In the Linux kernel, the following vulnerability has been resolved:
drivers:md:fix a potential use-after-free bug
In line 2884, "raid5_release_stripe(sh);" drops the reference to sh and
may cause sh to be released. However, sh is subsequently used in lines
2886 "if (sh->batch_head && sh != sh->batch_head)". This may result in an
use-after-free bug.
It can be fixed by moving "raid5_release_stripe(sh);" to the bottom of
the function.
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:
cxl: Fix a memory leak in an error handling path
A bitmap_zalloc() must be balanced by a corresponding bitmap_free() in the
error handling path of afu_allocate_irqs().
In the Linux kernel, the following vulnerability has been resolved:
powerpc/64: Init jump labels before parse_early_param()
On 64-bit, calling jump_label_init() in setup_feature_keys() is too
late because static keys may be used in subroutines of
parse_early_param() which is again subroutine of early_init_devtree().
For example booting with "threadirqs":
static_key_enable_cpuslocked(): static key '0xc000000002953260' used before call to jump_label_init()
WARNING: CPU: 0 PID: 0 at kernel/jump_label.c:166 static_key_enable_cpuslocked+0xfc/0x120
...
NIP static_key_enable_cpuslocked+0xfc/0x120
LR static_key_enable_cpuslocked+0xf8/0x120
Call Trace:
static_key_enable_cpuslocked+0xf8/0x120 (unreliable)
static_key_enable+0x30/0x50
setup_forced_irqthreads+0x28/0x40
do_early_param+0xa0/0x108
parse_args+0x290/0x4e0
parse_early_options+0x48/0x5c
parse_early_param+0x58/0x84
early_init_devtree+0xd4/0x518
early_setup+0xb4/0x214
So call jump_label_init() just before parse_early_param() in
early_init_devtree().
[mpe: Add call trace to change log and minor wording edits.]
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid use f2fs_bug_on() in f2fs_new_node_page()
As Dipanjan Das <mail.dipanjan.das@gmail.com> reported, syzkaller
found a f2fs bug as below:
RIP: 0010:f2fs_new_node_page+0x19ac/0x1fc0 fs/f2fs/node.c:1295
Call Trace:
write_all_xattrs fs/f2fs/xattr.c:487 [inline]
__f2fs_setxattr+0xe76/0x2e10 fs/f2fs/xattr.c:743
f2fs_setxattr+0x233/0xab0 fs/f2fs/xattr.c:790
f2fs_xattr_generic_set+0x133/0x170 fs/f2fs/xattr.c:86
__vfs_setxattr+0x115/0x180 fs/xattr.c:182
__vfs_setxattr_noperm+0x125/0x5f0 fs/xattr.c:216
__vfs_setxattr_locked+0x1cf/0x260 fs/xattr.c:277
vfs_setxattr+0x13f/0x330 fs/xattr.c:303
setxattr+0x146/0x160 fs/xattr.c:611
path_setxattr+0x1a7/0x1d0 fs/xattr.c:630
__do_sys_lsetxattr fs/xattr.c:653 [inline]
__se_sys_lsetxattr fs/xattr.c:649 [inline]
__x64_sys_lsetxattr+0xbd/0x150 fs/xattr.c:649
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+0x46/0xb0
NAT entry and nat bitmap can be inconsistent, e.g. one nid is free
in nat bitmap, and blkaddr in its NAT entry is not NULL_ADDR, it
may trigger BUG_ON() in f2fs_new_node_page(), fix it.
In the Linux kernel, the following vulnerability has been resolved:
mips: cavium-octeon: Fix missing of_node_put() in octeon2_usb_clocks_start
We should call of_node_put() for the reference 'uctl_node' returned by
of_get_parent() which will increase the refcount. Otherwise, there will
be a refcount leak bug.
In the Linux kernel, the following vulnerability has been resolved:
xfrm: fix refcount leak in __xfrm_policy_check()
The issue happens on an error path in __xfrm_policy_check(). When the
fetching process of the object `pols[1]` fails, the function simply
returns 0, forgetting to decrement the reference count of `pols[0]`,
which is incremented earlier by either xfrm_sk_policy_lookup() or
xfrm_policy_lookup(). This may result in memory leaks.
Fix it by decreasing the reference count of `pols[0]` in that path.
In the Linux kernel, the following vulnerability has been resolved:
kprobes: don't call disarm_kprobe() for disabled kprobes
The assumption in __disable_kprobe() is wrong, and it could try to disarm
an already disarmed kprobe and fire the WARN_ONCE() below. [0] We can
easily reproduce this issue.
1. Write 0 to /sys/kernel/debug/kprobes/enabled.
# echo 0 > /sys/kernel/debug/kprobes/enabled
2. Run execsnoop. At this time, one kprobe is disabled.
# /usr/share/bcc/tools/execsnoop &
[1] 2460
PCOMM PID PPID RET ARGS
# cat /sys/kernel/debug/kprobes/list
ffffffff91345650 r __x64_sys_execve+0x0 [FTRACE]
ffffffff91345650 k __x64_sys_execve+0x0 [DISABLED][FTRACE]
3. Write 1 to /sys/kernel/debug/kprobes/enabled, which changes
kprobes_all_disarmed to false but does not arm the disabled kprobe.
# echo 1 > /sys/kernel/debug/kprobes/enabled
# cat /sys/kernel/debug/kprobes/list
ffffffff91345650 r __x64_sys_execve+0x0 [FTRACE]
ffffffff91345650 k __x64_sys_execve+0x0 [DISABLED][FTRACE]
4. Kill execsnoop, when __disable_kprobe() calls disarm_kprobe() for the
disabled kprobe and hits the WARN_ONCE() in __disarm_kprobe_ftrace().
# fg
/usr/share/bcc/tools/execsnoop
^C
Actually, WARN_ONCE() is fired twice, and __unregister_kprobe_top() misses
some cleanups and leaves the aggregated kprobe in the hash table. Then,
__unregister_trace_kprobe() initialises tk->rp.kp.list and creates an
infinite loop like this.
aggregated kprobe.list -> kprobe.list -.
^ |
'.__.'
In this situation, these commands fall into the infinite loop and result
in RCU stall or soft lockup.
cat /sys/kernel/debug/kprobes/list : show_kprobe_addr() enters into the
infinite loop with RCU.
/usr/share/bcc/tools/execsnoop : warn_kprobe_rereg() holds kprobe_mutex,
and __get_valid_kprobe() is stuck in
the loop.
To avoid the issue, make sure we don't call disarm_kprobe() for disabled
kprobes.
[0]
Failed to disarm kprobe-ftrace at __x64_sys_execve+0x0/0x40 (error -2)
WARNING: CPU: 6 PID: 2460 at kernel/kprobes.c:1130 __disarm_kprobe_ftrace.isra.19 (kernel/kprobes.c:1129)
Modules linked in: ena
CPU: 6 PID: 2460 Comm: execsnoop Not tainted 5.19.0+ #28
Hardware name: Amazon EC2 c5.2xlarge/, BIOS 1.0 10/16/2017
RIP: 0010:__disarm_kprobe_ftrace.isra.19 (kernel/kprobes.c:1129)
Code: 24 8b 02 eb c1 80 3d c4 83 f2 01 00 75 d4 48 8b 75 00 89 c2 48 c7 c7 90 fa 0f 92 89 04 24 c6 05 ab 83 01 e8 e4 94 f0 ff <0f> 0b 8b 04 24 eb b1 89 c6 48 c7 c7 60 fa 0f 92 89 04 24 e8 cc 94
RSP: 0018:ffff9e6ec154bd98 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffffff930f7b00 RCX: 0000000000000001
RDX: 0000000080000001 RSI: ffffffff921461c5 RDI: 00000000ffffffff
RBP: ffff89c504286da8 R08: 0000000000000000 R09: c0000000fffeffff
R10: 0000000000000000 R11: ffff9e6ec154bc28 R12: ffff89c502394e40
R13: ffff89c502394c00 R14: ffff9e6ec154bc00 R15: 0000000000000000
FS: 00007fe800398740(0000) GS:ffff89c812d80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00057f010 CR3: 0000000103b54006 CR4: 00000000007706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
__disable_kprobe (kernel/kprobes.c:1716)
disable_kprobe (kernel/kprobes.c:2392)
__disable_trace_kprobe (kernel/trace/trace_kprobe.c:340)
disable_trace_kprobe (kernel/trace/trace_kprobe.c:429)
perf_trace_event_unreg.isra.2 (./include/linux/tracepoint.h:93 kernel/trace/trace_event_perf.c:168)
perf_kprobe_destroy (kernel/trace/trace_event_perf.c:295)
_free_event (kernel/events/core.c:4971)
perf_event_release_kernel (kernel/events/core.c:5176)
perf_release (kernel/events/core.c:5186)
__fput (fs/file_table.c:321)
task_work_run (./include/linux/
---truncated---