In the Linux kernel, the following vulnerability has been resolved:
slip: make slhc_remember() more robust against malicious packets
syzbot found that slhc_remember() was missing checks against
malicious packets [1].
slhc_remember() only checked the size of the packet was at least 20,
which is not good enough.
We need to make sure the packet includes the IPv4 and TCP header
that are supposed to be carried.
Add iph and th pointers to make the code more readable.
[1]
BUG: KMSAN: uninit-value in slhc_remember+0x2e8/0x7b0 drivers/net/slip/slhc.c:666
slhc_remember+0x2e8/0x7b0 drivers/net/slip/slhc.c:666
ppp_receive_nonmp_frame+0xe45/0x35e0 drivers/net/ppp/ppp_generic.c:2455
ppp_receive_frame drivers/net/ppp/ppp_generic.c:2372 [inline]
ppp_do_recv+0x65f/0x40d0 drivers/net/ppp/ppp_generic.c:2212
ppp_input+0x7dc/0xe60 drivers/net/ppp/ppp_generic.c:2327
pppoe_rcv_core+0x1d3/0x720 drivers/net/ppp/pppoe.c:379
sk_backlog_rcv+0x13b/0x420 include/net/sock.h:1113
__release_sock+0x1da/0x330 net/core/sock.c:3072
release_sock+0x6b/0x250 net/core/sock.c:3626
pppoe_sendmsg+0x2b8/0xb90 drivers/net/ppp/pppoe.c:903
sock_sendmsg_nosec net/socket.c:729 [inline]
__sock_sendmsg+0x30f/0x380 net/socket.c:744
____sys_sendmsg+0x903/0xb60 net/socket.c:2602
___sys_sendmsg+0x28d/0x3c0 net/socket.c:2656
__sys_sendmmsg+0x3c1/0x960 net/socket.c:2742
__do_sys_sendmmsg net/socket.c:2771 [inline]
__se_sys_sendmmsg net/socket.c:2768 [inline]
__x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2768
x64_sys_call+0xb6e/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:308
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Uninit was created at:
slab_post_alloc_hook mm/slub.c:4091 [inline]
slab_alloc_node mm/slub.c:4134 [inline]
kmem_cache_alloc_node_noprof+0x6bf/0xb80 mm/slub.c:4186
kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:587
__alloc_skb+0x363/0x7b0 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1322 [inline]
sock_wmalloc+0xfe/0x1a0 net/core/sock.c:2732
pppoe_sendmsg+0x3a7/0xb90 drivers/net/ppp/pppoe.c:867
sock_sendmsg_nosec net/socket.c:729 [inline]
__sock_sendmsg+0x30f/0x380 net/socket.c:744
____sys_sendmsg+0x903/0xb60 net/socket.c:2602
___sys_sendmsg+0x28d/0x3c0 net/socket.c:2656
__sys_sendmmsg+0x3c1/0x960 net/socket.c:2742
__do_sys_sendmmsg net/socket.c:2771 [inline]
__se_sys_sendmmsg net/socket.c:2768 [inline]
__x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2768
x64_sys_call+0xb6e/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:308
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
CPU: 0 UID: 0 PID: 5460 Comm: syz.2.33 Not tainted 6.12.0-rc2-syzkaller-00006-g87d6aab2389e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
In the Linux kernel, the following vulnerability has been resolved:
ALSA: asihpi: Fix potential OOB array access
ASIHPI driver stores some values in the static array upon a response
from the driver, and its index depends on the firmware. We shouldn't
trust it blindly.
This patch adds a sanity check of the array index to fit in the array
size.
In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: lantiq_etop: fix memory disclosure
When applying padding, the buffer is not zeroed, which results in memory
disclosure. The mentioned data is observed on the wire. This patch uses
skb_put_padto() to pad Ethernet frames properly. The mentioned function
zeroes the expanded buffer.
In case the packet cannot be padded it is silently dropped. Statistics
are also not incremented. This driver does not support statistics in the
old 32-bit format or the new 64-bit format. These will be added in the
future. In its current form, the patch should be easily backported to
stable versions.
Ethernet MACs on Amazon-SE and Danube cannot do padding of the packets
in hardware, so software padding must be applied.
In the Linux kernel, the following vulnerability has been resolved:
cifs: Fix buffer overflow when parsing NFS reparse points
ReparseDataLength is sum of the InodeType size and DataBuffer size.
So to get DataBuffer size it is needed to subtract InodeType's size from
ReparseDataLength.
Function cifs_strndup_from_utf16() is currentlly accessing buf->DataBuffer
at position after the end of the buffer because it does not subtract
InodeType size from the length. Fix this problem and correctly subtract
variable len.
Member InodeType is present only when reparse buffer is large enough. Check
for ReparseDataLength before accessing InodeType to prevent another invalid
memory access.
Major and minor rdev values are present also only when reparse buffer is
large enough. Check for reparse buffer size before calling reparse_mkdev().
In the Linux kernel, the following vulnerability has been resolved:
drm/stm: Avoid use-after-free issues with crtc and plane
ltdc_load() calls functions drm_crtc_init_with_planes(),
drm_universal_plane_init() and drm_encoder_init(). These functions
should not be called with parameters allocated with devm_kzalloc()
to avoid use-after-free issues [1].
Use allocations managed by the DRM framework.
Found by Linux Verification Center (linuxtesting.org).
[1]
https://lore.kernel.org/lkml/u366i76e3qhh3ra5oxrtngjtm2u5lterkekcz6y2jkndhuxzli@diujon4h7qwb/
In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: amdkfd_free_gtt_mem clear the correct pointer
Pass pointer reference to amdgpu_bo_unref to clear the correct pointer,
otherwise amdgpu_bo_unref clear the local variable, the original pointer
not set to NULL, this could cause use-after-free bug.
In the Linux kernel, the following vulnerability has been resolved:
platform/x86: x86-android-tablets: Fix use after free on platform_device_register() errors
x86_android_tablet_remove() frees the pdevs[] array, so it should not
be used after calling x86_android_tablet_remove().
When platform_device_register() fails, store the pdevs[x] PTR_ERR() value
into the local ret variable before calling x86_android_tablet_remove()
to avoid using pdevs[] after it has been freed.
In the Linux kernel, the following vulnerability has been resolved:
ext4: drop ppath from ext4_ext_replay_update_ex() to avoid double-free
When calling ext4_force_split_extent_at() in ext4_ext_replay_update_ex(),
the 'ppath' is updated but it is the 'path' that is freed, thus potentially
triggering a double-free in the following process:
ext4_ext_replay_update_ex
ppath = path
ext4_force_split_extent_at(&ppath)
ext4_split_extent_at
ext4_ext_insert_extent
ext4_ext_create_new_leaf
ext4_ext_grow_indepth
ext4_find_extent
if (depth > path[0].p_maxdepth)
kfree(path) ---> path First freed
*orig_path = path = NULL ---> null ppath
kfree(path) ---> path double-free !!!
So drop the unnecessary ppath and use path directly to avoid this problem.
And use ext4_find_extent() directly to update path, avoiding unnecessary
memory allocation and freeing. Also, propagate the error returned by
ext4_find_extent() instead of using strange error codes.
In the Linux kernel, the following vulnerability has been resolved:
aoe: fix the potential use-after-free problem in more places
For fixing CVE-2023-6270, f98364e92662 ("aoe: fix the potential
use-after-free problem in aoecmd_cfg_pkts") makes tx() calling dev_put()
instead of doing in aoecmd_cfg_pkts(). It avoids that the tx() runs
into use-after-free.
Then Nicolai Stange found more places in aoe have potential use-after-free
problem with tx(). e.g. revalidate(), aoecmd_ata_rw(), resend(), probe()
and aoecmd_cfg_rsp(). Those functions also use aoenet_xmit() to push
packet to tx queue. So they should also use dev_hold() to increase the
refcnt of skb->dev.
On the other hand, moving dev_put() to tx() causes that the refcnt of
skb->dev be reduced to a negative value, because corresponding
dev_hold() are not called in revalidate(), aoecmd_ata_rw(), resend(),
probe(), and aoecmd_cfg_rsp(). This patch fixed this issue.
In the Linux kernel, the following vulnerability has been resolved:
media: venus: fix use after free bug in venus_remove due to race condition
in venus_probe, core->work is bound with venus_sys_error_handler, which is
used to handle error. The code use core->sys_err_done to make sync work.
The core->work is started in venus_event_notify.
If we call venus_remove, there might be an unfished work. The possible
sequence is as follows:
CPU0 CPU1
|venus_sys_error_handler
venus_remove |
hfi_destroy |
venus_hfi_destroy |
kfree(hdev); |
|hfi_reinit
|venus_hfi_queues_reinit
|//use hdev
Fix it by canceling the work in venus_remove.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix index out of bounds in DCN30 color transformation
This commit addresses a potential index out of bounds issue in the
`cm3_helper_translate_curve_to_hw_format` function in the DCN30 color
management module. The issue could occur when the index 'i' exceeds the
number of transfer function points (TRANSFER_FUNC_POINTS).
The fix adds a check to ensure 'i' is within bounds before accessing the
transfer function points. If 'i' is out of bounds, the function returns
false to indicate an error.
drivers/gpu/drm/amd/amdgpu/../display/dc/dcn30/dcn30_cm_common.c:180 cm3_helper_translate_curve_to_hw_format() error: buffer overflow 'output_tf->tf_pts.red' 1025 <= s32max
drivers/gpu/drm/amd/amdgpu/../display/dc/dcn30/dcn30_cm_common.c:181 cm3_helper_translate_curve_to_hw_format() error: buffer overflow 'output_tf->tf_pts.green' 1025 <= s32max
drivers/gpu/drm/amd/amdgpu/../display/dc/dcn30/dcn30_cm_common.c:182 cm3_helper_translate_curve_to_hw_format() error: buffer overflow 'output_tf->tf_pts.blue' 1025 <= s32max
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: cancel dqi_sync_work before freeing oinfo
ocfs2_global_read_info() will initialize and schedule dqi_sync_work at the
end, if error occurs after successfully reading global quota, it will
trigger the following warning with CONFIG_DEBUG_OBJECTS_* enabled:
ODEBUG: free active (active state 0) object: 00000000d8b0ce28 object type: timer_list hint: qsync_work_fn+0x0/0x16c
This reports that there is an active delayed work when freeing oinfo in
error handling, so cancel dqi_sync_work first. BTW, return status instead
of -1 when .read_file_info fails.
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix timer use-after-free on failed mount
Syzbot has found an ODEBUG bug in ext4_fill_super
The del_timer_sync function cancels the s_err_report timer,
which reminds about filesystem errors daily. We should
guarantee the timer is no longer active before kfree(sbi).
When filesystem mounting fails, the flow goes to failed_mount3,
where an error occurs when ext4_stop_mmpd is called, causing
a read I/O failure. This triggers the ext4_handle_error function
that ultimately re-arms the timer,
leaving the s_err_report timer active before kfree(sbi) is called.
Fix the issue by canceling the s_err_report timer after calling ext4_stop_mmpd.
In the Linux kernel, the following vulnerability has been resolved:
net/xen-netback: prevent UAF in xenvif_flush_hash()
During the list_for_each_entry_rcu iteration call of xenvif_flush_hash,
kfree_rcu does not exist inside the rcu read critical section, so if
kfree_rcu is called when the rcu grace period ends during the iteration,
UAF occurs when accessing head->next after the entry becomes free.
Therefore, to solve this, you need to change it to list_for_each_entry_safe.
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: fix array out-of-bound access in SoC stats
Currently, the ath11k_soc_dp_stats::hal_reo_error array is defined with a
maximum size of DP_REO_DST_RING_MAX. However, the ath11k_dp_process_rx()
function access ath11k_soc_dp_stats::hal_reo_error using the REO
destination SRNG ring ID, which is incorrect. SRNG ring ID differ from
normal ring ID, and this usage leads to out-of-bounds array access. To fix
this issue, modify ath11k_dp_process_rx() to use the normal ring ID
directly instead of the SRNG ring ID to avoid out-of-bounds array access.
Tested-on: QCN9074 hw1.0 PCI WLAN.HK.2.7.0.1-01744-QCAHKSWPL_SILICONZ-1
In the Linux kernel, the following vulnerability has been resolved:
fbdev: pxafb: Fix possible use after free in pxafb_task()
In the pxafb_probe function, it calls the pxafb_init_fbinfo function,
after which &fbi->task is associated with pxafb_task. Moreover,
within this pxafb_init_fbinfo function, the pxafb_blank function
within the &pxafb_ops struct is capable of scheduling work.
If we remove the module which will call pxafb_remove to make cleanup,
it will call unregister_framebuffer function which can call
do_unregister_framebuffer to free fbi->fb through
put_fb_info(fb_info), while the work mentioned above will be used.
The sequence of operations that may lead to a UAF bug is as follows:
CPU0 CPU1
| pxafb_task
pxafb_remove |
unregister_framebuffer(info) |
do_unregister_framebuffer(fb_info) |
put_fb_info(fb_info) |
// free fbi->fb | set_ctrlr_state(fbi, state)
| __pxafb_lcd_power(fbi, 0)
| fbi->lcd_power(on, &fbi->fb.var)
| //use fbi->fb
Fix it by ensuring that the work is canceled before proceeding
with the cleanup in pxafb_remove.
Note that only root user can remove the driver at runtime.
In the Linux kernel, the following vulnerability has been resolved:
jfs: Fix uninit-value access of new_ea in ea_buffer
syzbot reports that lzo1x_1_do_compress is using uninit-value:
=====================================================
BUG: KMSAN: uninit-value in lzo1x_1_do_compress+0x19f9/0x2510 lib/lzo/lzo1x_compress.c:178
...
Uninit was stored to memory at:
ea_put fs/jfs/xattr.c:639 [inline]
...
Local variable ea_buf created at:
__jfs_setxattr+0x5d/0x1ae0 fs/jfs/xattr.c:662
__jfs_xattr_set+0xe6/0x1f0 fs/jfs/xattr.c:934
=====================================================
The reason is ea_buf->new_ea is not initialized properly.
Fix this by using memset to empty its content at the beginning
in ea_get().
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix index out of bounds in DCN30 degamma hardware format translation
This commit addresses a potential index out of bounds issue in the
`cm3_helper_translate_curve_to_degamma_hw_format` function in the DCN30
color management module. The issue could occur when the index 'i'
exceeds the number of transfer function points (TRANSFER_FUNC_POINTS).
The fix adds a check to ensure 'i' is within bounds before accessing the
transfer function points. If 'i' is out of bounds, the function returns
false to indicate an error.
Reported by smatch:
drivers/gpu/drm/amd/amdgpu/../display/dc/dcn30/dcn30_cm_common.c:338 cm3_helper_translate_curve_to_degamma_hw_format() error: buffer overflow 'output_tf->tf_pts.red' 1025 <= s32max
drivers/gpu/drm/amd/amdgpu/../display/dc/dcn30/dcn30_cm_common.c:339 cm3_helper_translate_curve_to_degamma_hw_format() error: buffer overflow 'output_tf->tf_pts.green' 1025 <= s32max
drivers/gpu/drm/amd/amdgpu/../display/dc/dcn30/dcn30_cm_common.c:340 cm3_helper_translate_curve_to_degamma_hw_format() error: buffer overflow 'output_tf->tf_pts.blue' 1025 <= s32max
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix index out of bounds in degamma hardware format translation
Fixes index out of bounds issue in
`cm_helper_translate_curve_to_degamma_hw_format` function. The issue
could occur when the index 'i' exceeds the number of transfer function
points (TRANSFER_FUNC_POINTS).
The fix adds a check to ensure 'i' is within bounds before accessing the
transfer function points. If 'i' is out of bounds the function returns
false to indicate an error.
Reported by smatch:
drivers/gpu/drm/amd/amdgpu/../display/dc/dcn10/dcn10_cm_common.c:594 cm_helper_translate_curve_to_degamma_hw_format() error: buffer overflow 'output_tf->tf_pts.red' 1025 <= s32max
drivers/gpu/drm/amd/amdgpu/../display/dc/dcn10/dcn10_cm_common.c:595 cm_helper_translate_curve_to_degamma_hw_format() error: buffer overflow 'output_tf->tf_pts.green' 1025 <= s32max
drivers/gpu/drm/amd/amdgpu/../display/dc/dcn10/dcn10_cm_common.c:596 cm_helper_translate_curve_to_degamma_hw_format() error: buffer overflow 'output_tf->tf_pts.blue' 1025 <= s32max
In the Linux kernel, the following vulnerability has been resolved:
ext4: avoid use-after-free in ext4_ext_show_leaf()
In ext4_find_extent(), path may be freed by error or be reallocated, so
using a previously saved *ppath may have been freed and thus may trigger
use-after-free, as follows:
ext4_split_extent
path = *ppath;
ext4_split_extent_at(ppath)
path = ext4_find_extent(ppath)
ext4_split_extent_at(ppath)
// ext4_find_extent fails to free path
// but zeroout succeeds
ext4_ext_show_leaf(inode, path)
eh = path[depth].p_hdr
// path use-after-free !!!
Similar to ext4_split_extent_at(), we use *ppath directly as an input to
ext4_ext_show_leaf(). Fix a spelling error by the way.
Same problem in ext4_ext_handle_unwritten_extents(). Since 'path' is only
used in ext4_ext_show_leaf(), remove 'path' and use *ppath directly.
This issue is triggered only when EXT_DEBUG is defined and therefore does
not affect functionality.
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix slab-use-after-free in ext4_split_extent_at()
We hit the following use-after-free:
==================================================================
BUG: KASAN: slab-use-after-free in ext4_split_extent_at+0xba8/0xcc0
Read of size 2 at addr ffff88810548ed08 by task kworker/u20:0/40
CPU: 0 PID: 40 Comm: kworker/u20:0 Not tainted 6.9.0-dirty #724
Call Trace:
<TASK>
kasan_report+0x93/0xc0
ext4_split_extent_at+0xba8/0xcc0
ext4_split_extent.isra.0+0x18f/0x500
ext4_split_convert_extents+0x275/0x750
ext4_ext_handle_unwritten_extents+0x73e/0x1580
ext4_ext_map_blocks+0xe20/0x2dc0
ext4_map_blocks+0x724/0x1700
ext4_do_writepages+0x12d6/0x2a70
[...]
Allocated by task 40:
__kmalloc_noprof+0x1ac/0x480
ext4_find_extent+0xf3b/0x1e70
ext4_ext_map_blocks+0x188/0x2dc0
ext4_map_blocks+0x724/0x1700
ext4_do_writepages+0x12d6/0x2a70
[...]
Freed by task 40:
kfree+0xf1/0x2b0
ext4_find_extent+0xa71/0x1e70
ext4_ext_insert_extent+0xa22/0x3260
ext4_split_extent_at+0x3ef/0xcc0
ext4_split_extent.isra.0+0x18f/0x500
ext4_split_convert_extents+0x275/0x750
ext4_ext_handle_unwritten_extents+0x73e/0x1580
ext4_ext_map_blocks+0xe20/0x2dc0
ext4_map_blocks+0x724/0x1700
ext4_do_writepages+0x12d6/0x2a70
[...]
==================================================================
The flow of issue triggering is as follows:
ext4_split_extent_at
path = *ppath
ext4_ext_insert_extent(ppath)
ext4_ext_create_new_leaf(ppath)
ext4_find_extent(orig_path)
path = *orig_path
read_extent_tree_block
// return -ENOMEM or -EIO
ext4_free_ext_path(path)
kfree(path)
*orig_path = NULL
a. If err is -ENOMEM:
ext4_ext_dirty(path + path->p_depth)
// path use-after-free !!!
b. If err is -EIO and we have EXT_DEBUG defined:
ext4_ext_show_leaf(path)
eh = path[depth].p_hdr
// path also use-after-free !!!
So when trying to zeroout or fix the extent length, call ext4_find_extent()
to update the path.
In addition we use *ppath directly as an ext4_ext_show_leaf() input to
avoid possible use-after-free when EXT_DEBUG is defined, and to avoid
unnecessary path updates.
In the Linux kernel, the following vulnerability has been resolved:
ext4: aovid use-after-free in ext4_ext_insert_extent()
As Ojaswin mentioned in Link, in ext4_ext_insert_extent(), if the path is
reallocated in ext4_ext_create_new_leaf(), we'll use the stale path and
cause UAF. Below is a sample trace with dummy values:
ext4_ext_insert_extent
path = *ppath = 2000
ext4_ext_create_new_leaf(ppath)
ext4_find_extent(ppath)
path = *ppath = 2000
if (depth > path[0].p_maxdepth)
kfree(path = 2000);
*ppath = path = NULL;
path = kcalloc() = 3000
*ppath = 3000;
return path;
/* here path is still 2000, UAF! */
eh = path[depth].p_hdr
==================================================================
BUG: KASAN: slab-use-after-free in ext4_ext_insert_extent+0x26d4/0x3330
Read of size 8 at addr ffff8881027bf7d0 by task kworker/u36:1/179
CPU: 3 UID: 0 PID: 179 Comm: kworker/u6:1 Not tainted 6.11.0-rc2-dirty #866
Call Trace:
<TASK>
ext4_ext_insert_extent+0x26d4/0x3330
ext4_ext_map_blocks+0xe22/0x2d40
ext4_map_blocks+0x71e/0x1700
ext4_do_writepages+0x1290/0x2800
[...]
Allocated by task 179:
ext4_find_extent+0x81c/0x1f70
ext4_ext_map_blocks+0x146/0x2d40
ext4_map_blocks+0x71e/0x1700
ext4_do_writepages+0x1290/0x2800
ext4_writepages+0x26d/0x4e0
do_writepages+0x175/0x700
[...]
Freed by task 179:
kfree+0xcb/0x240
ext4_find_extent+0x7c0/0x1f70
ext4_ext_insert_extent+0xa26/0x3330
ext4_ext_map_blocks+0xe22/0x2d40
ext4_map_blocks+0x71e/0x1700
ext4_do_writepages+0x1290/0x2800
ext4_writepages+0x26d/0x4e0
do_writepages+0x175/0x700
[...]
==================================================================
So use *ppath to update the path to avoid the above problem.
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix double brelse() the buffer of the extents path
In ext4_ext_try_to_merge_up(), set path[1].p_bh to NULL after it has been
released, otherwise it may be released twice. An example of what triggers
this is as follows:
split2 map split1
|--------|-------|--------|
ext4_ext_map_blocks
ext4_ext_handle_unwritten_extents
ext4_split_convert_extents
// path->p_depth == 0
ext4_split_extent
// 1. do split1
ext4_split_extent_at
|ext4_ext_insert_extent
| ext4_ext_create_new_leaf
| ext4_ext_grow_indepth
| le16_add_cpu(&neh->eh_depth, 1)
| ext4_find_extent
| // return -ENOMEM
|// get error and try zeroout
|path = ext4_find_extent
| path->p_depth = 1
|ext4_ext_try_to_merge
| ext4_ext_try_to_merge_up
| path->p_depth = 0
| brelse(path[1].p_bh) ---> not set to NULL here
|// zeroout success
// 2. update path
ext4_find_extent
// 3. do split2
ext4_split_extent_at
ext4_ext_insert_extent
ext4_ext_create_new_leaf
ext4_ext_grow_indepth
le16_add_cpu(&neh->eh_depth, 1)
ext4_find_extent
path[0].p_bh = NULL;
path->p_depth = 1
read_extent_tree_block ---> return err
// path[1].p_bh is still the old value
ext4_free_ext_path
ext4_ext_drop_refs
// path->p_depth == 1
brelse(path[1].p_bh) ---> brelse a buffer twice
Finally got the following WARRNING when removing the buffer from lru:
============================================
VFS: brelse: Trying to free free buffer
WARNING: CPU: 2 PID: 72 at fs/buffer.c:1241 __brelse+0x58/0x90
CPU: 2 PID: 72 Comm: kworker/u19:1 Not tainted 6.9.0-dirty #716
RIP: 0010:__brelse+0x58/0x90
Call Trace:
<TASK>
__find_get_block+0x6e7/0x810
bdev_getblk+0x2b/0x480
__ext4_get_inode_loc+0x48a/0x1240
ext4_get_inode_loc+0xb2/0x150
ext4_reserve_inode_write+0xb7/0x230
__ext4_mark_inode_dirty+0x144/0x6a0
ext4_ext_insert_extent+0x9c8/0x3230
ext4_ext_map_blocks+0xf45/0x2dc0
ext4_map_blocks+0x724/0x1700
ext4_do_writepages+0x12d6/0x2a70
[...]
============================================
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix helper writes to read-only maps
Lonial found an issue that despite user- and BPF-side frozen BPF map
(like in case of .rodata), it was still possible to write into it from
a BPF program side through specific helpers having ARG_PTR_TO_{LONG,INT}
as arguments.
In check_func_arg() when the argument is as mentioned, the meta->raw_mode
is never set. Later, check_helper_mem_access(), under the case of
PTR_TO_MAP_VALUE as register base type, it assumes BPF_READ for the
subsequent call to check_map_access_type() and given the BPF map is
read-only it succeeds.
The helpers really need to be annotated as ARG_PTR_TO_{LONG,INT} | MEM_UNINIT
when results are written into them as opposed to read out of them. The
latter indicates that it's okay to pass a pointer to uninitialized memory
as the memory is written to anyway.
However, ARG_PTR_TO_{LONG,INT} is a special case of ARG_PTR_TO_FIXED_SIZE_MEM
just with additional alignment requirement. So it is better to just get
rid of the ARG_PTR_TO_{LONG,INT} special cases altogether and reuse the
fixed size memory types. For this, add MEM_ALIGNED to additionally ensure
alignment given these helpers write directly into the args via *<ptr> = val.
The .arg*_size has been initialized reflecting the actual sizeof(*<ptr>).
MEM_ALIGNED can only be used in combination with MEM_FIXED_SIZE annotated
argument types, since in !MEM_FIXED_SIZE cases the verifier does not know
the buffer size a priori and therefore cannot blindly write *<ptr> = val.
In the Linux kernel, the following vulnerability has been resolved:
ACPI: sysfs: validate return type of _STR method
Only buffer objects are valid return values of _STR.
If something else is returned description_show() will access invalid
memory.
In the Linux kernel, the following vulnerability has been resolved:
nbd: fix race between timeout and normal completion
If request timetout is handled by nbd_requeue_cmd(), normal completion
has to be stopped for avoiding to complete this requeued request, other
use-after-free can be triggered.
Fix the race by clearing NBD_CMD_INFLIGHT in nbd_requeue_cmd(), meantime
make sure that cmd->lock is grabbed for clearing the flag and the
requeue.
In the Linux kernel, the following vulnerability has been resolved:
block, bfq: fix uaf for accessing waker_bfqq after splitting
After commit 42c306ed7233 ("block, bfq: don't break merge chain in
bfq_split_bfqq()"), if the current procress is the last holder of bfqq,
the bfqq can be freed after bfq_split_bfqq(). Hence recored the bfqq and
then access bfqq->waker_bfqq may trigger UAF. What's more, the waker_bfqq
may in the merge chain of bfqq, hence just recored waker_bfqq is still
not safe.
Fix the problem by adding a helper bfq_waker_bfqq() to check if
bfqq->waker_bfqq is in the merge chain, and current procress is the only
holder.
In the Linux kernel, the following vulnerability has been resolved:
firmware: arm_scmi: Fix double free in OPTEE transport
Channels can be shared between protocols, avoid freeing the same channel
descriptors twice when unloading the stack.
In the Linux kernel, the following vulnerability has been resolved:
scsi: elx: libefc: Fix potential use after free in efc_nport_vport_del()
The kref_put() function will call nport->release if the refcount drops to
zero. The nport->release release function is _efc_nport_free() which frees
"nport". But then we dereference "nport" on the next line which is a use
after free. Re-order these lines to avoid the use after free.
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix potential oob read in nilfs_btree_check_delete()
The function nilfs_btree_check_delete(), which checks whether degeneration
to direct mapping occurs before deleting a b-tree entry, causes memory
access outside the block buffer when retrieving the maximum key if the
root node has no entries.
This does not usually happen because b-tree mappings with 0 child nodes
are never created by mkfs.nilfs2 or nilfs2 itself. However, it can happen
if the b-tree root node read from a device is configured that way, so fix
this potential issue by adding a check for that case.
In the Linux kernel, the following vulnerability has been resolved:
PCI: kirin: Fix buffer overflow in kirin_pcie_parse_port()
Within kirin_pcie_parse_port(), the pcie->num_slots is compared to
pcie->gpio_id_reset size (MAX_PCI_SLOTS) which is correct and would lead
to an overflow.
Thus, fix condition to pcie->num_slots + 1 >= MAX_PCI_SLOTS and move
pcie->num_slots increment below the if-statement to avoid out-of-bounds
array access.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
[kwilczynski: commit log]
In the Linux kernel, the following vulnerability has been resolved:
RDMA/hns: Fix Use-After-Free of rsv_qp on HIP08
Currently rsv_qp is freed before ib_unregister_device() is called
on HIP08. During the time interval, users can still dereg MR and
rsv_qp will be used in this process, leading to a UAF. Move the
release of rsv_qp after calling ib_unregister_device() to fix it.
In the Linux kernel, the following vulnerability has been resolved:
vhost_vdpa: assign irq bypass producer token correctly
We used to call irq_bypass_unregister_producer() in
vhost_vdpa_setup_vq_irq() which is problematic as we don't know if the
token pointer is still valid or not.
Actually, we use the eventfd_ctx as the token so the life cycle of the
token should be bound to the VHOST_SET_VRING_CALL instead of
vhost_vdpa_setup_vq_irq() which could be called by set_status().
Fixing this by setting up irq bypass producer's token when handling
VHOST_SET_VRING_CALL and un-registering the producer before calling
vhost_vring_ioctl() to prevent a possible use after free as eventfd
could have been released in vhost_vring_ioctl(). And such registering
and unregistering will only be done if DRIVER_OK is set.
In the Linux kernel, the following vulnerability has been resolved:
net: seeq: Fix use after free vulnerability in ether3 Driver Due to Race Condition
In the ether3_probe function, a timer is initialized with a callback
function ether3_ledoff, bound to &prev(dev)->timer. Once the timer is
started, there is a risk of a race condition if the module or device
is removed, triggering the ether3_remove function to perform cleanup.
The sequence of operations that may lead to a UAF bug is as follows:
CPU0 CPU1
| ether3_ledoff
ether3_remove |
free_netdev(dev); |
put_devic |
kfree(dev); |
| ether3_outw(priv(dev)->regs.config2 |= CFG2_CTRLO, REG_CONFIG2);
| // use dev
Fix it by ensuring that the timer is canceled before proceeding with
the cleanup in ether3_remove.
In the Linux kernel, the following vulnerability has been resolved:
mm: call the security_mmap_file() LSM hook in remap_file_pages()
The remap_file_pages syscall handler calls do_mmap() directly, which
doesn't contain the LSM security check. And if the process has called
personality(READ_IMPLIES_EXEC) before and remap_file_pages() is called for
RW pages, this will actually result in remapping the pages to RWX,
bypassing a W^X policy enforced by SELinux.
So we should check prot by security_mmap_file LSM hook in the
remap_file_pages syscall handler before do_mmap() is called. Otherwise, it
potentially permits an attacker to bypass a W^X policy enforced by
SELinux.
The bypass is similar to CVE-2016-10044, which bypass the same thing via
AIO and can be found in [1].
The PoC:
$ cat > test.c
int main(void) {
size_t pagesz = sysconf(_SC_PAGE_SIZE);
int mfd = syscall(SYS_memfd_create, "test", 0);
const char *buf = mmap(NULL, 4 * pagesz, PROT_READ | PROT_WRITE,
MAP_SHARED, mfd, 0);
unsigned int old = syscall(SYS_personality, 0xffffffff);
syscall(SYS_personality, READ_IMPLIES_EXEC | old);
syscall(SYS_remap_file_pages, buf, pagesz, 0, 2, 0);
syscall(SYS_personality, old);
// show the RWX page exists even if W^X policy is enforced
int fd = open("/proc/self/maps", O_RDONLY);
unsigned char buf2[1024];
while (1) {
int ret = read(fd, buf2, 1024);
if (ret <= 0) break;
write(1, buf2, ret);
}
close(fd);
}
$ gcc test.c -o test
$ ./test | grep rwx
7f1836c34000-7f1836c35000 rwxs 00002000 00:01 2050 /memfd:test (deleted)
[PM: subject line tweaks]
In the Linux kernel, the following vulnerability has been resolved:
firmware_loader: Block path traversal
Most firmware names are hardcoded strings, or are constructed from fairly
constrained format strings where the dynamic parts are just some hex
numbers or such.
However, there are a couple codepaths in the kernel where firmware file
names contain string components that are passed through from a device or
semi-privileged userspace; the ones I could find (not counting interfaces
that require root privileges) are:
- lpfc_sli4_request_firmware_update() seems to construct the firmware
filename from "ModelName", a string that was previously parsed out of
some descriptor ("Vital Product Data") in lpfc_fill_vpd()
- nfp_net_fw_find() seems to construct a firmware filename from a model
name coming from nfp_hwinfo_lookup(pf->hwinfo, "nffw.partno"), which I
think parses some descriptor that was read from the device.
(But this case likely isn't exploitable because the format string looks
like "netronome/nic_%s", and there shouldn't be any *folders* starting
with "netronome/nic_". The previous case was different because there,
the "%s" is *at the start* of the format string.)
- module_flash_fw_schedule() is reachable from the
ETHTOOL_MSG_MODULE_FW_FLASH_ACT netlink command, which is marked as
GENL_UNS_ADMIN_PERM (meaning CAP_NET_ADMIN inside a user namespace is
enough to pass the privilege check), and takes a userspace-provided
firmware name.
(But I think to reach this case, you need to have CAP_NET_ADMIN over a
network namespace that a special kind of ethernet device is mapped into,
so I think this is not a viable attack path in practice.)
Fix it by rejecting any firmware names containing ".." path components.
For what it's worth, I went looking and haven't found any USB device
drivers that use the firmware loader dangerously.
In the Linux kernel, the following vulnerability has been resolved:
crypto: hisilicon/qm - inject error before stopping queue
The master ooo cannot be completely closed when the
accelerator core reports memory error. Therefore, the driver
needs to inject the qm error to close the master ooo. Currently,
the qm error is injected after stopping queue, memory may be
released immediately after stopping queue, causing the device to
access the released memory. Therefore, error is injected to close master
ooo before stopping queue to ensure that the device does not access
the released memory.
In the Linux kernel, the following vulnerability has been resolved:
x86/tdx: Fix "in-kernel MMIO" check
TDX only supports kernel-initiated MMIO operations. The handle_mmio()
function checks if the #VE exception occurred in the kernel and rejects
the operation if it did not.
However, userspace can deceive the kernel into performing MMIO on its
behalf. For example, if userspace can point a syscall to an MMIO address,
syscall does get_user() or put_user() on it, triggering MMIO #VE. The
kernel will treat the #VE as in-kernel MMIO.
Ensure that the target MMIO address is within the kernel before decoding
instruction.
In the Linux kernel, the following vulnerability has been resolved:
jfs: fix out-of-bounds in dbNextAG() and diAlloc()
In dbNextAG() , there is no check for the case where bmp->db_numag is
greater or same than MAXAG due to a polluted image, which causes an
out-of-bounds. Therefore, a bounds check should be added in dbMount().
And in dbNextAG(), a check for the case where agpref is greater than
bmp->db_numag should be added, so an out-of-bounds exception should be
prevented.
Additionally, a check for the case where agno is greater or same than
MAXAG should be added in diAlloc() to prevent out-of-bounds.
In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw88: always wait for both firmware loading attempts
In 'rtw_wait_firmware_completion()', always wait for both (regular and
wowlan) firmware loading attempts. Otherwise if 'rtw_usb_intf_init()'
has failed in 'rtw_usb_probe()', 'rtw_usb_disconnect()' may issue
'ieee80211_free_hw()' when one of 'rtw_load_firmware_cb()' (usually
the wowlan one) is still in progress, causing UAF detected by KASAN.
In the Linux kernel, the following vulnerability has been resolved:
drivers: media: dvb-frontends/rtl2832: fix an out-of-bounds write error
Ensure index in rtl2832_pid_filter does not exceed 31 to prevent
out-of-bounds access.
dev->filters is a 32-bit value, so set_bit and clear_bit functions should
only operate on indices from 0 to 31. If index is 32, it will attempt to
access a non-existent 33rd bit, leading to out-of-bounds access.
Change the boundary check from index > 32 to index >= 32 to resolve this
issue.
[hverkuil: added fixes tag, rtl2830_pid_filter -> rtl2832_pid_filter in logmsg]
In the Linux kernel, the following vulnerability has been resolved:
drivers: media: dvb-frontends/rtl2830: fix an out-of-bounds write error
Ensure index in rtl2830_pid_filter does not exceed 31 to prevent
out-of-bounds access.
dev->filters is a 32-bit value, so set_bit and clear_bit functions should
only operate on indices from 0 to 31. If index is 32, it will attempt to
access a non-existent 33rd bit, leading to out-of-bounds access.
Change the boundary check from index > 32 to index >= 32 to resolve this
issue.
In the Linux kernel, the following vulnerability has been resolved:
RDMA/iwcm: Fix WARNING:at_kernel/workqueue.c:#check_flush_dependency
In the commit aee2424246f9 ("RDMA/iwcm: Fix a use-after-free related to
destroying CM IDs"), the function flush_workqueue is invoked to flush the
work queue iwcm_wq.
But at that time, the work queue iwcm_wq was created via the function
alloc_ordered_workqueue without the flag WQ_MEM_RECLAIM.
Because the current process is trying to flush the whole iwcm_wq, if
iwcm_wq doesn't have the flag WQ_MEM_RECLAIM, verify that the current
process is not reclaiming memory or running on a workqueue which doesn't
have the flag WQ_MEM_RECLAIM as that can break forward-progress guarantee
leading to a deadlock.
The call trace is as below:
[ 125.350876][ T1430] Call Trace:
[ 125.356281][ T1430] <TASK>
[ 125.361285][ T1430] ? __warn (kernel/panic.c:693)
[ 125.367640][ T1430] ? check_flush_dependency (kernel/workqueue.c:3706 (discriminator 9))
[ 125.375689][ T1430] ? report_bug (lib/bug.c:180 lib/bug.c:219)
[ 125.382505][ T1430] ? handle_bug (arch/x86/kernel/traps.c:239)
[ 125.388987][ T1430] ? exc_invalid_op (arch/x86/kernel/traps.c:260 (discriminator 1))
[ 125.395831][ T1430] ? asm_exc_invalid_op (arch/x86/include/asm/idtentry.h:621)
[ 125.403125][ T1430] ? check_flush_dependency (kernel/workqueue.c:3706 (discriminator 9))
[ 125.410984][ T1430] ? check_flush_dependency (kernel/workqueue.c:3706 (discriminator 9))
[ 125.418764][ T1430] __flush_workqueue (kernel/workqueue.c:3970)
[ 125.426021][ T1430] ? __pfx___might_resched (kernel/sched/core.c:10151)
[ 125.433431][ T1430] ? destroy_cm_id (drivers/infiniband/core/iwcm.c:375) iw_cm
[ 125.441209][ T1430] ? __pfx___flush_workqueue (kernel/workqueue.c:3910)
[ 125.473900][ T1430] ? _raw_spin_lock_irqsave (arch/x86/include/asm/atomic.h:107 include/linux/atomic/atomic-arch-fallback.h:2170 include/linux/atomic/atomic-instrumented.h:1302 include/asm-generic/qspinlock.h:111 include/linux/spinlock.h:187 include/linux/spinlock_api_smp.h:111 kernel/locking/spinlock.c:162)
[ 125.473909][ T1430] ? __pfx__raw_spin_lock_irqsave (kernel/locking/spinlock.c:161)
[ 125.482537][ T1430] _destroy_id (drivers/infiniband/core/cma.c:2044) rdma_cm
[ 125.495072][ T1430] nvme_rdma_free_queue (drivers/nvme/host/rdma.c:656 drivers/nvme/host/rdma.c:650) nvme_rdma
[ 125.505827][ T1430] nvme_rdma_reset_ctrl_work (drivers/nvme/host/rdma.c:2180) nvme_rdma
[ 125.505831][ T1430] process_one_work (kernel/workqueue.c:3231)
[ 125.515122][ T1430] worker_thread (kernel/workqueue.c:3306 kernel/workqueue.c:3393)
[ 125.515127][ T1430] ? __pfx_worker_thread (kernel/workqueue.c:3339)
[ 125.531837][ T1430] kthread (kernel/kthread.c:389)
[ 125.539864][ T1430] ? __pfx_kthread (kernel/kthread.c:342)
[ 125.550628][ T1430] ret_from_fork (arch/x86/kernel/process.c:147)
[ 125.558840][ T1430] ? __pfx_kthread (kernel/kthread.c:342)
[ 125.558844][ T1430] ret_from_fork_asm (arch/x86/entry/entry_64.S:257)
[ 125.566487][ T1430] </TASK>
[ 125.566488][ T1430] ---[ end trace 0000000000000000 ]---
In the Linux kernel, the following vulnerability has been resolved:
RDMA/rtrs-clt: Reset cid to con_num - 1 to stay in bounds
In the function init_conns(), after the create_con() and create_cm() for
loop if something fails. In the cleanup for loop after the destroy tag, we
access out of bound memory because cid is set to clt_path->s.con_num.
This commits resets the cid to clt_path->s.con_num - 1, to stay in bounds
in the cleanup loop later.
In the Linux kernel, the following vulnerability has been resolved:
ep93xx: clock: Fix off by one in ep93xx_div_recalc_rate()
The psc->div[] array has psc->num_div elements. These values come from
when we call clk_hw_register_div(). It's adc_divisors and
ARRAY_SIZE(adc_divisors)) and so on. So this condition needs to be >=
instead of > to prevent an out of bounds read.