In the Linux kernel, the following vulnerability has been resolved:
drm/sun4i: dsi: Prevent underflow when computing packet sizes
Currently, the packet overhead is subtracted using unsigned arithmetic.
With a short sync pulse, this could underflow and wrap around to near
the maximal u16 value. Fix this by using signed subtraction. The call to
max() will correctly handle any negative numbers that are produced.
Apply the same fix to the other timings, even though those subtractions
are less likely to underflow.
In the Linux kernel, the following vulnerability has been resolved:
scsi: lpfc: Prevent buffer overflow crashes in debugfs with malformed user input
Malformed user input to debugfs results in buffer overflow crashes. Adapt
input string lengths to fit within internal buffers, leaving space for NULL
terminators.
In the Linux kernel, the following vulnerability has been resolved:
ext4: block range must be validated before use in ext4_mb_clear_bb()
Block range to free is validated in ext4_free_blocks() using
ext4_inode_block_valid() and then it's passed to ext4_mb_clear_bb().
However in some situations on bigalloc file system the range might be
adjusted after the validation in ext4_free_blocks() which can lead to
troubles on corrupted file systems such as one found by syzkaller that
resulted in the following BUG
kernel BUG at fs/ext4/ext4.h:3319!
PREEMPT SMP NOPTI
CPU: 28 PID: 4243 Comm: repro Kdump: loaded Not tainted 5.19.0-rc6+ #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1.fc35 04/01/2014
RIP: 0010:ext4_free_blocks+0x95e/0xa90
Call Trace:
<TASK>
? lock_timer_base+0x61/0x80
? __es_remove_extent+0x5a/0x760
? __mod_timer+0x256/0x380
? ext4_ind_truncate_ensure_credits+0x90/0x220
ext4_clear_blocks+0x107/0x1b0
ext4_free_data+0x15b/0x170
ext4_ind_truncate+0x214/0x2c0
? _raw_spin_unlock+0x15/0x30
? ext4_discard_preallocations+0x15a/0x410
? ext4_journal_check_start+0xe/0x90
? __ext4_journal_start_sb+0x2f/0x110
ext4_truncate+0x1b5/0x460
? __ext4_journal_start_sb+0x2f/0x110
ext4_evict_inode+0x2b4/0x6f0
evict+0xd0/0x1d0
ext4_enable_quotas+0x11f/0x1f0
ext4_orphan_cleanup+0x3de/0x430
? proc_create_seq_private+0x43/0x50
ext4_fill_super+0x295f/0x3ae0
? snprintf+0x39/0x40
? sget_fc+0x19c/0x330
? ext4_reconfigure+0x850/0x850
get_tree_bdev+0x16d/0x260
vfs_get_tree+0x25/0xb0
path_mount+0x431/0xa70
__x64_sys_mount+0xe2/0x120
do_syscall_64+0x5b/0x80
? do_user_addr_fault+0x1e2/0x670
? exc_page_fault+0x70/0x170
entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7fdf4e512ace
Fix it by making sure that the block range is properly validated before
used every time it changes in ext4_free_blocks() or ext4_mb_clear_bb().
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: dw-axi-dmac: ignore interrupt if no descriptor
If the channel has no descriptor and the interrupt is raised then the
kernel will OOPS. Check the result of vchan_next_desc() in the handler
axi_chan_block_xfer_complete() to avoid the error happening.
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: dw-axi-dmac: do not print NULL LLI during error
During debugging we have seen an issue where axi_chan_dump_lli()
is passed a NULL LLI pointer which ends up causing an OOPS due
to trying to get fields from it. Simply print NULL LLI and exit
to avoid this.
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix null-ptr-deref in f2fs_get_dnode_of_data
There is issue as follows when test f2fs atomic write:
F2FS-fs (loop0): Can't find valid F2FS filesystem in 2th superblock
F2FS-fs (loop0): invalid crc_offset: 0
F2FS-fs (loop0): f2fs_check_nid_range: out-of-range nid=1, run fsck to fix.
F2FS-fs (loop0): f2fs_check_nid_range: out-of-range nid=2, run fsck to fix.
==================================================================
BUG: KASAN: null-ptr-deref in f2fs_get_dnode_of_data+0xac/0x16d0
Read of size 8 at addr 0000000000000028 by task rep/1990
CPU: 4 PID: 1990 Comm: rep Not tainted 5.19.0-rc6-next-20220715 #266
Call Trace:
<TASK>
dump_stack_lvl+0x6e/0x91
print_report.cold+0x49a/0x6bb
kasan_report+0xa8/0x130
f2fs_get_dnode_of_data+0xac/0x16d0
f2fs_do_write_data_page+0x2a5/0x1030
move_data_page+0x3c5/0xdf0
do_garbage_collect+0x2015/0x36c0
f2fs_gc+0x554/0x1d30
f2fs_balance_fs+0x7f5/0xda0
f2fs_write_single_data_page+0xb66/0xdc0
f2fs_write_cache_pages+0x716/0x1420
f2fs_write_data_pages+0x84f/0x9a0
do_writepages+0x130/0x3a0
filemap_fdatawrite_wbc+0x87/0xa0
file_write_and_wait_range+0x157/0x1c0
f2fs_do_sync_file+0x206/0x12d0
f2fs_sync_file+0x99/0xc0
vfs_fsync_range+0x75/0x140
f2fs_file_write_iter+0xd7b/0x1850
vfs_write+0x645/0x780
ksys_write+0xf1/0x1e0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
As 3db1de0e582c commit changed atomic write way which new a cow_inode for
atomic write file, and also mark cow_inode as FI_ATOMIC_FILE.
When f2fs_do_write_data_page write cow_inode will use cow_inode's cow_inode
which is NULL. Then will trigger null-ptr-deref.
To solve above issue, introduce FI_COW_FILE flag for COW inode.
Fiexes: 3db1de0e582c("f2fs: change the current atomic write way")
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix locking in rxrpc's sendmsg
Fix three bugs in the rxrpc's sendmsg implementation:
(1) rxrpc_new_client_call() should release the socket lock when returning
an error from rxrpc_get_call_slot().
(2) rxrpc_wait_for_tx_window_intr() will return without the call mutex
held in the event that we're interrupted by a signal whilst waiting
for tx space on the socket or relocking the call mutex afterwards.
Fix this by: (a) moving the unlock/lock of the call mutex up to
rxrpc_send_data() such that the lock is not held around all of
rxrpc_wait_for_tx_window*() and (b) indicating to higher callers
whether we're return with the lock dropped. Note that this means
recvmsg() will not block on this call whilst we're waiting.
(3) After dropping and regaining the call mutex, rxrpc_send_data() needs
to go and recheck the state of the tx_pending buffer and the
tx_total_len check in case we raced with another sendmsg() on the same
call.
Thinking on this some more, it might make sense to have different locks for
sendmsg() and recvmsg(). There's probably no need to make recvmsg() wait
for sendmsg(). It does mean that recvmsg() can return MSG_EOR indicating
that a call is dead before a sendmsg() to that call returns - but that can
currently happen anyway.
Without fix (2), something like the following can be induced:
WARNING: bad unlock balance detected!
5.16.0-rc6-syzkaller #0 Not tainted
-------------------------------------
syz-executor011/3597 is trying to release lock (&call->user_mutex) at:
[<ffffffff885163a3>] rxrpc_do_sendmsg+0xc13/0x1350 net/rxrpc/sendmsg.c:748
but there are no more locks to release!
other info that might help us debug this:
no locks held by syz-executor011/3597.
...
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_unlock_imbalance_bug include/trace/events/lock.h:58 [inline]
__lock_release kernel/locking/lockdep.c:5306 [inline]
lock_release.cold+0x49/0x4e kernel/locking/lockdep.c:5657
__mutex_unlock_slowpath+0x99/0x5e0 kernel/locking/mutex.c:900
rxrpc_do_sendmsg+0xc13/0x1350 net/rxrpc/sendmsg.c:748
rxrpc_sendmsg+0x420/0x630 net/rxrpc/af_rxrpc.c:561
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:724
____sys_sendmsg+0x6e8/0x810 net/socket.c:2409
___sys_sendmsg+0xf3/0x170 net/socket.c:2463
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2492
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+0x44/0xae
[Thanks to Hawkins Jiawei and Khalid Masum for their attempts to fix this]
In the Linux kernel, the following vulnerability has been resolved:
xen/privcmd: fix error exit of privcmd_ioctl_dm_op()
The error exit of privcmd_ioctl_dm_op() is calling unlock_pages()
potentially with pages being NULL, leading to a NULL dereference.
Additionally lock_pages() doesn't check for pin_user_pages_fast()
having been completely successful, resulting in potentially not
locking all pages into memory. This could result in sporadic failures
when using the related memory in user mode.
Fix all of that by calling unlock_pages() always with the real number
of pinned pages, which will be zero in case pages being NULL, and by
checking the number of pages pinned by pin_user_pages_fast() matching
the expected number of pages.
In the Linux kernel, the following vulnerability has been resolved:
loop: Check for overflow while configuring loop
The userspace can configure a loop using an ioctl call, wherein
a configuration of type loop_config is passed (see lo_ioctl()'s
case on line 1550 of drivers/block/loop.c). This proceeds to call
loop_configure() which in turn calls loop_set_status_from_info()
(see line 1050 of loop.c), passing &config->info which is of type
loop_info64*. This function then sets the appropriate values, like
the offset.
loop_device has lo_offset of type loff_t (see line 52 of loop.c),
which is typdef-chained to long long, whereas loop_info64 has
lo_offset of type __u64 (see line 56 of include/uapi/linux/loop.h).
The function directly copies offset from info to the device as
follows (See line 980 of loop.c):
lo->lo_offset = info->lo_offset;
This results in an overflow, which triggers a warning in iomap_iter()
due to a call to iomap_iter_done() which has:
WARN_ON_ONCE(iter->iomap.offset > iter->pos);
Thus, check for negative value during loop_set_status_from_info().
Bug report: https://syzkaller.appspot.com/bug?id=c620fe14aac810396d3c3edc9ad73848bf69a29e