnic: prevent ->dcb use-after-free on qlcnic_dcb_enable() failure
adapter->dcb would get silently freed inside qlcnic_dcb_enable() in
case qlcnic_dcb_attach() would return an error, which always happens
under OOM conditions. This would lead to use-after-free because both
of the existing callers invoke qlcnic_dcb_get_info() on the obtained
pointer, which is potentially freed at that point.
Propagate errors from qlcnic_dcb_enable(), and instead free the dcb
pointer at callsite using qlcnic_dcb_free(). This also removes the now
unused qlcnic_clear_dcb_ops() helper, which was a simple wrapper around
kfree() also causing memory leaks for partially initialized dcb.
Found by Linux Verification Center (linuxtesting.org) with the SVACE
static analysis tool.
In the Linux kernel, the following vulnerability has been resolved:
btrfs: do not BUG_ON() on ENOMEM when dropping extent items for a range
If we get -ENOMEM while dropping file extent items in a given range, at
btrfs_drop_extents(), due to failure to allocate memory when attempting to
increment the reference count for an extent or drop the reference count,
we handle it with a BUG_ON(). This is excessive, instead we can simply
abort the transaction and return the error to the caller. In fact most
callers of btrfs_drop_extents(), directly or indirectly, already abort
the transaction if btrfs_drop_extents() returns any error.
Also, we already have error paths at btrfs_drop_extents() that may return
-ENOMEM and in those cases we abort the transaction, like for example
anything that changes the b+tree may return -ENOMEM due to a failure to
allocate a new extent buffer when COWing an existing extent buffer, such
as a call to btrfs_duplicate_item() for example.
So replace the BUG_ON() calls with proper logic to abort the transaction
and return the error.