| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
blk-mq: fix blk_mq_tags double free while nr_requests grown
In the case user trigger tags grow by queue sysfs attribute nr_requests,
hctx->sched_tags will be freed directly and replaced with a new
allocated tags, see blk_mq_tag_update_depth().
The problem is that hctx->sched_tags is from elevator->et->tags, while
et->tags is still the freed tags, hence later elevator exit will try to
free the tags again, causing kernel panic.
Fix this problem by replacing et->tags with new allocated tags as well.
Noted there are still some long term problems that will require some
refactor to be fixed thoroughly[1].
[1] https://lore.kernel.org/all/20250815080216.410665-1-yukuai1@huaweicloud.com/ |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_qfq: Fix null-deref in agg_dequeue
To prevent a potential crash in agg_dequeue (net/sched/sch_qfq.c)
when cl->qdisc->ops->peek(cl->qdisc) returns NULL, we check the return
value before using it, similar to the existing approach in sch_hfsc.c.
To avoid code duplication, the following changes are made:
1. Changed qdisc_warn_nonwc(include/net/pkt_sched.h) into a static
inline function.
2. Moved qdisc_peek_len from net/sched/sch_hfsc.c to
include/net/pkt_sched.h so that sch_qfq can reuse it.
3. Applied qdisc_peek_len in agg_dequeue to avoid crashing. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: mpi3mr: Fix an issue found by KASAN
Write only correct size (32 instead of 64 bytes). |
| In the Linux kernel, the following vulnerability has been resolved:
rpmsg: glink: Add check for kstrdup
Add check for the return value of kstrdup() and return the error
if it fails in order to avoid NULL pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
netpoll: Fix deadlock in memory allocation under spinlock
Fix a AA deadlock in refill_skbs() where memory allocation while holding
skb_pool->lock can trigger a recursive lock acquisition attempt.
The deadlock scenario occurs when the system is under severe memory
pressure:
1. refill_skbs() acquires skb_pool->lock (spinlock)
2. alloc_skb() is called while holding the lock
3. Memory allocator fails and calls slab_out_of_memory()
4. This triggers printk() for the OOM warning
5. The console output path calls netpoll_send_udp()
6. netpoll_send_udp() attempts to acquire the same skb_pool->lock
7. Deadlock: the lock is already held by the same CPU
Call stack:
refill_skbs()
spin_lock_irqsave(&skb_pool->lock) <- lock acquired
__alloc_skb()
kmem_cache_alloc_node_noprof()
slab_out_of_memory()
printk()
console_flush_all()
netpoll_send_udp()
skb_dequeue()
spin_lock_irqsave(&skb_pool->lock) <- deadlock attempt
This bug was exposed by commit 248f6571fd4c51 ("netpoll: Optimize skb
refilling on critical path") which removed refill_skbs() from the
critical path (where nested printk was being deferred), letting nested
printk being called from inside refill_skbs()
Refactor refill_skbs() to never allocate memory while holding
the spinlock.
Another possible solution to fix this problem is protecting the
refill_skbs() from nested printks, basically calling
printk_deferred_{enter,exit}() in refill_skbs(), then, any nested
pr_warn() would be deferred.
I prefer this approach, given I _think_ it might be a good idea to move
the alloc_skb() from GFP_ATOMIC to GFP_KERNEL in the future, so, having
the alloc_skb() outside of the lock will be necessary step.
There is a possible TOCTOU issue when checking for the pool length, and
queueing the new allocated skb, but, this is not an issue, given that
an extra SKB in the pool is harmless and it will be eventually used. |
| In the Linux kernel before 4.8, usb_parse_endpoint in drivers/usb/core/config.c does not validate the wMaxPacketSize field of an endpoint descriptor. NOTE: This vulnerability only affects products that are no longer supported by the supplier. |
| In the Linux kernel, the following vulnerability has been resolved:
media: rc: fix races with imon_disconnect()
Syzbot reports a KASAN issue as below:
BUG: KASAN: use-after-free in __create_pipe include/linux/usb.h:1945 [inline]
BUG: KASAN: use-after-free in send_packet+0xa2d/0xbc0 drivers/media/rc/imon.c:627
Read of size 4 at addr ffff8880256fb000 by task syz-executor314/4465
CPU: 2 PID: 4465 Comm: syz-executor314 Not tainted 6.0.0-rc1-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:317 [inline]
print_report.cold+0x2ba/0x6e9 mm/kasan/report.c:433
kasan_report+0xb1/0x1e0 mm/kasan/report.c:495
__create_pipe include/linux/usb.h:1945 [inline]
send_packet+0xa2d/0xbc0 drivers/media/rc/imon.c:627
vfd_write+0x2d9/0x550 drivers/media/rc/imon.c:991
vfs_write+0x2d7/0xdd0 fs/read_write.c:576
ksys_write+0x127/0x250 fs/read_write.c:631
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+0x63/0xcd
The iMON driver improperly releases the usb_device reference in
imon_disconnect without coordinating with active users of the
device.
Specifically, the fields usbdev_intf0 and usbdev_intf1 are not
protected by the users counter (ictx->users). During probe,
imon_init_intf0 or imon_init_intf1 increments the usb_device
reference count depending on the interface. However, during
disconnect, usb_put_dev is called unconditionally, regardless of
actual usage.
As a result, if vfd_write or other operations are still in
progress after disconnect, this can lead to a use-after-free of
the usb_device pointer.
Thread 1 vfd_write Thread 2 imon_disconnect
...
if
usb_put_dev(ictx->usbdev_intf0)
else
usb_put_dev(ictx->usbdev_intf1)
...
while
send_packet
if
pipe = usb_sndintpipe(
ictx->usbdev_intf0) UAF
else
pipe = usb_sndctrlpipe(
ictx->usbdev_intf0, 0) UAF
Guard access to usbdev_intf0 and usbdev_intf1 after disconnect by
checking ictx->disconnected in all writer paths. Add early return
with -ENODEV in send_packet(), vfd_write(), lcd_write() and
display_open() if the device is no longer present.
Set and read ictx->disconnected under ictx->lock to ensure memory
synchronization. Acquire the lock in imon_disconnect() before setting
the flag to synchronize with any ongoing operations.
Ensure writers exit early and safely after disconnect before the USB
core proceeds with cleanup.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: smartpqi: Correct device removal for multi-actuator devices
Correct device count for multi-actuator drives which can cause kernel
panics. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Add bpf_prog_run_data_pointers()
syzbot found that cls_bpf_classify() is able to change
tc_skb_cb(skb)->drop_reason triggering a warning in sk_skb_reason_drop().
WARNING: CPU: 0 PID: 5965 at net/core/skbuff.c:1192 __sk_skb_reason_drop net/core/skbuff.c:1189 [inline]
WARNING: CPU: 0 PID: 5965 at net/core/skbuff.c:1192 sk_skb_reason_drop+0x76/0x170 net/core/skbuff.c:1214
struct tc_skb_cb has been added in commit ec624fe740b4 ("net/sched:
Extend qdisc control block with tc control block"), which added a wrong
interaction with db58ba459202 ("bpf: wire in data and data_end for
cls_act_bpf").
drop_reason was added later.
Add bpf_prog_run_data_pointers() helper to save/restore the net_sched
storage colliding with BPF data_meta/data_end. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_eem: Fix memory leak in eem_unwrap
The existing code did not handle the failure case of usb_ep_queue in the
command path, potentially leading to memory leaks.
Improve error handling to free all allocated resources on usb_ep_queue
failure. This patch continues to use goto logic for error handling, as the
existing error handling is complex and not easily adaptable to auto-cleanup
helpers.
kmemleak results:
unreferenced object 0xffffff895a512300 (size 240):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
kmem_cache_alloc+0x1b4/0x358
skb_clone+0x90/0xd8
eem_unwrap+0x1cc/0x36c
unreferenced object 0xffffff8a157f4000 (size 256):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
__kmem_cache_alloc_node+0x1b4/0x2dc
kmalloc_trace+0x48/0x140
dwc3_gadget_ep_alloc_request+0x58/0x11c
usb_ep_alloc_request+0x40/0xe4
eem_unwrap+0x204/0x36c
unreferenced object 0xffffff8aadbaac00 (size 128):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
__kmem_cache_alloc_node+0x1b4/0x2dc
__kmalloc+0x64/0x1a8
eem_unwrap+0x218/0x36c
unreferenced object 0xffffff89ccef3500 (size 64):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
__kmem_cache_alloc_node+0x1b4/0x2dc
kmalloc_trace+0x48/0x140
eem_unwrap+0x238/0x36c |
| In the Linux kernel, the following vulnerability has been resolved:
nvmet-fc: move lsop put work to nvmet_fc_ls_req_op
It’s possible for more than one async command to be in flight from
__nvmet_fc_send_ls_req. For each command, a tgtport reference is taken.
In the current code, only one put work item is queued at a time, which
results in a leaked reference.
To fix this, move the work item to the nvmet_fc_ls_req_op struct, which
already tracks all resources related to the command. |
| In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8192u: Fix use after free in ieee80211_rx()
We cannot dereference the "skb" pointer after calling
ieee80211_monitor_rx(), because it is a use after free. |
| In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum_router: Fix neighbour use-after-free
We sometimes observe use-after-free when dereferencing a neighbour [1].
The problem seems to be that the driver stores a pointer to the
neighbour, but without holding a reference on it. A reference is only
taken when the neighbour is used by a nexthop.
Fix by simplifying the reference counting scheme. Always take a
reference when storing a neighbour pointer in a neighbour entry. Avoid
taking a referencing when the neighbour is used by a nexthop as the
neighbour entry associated with the nexthop already holds a reference.
Tested by running the test that uncovered the problem over 300 times.
Without this patch the problem was reproduced after a handful of
iterations.
[1]
BUG: KASAN: slab-use-after-free in mlxsw_sp_neigh_entry_update+0x2d4/0x310
Read of size 8 at addr ffff88817f8e3420 by task ip/3929
CPU: 3 UID: 0 PID: 3929 Comm: ip Not tainted 6.18.0-rc4-virtme-g36b21a067510 #3 PREEMPT(full)
Hardware name: Nvidia SN5600/VMOD0013, BIOS 5.13 05/31/2023
Call Trace:
<TASK>
dump_stack_lvl+0x6f/0xa0
print_address_description.constprop.0+0x6e/0x300
print_report+0xfc/0x1fb
kasan_report+0xe4/0x110
mlxsw_sp_neigh_entry_update+0x2d4/0x310
mlxsw_sp_router_rif_gone_sync+0x35f/0x510
mlxsw_sp_rif_destroy+0x1ea/0x730
mlxsw_sp_inetaddr_port_vlan_event+0xa1/0x1b0
__mlxsw_sp_inetaddr_lag_event+0xcc/0x130
__mlxsw_sp_inetaddr_event+0xf5/0x3c0
mlxsw_sp_router_netdevice_event+0x1015/0x1580
notifier_call_chain+0xcc/0x150
call_netdevice_notifiers_info+0x7e/0x100
__netdev_upper_dev_unlink+0x10b/0x210
netdev_upper_dev_unlink+0x79/0xa0
vrf_del_slave+0x18/0x50
do_set_master+0x146/0x7d0
do_setlink.isra.0+0x9a0/0x2880
rtnl_newlink+0x637/0xb20
rtnetlink_rcv_msg+0x6fe/0xb90
netlink_rcv_skb+0x123/0x380
netlink_unicast+0x4a3/0x770
netlink_sendmsg+0x75b/0xc90
__sock_sendmsg+0xbe/0x160
____sys_sendmsg+0x5b2/0x7d0
___sys_sendmsg+0xfd/0x180
__sys_sendmsg+0x124/0x1c0
do_syscall_64+0xbb/0xfd0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
[...]
Allocated by task 109:
kasan_save_stack+0x30/0x50
kasan_save_track+0x14/0x30
__kasan_kmalloc+0x7b/0x90
__kmalloc_noprof+0x2c1/0x790
neigh_alloc+0x6af/0x8f0
___neigh_create+0x63/0xe90
mlxsw_sp_nexthop_neigh_init+0x430/0x7e0
mlxsw_sp_nexthop_type_init+0x212/0x960
mlxsw_sp_nexthop6_group_info_init.constprop.0+0x81f/0x1280
mlxsw_sp_nexthop6_group_get+0x392/0x6a0
mlxsw_sp_fib6_entry_create+0x46a/0xfd0
mlxsw_sp_router_fib6_replace+0x1ed/0x5f0
mlxsw_sp_router_fib6_event_work+0x10a/0x2a0
process_one_work+0xd57/0x1390
worker_thread+0x4d6/0xd40
kthread+0x355/0x5b0
ret_from_fork+0x1d4/0x270
ret_from_fork_asm+0x11/0x20
Freed by task 154:
kasan_save_stack+0x30/0x50
kasan_save_track+0x14/0x30
__kasan_save_free_info+0x3b/0x60
__kasan_slab_free+0x43/0x70
kmem_cache_free_bulk.part.0+0x1eb/0x5e0
kvfree_rcu_bulk+0x1f2/0x260
kfree_rcu_work+0x130/0x1b0
process_one_work+0xd57/0x1390
worker_thread+0x4d6/0xd40
kthread+0x355/0x5b0
ret_from_fork+0x1d4/0x270
ret_from_fork_asm+0x11/0x20
Last potentially related work creation:
kasan_save_stack+0x30/0x50
kasan_record_aux_stack+0x8c/0xa0
kvfree_call_rcu+0x93/0x5b0
mlxsw_sp_router_neigh_event_work+0x67d/0x860
process_one_work+0xd57/0x1390
worker_thread+0x4d6/0xd40
kthread+0x355/0x5b0
ret_from_fork+0x1d4/0x270
ret_from_fork_asm+0x11/0x20 |
| In the Linux kernel, the following vulnerability has been resolved:
pinctrl: stm32: Fix refcount leak in stm32_pctrl_get_irq_domain
of_irq_find_parent() returns a node pointer with refcount incremented,
We should use of_node_put() on it when not needed anymore.
Add missing of_node_put() to avoid refcount leak. |
| In the Linux kernel, the following vulnerability has been resolved:
net: core: remove unnecessary frame_sz check in bpf_xdp_adjust_tail()
Syzkaller reported the following issue:
=======================================
Too BIG xdp->frame_sz = 131072
WARNING: CPU: 0 PID: 5020 at net/core/filter.c:4121
____bpf_xdp_adjust_tail net/core/filter.c:4121 [inline]
WARNING: CPU: 0 PID: 5020 at net/core/filter.c:4121
bpf_xdp_adjust_tail+0x466/0xa10 net/core/filter.c:4103
...
Call Trace:
<TASK>
bpf_prog_4add87e5301a4105+0x1a/0x1c
__bpf_prog_run include/linux/filter.h:600 [inline]
bpf_prog_run_xdp include/linux/filter.h:775 [inline]
bpf_prog_run_generic_xdp+0x57e/0x11e0 net/core/dev.c:4721
netif_receive_generic_xdp net/core/dev.c:4807 [inline]
do_xdp_generic+0x35c/0x770 net/core/dev.c:4866
tun_get_user+0x2340/0x3ca0 drivers/net/tun.c:1919
tun_chr_write_iter+0xe8/0x210 drivers/net/tun.c:2043
call_write_iter include/linux/fs.h:1871 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x650/0xe40 fs/read_write.c:584
ksys_write+0x12f/0x250 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
xdp->frame_sz > PAGE_SIZE check was introduced in commit c8741e2bfe87
("xdp: Allow bpf_xdp_adjust_tail() to grow packet size"). But Jesper
Dangaard Brouer <jbrouer@redhat.com> noted that after introducing the
xdp_init_buff() which all XDP driver use - it's safe to remove this
check. The original intend was to catch cases where XDP drivers have
not been updated to use xdp.frame_sz, but that is not longer a concern
(since xdp_init_buff).
Running the initial syzkaller repro it was discovered that the
contiguous physical memory allocation is used for both xdp paths in
tun_get_user(), e.g. tun_build_skb() and tun_alloc_skb(). It was also
stated by Jesper Dangaard Brouer <jbrouer@redhat.com> that XDP can
work on higher order pages, as long as this is contiguous physical
memory (e.g. a page). |
| In the Linux kernel, the following vulnerability has been resolved:
configfs: fix possible memory leak in configfs_create_dir()
kmemleak reported memory leaks in configfs_create_dir():
unreferenced object 0xffff888009f6af00 (size 192):
comm "modprobe", pid 3777, jiffies 4295537735 (age 233.784s)
backtrace:
kmem_cache_alloc (mm/slub.c:3250 mm/slub.c:3256 mm/slub.c:3263 mm/slub.c:3273)
new_fragment (./include/linux/slab.h:600 fs/configfs/dir.c:163)
configfs_register_subsystem (fs/configfs/dir.c:1857)
basic_write (drivers/hwtracing/stm/p_basic.c:14) stm_p_basic
do_one_initcall (init/main.c:1296)
do_init_module (kernel/module/main.c:2455)
...
unreferenced object 0xffff888003ba7180 (size 96):
comm "modprobe", pid 3777, jiffies 4295537735 (age 233.784s)
backtrace:
kmem_cache_alloc (mm/slub.c:3250 mm/slub.c:3256 mm/slub.c:3263 mm/slub.c:3273)
configfs_new_dirent (./include/linux/slab.h:723 fs/configfs/dir.c:194)
configfs_make_dirent (fs/configfs/dir.c:248)
configfs_create_dir (fs/configfs/dir.c:296)
configfs_attach_group.isra.28 (fs/configfs/dir.c:816 fs/configfs/dir.c:852)
configfs_register_subsystem (fs/configfs/dir.c:1881)
basic_write (drivers/hwtracing/stm/p_basic.c:14) stm_p_basic
do_one_initcall (init/main.c:1296)
do_init_module (kernel/module/main.c:2455)
...
This is because the refcount is not correct in configfs_make_dirent().
For normal stage, the refcount is changing as:
configfs_register_subsystem()
configfs_create_dir()
configfs_make_dirent()
configfs_new_dirent() # set s_count = 1
dentry->d_fsdata = configfs_get(sd); # s_count = 2
...
configfs_unregister_subsystem()
configfs_remove_dir()
remove_dir()
configfs_remove_dirent() # s_count = 1
dput() ...
*dentry_unlink_inode()*
configfs_d_iput() # s_count = 0, release
However, if we failed in configfs_create():
configfs_register_subsystem()
configfs_create_dir()
configfs_make_dirent() # s_count = 2
...
configfs_create() # fail
->out_remove:
configfs_remove_dirent(dentry)
configfs_put(sd) # s_count = 1
return PTR_ERR(inode);
There is no inode in the error path, so the configfs_d_iput() is lost
and makes sd and fragment memory leaked.
To fix this, when we failed in configfs_create(), manually call
configfs_put(sd) to keep the refcount correct. |
| In the Linux kernel, the following vulnerability has been resolved:
x86/mm: Fix SMP ordering in switch_mm_irqs_off()
Stephen noted that it is possible to not have an smp_mb() between
the loaded_mm store and the tlb_gen load in switch_mm(), meaning the
ordering against flush_tlb_mm_range() goes out the window, and it
becomes possible for switch_mm() to not observe a recent tlb_gen
update and fail to flush the TLBs.
[ dhansen: merge conflict fixed by Ingo ] |
| In the Linux kernel, the following vulnerability has been resolved:
usb: cdns3: gadget: Use-after-free during failed initialization and exit of cdnsp gadget
In the __cdnsp_gadget_init() and cdnsp_gadget_exit() functions, the gadget
structure (pdev->gadget) was freed before its endpoints.
The endpoints are linked via the ep_list in the gadget structure.
Freeing the gadget first leaves dangling pointers in the endpoint list.
When the endpoints are subsequently freed, this results in a use-after-free.
Fix:
By separating the usb_del_gadget_udc() operation into distinct "del" and
"put" steps, cdnsp_gadget_free_endpoints() can be executed prior to the
final release of the gadget structure with usb_put_gadget().
A patch similar to bb9c74a5bd14("usb: dwc3: gadget: Free gadget structure
only after freeing endpoints"). |
| In the Linux kernel, the following vulnerability has been resolved:
firmware: meson_sm: fix to avoid potential NULL pointer dereference
of_match_device() may fail and returns a NULL pointer.
Fix this by checking the return value of of_match_device. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: Fix system crash due to lack of free space in LFS
When f2fs tries to checkpoint during foreground gc in LFS mode, system
crash occurs due to lack of free space if the amount of dirty node and
dentry pages generated by data migration exceeds free space.
The reproduction sequence is as follows.
- 20GiB capacity block device (null_blk)
- format and mount with LFS mode
- create a file and write 20,000MiB
- 4k random write on full range of the file
RIP: 0010:new_curseg+0x48a/0x510 [f2fs]
Code: 55 e7 f5 89 c0 48 0f af c3 48 8b 5d c0 48 c1 e8 20 83 c0 01 89 43 6c 48 83 c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc <0f> 0b f0 41 80 4f 48 04 45 85 f6 0f 84 ba fd ff ff e9 ef fe ff ff
RSP: 0018:ffff977bc397b218 EFLAGS: 00010246
RAX: 00000000000027b9 RBX: 0000000000000000 RCX: 00000000000027c0
RDX: 0000000000000000 RSI: 00000000000027b9 RDI: ffff8c25ab4e74f8
RBP: ffff977bc397b268 R08: 00000000000027b9 R09: ffff8c29e4a34b40
R10: 0000000000000001 R11: ffff977bc397b0d8 R12: 0000000000000000
R13: ffff8c25b4dd81a0 R14: 0000000000000000 R15: ffff8c2f667f9000
FS: 0000000000000000(0000) GS:ffff8c344ec80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00055d000 CR3: 0000000e30810003 CR4: 00000000003706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
allocate_segment_by_default+0x9c/0x110 [f2fs]
f2fs_allocate_data_block+0x243/0xa30 [f2fs]
? __mod_lruvec_page_state+0xa0/0x150
do_write_page+0x80/0x160 [f2fs]
f2fs_do_write_node_page+0x32/0x50 [f2fs]
__write_node_page+0x339/0x730 [f2fs]
f2fs_sync_node_pages+0x5a6/0x780 [f2fs]
block_operations+0x257/0x340 [f2fs]
f2fs_write_checkpoint+0x102/0x1050 [f2fs]
f2fs_gc+0x27c/0x630 [f2fs]
? folio_mark_dirty+0x36/0x70
f2fs_balance_fs+0x16f/0x180 [f2fs]
This patch adds checking whether free sections are enough before checkpoint
during gc.
[Jaegeuk Kim: code clean-up] |
