In the Linux kernel, the following vulnerability has been resolved:
misc/libmasm/module: Fix two use after free in ibmasm_init_one
In ibmasm_init_one, it calls ibmasm_init_remote_input_dev().
Inside ibmasm_init_remote_input_dev, mouse_dev and keybd_dev are
allocated by input_allocate_device(), and assigned to
sp->remote.mouse_dev and sp->remote.keybd_dev respectively.
In the err_free_devices error branch of ibmasm_init_one,
mouse_dev and keybd_dev are freed by input_free_device(), and return
error. Then the execution runs into error_send_message error branch
of ibmasm_init_one, where ibmasm_free_remote_input_dev(sp) is called
to unregister the freed sp->remote.mouse_dev and sp->remote.keybd_dev.
My patch add a "error_init_remote" label to handle the error of
ibmasm_init_remote_input_dev(), to avoid the uaf bugs.
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid racing on fsync_entry_slab by multi filesystem instances
As syzbot reported, there is an use-after-free issue during f2fs recovery:
Use-after-free write at 0xffff88823bc16040 (in kfence-#10):
kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
mount_bdev+0x26c/0x3a0 fs/super.c:1367
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1497
do_new_mount fs/namespace.c:2905 [inline]
path_mount+0x196f/0x2be0 fs/namespace.c:3235
do_mount fs/namespace.c:3248 [inline]
__do_sys_mount fs/namespace.c:3456 [inline]
__se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0x44/0xae
The root cause is multi f2fs filesystem instances can race on accessing
global fsync_entry_slab pointer, result in use-after-free issue of slab
cache, fixes to init/destroy this slab cache only once during module
init/destroy procedure to avoid this issue.
In the Linux kernel, the following vulnerability has been resolved:
smackfs: restrict bytes count in smk_set_cipso()
Oops, I failed to update subject line.
From 07571157c91b98ce1a4aa70967531e64b78e8346 Mon Sep 17 00:00:00 2001
Date: Mon, 12 Apr 2021 22:25:06 +0900
Subject: [PATCH] smackfs: restrict bytes count in smk_set_cipso()
Commit 7ef4c19d245f3dc2 ("smackfs: restrict bytes count in smackfs write
functions") missed that count > SMK_CIPSOMAX check applies to only
format == SMK_FIXED24_FMT case.
In the Linux kernel, the following vulnerability has been resolved:
media: v4l2-core: explicitly clear ioctl input data
As seen from a recent syzbot bug report, mistakes in the compat ioctl
implementation can lead to uninitialized kernel stack data getting used
as input for driver ioctl handlers.
The reported bug is now fixed, but it's possible that other related
bugs are still present or get added in the future. As the drivers need
to check user input already, the possible impact is fairly low, but it
might still cause an information leak.
To be on the safe side, always clear the entire ioctl buffer before
calling the conversion handler functions that are meant to initialize
them.
In the Linux kernel, the following vulnerability has been resolved:
jfs: fix GPF in diFree
Avoid passing inode with
JFS_SBI(inode->i_sb)->ipimap == NULL to
diFree()[1]. GFP will appear:
struct inode *ipimap = JFS_SBI(ip->i_sb)->ipimap;
struct inomap *imap = JFS_IP(ipimap)->i_imap;
JFS_IP() will return invalid pointer when ipimap == NULL
Call Trace:
diFree+0x13d/0x2dc0 fs/jfs/jfs_imap.c:853 [1]
jfs_evict_inode+0x2c9/0x370 fs/jfs/inode.c:154
evict+0x2ed/0x750 fs/inode.c:578
iput_final fs/inode.c:1654 [inline]
iput.part.0+0x3fe/0x820 fs/inode.c:1680
iput+0x58/0x70 fs/inode.c:1670
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix possible UAF when remounting r/o a mmp-protected file system
After commit 618f003199c6 ("ext4: fix memory leak in
ext4_fill_super"), after the file system is remounted read-only, there
is a race where the kmmpd thread can exit, causing sbi->s_mmp_tsk to
point at freed memory, which the call to ext4_stop_mmpd() can trip
over.
Fix this by only allowing kmmpd() to exit when it is stopped via
ext4_stop_mmpd().
Bug-Report-Link: <20210629143603.2166962-1-yebin10@huawei.com>
In the Linux kernel, the following vulnerability has been resolved:
dm btree remove: assign new_root only when removal succeeds
remove_raw() in dm_btree_remove() may fail due to IO read error
(e.g. read the content of origin block fails during shadowing),
and the value of shadow_spine::root is uninitialized, but
the uninitialized value is still assign to new_root in the
end of dm_btree_remove().
For dm-thin, the value of pmd->details_root or pmd->root will become
an uninitialized value, so if trying to read details_info tree again
out-of-bound memory may occur as showed below:
general protection fault, probably for non-canonical address 0x3fdcb14c8d7520
CPU: 4 PID: 515 Comm: dmsetup Not tainted 5.13.0-rc6
Hardware name: QEMU Standard PC
RIP: 0010:metadata_ll_load_ie+0x14/0x30
Call Trace:
sm_metadata_count_is_more_than_one+0xb9/0xe0
dm_tm_shadow_block+0x52/0x1c0
shadow_step+0x59/0xf0
remove_raw+0xb2/0x170
dm_btree_remove+0xf4/0x1c0
dm_pool_delete_thin_device+0xc3/0x140
pool_message+0x218/0x2b0
target_message+0x251/0x290
ctl_ioctl+0x1c4/0x4d0
dm_ctl_ioctl+0xe/0x20
__x64_sys_ioctl+0x7b/0xb0
do_syscall_64+0x40/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xae
Fixing it by only assign new_root when removal succeeds
In the Linux kernel, the following vulnerability has been resolved:
virtio-blk: Fix memory leak among suspend/resume procedure
The vblk->vqs should be freed before we call init_vqs()
in virtblk_restore().
In the Linux kernel, the following vulnerability has been resolved:
watchdog: Fix possible use-after-free by calling del_timer_sync()
This driver's remove path calls del_timer(). However, that function
does not wait until the timer handler finishes. This means that the
timer handler may still be running after the driver's remove function
has finished, which would result in a use-after-free.
Fix by calling del_timer_sync(), which makes sure the timer handler
has finished, and unable to re-schedule itself.
In the Linux kernel, the following vulnerability has been resolved:
watchdog: sc520_wdt: Fix possible use-after-free in wdt_turnoff()
This module's remove path calls del_timer(). However, that function
does not wait until the timer handler finishes. This means that the
timer handler may still be running after the driver's remove function
has finished, which would result in a use-after-free.
Fix by calling del_timer_sync(), which makes sure the timer handler
has finished, and unable to re-schedule itself.