In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to do sanity check on node blkaddr in truncate_node()
syzbot reports a f2fs bug as below:
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:2534!
RIP: 0010:f2fs_invalidate_blocks+0x35f/0x370 fs/f2fs/segment.c:2534
Call Trace:
truncate_node+0x1ae/0x8c0 fs/f2fs/node.c:909
f2fs_remove_inode_page+0x5c2/0x870 fs/f2fs/node.c:1288
f2fs_evict_inode+0x879/0x15c0 fs/f2fs/inode.c:856
evict+0x4e8/0x9b0 fs/inode.c:723
f2fs_handle_failed_inode+0x271/0x2e0 fs/f2fs/inode.c:986
f2fs_create+0x357/0x530 fs/f2fs/namei.c:394
lookup_open fs/namei.c:3595 [inline]
open_last_lookups fs/namei.c:3694 [inline]
path_openat+0x1c03/0x3590 fs/namei.c:3930
do_filp_open+0x235/0x490 fs/namei.c:3960
do_sys_openat2+0x13e/0x1d0 fs/open.c:1415
do_sys_open fs/open.c:1430 [inline]
__do_sys_openat fs/open.c:1446 [inline]
__se_sys_openat fs/open.c:1441 [inline]
__x64_sys_openat+0x247/0x2a0 fs/open.c:1441
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0010:f2fs_invalidate_blocks+0x35f/0x370 fs/f2fs/segment.c:2534
The root cause is: on a fuzzed image, blkaddr in nat entry may be
corrupted, then it will cause system panic when using it in
f2fs_invalidate_blocks(), to avoid this, let's add sanity check on
nat blkaddr in truncate_node().
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: u_serial: Fix the issue that gs_start_io crashed due to accessing null pointer
Considering that in some extreme cases,
when u_serial driver is accessed by multiple threads,
Thread A is executing the open operation and calling the gs_open,
Thread B is executing the disconnect operation and calling the
gserial_disconnect function,The port->port_usb pointer will be set to NULL.
E.g.
Thread A Thread B
gs_open() gadget_unbind_driver()
gs_start_io() composite_disconnect()
gs_start_rx() gserial_disconnect()
... ...
spin_unlock(&port->port_lock)
status = usb_ep_queue() spin_lock(&port->port_lock)
spin_lock(&port->port_lock) port->port_usb = NULL
gs_free_requests(port->port_usb->in) spin_unlock(&port->port_lock)
Crash
This causes thread A to access a null pointer (port->port_usb is null)
when calling the gs_free_requests function, causing a crash.
If port_usb is NULL, the release request will be skipped as it
will be done by gserial_disconnect.
So add a null pointer check to gs_start_io before attempting
to access the value of the pointer port->port_usb.
Call trace:
gs_start_io+0x164/0x25c
gs_open+0x108/0x13c
tty_open+0x314/0x638
chrdev_open+0x1b8/0x258
do_dentry_open+0x2c4/0x700
vfs_open+0x2c/0x3c
path_openat+0xa64/0xc60
do_filp_open+0xb8/0x164
do_sys_openat2+0x84/0xf0
__arm64_sys_openat+0x70/0x9c
invoke_syscall+0x58/0x114
el0_svc_common+0x80/0xe0
do_el0_svc+0x1c/0x28
el0_svc+0x38/0x68
In the Linux kernel, the following vulnerability has been resolved:
dccp: Fix memory leak in dccp_feat_change_recv
If dccp_feat_push_confirm() fails after new value for SP feature was accepted
without reconciliation ('entry == NULL' branch), memory allocated for that value
with dccp_feat_clone_sp_val() is never freed.
Here is the kmemleak stack for this:
unreferenced object 0xffff88801d4ab488 (size 8):
comm "syz-executor310", pid 1127, jiffies 4295085598 (age 41.666s)
hex dump (first 8 bytes):
01 b4 4a 1d 80 88 ff ff ..J.....
backtrace:
[<00000000db7cabfe>] kmemdup+0x23/0x50 mm/util.c:128
[<0000000019b38405>] kmemdup include/linux/string.h:465 [inline]
[<0000000019b38405>] dccp_feat_clone_sp_val net/dccp/feat.c:371 [inline]
[<0000000019b38405>] dccp_feat_clone_sp_val net/dccp/feat.c:367 [inline]
[<0000000019b38405>] dccp_feat_change_recv net/dccp/feat.c:1145 [inline]
[<0000000019b38405>] dccp_feat_parse_options+0x1196/0x2180 net/dccp/feat.c:1416
[<00000000b1f6d94a>] dccp_parse_options+0xa2a/0x1260 net/dccp/options.c:125
[<0000000030d7b621>] dccp_rcv_state_process+0x197/0x13d0 net/dccp/input.c:650
[<000000001f74c72e>] dccp_v4_do_rcv+0xf9/0x1a0 net/dccp/ipv4.c:688
[<00000000a6c24128>] sk_backlog_rcv include/net/sock.h:1041 [inline]
[<00000000a6c24128>] __release_sock+0x139/0x3b0 net/core/sock.c:2570
[<00000000cf1f3a53>] release_sock+0x54/0x1b0 net/core/sock.c:3111
[<000000008422fa23>] inet_wait_for_connect net/ipv4/af_inet.c:603 [inline]
[<000000008422fa23>] __inet_stream_connect+0x5d0/0xf70 net/ipv4/af_inet.c:696
[<0000000015b6f64d>] inet_stream_connect+0x53/0xa0 net/ipv4/af_inet.c:735
[<0000000010122488>] __sys_connect_file+0x15c/0x1a0 net/socket.c:1865
[<00000000b4b70023>] __sys_connect+0x165/0x1a0 net/socket.c:1882
[<00000000f4cb3815>] __do_sys_connect net/socket.c:1892 [inline]
[<00000000f4cb3815>] __se_sys_connect net/socket.c:1889 [inline]
[<00000000f4cb3815>] __x64_sys_connect+0x6e/0xb0 net/socket.c:1889
[<00000000e7b1e839>] do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
[<0000000055e91434>] entry_SYSCALL_64_after_hwframe+0x67/0xd1
Clean up the allocated memory in case of dccp_feat_push_confirm() failure
and bail out with an error reset code.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
In the Linux kernel, the following vulnerability has been resolved:
net/ipv6: release expired exception dst cached in socket
Dst objects get leaked in ip6_negative_advice() when this function is
executed for an expired IPv6 route located in the exception table. There
are several conditions that must be fulfilled for the leak to occur:
* an ICMPv6 packet indicating a change of the MTU for the path is received,
resulting in an exception dst being created
* a TCP connection that uses the exception dst for routing packets must
start timing out so that TCP begins retransmissions
* after the exception dst expires, the FIB6 garbage collector must not run
before TCP executes ip6_negative_advice() for the expired exception dst
When TCP executes ip6_negative_advice() for an exception dst that has
expired and if no other socket holds a reference to the exception dst, the
refcount of the exception dst is 2, which corresponds to the increment
made by dst_init() and the increment made by the TCP socket for which the
connection is timing out. The refcount made by the socket is never
released. The refcount of the dst is decremented in sk_dst_reset() but
that decrement is counteracted by a dst_hold() intentionally placed just
before the sk_dst_reset() in ip6_negative_advice(). After
ip6_negative_advice() has finished, there is no other object tied to the
dst. The socket lost its reference stored in sk_dst_cache and the dst is
no longer in the exception table. The exception dst becomes a leaked
object.
As a result of this dst leak, an unbalanced refcount is reported for the
loopback device of a net namespace being destroyed under kernels that do
not contain e5f80fcf869a ("ipv6: give an IPv6 dev to blackhole_netdev"):
unregister_netdevice: waiting for lo to become free. Usage count = 2
Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). The
patch that introduced the dst_hold() in ip6_negative_advice() was
92f1655aa2b22 ("net: fix __dst_negative_advice() race"). But 92f1655aa2b22
merely refactored the code with regards to the dst refcount so the issue
was present even before 92f1655aa2b22. The bug was introduced in
54c1a859efd9f ("ipv6: Don't drop cache route entry unless timer actually
expired.") where the expired cached route is deleted and the sk_dst_cache
member of the socket is set to NULL by calling dst_negative_advice() but
the refcount belonging to the socket is left unbalanced.
The IPv4 version - ipv4_negative_advice() - is not affected by this bug.
When the TCP connection times out ipv4_negative_advice() merely resets the
sk_dst_cache of the socket while decrementing the refcount of the
exception dst.
In the Linux kernel, the following vulnerability has been resolved:
net: Fix icmp host relookup triggering ip_rt_bug
arp link failure may trigger ip_rt_bug while xfrm enabled, call trace is:
WARNING: CPU: 0 PID: 0 at net/ipv4/route.c:1241 ip_rt_bug+0x14/0x20
Modules linked in:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.0-rc6-00077-g2e1b3cc9d7f7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:ip_rt_bug+0x14/0x20
Call Trace:
<IRQ>
ip_send_skb+0x14/0x40
__icmp_send+0x42d/0x6a0
ipv4_link_failure+0xe2/0x1d0
arp_error_report+0x3c/0x50
neigh_invalidate+0x8d/0x100
neigh_timer_handler+0x2e1/0x330
call_timer_fn+0x21/0x120
__run_timer_base.part.0+0x1c9/0x270
run_timer_softirq+0x4c/0x80
handle_softirqs+0xac/0x280
irq_exit_rcu+0x62/0x80
sysvec_apic_timer_interrupt+0x77/0x90
The script below reproduces this scenario:
ip xfrm policy add src 0.0.0.0/0 dst 0.0.0.0/0 \
dir out priority 0 ptype main flag localok icmp
ip l a veth1 type veth
ip a a 192.168.141.111/24 dev veth0
ip l s veth0 up
ping 192.168.141.155 -c 1
icmp_route_lookup() create input routes for locally generated packets
while xfrm relookup ICMP traffic.Then it will set input route
(dst->out = ip_rt_bug) to skb for DESTUNREACH.
For ICMP err triggered by locally generated packets, dst->dev of output
route is loopback. Generally, xfrm relookup verification is not required
on loopback interfaces (net.ipv4.conf.lo.disable_xfrm = 1).
Skip icmp relookup for locally generated packets to fix it.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: x_tables: fix LED ID check in led_tg_check()
Syzbot has reported the following BUG detected by KASAN:
BUG: KASAN: slab-out-of-bounds in strlen+0x58/0x70
Read of size 1 at addr ffff8881022da0c8 by task repro/5879
...
Call Trace:
<TASK>
dump_stack_lvl+0x241/0x360
? __pfx_dump_stack_lvl+0x10/0x10
? __pfx__printk+0x10/0x10
? _printk+0xd5/0x120
? __virt_addr_valid+0x183/0x530
? __virt_addr_valid+0x183/0x530
print_report+0x169/0x550
? __virt_addr_valid+0x183/0x530
? __virt_addr_valid+0x183/0x530
? __virt_addr_valid+0x45f/0x530
? __phys_addr+0xba/0x170
? strlen+0x58/0x70
kasan_report+0x143/0x180
? strlen+0x58/0x70
strlen+0x58/0x70
kstrdup+0x20/0x80
led_tg_check+0x18b/0x3c0
xt_check_target+0x3bb/0xa40
? __pfx_xt_check_target+0x10/0x10
? stack_depot_save_flags+0x6e4/0x830
? nft_target_init+0x174/0xc30
nft_target_init+0x82d/0xc30
? __pfx_nft_target_init+0x10/0x10
? nf_tables_newrule+0x1609/0x2980
? nf_tables_newrule+0x1609/0x2980
? rcu_is_watching+0x15/0xb0
? nf_tables_newrule+0x1609/0x2980
? nf_tables_newrule+0x1609/0x2980
? __kmalloc_noprof+0x21a/0x400
nf_tables_newrule+0x1860/0x2980
? __pfx_nf_tables_newrule+0x10/0x10
? __nla_parse+0x40/0x60
nfnetlink_rcv+0x14e5/0x2ab0
? __pfx_validate_chain+0x10/0x10
? __pfx_nfnetlink_rcv+0x10/0x10
? __lock_acquire+0x1384/0x2050
? netlink_deliver_tap+0x2e/0x1b0
? __pfx_lock_release+0x10/0x10
? netlink_deliver_tap+0x2e/0x1b0
netlink_unicast+0x7f8/0x990
? __pfx_netlink_unicast+0x10/0x10
? __virt_addr_valid+0x183/0x530
? __check_object_size+0x48e/0x900
netlink_sendmsg+0x8e4/0xcb0
? __pfx_netlink_sendmsg+0x10/0x10
? aa_sock_msg_perm+0x91/0x160
? __pfx_netlink_sendmsg+0x10/0x10
__sock_sendmsg+0x223/0x270
____sys_sendmsg+0x52a/0x7e0
? __pfx_____sys_sendmsg+0x10/0x10
__sys_sendmsg+0x292/0x380
? __pfx___sys_sendmsg+0x10/0x10
? lockdep_hardirqs_on_prepare+0x43d/0x780
? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
? exc_page_fault+0x590/0x8c0
? do_syscall_64+0xb6/0x230
do_syscall_64+0xf3/0x230
entry_SYSCALL_64_after_hwframe+0x77/0x7f
...
</TASK>
Since an invalid (without '\0' byte at all) byte sequence may be passed
from userspace, add an extra check to ensure that such a sequence is
rejected as possible ID and so never passed to 'kstrdup()' and further.
In the Linux kernel, the following vulnerability has been resolved:
drm/dp_mst: Fix MST sideband message body length check
Fix the MST sideband message body length check, which must be at least 1
byte accounting for the message body CRC (aka message data CRC) at the
end of the message.
This fixes a case where an MST branch device returns a header with a
correct header CRC (indicating a correctly received body length), with
the body length being incorrectly set to 0. This will later lead to a
memory corruption in drm_dp_sideband_append_payload() and the following
errors in dmesg:
UBSAN: array-index-out-of-bounds in drivers/gpu/drm/display/drm_dp_mst_topology.c:786:25
index -1 is out of range for type 'u8 [48]'
Call Trace:
drm_dp_sideband_append_payload+0x33d/0x350 [drm_display_helper]
drm_dp_get_one_sb_msg+0x3ce/0x5f0 [drm_display_helper]
drm_dp_mst_hpd_irq_handle_event+0xc8/0x1580 [drm_display_helper]
memcpy: detected field-spanning write (size 18446744073709551615) of single field "&msg->msg[msg->curlen]" at drivers/gpu/drm/display/drm_dp_mst_topology.c:791 (size 256)
Call Trace:
drm_dp_sideband_append_payload+0x324/0x350 [drm_display_helper]
drm_dp_get_one_sb_msg+0x3ce/0x5f0 [drm_display_helper]
drm_dp_mst_hpd_irq_handle_event+0xc8/0x1580 [drm_display_helper]
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix potential out-of-bounds memory access in nilfs_find_entry()
Syzbot reported that when searching for records in a directory where the
inode's i_size is corrupted and has a large value, memory access outside
the folio/page range may occur, or a use-after-free bug may be detected if
KASAN is enabled.
This is because nilfs_last_byte(), which is called by nilfs_find_entry()
and others to calculate the number of valid bytes of directory data in a
page from i_size and the page index, loses the upper 32 bits of the 64-bit
size information due to an inappropriate type of local variable to which
the i_size value is assigned.
This caused a large byte offset value due to underflow in the end address
calculation in the calling nilfs_find_entry(), resulting in memory access
that exceeds the folio/page size.
Fix this issue by changing the type of the local variable causing the bit
loss from "unsigned int" to "u64". The return value of nilfs_last_byte()
is also of type "unsigned int", but it is truncated so as not to exceed
PAGE_SIZE and no bit loss occurs, so no change is required.
In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix use after free on unload
System crash is observed with stack trace warning of use after
free. There are 2 signals to tell dpc_thread to terminate (UNLOADING
flag and kthread_stop).
On setting the UNLOADING flag when dpc_thread happens to run at the time
and sees the flag, this causes dpc_thread to exit and clean up
itself. When kthread_stop is called for final cleanup, this causes use
after free.
Remove UNLOADING signal to terminate dpc_thread. Use the kthread_stop
as the main signal to exit dpc_thread.
[596663.812935] kernel BUG at mm/slub.c:294!
[596663.812950] invalid opcode: 0000 [#1] SMP PTI
[596663.812957] CPU: 13 PID: 1475935 Comm: rmmod Kdump: loaded Tainted: G IOE --------- - - 4.18.0-240.el8.x86_64 #1
[596663.812960] Hardware name: HP ProLiant DL380p Gen8, BIOS P70 08/20/2012
[596663.812974] RIP: 0010:__slab_free+0x17d/0x360
...
[596663.813008] Call Trace:
[596663.813022] ? __dentry_kill+0x121/0x170
[596663.813030] ? _cond_resched+0x15/0x30
[596663.813034] ? _cond_resched+0x15/0x30
[596663.813039] ? wait_for_completion+0x35/0x190
[596663.813048] ? try_to_wake_up+0x63/0x540
[596663.813055] free_task+0x5a/0x60
[596663.813061] kthread_stop+0xf3/0x100
[596663.813103] qla2x00_remove_one+0x284/0x440 [qla2xxx]