In the Linux kernel, the following vulnerability has been resolved:
net: batman-adv: fix error handling
Syzbot reported ODEBUG warning in batadv_nc_mesh_free(). The problem was
in wrong error handling in batadv_mesh_init().
Before this patch batadv_mesh_init() was calling batadv_mesh_free() in case
of any batadv_*_init() calls failure. This approach may work well, when
there is some kind of indicator, which can tell which parts of batadv are
initialized; but there isn't any.
All written above lead to cleaning up uninitialized fields. Even if we hide
ODEBUG warning by initializing bat_priv->nc.work, syzbot was able to hit
GPF in batadv_nc_purge_paths(), because hash pointer in still NULL. [1]
To fix these bugs we can unwind batadv_*_init() calls one by one.
It is good approach for 2 reasons: 1) It fixes bugs on error handling
path 2) It improves the performance, since we won't call unneeded
batadv_*_free() functions.
So, this patch makes all batadv_*_init() clean up all allocated memory
before returning with an error to no call correspoing batadv_*_free()
and open-codes batadv_mesh_free() with proper order to avoid touching
uninitialized fields.
In the Linux kernel, the following vulnerability has been resolved:
IB/qib: Protect from buffer overflow in struct qib_user_sdma_pkt fields
Overflowing either addrlimit or bytes_togo can allow userspace to trigger
a buffer overflow of kernel memory. Check for overflows in all the places
doing math on user controlled buffers.
In the Linux kernel, the following vulnerability has been resolved:
drm/ttm: fix memleak in ttm_transfered_destroy
We need to cleanup the fences for ghost objects as well.
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=214029
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=214447
In the Linux kernel, the following vulnerability has been resolved:
comedi: vmk80xx: fix bulk-buffer overflow
The driver is using endpoint-sized buffers but must not assume that the
tx and rx buffers are of equal size or a malicious device could overflow
the slab-allocated receive buffer when doing bulk transfers.
In the Linux kernel, the following vulnerability has been resolved:
comedi: vmk80xx: fix transfer-buffer overflows
The driver uses endpoint-sized USB transfer buffers but up until
recently had no sanity checks on the sizes.
Commit e1f13c879a7c ("staging: comedi: check validity of wMaxPacketSize
of usb endpoints found") inadvertently fixed NULL-pointer dereferences
when accessing the transfer buffers in case a malicious device has a
zero wMaxPacketSize.
Make sure to allocate buffers large enough to handle also the other
accesses that are done without a size check (e.g. byte 18 in
vmk80xx_cnt_insn_read() for the VMK8061_MODEL) to avoid writing beyond
the buffers, for example, when doing descriptor fuzzing.
The original driver was for a low-speed device with 8-byte buffers.
Support was later added for a device that uses bulk transfers and is
presumably a full-speed device with a maximum 64-byte wMaxPacketSize.
In the Linux kernel, the following vulnerability has been resolved:
comedi: dt9812: fix DMA buffers on stack
USB transfer buffers are typically mapped for DMA and must not be
allocated on the stack or transfers will fail.
Allocate proper transfer buffers in the various command helpers and
return an error on short transfers instead of acting on random stack
data.
Note that this also fixes a stack info leak on systems where DMA is not
used as 32 bytes are always sent to the device regardless of how short
the command is.
In the Linux kernel, the following vulnerability has been resolved:
isofs: Fix out of bound access for corrupted isofs image
When isofs image is suitably corrupted isofs_read_inode() can read data
beyond the end of buffer. Sanity-check the directory entry length before
using it.
In the Linux kernel, the following vulnerability has been resolved:
scsi: core: Put LLD module refcnt after SCSI device is released
SCSI host release is triggered when SCSI device is freed. We have to make
sure that the low-level device driver module won't be unloaded before SCSI
host instance is released because shost->hostt is required in the release
handler.
Make sure to put LLD module refcnt after SCSI device is released.
Fixes a kernel panic of 'BUG: unable to handle page fault for address'
reported by Changhui and Yi.
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: mount fails with buffer overflow in strlen
Starting with kernel 5.11 built with CONFIG_FORTIFY_SOURCE mouting an
ocfs2 filesystem with either o2cb or pcmk cluster stack fails with the
trace below. Problem seems to be that strings for cluster stack and
cluster name are not guaranteed to be null terminated in the disk
representation, while strlcpy assumes that the source string is always
null terminated. This causes a read outside of the source string
triggering the buffer overflow detection.
detected buffer overflow in strlen
------------[ cut here ]------------
kernel BUG at lib/string.c:1149!
invalid opcode: 0000 [#1] SMP PTI
CPU: 1 PID: 910 Comm: mount.ocfs2 Not tainted 5.14.0-1-amd64 #1
Debian 5.14.6-2
RIP: 0010:fortify_panic+0xf/0x11
...
Call Trace:
ocfs2_initialize_super.isra.0.cold+0xc/0x18 [ocfs2]
ocfs2_fill_super+0x359/0x19b0 [ocfs2]
mount_bdev+0x185/0x1b0
legacy_get_tree+0x27/0x40
vfs_get_tree+0x25/0xb0
path_mount+0x454/0xa20
__x64_sys_mount+0x103/0x140
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae