| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
platform/x86: lenovo-wmi-helpers: Fix memory leak in lwmi_dev_evaluate_int()
lwmi_dev_evaluate_int() leaks output.pointer when retval == NULL (found
by sashiko.dev [1]).
Fix it by moving `ret_obj = output.pointer' outside of the `if (retval)'
block so that it is always freed by the __free cleanup callback.
No functional change intended. |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: rsnd: Fix potential out-of-bounds access of component_dais[]
component_dais[RSND_MAX_COMPONENT] is initially zero-initialized
and later populated in rsnd_dai_of_node(). However, the existing boundary check:
if (i >= RSND_MAX_COMPONENT)
does not guarantee that the last valid element remains zero. As a result,
the loop can rely on component_dais[RSND_MAX_COMPONENT] being zero,
which may lead to an out-of-bounds access.
Found by Linux Verification Center (linuxtesting.org) with SVACE. |
| In the Linux kernel, the following vulnerability has been resolved:
apparmor: fix use-after-free in rawdata dedup loop
aa_replace_profiles() walks ns->rawdata_list to dedup the incoming
policy blob against entries already attached to existing profiles.
Per the kernel-doc on struct aa_loaddata, list membership does not
hold a reference: profiles hold pcount, and when the last pcount
drops, do_ploaddata_rmfs() is queued on a workqueue that takes
ns->lock and removes the entry. Between dropping the last pcount
and the workqueue running, an entry remains on the list with
pcount == 0.
aa_get_profile_loaddata() is an unconditional kref_get() on
pcount, so when the dedup loop hits such an entry, refcount
hardening reports
refcount_t: addition on 0; use-after-free.
inside aa_replace_profiles(), and the poisoned counter then
trips "saturated" and "underflow" warnings on the subsequent
uses of the same loaddata.
Before commit a0b7091c4de4 ("apparmor: fix race on rawdata
dereference") the dedup path used a get_unless_zero-style helper
on a single counter, so the existing "if (tmp)" guard was
meaningful. The split-refcount refactor introduced
aa_get_profile_loaddata(), which has plain kref_get() semantics,
and the guard quietly became a no-op.
Introduce aa_get_profile_loaddata_not0(), matching the existing
_not0 convention used by aa_get_profile_not0(), and use it for
the rawdata_list dedup lookup so dying entries are skipped.
Reproduced on x86_64 with v7.1-rc5 in QEMU+KVM running Ubuntu
24.04 + stress-ng 0.17.06:
stress-ng --apparmor 1 --klog-check --timeout 60s
Without this patch the three refcount_t warnings fire within a
few seconds. With it the same 60 s run is clean. Coverage is a
smoke-test only; a longer soak with CONFIG_KASAN, CONFIG_KCSAN
and CONFIG_PROVE_LOCKING would be welcome from anyone with the
cycles. |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix possible infinite loop in rt6_fill_node()
Sashiko reported this issue [1]. Apply the same fix as
commit f8d8ce1b515a ("ipv6: fix possible infinite loop in fib6_info_uses_dev()").
Writers holding tb6_lock can list_del_rcu(&rt->fib6_siblings)
without waiting for RCU readers; rt->fib6_siblings.next then still
points into the old ring and this softirq-side walker never reaches
&rt->fib6_siblings, causing a CPU stall. fib6_del_route() always
WRITE_ONCE()s rt->fib6_nsiblings to 0 before list_del_rcu(), so an
inside-loop check is a reliable detach signal.
[1] https://sashiko.dev/#/patchset/20260526020227.4857-1-jiayuan.chen%40linux.dev |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: composite: fix integer underflow in WebUSB GET_URL handling
The WebUSB GET_URL handler in composite_setup() narrows
landing_page_length to fit the host-supplied wLength using
landing_page_length = w_length
- WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH + landing_page_offset;
If wLength is smaller than WEBUSB_URL_DESCRIPTOR_HEADER_LENGTH the
unsigned subtraction wraps, and the subsequent
memcpy(url_descriptor->URL,
cdev->landing_page + landing_page_offset,
landing_page_length - landing_page_offset);
ends up copying close to UINT_MAX bytes from cdev->landing_page into
cdev->req->buf. KASAN reports a slab-out-of-bounds in composite_setup
on the kmalloc-2k gadget_info allocation, and FORTIFY_SOURCE traps the
memcpy as a 4294967293-byte field-spanning write into
url_descriptor->URL (size 252).
A USB host can reach this from a single SETUP packet against any
gadget that has webusb/use=1 and a landingPage configured.
Handle the small-wLength case before the math: when the host requested
fewer bytes than the URL descriptor header, only the header is
meaningful and no URL bytes need to be copied. Setting
landing_page_length to landing_page_offset makes the existing memcpy a
no-op and leaves the descriptor returned to the host unchanged for all
larger wLength values. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close
Since hci_dev_close_sync() can now be called during the reset path, we
should also set HCI_CMD_DRAIN_WORKQUEUE. This avoids queuing timeouts
while the hdev workqueue is being drained. |
| In the Linux kernel, the following vulnerability has been resolved:
fbdev: fix use-after-free in store_modes()
store_modes() replaces a framebuffer's modelist with modes from userspace.
On success it frees the old modelist with fb_destroy_modelist(). Two
fields still point into that freed list.
One pointer is fb_display[i].mode, the mode a console is using.
fbcon_new_modelist() moves these pointers to the new list. It only does so
for consoles still mapped to the framebuffer. An unmapped console is
skipped and keeps its stale pointer. Unbinding fbcon, for example, sets
con2fb_map[i] to -1 but leaves fb_display[i].mode set. An
FBIOPUT_VSCREENINFO ioctl with FB_ACTIVATE_INV_MODE later reaches
fbcon_mode_deleted(). That function reads the stale fb_display[i].mode
through fb_mode_is_equal(). The read is a use-after-free.
The other pointer is fb_info->mode, the current mode. It is set through
the mode sysfs attribute. store_modes() does not update fb_info->mode, so
it is left pointing into the freed list. show_mode(), the attribute's read
handler, dereferences the stale fb_info->mode through mode_string(). The
read is a use-after-free.
Clear both pointers before freeing the list. Commit a1f305893074 ("fbcon:
Set fb_display[i]->mode to NULL when the mode is released") added the
helper fbcon_delete_modelist(). It clears every fb_display[i].mode that
points into a given list. So far it is called only from the unregister
path. Call it from store_modes() too, and set fb_info->mode to NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: fix warning when unbinding
If there is an error during some initialization related to firmware,
the buffers dp->tx_ring[i].tx_status are released.
However this is released again when the device is unbinded (ath11k_pci),
and we get:
WARNING: CPU: 0 PID: 6231 at mm/slub.c:4368 free_large_kmalloc+0x57/0x90
Call Trace:
free_large_kmalloc
ath11k_dp_free
ath11k_core_deinit
ath11k_pci_remove
...
The issue is always reproducible from a VM because the MSI addressing
initialization is failing.
In order to fix the issue, just set the buffers to NULL after releasing in
order to avoid the double free. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw88: usb: fix memory leaks on USB write failures
When rtw_usb_write_port() fails to submit a USB Request Block (URB)
(e.g., due to device disconnect or ENOMEM), the completion callback is
never executed.
Currently, the driver ignores the return value of rtw_usb_write_port()
in rtw_usb_write_data() and rtw_usb_tx_agg_skb(). Because these
functions rely on the completion callback to free the socket buffers
(skbs) and the transaction control block (txcb), a submission failure
results in:
1. A memory leak of the allocated skb in rtw_usb_write_data().
2. A memory leak of the txcb structure and all aggregated skbs in
rtw_usb_tx_agg_skb().
Fix this by checking the return value of rtw_usb_write_port(). If it
fails, explicitly free the skb in rtw_usb_write_data(), and properly
purge the tx_ack_queue and free the txcb in rtw_usb_tx_agg_skb().
The issue was discovered in practice during device disconnect/reconnect
scenarios and memory pressure conditions. Tested by verifying normal TX
operation continues after the fix without regressions. |
| In the Linux kernel, the following vulnerability has been resolved:
xen-netback: Zero out sring pointers on unmap
If xenvif_map_frontend_data_rings() fails when a ring is already mapped,
it unmaps them via xenvif_unmap_frontend_data_rings() which keeps the
ring pointers unchanged. xenvif_connect_data()'s cleanup path calls
xenvif_disconnect_queue() which in turn calls
xenvif_unmap_frontend_data_rings() again, which will attempt to unmap the
pointers a second time.
Zero out the ring pointers after they are unmapped to avoid this issue.
This is XSA-532 |
| In the Linux kernel, the following vulnerability has been resolved:
xen-netback: Fix XenBus connection failure cleanup
xenvif_get_stats and xenvif_get_ethtool_stats capture vif->num_queues
under rcu_read_lock. We need to unpublish vif->num_queues before
synchronize_net to ensure that readers that come afterwards will not
read a non-zero vif->num_queues and attempt to access invalid queues.
This is the same cleanup algorithm as used in backend_disconnect and
added in commit b17075d5c198 ("xen-netback: fix race condition on XenBus
disconnect").
This is XSA-531 |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: validate compress cache inode only when enabled
F2FS_COMPRESS_INO() uses NM_I(sbi)->max_nid as the synthetic inode
number for the compressed page cache inode. That inode only exists when
the compress_cache mount option is enabled.
When compress_cache is disabled, max_nid is outside the valid inode
range. A corrupted directory entry that points to ino == max_nid should
therefore be rejected by f2fs_check_nid_range(). However, is_meta_ino()
currently treats F2FS_COMPRESS_INO() as a meta inode unconditionally,
so f2fs_iget() bypasses do_read_inode() and its nid range check, and
instantiates a fake internal inode instead.
Gate the compressed cache inode case on COMPRESS_CACHE, matching
f2fs_init_compress_inode(). With compress_cache disabled, ino ==
max_nid now follows the normal inode path and is rejected as an
out-of-range nid. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: atomic: fix UAF issue on f2fs_inode_info.atomic_inode
- ioctl(F2FS_IOC_GARBAGE_COLLECT_RANGE) - shrink
- f2fs_gc
- gc_data_segment
- ra_data_block(cow_inode)
- mapping = F2FS_I(inode)->atomic_inode->i_mapping
: f2fs_is_cow_file(cow_inode) is true
- f2fs_evict_inode(atomic_inode)
- clear_inode_flag(fi->cow_inode, FI_COW_FILE)
- F2FS_I(fi->cow_inode)->atomic_inode = NULL
...
- truncate_inode_pages_final(atomic_inode)
- f2fs_grab_cache_folio(mapping)
: create folio in atomic_inode->mapping
- clear_inode(atomic_inode)
- BUG_ON(atomic_inode->i_data.nrpages)
We need to add a reference on fi->atomic_inode before using its mapping
field during garbage collection, otherwise, it will cause UAF issue. |
| In the Linux kernel, the following vulnerability has been resolved:
Revert "f2fs: remove non-uptodate folio from the page cache in move_data_block"
This reverts commit 9609dd704725a40cd63d915f2ab6c44248a44598.
The kernel panics are keeping to be reported especially when the f2fs
partition get almost full. By investigation, we find that the reason is
one f2fs page got freed to buddy without being deleted from LRU and the
root cause is the race happened in [2] which is enrolled by this commit.
There are 3 race processes in this scenario, please find below for their
main activities.
The changed code in move_data_block() lets the GC path evict the tail-end
folio from the page cache through folio_end_dropbehind(). Once
folio_unmap_invalidate() removes the folio from mapping->i_pages, the
page-cache references for all pages in the folio are dropped. The folio
is then kept alive only by temporary external references, which allows a
later split to operate on a folio whose subpages are no longer protected
by page-cache references.
After the page-cache references are gone, split_folio_to_order() can
split the big folio into individual pages and put the resulting subpages
back on the LRU. For tail pages beyond EOF, split removes them from the
page cache and drops their page-cache references. A tail page can then
remain on the LRU with PG_lru set while holding only the split caller's
temporary reference. When free_folio_and_swap_cache() drops that final
reference, the page enters the final folio_put() release path.
In parallel, folio_isolate_lru() can observe the same tail page with a
non-zero refcount and PG_lru set. It clears PG_lru before taking its own
reference. If this races with the final folio_put() from the split path,
__folio_put() sees PG_lru already cleared and skips lruvec_del_folio().
The page is then freed back to the allocator while its lru links are
still present in the LRU list. A later LRU operation on a neighboring
page detects the stale link and reports list corruption.
[1]
[ 22.486082] list_del corruption. next->prev should be fffffffec10e0ac8, but was dead000000000122. (next=fffffffec10e0a88)
[ 22.486130] ------------[ cut here ]------------
[ 22.486134] kernel BUG at lib/list_debug.c:67!
[ 22.486141] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
[ 22.488502] Tainted: [W]=WARN, [O]=OOT_MODULE
[ 22.488506] Hardware name: Spreadtrum UMS9230 1H10 SoC (DT)
[ 22.488511] pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 22.488517] pc : __list_del_entry_valid_or_report+0x14c/0x154
[ 22.488531] lr : __list_del_entry_valid_or_report+0x14c/0x154
[ 22.488539] sp : ffffffc08006b830
[ 22.488542] x29: ffffffc08006b868 x28: 0000000000003020 x27: 0000000000000000
[ 22.488553] x26: 0000000000000000 x25: 0000000000000004 x24: fffffffec10e0ac0
[ 22.488564] x23: 00000000000000e8 x22: 0000000000000024 x21: dead000000000122
[ 22.488574] x20: fffffffec10e0a88 x19: fffffffec10e0ac8 x18: ffffffc080061060
[ 22.488585] x17: 20747562202c3863 x16: 6130653031636566 x15: 0000000000000058
[ 22.488595] x14: 0000000000000004 x13: ffffff80f91e0000 x12: 0000000000000003
[ 22.488605] x11: 0000000000000003 x10: 0000000000000001 x9 : ffe85721f0e25f00
[ 22.488615] x8 : ffe85721f0e25f00 x7 : 0000000000000000 x6 : 6c65645f7473696c
[ 22.488625] x5 : ffffffed39b23026 x4 : 0000000000000000 x3 : 0000000000000010
[ 22.488636] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 000000000000006d
[ 22.488647] Call trace:
[ 22.488651] __list_del_entry_valid_or_report+0x14c/0x154 (P)
[ 22.488661] __folio_put+0x2bc/0x434
[ 22.488670] folio_put+0x28/0x58
[ 22.488678] do_garbage_collect+0x1a34/0x2584
[ 22.488689] f2fs_gc+0x230/0x9b4
[ 22.488697] f2fs_fallocate+0xb90/0xdf4
[ 22.488706] vfs_fallocate+0x1b4/0x2bc
[ 22.488716] __arm64_sys_fallocate+0x44/0x78
[ 22.488725] invoke_syscall+0x58/0xe4
[ 22.488732] do_el0_svc+0x48/0xdc
[ 22.488739] el0
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix incorrect FI_NO_EXTENT handling in __destroy_extent_node()
When __destroy_extent_node() sets the inode flag FI_NO_EXTENT, it does
not reset the length of the largest extent to 0 and update the inode
folio. Since modifications to the extent tree are disallowed afterward,
the cached largest extent may become stale. This can trigger the
following error in xfstests generic/388:
F2FS-fs (dm-0): sanity_check_extent_cache: inode (ino=1761) extent info [220057, 57, 6] is incorrect, run fsck to fix
In the f2fs_drop_inode path, __destroy_extent_node() does not need to
guarantee that et->node_cnt is 0, because concurrency with writeback
is expected in this path, and writeback may update the extent cache.
This patch reverts commit ed78aeebef05 ("f2fs: fix node_cnt race between
extent node destroy and writeback"), and remove the unnecessary zero
check of et->node_cnt. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: read COW data with the original inode during atomic write
When updating an atomic-write file, f2fs_write_begin() may read the
previously written data back from the COW inode:
prepare_atomic_write_begin() locates the block in the COW inode and sets
use_cow, and the read bio is then built with the COW inode:
f2fs_submit_page_read(use_cow ? F2FS_I(inode)->cow_inode : inode,
...);
and f2fs_grab_read_bio() decides whether to schedule fs-layer decryption
(STEP_DECRYPT) for the bio based on that inode via
fscrypt_inode_uses_fs_layer_crypto().
However, the folio being filled belongs to the original inode
(folio->mapping->host == inode), and the data stored in the COW block was
encrypted (or left as plaintext) using the original inode's context, not
the COW inode's -- see f2fs_encrypt_one_page(), which keys off
fio->page->mapping->host. fscrypt_decrypt_pagecache_blocks() likewise
operates on folio->mapping->host.
The COW inode is created as a tmpfile in the parent directory and inherits
its encryption policy from there. With test_dummy_encryption the newly
created COW inode gets the dummy policy and becomes encrypted, while a
pre-existing regular file -- created before the policy applied, e.g.
already present in the on-disk image -- stays unencrypted. The read
path then sets STEP_DECRYPT based on the encrypted COW inode and calls
fscrypt_decrypt_pagecache_blocks() on a folio whose host (the unencrypted
original inode) has a NULL ->i_crypt_info, dereferencing it:
Oops: general protection fault, probably for non-canonical address ...
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
RIP: 0010:fscrypt_decrypt_pagecache_blocks+0xa0/0x310
Workqueue: f2fs_post_read_wq f2fs_post_read_work
Call Trace:
fscrypt_decrypt_bio+0x1eb/0x340
f2fs_post_read_work+0xba/0x140
process_one_work+0x91c/0x1a40
worker_thread+0x677/0xe90
kthread+0x2bc/0x3a0
The COW inode is only needed to locate the on-disk block, and that block
address is already resolved into @blkaddr by prepare_atomic_write_begin()
via __find_data_block(cow_inode, ...); f2fs_submit_page_read() then reads
from that physical @blkaddr directly, so the inode argument only selects
the post-read crypto context, not which block is fetched. Reading with
@inode therefore returns the same (latest, not-yet-committed) COW data,
while making both the fs-layer decryption decision and the inline crypto
path use the correct (original inode's) key.
With the COW inode no longer used at the read site, the use_cow flag has no
remaining consumer; drop it from f2fs_write_begin() and
prepare_atomic_write_begin(). |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_byteorder: remove multi-register support
64bit byteorder conversion is broken when several registers need to be
converted because the source register array advances in steps for 4 bytes
instead of 8:
for (i = ...
src64 = nft_reg_load64(&src[i]);
~~~~~ u32 *src
nft_reg_store64(&dst64[i],
Remove the multi-register support, it has other issues as well:
Pablo points out that commit
caf3ef7468f7 ("netfilter: nf_tables: prevent OOB access in nft_byteorder_eval")
alters semantics: before the loop operated on registers, i.e.
for ( ... )
dst32[i] = htons((u16)src32[i])
.. but after the patch it will operate on bytes, which makes this
useless to convert e.g. concatenations, which store each compound
in its own register.
Multi-convert of u32 has one theoretical application:
ct mark . meta mark . tcp dport @intervalset
Because ct mark and meta mark are host byte order, use with
intervals has to convert the byteorder for ct/meta mark value
to network byte order (bigendian).
nftables emits this:
[ meta load mark => reg 1 ]
[ byteorder reg 1 = hton(reg 1, 4, 4) ]
[ ct load mark => reg 9 ]
[ byteorder reg 9 = hton(reg 9, 4, 4) ]
...
I.e. two separate calls. Theoretically it could be changed to do:
[ meta load mark => reg 1 ]
[ ct load mark => reg 9 ]
[ byteorder reg 1 = htonl(reg 1, 4, 8) ]
...
But then all it would take to change the set to
meta mark . tcp dport . ct mark
... and we'd be back to two "byteorder" calls. IOW, support to
convert a range of registers is both dysfunctional and dubious.
Simplify this: remove the feature.
Pablo Neira Ayuso points out that nftables before 1.1.0 can generate
incorrect byteorder conversions, see 9fe58952c45a,
"evaluate: skip byteorder conversion for selector smaller than 2 bytes"
in nftables.git). Affected rulesets fail to load with this change and
old userspace due to 'len != size' check. |
| In the Linux kernel, the following vulnerability has been resolved:
net: skbuff: propagate shared-frag marker in skb_zerocopy()
skb_zerocopy() moves frag descriptors from @from into @to and takes a
reference on each frag, but it does not copy skb_shinfo(from)->flags into
skb_shinfo(to)->flags. A destination skb holding the same page-cache
backed frags as the source therefore reports skb_has_shared_frag() as
false.
That breaks the invariant relied on by later in-place writers. ESP input
checks skb_has_shared_frag() before deciding whether an uncloned
nonlinear skb can skip skb_cow_data(); with the marker lost, an skb that
skb_zerocopy() built for nfnetlink_queue or for an openvswitch upcall is
decrypted in place, letting an unprivileged user write into the page
cache of a root-owned read-only file.
Propagate SKBFL_SHARED_FRAG when frag descriptors are copied, as done for
the other frag-transfer helpers. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: tcp: use UNACK timeout for non-closing RST packets
Commit be0502a3f2e9 ("netfilter: conntrack: tcp: only close if RST
matches exact sequence") keeps an established conntrack entry in
ESTABLISHED when an in-window RST does not match the expected sequence
number exactly, so the endpoint can validate the RST with a challenge
ACK.
The timeout selection nevertheless uses the CLOSE timeout for every RST
packet. The bug is that timeout selection is based on the packet type,
not on the state transition result: even when RST validation keeps
new_state in ESTABLISHED, the timeout is still forced to
TCP_CONNTRACK_CLOSE.
Linux TCP independently rate limits challenge ACKs per socket. A second
non-exact RST can therefore arrive after the first challenge ACK has
restored the timeout but before the rate limit expires. The second RST
lowers the timeout to 10 seconds again while the endpoint suppresses the
second challenge ACK, allowing the conntrack entry to expire while both
TCP endpoints remain established.
Using the ESTABLISHED timeout for such RSTs would avoid this short
expiration window, but it could also retain stale entries for the
five-day default because conntrack cannot reliably match the endpoint's
exact TCP state.
Use the UNACK timeout for RST packets that leave the conntrack entry in
TCP_CONNTRACK_ESTABLISHED. Exact-match RSTs and accepted RST packet
trains still fall through to timeouts[new_state], which preserves the
CLOSE timeout when conntrack accepts the RST as closing the flow.
This avoids the aggressive 10-second expiration window for non-exact
RSTs while preserving the short timeout for RSTs that conntrack accepts
as closing the flow. |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_teql: fix use-after-free on lower qdisc drop
The issue: teql_master_xmit() tests the slave's ndo_start_xmit() return
value against NETDEV_TX_OK alone. A slave that consumes the skb but
returns an error code (rc < NET_XMIT_MASK, e.g. NET_XMIT_DROP) is treated
as if the skb were still owned, so the loop restores skb->dev and calls
__skb_pull() on it. A VLAN slave returns the result of dev_queue_xmit()
from its ndo_start_xmit() (propagated since cbbef5e18307), and when the
lower qdisc drops the packet that value is NET_XMIT_DROP after the skb
has been freed, giving a use-after-free in teql_master_xmit().
The Fix: test for consumption with dev_xmit_complete(), which accepts
NETDEV_TX_OK and every rc < NET_XMIT_MASK, matching other callers that
need to distinguish consumed results from busy. Only NETDEV_TX_OK keeps
the packet counted in tx_packets/tx_bytes and advances the slave; a
consumed result that is neither a success nor NET_XMIT_CN ends the
attempt and is charged to tx_dropped, so lower-qdisc drops are no longer
reported as good transmits. NET_XMIT_CN is counted like success because
it can accompany acceptance of the current packet: pfifo_head_drop drops
the old head, enqueues the current skb and returns NET_XMIT_CN.
Conditions to recreate the bug:
With CONFIG_NET_SCH_TEQL,
CONFIG_VLAN_8021Q and CONFIG_DUMMY enabled, add lkrdummy0 (dummy) and
lkrvlan0 (VLAN id 37 on lkrdummy0); set a pfifo limit 0 root on lkrdummy0
and a teql0 root on lkrvlan0; bring teql0 up with an address and send one
UDP packet to it. The VLAN xmit returns NET_XMIT_DROP from the lower
qdisc while holding a freed skb. |
