In the Linux kernel, the following vulnerability has been resolved:
x86/kexec: Fix double-free of elf header buffer
After
b3e34a47f989 ("x86/kexec: fix memory leak of elf header buffer"),
freeing image->elf_headers in the error path of crash_load_segments()
is not needed because kimage_file_post_load_cleanup() will take
care of that later. And not clearing it could result in a double-free.
Drop the superfluous vfree() call at the error path of
crash_load_segments().
In the Linux kernel, the following vulnerability has been resolved:
bpf: drop unnecessary user-triggerable WARN_ONCE in verifierl log
It's trivial for user to trigger "verifier log line truncated" warning,
as verifier has a fixed-sized buffer of 1024 bytes (as of now), and there are at
least two pieces of user-provided information that can be output through
this buffer, and both can be arbitrarily sized by user:
- BTF names;
- BTF.ext source code lines strings.
Verifier log buffer should be properly sized for typical verifier state
output. But it's sort-of expected that this buffer won't be long enough
in some circumstances. So let's drop the check. In any case code will
work correctly, at worst truncating a part of a single line output.
In the Linux kernel, the following vulnerability has been resolved:
media: mediatek: vcodec: fix resource leaks in vdec_msg_queue_init()
If we encounter any error in the vdec_msg_queue_init() then we need
to set "msg_queue->wdma_addr.size = 0;". Normally, this is done
inside the vdec_msg_queue_deinit() function. However, if the
first call to allocate &msg_queue->wdma_addr fails, then the
vdec_msg_queue_deinit() function is a no-op. For that situation, just
set the size to zero explicitly and return.
There were two other error paths which did not clean up before returning.
Change those error paths to goto mem_alloc_err.
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: Add missing hw_ops->get_ring_selector() for IPQ5018
During sending data after clients connected, hw_ops->get_ring_selector()
will be called. But for IPQ5018, this member isn't set, and the
following NULL pointer exception will be occurred:
[ 38.840478] 8<--- cut here ---
[ 38.840517] Unable to handle kernel NULL pointer dereference at virtual address 00000000
...
[ 38.923161] PC is at 0x0
[ 38.927930] LR is at ath11k_dp_tx+0x70/0x730 [ath11k]
...
[ 39.063264] Process hostapd (pid: 1034, stack limit = 0x801ceb3d)
[ 39.068994] Stack: (0x856a9a68 to 0x856aa000)
...
[ 39.438467] [<7f323804>] (ath11k_dp_tx [ath11k]) from [<7f314e6c>] (ath11k_mac_op_tx+0x80/0x190 [ath11k])
[ 39.446607] [<7f314e6c>] (ath11k_mac_op_tx [ath11k]) from [<7f17dbe0>] (ieee80211_handle_wake_tx_queue+0x7c/0xc0 [mac80211])
[ 39.456162] [<7f17dbe0>] (ieee80211_handle_wake_tx_queue [mac80211]) from [<7f174450>] (ieee80211_probereq_get+0x584/0x704 [mac80211])
[ 39.467443] [<7f174450>] (ieee80211_probereq_get [mac80211]) from [<7f178c40>] (ieee80211_tx_prepare_skb+0x1f8/0x248 [mac80211])
[ 39.479334] [<7f178c40>] (ieee80211_tx_prepare_skb [mac80211]) from [<7f179e28>] (__ieee80211_subif_start_xmit+0x32c/0x3d4 [mac80211])
[ 39.491053] [<7f179e28>] (__ieee80211_subif_start_xmit [mac80211]) from [<7f17af08>] (ieee80211_tx_control_port+0x19c/0x288 [mac80211])
[ 39.502946] [<7f17af08>] (ieee80211_tx_control_port [mac80211]) from [<7f0fc704>] (nl80211_tx_control_port+0x174/0x1d4 [cfg80211])
[ 39.515017] [<7f0fc704>] (nl80211_tx_control_port [cfg80211]) from [<808ceac4>] (genl_rcv_msg+0x154/0x340)
[ 39.526814] [<808ceac4>] (genl_rcv_msg) from [<808cdb74>] (netlink_rcv_skb+0xb8/0x11c)
[ 39.536446] [<808cdb74>] (netlink_rcv_skb) from [<808ce1d0>] (genl_rcv+0x28/0x34)
[ 39.544344] [<808ce1d0>] (genl_rcv) from [<808cd234>] (netlink_unicast+0x174/0x274)
[ 39.551895] [<808cd234>] (netlink_unicast) from [<808cd510>] (netlink_sendmsg+0x1dc/0x440)
[ 39.559362] [<808cd510>] (netlink_sendmsg) from [<808596e0>] (____sys_sendmsg+0x1a8/0x1fc)
[ 39.567697] [<808596e0>] (____sys_sendmsg) from [<8085b1a8>] (___sys_sendmsg+0xa4/0xdc)
[ 39.575941] [<8085b1a8>] (___sys_sendmsg) from [<8085b310>] (sys_sendmsg+0x44/0x74)
[ 39.583841] [<8085b310>] (sys_sendmsg) from [<80300060>] (ret_fast_syscall+0x0/0x40)
...
[ 39.620734] Code: bad PC value
[ 39.625869] ---[ end trace 8aef983ad3cbc032 ]---
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix WARNING in mark_buffer_dirty due to discarded buffer reuse
A syzbot stress test using a corrupted disk image reported that
mark_buffer_dirty() called from __nilfs_mark_inode_dirty() or
nilfs_palloc_commit_alloc_entry() may output a kernel warning, and can
panic if the kernel is booted with panic_on_warn.
This is because nilfs2 keeps buffer pointers in local structures for some
metadata and reuses them, but such buffers may be forcibly discarded by
nilfs_clear_dirty_page() in some critical situations.
This issue is reported to appear after commit 28a65b49eb53 ("nilfs2: do
not write dirty data after degenerating to read-only"), but the issue has
potentially existed before.
Fix this issue by checking the uptodate flag when attempting to reuse an
internally held buffer, and reloading the metadata instead of reusing the
buffer if the flag was lost.
In the Linux kernel, the following vulnerability has been resolved:
tracing/user_events: Ensure write index cannot be negative
The write index indicates which event the data is for and accesses a
per-file array. The index is passed by user processes during write()
calls as the first 4 bytes. Ensure that it cannot be negative by
returning -EINVAL to prevent out of bounds accesses.
Update ftrace self-test to ensure this occurs properly.
In the Linux kernel, the following vulnerability has been resolved:
drm/msm: fix NULL-deref on irq uninstall
In case of early initialisation errors and on platforms that do not use
the DPU controller, the deinitilisation code can be called with the kms
pointer set to NULL.
Patchwork: https://patchwork.freedesktop.org/patch/525104/
In the Linux kernel, the following vulnerability has been resolved:
vfio/type1: fix cap_migration information leak
Fix an information leak where an uninitialized hole in struct
vfio_iommu_type1_info_cap_migration on the stack is exposed to userspace.
The definition of struct vfio_iommu_type1_info_cap_migration contains a hole as
shown in this pahole(1) output:
struct vfio_iommu_type1_info_cap_migration {
struct vfio_info_cap_header header; /* 0 8 */
__u32 flags; /* 8 4 */
/* XXX 4 bytes hole, try to pack */
__u64 pgsize_bitmap; /* 16 8 */
__u64 max_dirty_bitmap_size; /* 24 8 */
/* size: 32, cachelines: 1, members: 4 */
/* sum members: 28, holes: 1, sum holes: 4 */
/* last cacheline: 32 bytes */
};
The cap_mig variable is filled in without initializing the hole:
static int vfio_iommu_migration_build_caps(struct vfio_iommu *iommu,
struct vfio_info_cap *caps)
{
struct vfio_iommu_type1_info_cap_migration cap_mig;
cap_mig.header.id = VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION;
cap_mig.header.version = 1;
cap_mig.flags = 0;
/* support minimum pgsize */
cap_mig.pgsize_bitmap = (size_t)1 << __ffs(iommu->pgsize_bitmap);
cap_mig.max_dirty_bitmap_size = DIRTY_BITMAP_SIZE_MAX;
return vfio_info_add_capability(caps, &cap_mig.header, sizeof(cap_mig));
}
The structure is then copied to a temporary location on the heap. At this point
it's already too late and ioctl(VFIO_IOMMU_GET_INFO) copies it to userspace
later:
int vfio_info_add_capability(struct vfio_info_cap *caps,
struct vfio_info_cap_header *cap, size_t size)
{
struct vfio_info_cap_header *header;
header = vfio_info_cap_add(caps, size, cap->id, cap->version);
if (IS_ERR(header))
return PTR_ERR(header);
memcpy(header + 1, cap + 1, size - sizeof(*header));
return 0;
}
This issue was found by code inspection.
In the Linux kernel, the following vulnerability has been resolved:
serial: sprd: Fix DMA buffer leak issue
Release DMA buffer when _probe() returns failure to avoid memory leak.
In the Linux kernel, the following vulnerability has been resolved:
maple_tree: fix potential out-of-bounds access in mas_wr_end_piv()
Check the write offset end bounds before using it as the offset into the
pivot array. This avoids a possible out-of-bounds access on the pivot
array if the write extends to the last slot in the node, in which case the
node maximum should be used as the end pivot.
akpm: this doesn't affect any current callers, but new users of mapletree
may encounter this problem if backported into earlier kernels, so let's
fix it in -stable kernels in case of this.
In the Linux kernel, the following vulnerability has been resolved:
autofs: fix memory leak of waitqueues in autofs_catatonic_mode
Syzkaller reports a memory leak:
BUG: memory leak
unreferenced object 0xffff88810b279e00 (size 96):
comm "syz-executor399", pid 3631, jiffies 4294964921 (age 23.870s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 08 9e 27 0b 81 88 ff ff ..........'.....
08 9e 27 0b 81 88 ff ff 00 00 00 00 00 00 00 00 ..'.............
backtrace:
[<ffffffff814cfc90>] kmalloc_trace+0x20/0x90 mm/slab_common.c:1046
[<ffffffff81bb75ca>] kmalloc include/linux/slab.h:576 [inline]
[<ffffffff81bb75ca>] autofs_wait+0x3fa/0x9a0 fs/autofs/waitq.c:378
[<ffffffff81bb88a7>] autofs_do_expire_multi+0xa7/0x3e0 fs/autofs/expire.c:593
[<ffffffff81bb8c33>] autofs_expire_multi+0x53/0x80 fs/autofs/expire.c:619
[<ffffffff81bb6972>] autofs_root_ioctl_unlocked+0x322/0x3b0 fs/autofs/root.c:897
[<ffffffff81bb6a95>] autofs_root_ioctl+0x25/0x30 fs/autofs/root.c:910
[<ffffffff81602a9c>] vfs_ioctl fs/ioctl.c:51 [inline]
[<ffffffff81602a9c>] __do_sys_ioctl fs/ioctl.c:870 [inline]
[<ffffffff81602a9c>] __se_sys_ioctl fs/ioctl.c:856 [inline]
[<ffffffff81602a9c>] __x64_sys_ioctl+0xfc/0x140 fs/ioctl.c:856
[<ffffffff84608225>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff84608225>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff84800087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
autofs_wait_queue structs should be freed if their wait_ctr becomes zero.
Otherwise they will be lost.
In this case an AUTOFS_IOC_EXPIRE_MULTI ioctl is done, then a new
waitqueue struct is allocated in autofs_wait(), its initial wait_ctr
equals 2. After that wait_event_killable() is interrupted (it returns
-ERESTARTSYS), so that 'wq->name.name == NULL' condition may be not
satisfied. Actually, this condition can be satisfied when
autofs_wait_release() or autofs_catatonic_mode() is called and, what is
also important, wait_ctr is decremented in those places. Upon the exit of
autofs_wait(), wait_ctr is decremented to 1. Then the unmounting process
begins: kill_sb calls autofs_catatonic_mode(), which should have freed the
waitqueues, but it only decrements its usage counter to zero which is not
a correct behaviour.
edit:imk
This description is of course not correct. The umount performed as a result
of an expire is a umount of a mount that has been automounted, it's not the
autofs mount itself. They happen independently, usually after everything
mounted within the autofs file system has been expired away. If everything
hasn't been expired away the automount daemon can still exit leaving mounts
in place. But expires done in both cases will result in a notification that
calls autofs_wait_release() with a result status. The problem case is the
summary execution of of the automount daemon. In this case any waiting
processes won't be woken up until either they are terminated or the mount
is umounted.
end edit: imk
So in catatonic mode we should free waitqueues which counter becomes zero.
edit: imk
Initially I was concerned that the calling of autofs_wait_release() and
autofs_catatonic_mode() was not mutually exclusive but that can't be the
case (obviously) because the queue entry (or entries) is removed from the
list when either of these two functions are called. Consequently the wait
entry will be freed by only one of these functions or by the woken process
in autofs_wait() depending on the order of the calls.
end edit: imk
In the Linux kernel, the following vulnerability has been resolved:
nfp: clean mc addresses in application firmware when closing port
When moving devices from one namespace to another, mc addresses are
cleaned in software while not removed from application firmware. Thus
the mc addresses are remained and will cause resource leak.
Now use `__dev_mc_unsync` to clean mc addresses when closing port.
In the Linux kernel, the following vulnerability has been resolved:
erofs: stop parsing non-compact HEAD index if clusterofs is invalid
Syzbot generated a crafted image [1] with a non-compact HEAD index of
clusterofs 33024 while valid numbers should be 0 ~ lclustersize-1,
which causes the following unexpected behavior as below:
BUG: unable to handle page fault for address: fffff52101a3fff9
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 23ffed067 P4D 23ffed067 PUD 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 4398 Comm: kworker/u5:1 Not tainted 6.3.0-rc6-syzkaller-g09a9639e56c0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
Workqueue: erofs_worker z_erofs_decompressqueue_work
RIP: 0010:z_erofs_decompress_queue+0xb7e/0x2b40
...
Call Trace:
<TASK>
z_erofs_decompressqueue_work+0x99/0xe0
process_one_work+0x8f6/0x1170
worker_thread+0xa63/0x1210
kthread+0x270/0x300
ret_from_fork+0x1f/0x30
Note that normal images or images using compact indexes are not
impacted. Let's fix this now.
[1] https://lore.kernel.org/r/000000000000ec75b005ee97fbaa@google.com
In the Linux kernel, the following vulnerability has been resolved:
hfs/hfsplus: avoid WARN_ON() for sanity check, use proper error handling
Commit 55d1cbbbb29e ("hfs/hfsplus: use WARN_ON for sanity check") fixed
a build warning by turning a comment into a WARN_ON(), but it turns out
that syzbot then complains because it can trigger said warning with a
corrupted hfs image.
The warning actually does warn about a bad situation, but we are much
better off just handling it as the error it is. So rather than warn
about us doing bad things, stop doing the bad things and return -EIO.
While at it, also fix a memory leak that was introduced by an earlier
fix for a similar syzbot warning situation, and add a check for one case
that historically wasn't handled at all (ie neither comment nor
subsequent WARN_ON).
In the Linux kernel, the following vulnerability has been resolved:
octeontx2-af: Add validation for lmac type
Upon physical link change, firmware reports to the kernel about the
change along with the details like speed, lmac_type_id, etc.
Kernel derives lmac_type based on lmac_type_id received from firmware.
In a few scenarios, firmware returns an invalid lmac_type_id, which
is resulting in below kernel panic. This patch adds the missing
validation of the lmac_type_id field.
Internal error: Oops: 96000005 [#1] PREEMPT SMP
[ 35.321595] Modules linked in:
[ 35.328982] CPU: 0 PID: 31 Comm: kworker/0:1 Not tainted
5.4.210-g2e3169d8e1bc-dirty #17
[ 35.337014] Hardware name: Marvell CN103XX board (DT)
[ 35.344297] Workqueue: events work_for_cpu_fn
[ 35.352730] pstate: 40400089 (nZcv daIf +PAN -UAO)
[ 35.360267] pc : strncpy+0x10/0x30
[ 35.366595] lr : cgx_link_change_handler+0x90/0x180
In the Linux kernel, the following vulnerability has been resolved:
fs: drop peer group ids under namespace lock
When cleaning up peer group ids in the failure path we need to make sure
to hold on to the namespace lock. Otherwise another thread might just
turn the mount from a shared into a non-shared mount concurrently.
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to drop all dirty pages during umount() if cp_error is set
xfstest generic/361 reports a bug as below:
f2fs_bug_on(sbi, sbi->fsync_node_num);
kernel BUG at fs/f2fs/super.c:1627!
RIP: 0010:f2fs_put_super+0x3a8/0x3b0
Call Trace:
generic_shutdown_super+0x8c/0x1b0
kill_block_super+0x2b/0x60
kill_f2fs_super+0x87/0x110
deactivate_locked_super+0x39/0x80
deactivate_super+0x46/0x50
cleanup_mnt+0x109/0x170
__cleanup_mnt+0x16/0x20
task_work_run+0x65/0xa0
exit_to_user_mode_prepare+0x175/0x190
syscall_exit_to_user_mode+0x25/0x50
do_syscall_64+0x4c/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
During umount(), if cp_error is set, f2fs_wait_on_all_pages() should
not stop waiting all F2FS_WB_CP_DATA pages to be writebacked, otherwise,
fsync_node_num can be non-zero after f2fs_wait_on_all_pages() causing
this bug.
In this case, to avoid deadloop in f2fs_wait_on_all_pages(), it needs
to drop all dirty pages rather than redirtying them.
In the Linux kernel, the following vulnerability has been resolved:
md/raid10: fix memleak for 'conf->bio_split'
In the error path of raid10_run(), 'conf' need be freed, however,
'conf->bio_split' is missed and memory will be leaked.
Since there are 3 places to free 'conf', factor out a helper to fix the
problem.
In the Linux kernel, the following vulnerability has been resolved:
drm/msm/dpu: Add check for cstate
As kzalloc may fail and return NULL pointer,
it should be better to check cstate
in order to avoid the NULL pointer dereference
in __drm_atomic_helper_crtc_reset.
Patchwork: https://patchwork.freedesktop.org/patch/514163/
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix incorrect splitting in btrfs_drop_extent_map_range
In production we were seeing a variety of WARN_ON()'s in the extent_map
code, specifically in btrfs_drop_extent_map_range() when we have to call
add_extent_mapping() for our second split.
Consider the following extent map layout
PINNED
[0 16K) [32K, 48K)
and then we call btrfs_drop_extent_map_range for [0, 36K), with
skip_pinned == true. The initial loop will have
start = 0
end = 36K
len = 36K
we will find the [0, 16k) extent, but since we are pinned we will skip
it, which has this code
start = em_end;
if (end != (u64)-1)
len = start + len - em_end;
em_end here is 16K, so now the values are
start = 16K
len = 16K + 36K - 16K = 36K
len should instead be 20K. This is a problem when we find the next
extent at [32K, 48K), we need to split this extent to leave [36K, 48k),
however the code for the split looks like this
split->start = start + len;
split->len = em_end - (start + len);
In this case we have
em_end = 48K
split->start = 16K + 36K // this should be 16K + 20K
split->len = 48K - (16K + 36K) // this overflows as 16K + 36K is 52K
and now we have an invalid extent_map in the tree that potentially
overlaps other entries in the extent map. Even in the non-overlapping
case we will have split->start set improperly, which will cause problems
with any block related calculations.
We don't actually need len in this loop, we can simply use end as our
end point, and only adjust start up when we find a pinned extent we need
to skip.
Adjust the logic to do this, which keeps us from inserting an invalid
extent map.
We only skip_pinned in the relocation case, so this is relatively rare,
except in the case where you are running relocation a lot, which can
happen with auto relocation on.
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: Fix race condition in hidp_session_thread
There is a potential race condition in hidp_session_thread that may
lead to use-after-free. For instance, the timer is active while
hidp_del_timer is called in hidp_session_thread(). After hidp_session_put,
then 'session' will be freed, causing kernel panic when hidp_idle_timeout
is running.
The solution is to use del_timer_sync instead of del_timer.
Here is the call trace:
? hidp_session_probe+0x780/0x780
call_timer_fn+0x2d/0x1e0
__run_timers.part.0+0x569/0x940
hidp_session_probe+0x780/0x780
call_timer_fn+0x1e0/0x1e0
ktime_get+0x5c/0xf0
lapic_next_deadline+0x2c/0x40
clockevents_program_event+0x205/0x320
run_timer_softirq+0xa9/0x1b0
__do_softirq+0x1b9/0x641
__irq_exit_rcu+0xdc/0x190
irq_exit_rcu+0xe/0x20
sysvec_apic_timer_interrupt+0xa1/0xc0
In the Linux kernel, the following vulnerability has been resolved:
inotify: Avoid reporting event with invalid wd
When inotify_freeing_mark() races with inotify_handle_inode_event() it
can happen that inotify_handle_inode_event() sees that i_mark->wd got
already reset to -1 and reports this value to userspace which can
confuse the inotify listener. Avoid the problem by validating that wd is
sensible (and pretend the mark got removed before the event got
generated otherwise).
In the Linux kernel, the following vulnerability has been resolved:
serial: sc16is7xx: setup GPIO controller later in probe
The GPIO controller component of the sc16is7xx driver is setup too
early, which can result in a race condition where another device tries
to utilise the GPIO lines before the sc16is7xx device has finished
initialising.
This issue manifests itself as an Oops when the GPIO lines are configured:
Unable to handle kernel read from unreadable memory at virtual address
...
pc : sc16is7xx_gpio_direction_output+0x68/0x108 [sc16is7xx]
lr : sc16is7xx_gpio_direction_output+0x4c/0x108 [sc16is7xx]
...
Call trace:
sc16is7xx_gpio_direction_output+0x68/0x108 [sc16is7xx]
gpiod_direction_output_raw_commit+0x64/0x318
gpiod_direction_output+0xb0/0x170
create_gpio_led+0xec/0x198
gpio_led_probe+0x16c/0x4f0
platform_drv_probe+0x5c/0xb0
really_probe+0xe8/0x448
driver_probe_device+0xe8/0x138
__device_attach_driver+0x94/0x118
bus_for_each_drv+0x8c/0xe0
__device_attach+0x100/0x1b8
device_initial_probe+0x28/0x38
bus_probe_device+0xa4/0xb0
deferred_probe_work_func+0x90/0xe0
process_one_work+0x1c4/0x480
worker_thread+0x54/0x430
kthread+0x138/0x150
ret_from_fork+0x10/0x1c
This patch moves the setup of the GPIO controller functions to later in the
probe function, ensuring the sc16is7xx device has already finished
initialising by the time other devices try to make use of the GPIO lines.
The error handling has also been reordered to reflect the new
initialisation order.
In the Linux kernel, the following vulnerability has been resolved:
s390/dcssblk: fix kernel crash with list_add corruption
Commit fb08a1908cb1 ("dax: simplify the dax_device <-> gendisk
association") introduced new logic for gendisk association, requiring
drivers to explicitly call dax_add_host() and dax_remove_host().
For dcssblk driver, some dax_remove_host() calls were missing, e.g. in
device remove path. The commit also broke error handling for out_dax case
in device add path, resulting in an extra put_device() w/o the previous
get_device() in that case.
This lead to stale xarray entries after device add / remove cycles. In the
case when a previously used struct gendisk pointer (xarray index) would be
used again, because blk_alloc_disk() happened to return such a pointer, the
xa_insert() in dax_add_host() would fail and go to out_dax, doing the extra
put_device() in the error path. In combination with an already flawed error
handling in dcssblk (device_register() cleanup), which needs to be
addressed in a separate patch, this resulted in a missing device_del() /
klist_del(), and eventually in the kernel crash with list_add corruption on
a subsequent device_add() / klist_add().
Fix this by adding the missing dax_remove_host() calls, and also move the
put_device() in the error path to restore the previous logic.
In the Linux kernel, the following vulnerability has been resolved:
drm/fbdev-generic: prohibit potential out-of-bounds access
The fbdev test of IGT may write after EOF, which lead to out-of-bound
access for drm drivers with fbdev-generic. For example, run fbdev test
on a x86+ast2400 platform, with 1680x1050 resolution, will cause the
linux kernel hang with the following call trace:
Oops: 0000 [#1] PREEMPT SMP PTI
[IGT] fbdev: starting subtest eof
Workqueue: events drm_fb_helper_damage_work [drm_kms_helper]
[IGT] fbdev: starting subtest nullptr
RIP: 0010:memcpy_erms+0xa/0x20
RSP: 0018:ffffa17d40167d98 EFLAGS: 00010246
RAX: ffffa17d4eb7fa80 RBX: ffffa17d40e0aa80 RCX: 00000000000014c0
RDX: 0000000000001a40 RSI: ffffa17d40e0b000 RDI: ffffa17d4eb80000
RBP: ffffa17d40167e20 R08: 0000000000000000 R09: ffff89522ecff8c0
R10: ffffa17d4e4c5000 R11: 0000000000000000 R12: ffffa17d4eb7fa80
R13: 0000000000001a40 R14: 000000000000041a R15: ffffa17d40167e30
FS: 0000000000000000(0000) GS:ffff895257380000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffa17d40e0b000 CR3: 00000001eaeca006 CR4: 00000000001706e0
Call Trace:
<TASK>
? drm_fbdev_generic_helper_fb_dirty+0x207/0x330 [drm_kms_helper]
drm_fb_helper_damage_work+0x8f/0x170 [drm_kms_helper]
process_one_work+0x21f/0x430
worker_thread+0x4e/0x3c0
? __pfx_worker_thread+0x10/0x10
kthread+0xf4/0x120
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2c/0x50
</TASK>
CR2: ffffa17d40e0b000
---[ end trace 0000000000000000 ]---
The is because damage rectangles computed by
drm_fb_helper_memory_range_to_clip() function is not guaranteed to be
bound in the screen's active display area. Possible reasons are:
1) Buffers are allocated in the granularity of page size, for mmap system
call support. The shadow screen buffer consumed by fbdev emulation may
also choosed be page size aligned.
2) The DIV_ROUND_UP() used in drm_fb_helper_memory_range_to_clip()
will introduce off-by-one error.
For example, on a 16KB page size system, in order to store a 1920x1080
XRGB framebuffer, we need allocate 507 pages. Unfortunately, the size
1920*1080*4 can not be divided exactly by 16KB.
1920 * 1080 * 4 = 8294400 bytes
506 * 16 * 1024 = 8290304 bytes
507 * 16 * 1024 = 8306688 bytes
line_length = 1920*4 = 7680 bytes
507 * 16 * 1024 / 7680 = 1081.6
off / line_length = 507 * 16 * 1024 / 7680 = 1081
DIV_ROUND_UP(507 * 16 * 1024, 7680) will yeild 1082
memcpy_toio() typically issue the copy line by line, when copy the last
line, out-of-bound access will be happen. Because:
1082 * line_length = 1082 * 7680 = 8309760, and 8309760 > 8306688
Note that userspace may still write to the invisiable area if a larger
buffer than width x stride is exposed. But it is not a big issue as
long as there still have memory resolve the access if not drafting so
far.
- Also limit the y1 (Daniel)
- keep fix patch it to minimal (Daniel)
- screen_size is page size aligned because of it need mmap (Thomas)
- Adding fixes tag (Thomas)
In the Linux kernel, the following vulnerability has been resolved:
net: nsh: Use correct mac_offset to unwind gso skb in nsh_gso_segment()
As the call trace shows, skb_panic was caused by wrong skb->mac_header
in nsh_gso_segment():
invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 3 PID: 2737 Comm: syz Not tainted 6.3.0-next-20230505 #1
RIP: 0010:skb_panic+0xda/0xe0
call Trace:
skb_push+0x91/0xa0
nsh_gso_segment+0x4f3/0x570
skb_mac_gso_segment+0x19e/0x270
__skb_gso_segment+0x1e8/0x3c0
validate_xmit_skb+0x452/0x890
validate_xmit_skb_list+0x99/0xd0
sch_direct_xmit+0x294/0x7c0
__dev_queue_xmit+0x16f0/0x1d70
packet_xmit+0x185/0x210
packet_snd+0xc15/0x1170
packet_sendmsg+0x7b/0xa0
sock_sendmsg+0x14f/0x160
The root cause is:
nsh_gso_segment() use skb->network_header - nhoff to reset mac_header
in skb_gso_error_unwind() if inner-layer protocol gso fails.
However, skb->network_header may be reset by inner-layer protocol
gso function e.g. mpls_gso_segment. skb->mac_header reset by the
inaccurate network_header will be larger than skb headroom.
nsh_gso_segment
nhoff = skb->network_header - skb->mac_header;
__skb_pull(skb,nsh_len)
skb_mac_gso_segment
mpls_gso_segment
skb_reset_network_header(skb);//skb->network_header+=nsh_len
return -EINVAL;
skb_gso_error_unwind
skb_push(skb, nsh_len);
skb->mac_header = skb->network_header - nhoff;
// skb->mac_header > skb->headroom, cause skb_push panic
Use correct mac_offset to restore mac_header and get rid of nhoff.
In the Linux kernel, the following vulnerability has been resolved:
rcu: dump vmalloc memory info safely
Currently, for double invoke call_rcu(), will dump rcu_head objects memory
info, if the objects is not allocated from the slab allocator, the
vmalloc_dump_obj() will be invoke and the vmap_area_lock spinlock need to
be held, since the call_rcu() can be invoked in interrupt context,
therefore, there is a possibility of spinlock deadlock scenarios.
And in Preempt-RT kernel, the rcutorture test also trigger the following
lockdep warning:
BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0
preempt_count: 1, expected: 0
RCU nest depth: 1, expected: 1
3 locks held by swapper/0/1:
#0: ffffffffb534ee80 (fullstop_mutex){+.+.}-{4:4}, at: torture_init_begin+0x24/0xa0
#1: ffffffffb5307940 (rcu_read_lock){....}-{1:3}, at: rcu_torture_init+0x1ec7/0x2370
#2: ffffffffb536af40 (vmap_area_lock){+.+.}-{3:3}, at: find_vmap_area+0x1f/0x70
irq event stamp: 565512
hardirqs last enabled at (565511): [<ffffffffb379b138>] __call_rcu_common+0x218/0x940
hardirqs last disabled at (565512): [<ffffffffb5804262>] rcu_torture_init+0x20b2/0x2370
softirqs last enabled at (399112): [<ffffffffb36b2586>] __local_bh_enable_ip+0x126/0x170
softirqs last disabled at (399106): [<ffffffffb43fef59>] inet_register_protosw+0x9/0x1d0
Preemption disabled at:
[<ffffffffb58040c3>] rcu_torture_init+0x1f13/0x2370
CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 6.5.0-rc4-rt2-yocto-preempt-rt+ #15
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x68/0xb0
dump_stack+0x14/0x20
__might_resched+0x1aa/0x280
? __pfx_rcu_torture_err_cb+0x10/0x10
rt_spin_lock+0x53/0x130
? find_vmap_area+0x1f/0x70
find_vmap_area+0x1f/0x70
vmalloc_dump_obj+0x20/0x60
mem_dump_obj+0x22/0x90
__call_rcu_common+0x5bf/0x940
? debug_smp_processor_id+0x1b/0x30
call_rcu_hurry+0x14/0x20
rcu_torture_init+0x1f82/0x2370
? __pfx_rcu_torture_leak_cb+0x10/0x10
? __pfx_rcu_torture_leak_cb+0x10/0x10
? __pfx_rcu_torture_init+0x10/0x10
do_one_initcall+0x6c/0x300
? debug_smp_processor_id+0x1b/0x30
kernel_init_freeable+0x2b9/0x540
? __pfx_kernel_init+0x10/0x10
kernel_init+0x1f/0x150
ret_from_fork+0x40/0x50
? __pfx_kernel_init+0x10/0x10
ret_from_fork_asm+0x1b/0x30
</TASK>
The previous patch fixes this by using the deadlock-safe best-effort
version of find_vm_area. However, in case of failure print the fact that
the pointer was a vmalloc pointer so that we print at least something.
In the Linux kernel, the following vulnerability has been resolved:
kcm: Fix memory leak in error path of kcm_sendmsg()
syzbot reported a memory leak like below:
BUG: memory leak
unreferenced object 0xffff88810b088c00 (size 240):
comm "syz-executor186", pid 5012, jiffies 4294943306 (age 13.680s)
hex dump (first 32 bytes):
00 89 08 0b 81 88 ff ff 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff83e5d5ff>] __alloc_skb+0x1ef/0x230 net/core/skbuff.c:634
[<ffffffff84606e59>] alloc_skb include/linux/skbuff.h:1289 [inline]
[<ffffffff84606e59>] kcm_sendmsg+0x269/0x1050 net/kcm/kcmsock.c:815
[<ffffffff83e479c6>] sock_sendmsg_nosec net/socket.c:725 [inline]
[<ffffffff83e479c6>] sock_sendmsg+0x56/0xb0 net/socket.c:748
[<ffffffff83e47f55>] ____sys_sendmsg+0x365/0x470 net/socket.c:2494
[<ffffffff83e4c389>] ___sys_sendmsg+0xc9/0x130 net/socket.c:2548
[<ffffffff83e4c536>] __sys_sendmsg+0xa6/0x120 net/socket.c:2577
[<ffffffff84ad7bb8>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff84ad7bb8>] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
[<ffffffff84c0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
In kcm_sendmsg(), kcm_tx_msg(head)->last_skb is used as a cursor to append
newly allocated skbs to 'head'. If some bytes are copied, an error occurred,
and jumped to out_error label, 'last_skb' is left unmodified. A later
kcm_sendmsg() will use an obsoleted 'last_skb' reference, corrupting the
'head' frag_list and causing the leak.
This patch fixes this issue by properly updating the last allocated skb in
'last_skb'.
In the Linux kernel, the following vulnerability has been resolved:
pinctrl: rockchip: Fix refcount leak in rockchip_pinctrl_parse_groups
of_find_node_by_phandle() 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:
usb: rndis_host: Secure rndis_query check against int overflow
Variables off and len typed as uint32 in rndis_query function
are controlled by incoming RNDIS response message thus their
value may be manipulated. Setting off to a unexpectetly large
value will cause the sum with len and 8 to overflow and pass
the implemented validation step. Consequently the response
pointer will be referring to a location past the expected
buffer boundaries allowing information leakage e.g. via
RNDIS_OID_802_3_PERMANENT_ADDRESS OID.
In the Linux kernel, the following vulnerability has been resolved:
media: rcar_fdp1: Fix refcount leak in probe and remove function
rcar_fcp_get() take reference, which should be balanced with
rcar_fcp_put(). Add missing rcar_fcp_put() in fdp1_remove and
the error paths of fdp1_probe() to fix this.
[hverkuil: resolve merge conflict, remove() is now void]
In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix DMA-API call trace on NVMe LS requests
The following message and call trace was seen with debug kernels:
DMA-API: qla2xxx 0000:41:00.0: device driver failed to check map
error [device address=0x00000002a3ff38d8] [size=1024 bytes] [mapped as
single]
WARNING: CPU: 0 PID: 2930 at kernel/dma/debug.c:1017
check_unmap+0xf42/0x1990
Call Trace:
debug_dma_unmap_page+0xc9/0x100
qla_nvme_ls_unmap+0x141/0x210 [qla2xxx]
Remove DMA mapping from the driver altogether, as it is already done by FC
layer. This prevents the warning.
In the Linux kernel, the following vulnerability has been resolved:
blk-cgroup: dropping parent refcount after pd_free_fn() is done
Some cgroup policies will access parent pd through child pd even
after pd_offline_fn() is done. If pd_free_fn() for parent is called
before child, then UAF can be triggered. Hence it's better to guarantee
the order of pd_free_fn().
Currently refcount of parent blkg is dropped in __blkg_release(), which
is before pd_free_fn() is called in blkg_free_work_fn() while
blkg_free_work_fn() is called asynchronously.
This patch make sure pd_free_fn() called from removing cgroup is ordered
by delaying dropping parent refcount after calling pd_free_fn() for
child.
BTW, pd_free_fn() will also be called from blkcg_deactivate_policy()
from deleting device, and following patches will guarantee the order.
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: fix potential memory leak in mlx5e_init_rep_rx
The memory pointed to by the priv->rx_res pointer is not freed in the error
path of mlx5e_init_rep_rx, which can lead to a memory leak. Fix by freeing
the memory in the error path, thereby making the error path identical to
mlx5e_cleanup_rep_rx().
In the Linux kernel, the following vulnerability has been resolved:
can: isotp: check CAN address family in isotp_bind()
Add missing check to block non-AF_CAN binds.
Syzbot created some code which matched the right sockaddr struct size
but used AF_XDP (0x2C) instead of AF_CAN (0x1D) in the address family
field:
bind$xdp(r2, &(0x7f0000000540)={0x2c, 0x0, r4, 0x0, r2}, 0x10)
^^^^
This has no funtional impact but the userspace should be notified about
the wrong address family field content.
In the Linux kernel, the following vulnerability has been resolved:
mtd: rawnand: fsl_upm: Fix an off-by one test in fun_exec_op()
'op-cs' is copied in 'fun->mchip_number' which is used to access the
'mchip_offsets' and the 'rnb_gpio' arrays.
These arrays have NAND_MAX_CHIPS elements, so the index must be below this
limit.
Fix the sanity check in order to avoid the NAND_MAX_CHIPS value. This
would lead to out-of-bound accesses.
In the Linux kernel, the following vulnerability has been resolved:
media: mtk-jpeg: Fix use after free bug due to uncanceled work
In mtk_jpeg_probe, &jpeg->job_timeout_work is bound with
mtk_jpeg_job_timeout_work. Then mtk_jpeg_dec_device_run
and mtk_jpeg_enc_device_run may be called to start the
work.
If we remove the module which will call mtk_jpeg_remove
to make cleanup, there may be a unfinished work. The
possible sequence is as follows, which will cause a
typical UAF bug.
Fix it by canceling the work before cleanup in the mtk_jpeg_remove
CPU0 CPU1
|mtk_jpeg_job_timeout_work
mtk_jpeg_remove |
v4l2_m2m_release |
kfree(m2m_dev); |
|
| v4l2_m2m_get_curr_priv
| m2m_dev->curr_ctx //use
In the Linux kernel, the following vulnerability has been resolved:
scsi: lpfc: Prevent lpfc_debugfs_lockstat_write() buffer overflow
A static code analysis tool flagged the possibility of buffer overflow when
using copy_from_user() for a debugfs entry.
Currently, it is possible that copy_from_user() copies more bytes than what
would fit in the mybuf char array. Add a min() restriction check between
sizeof(mybuf) - 1 and nbytes passed from the userspace buffer to protect
against buffer overflow.
In the Linux kernel, the following vulnerability has been resolved:
driver: soc: xilinx: use _safe loop iterator to avoid a use after free
The hash_for_each_possible() loop dereferences "eve_data" to get the
next item on the list. However the loop frees eve_data so it leads to
a use after free. Use hash_for_each_possible_safe() instead.
In the Linux kernel, the following vulnerability has been resolved:
scsi: qedi: Fix use after free bug in qedi_remove()
In qedi_probe() we call __qedi_probe() which initializes
&qedi->recovery_work with qedi_recovery_handler() and
&qedi->board_disable_work with qedi_board_disable_work().
When qedi_schedule_recovery_handler() is called, schedule_delayed_work()
will finally start the work.
In qedi_remove(), which is called to remove the driver, the following
sequence may be observed:
Fix this by finishing the work before cleanup in qedi_remove().
CPU0 CPU1
|qedi_recovery_handler
qedi_remove |
__qedi_remove |
iscsi_host_free |
scsi_host_put |
//free shost |
|iscsi_host_for_each_session
|//use qedi->shost
Cancel recovery_work and board_disable_work in __qedi_remove().
In the Linux kernel, the following vulnerability has been resolved:
fs: Protect reconfiguration of sb read-write from racing writes
The reconfigure / remount code takes a lot of effort to protect
filesystem's reconfiguration code from racing writes on remounting
read-only. However during remounting read-only filesystem to read-write
mode userspace writes can start immediately once we clear SB_RDONLY
flag. This is inconvenient for example for ext4 because we need to do
some writes to the filesystem (such as preparation of quota files)
before we can take userspace writes so we are clearing SB_RDONLY flag
before we are fully ready to accept userpace writes and syzbot has found
a way to exploit this [1]. Also as far as I'm reading the code
the filesystem remount code was protected from racing writes in the
legacy mount path by the mount's MNT_READONLY flag so this is relatively
new problem. It is actually fairly easy to protect remount read-write
from racing writes using sb->s_readonly_remount flag so let's just do
that instead of having to workaround these races in the filesystem code.
[1] https://lore.kernel.org/all/00000000000006a0df05f6667499@google.com/T/
In the Linux kernel, the following vulnerability has been resolved:
regulator: stm32-pwr: fix of_iomap leak
Smatch reports:
drivers/regulator/stm32-pwr.c:166 stm32_pwr_regulator_probe() warn:
'base' from of_iomap() not released on lines: 151,166.
In stm32_pwr_regulator_probe(), base is not released
when devm_kzalloc() fails to allocate memory or
devm_regulator_register() fails to register a new regulator device,
which may cause a leak.
To fix this issue, replace of_iomap() with
devm_platform_ioremap_resource(). devm_platform_ioremap_resource()
is a specialized function for platform devices.
It allows 'base' to be automatically released whether the probe
function succeeds or fails.
Besides, use IS_ERR(base) instead of !base
as the return value of devm_platform_ioremap_resource()
can either be a pointer to the remapped memory or
an ERR_PTR() encoded error code if the operation fails.