| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
md/raid10: fix memleak of md thread
In raid10_run(), if setup_conf() succeed and raid10_run() failed before
setting 'mddev->thread', then in the error path 'conf->thread' is not
freed.
Fix the problem by setting 'mddev->thread' right after setup_conf(). |
| In the Linux kernel, the following vulnerability has been resolved:
nvmem: core: Fix memleak in nvmem_register()
dev_set_name will alloc memory for nvmem->dev.kobj.name in
nvmem_register, when nvmem_validate_keepouts failed, nvmem's
memory will be freed and return, but nobody will free memory
for nvmem->dev.kobj.name, there will be memleak, so moving
nvmem_validate_keepouts() after device_register() and let
the device core deal with cleaning name in error cases. |
| In the Linux kernel, the following vulnerability has been resolved:
block, bfq: Fix division by zero error on zero wsum
When the weighted sum is zero the calculation of limit causes
a division by zero error. Fix this by continuing to the next level.
This was discovered by running as root:
stress-ng --ioprio 0
Fixes divison by error oops:
[ 521.450556] divide error: 0000 [#1] SMP NOPTI
[ 521.450766] CPU: 2 PID: 2684464 Comm: stress-ng-iopri Not tainted 6.2.1-1280.native #1
[ 521.451117] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.1-0-g3208b098f51a-prebuilt.qemu.org 04/01/2014
[ 521.451627] RIP: 0010:bfqq_request_over_limit+0x207/0x400
[ 521.451875] Code: 01 48 8d 0c c8 74 0b 48 8b 82 98 00 00 00 48 8d 0c c8 8b 85 34 ff ff ff 48 89 ca 41 0f af 41 50 48 d1 ea 48 98 48 01 d0 31 d2 <48> f7 f1 41 39 41 48 89 85 34 ff ff ff 0f 8c 7b 01 00 00 49 8b 44
[ 521.452699] RSP: 0018:ffffb1af84eb3948 EFLAGS: 00010046
[ 521.452938] RAX: 000000000000003c RBX: 0000000000000000 RCX: 0000000000000000
[ 521.453262] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb1af84eb3978
[ 521.453584] RBP: ffffb1af84eb3a30 R08: 0000000000000001 R09: ffff8f88ab8a4ba0
[ 521.453905] R10: 0000000000000000 R11: 0000000000000001 R12: ffff8f88ab8a4b18
[ 521.454224] R13: ffff8f8699093000 R14: 0000000000000001 R15: ffffb1af84eb3970
[ 521.454549] FS: 00005640b6b0b580(0000) GS:ffff8f88b3880000(0000) knlGS:0000000000000000
[ 521.454912] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 521.455170] CR2: 00007ffcbcae4e38 CR3: 00000002e46de001 CR4: 0000000000770ee0
[ 521.455491] PKRU: 55555554
[ 521.455619] Call Trace:
[ 521.455736] <TASK>
[ 521.455837] ? bfq_request_merge+0x3a/0xc0
[ 521.456027] ? elv_merge+0x115/0x140
[ 521.456191] bfq_limit_depth+0xc8/0x240
[ 521.456366] __blk_mq_alloc_requests+0x21a/0x2c0
[ 521.456577] blk_mq_submit_bio+0x23c/0x6c0
[ 521.456766] __submit_bio+0xb8/0x140
[ 521.457236] submit_bio_noacct_nocheck+0x212/0x300
[ 521.457748] submit_bio_noacct+0x1a6/0x580
[ 521.458220] submit_bio+0x43/0x80
[ 521.458660] ext4_io_submit+0x23/0x80
[ 521.459116] ext4_do_writepages+0x40a/0xd00
[ 521.459596] ext4_writepages+0x65/0x100
[ 521.460050] do_writepages+0xb7/0x1c0
[ 521.460492] __filemap_fdatawrite_range+0xa6/0x100
[ 521.460979] file_write_and_wait_range+0xbf/0x140
[ 521.461452] ext4_sync_file+0x105/0x340
[ 521.461882] __x64_sys_fsync+0x67/0x100
[ 521.462305] ? syscall_exit_to_user_mode+0x2c/0x1c0
[ 521.462768] do_syscall_64+0x3b/0xc0
[ 521.463165] entry_SYSCALL_64_after_hwframe+0x5a/0xc4
[ 521.463621] RIP: 0033:0x5640b6c56590
[ 521.464006] Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 80 3d 71 70 0e 00 00 74 17 b8 4a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: Fix memory leak in ath11k_peer_rx_frag_setup
crypto_alloc_shash() allocates resources, which should be released by
crypto_free_shash(). When ath11k_peer_find() fails, there has memory
leak. Add missing crypto_free_shash() to fix this. |
| In the Linux kernel, the following vulnerability has been resolved:
misc: ocxl: fix possible refcount leak in afu_ioctl()
eventfd_ctx_put need to be called to put the refcount that gotten by
eventfd_ctx_fdget when ocxl_irq_set_handler fails. |
| In the Linux kernel, the following vulnerability has been resolved:
staging: media: tegra-video: fix device_node use after free
At probe time this code path is followed:
* tegra_csi_init
* tegra_csi_channels_alloc
* for_each_child_of_node(node, channel) -- iterates over channels
* automatically gets 'channel'
* tegra_csi_channel_alloc()
* saves into chan->of_node a pointer to the channel OF node
* automatically gets and puts 'channel'
* now the node saved in chan->of_node has refcount 0, can disappear
* tegra_csi_channels_init
* iterates over channels
* tegra_csi_channel_init -- uses chan->of_node
After that, chan->of_node keeps storing the node until the device is
removed.
of_node_get() the node and of_node_put() it during teardown to avoid any
risk. |
| In the Linux kernel, the following vulnerability has been resolved:
media: camss: Clean up received buffers on failed start of streaming
It is required to return the received buffers, if streaming can not be
started. For instance media_pipeline_start() may fail with EPIPE, if
a link validation between entities is not passed, and in such a case
a user gets a kernel warning:
WARNING: CPU: 1 PID: 520 at drivers/media/common/videobuf2/videobuf2-core.c:1592 vb2_start_streaming+0xec/0x160
<snip>
Call trace:
vb2_start_streaming+0xec/0x160
vb2_core_streamon+0x9c/0x1a0
vb2_ioctl_streamon+0x68/0xbc
v4l_streamon+0x30/0x3c
__video_do_ioctl+0x184/0x3e0
video_usercopy+0x37c/0x7b0
video_ioctl2+0x24/0x40
v4l2_ioctl+0x4c/0x70
The fix is to correct the error path in video_start_streaming() of camss. |
| In the Linux kernel, the following vulnerability has been resolved:
RISC-V: kexec: Fix memory leak of elf header buffer
This is reported by kmemleak detector:
unreferenced object 0xff2000000403d000 (size 4096):
comm "kexec", pid 146, jiffies 4294900633 (age 64.792s)
hex dump (first 32 bytes):
7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00 .ELF............
04 00 f3 00 01 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000566ca97c>] kmemleak_vmalloc+0x3c/0xbe
[<00000000979283d8>] __vmalloc_node_range+0x3ac/0x560
[<00000000b4b3712a>] __vmalloc_node+0x56/0x62
[<00000000854f75e2>] vzalloc+0x2c/0x34
[<00000000e9a00db9>] crash_prepare_elf64_headers+0x80/0x30c
[<0000000067e8bf48>] elf_kexec_load+0x3e8/0x4ec
[<0000000036548e09>] kexec_image_load_default+0x40/0x4c
[<0000000079fbe1b4>] sys_kexec_file_load+0x1c4/0x322
[<0000000040c62c03>] ret_from_syscall+0x0/0x2
In elf_kexec_load(), a buffer is allocated via vzalloc() to store elf
headers. While it's not freed back to system when kdump kernel is
reloaded or unloaded, or when image->elf_header is successfully set and
then fails to load kdump kernel for some reason. Fix it by freeing the
buffer in arch_kimage_file_post_load_cleanup(). |
| In the Linux kernel, the following vulnerability has been resolved:
amdgpu/pm: prevent array underflow in vega20_odn_edit_dpm_table()
In the PP_OD_EDIT_VDDC_CURVE case the "input_index" variable is capped at
2 but not checked for negative values so it results in an out of bounds
read. This value comes from the user via sysfs. |
| In the Linux kernel, the following vulnerability has been resolved:
hfs: fix KMSAN uninit-value issue in hfs_find_set_zero_bits()
The syzbot reported issue in hfs_find_set_zero_bits():
=====================================================
BUG: KMSAN: uninit-value in hfs_find_set_zero_bits+0x74d/0xb60 fs/hfs/bitmap.c:45
hfs_find_set_zero_bits+0x74d/0xb60 fs/hfs/bitmap.c:45
hfs_vbm_search_free+0x13c/0x5b0 fs/hfs/bitmap.c:151
hfs_extend_file+0x6a5/0x1b00 fs/hfs/extent.c:408
hfs_get_block+0x435/0x1150 fs/hfs/extent.c:353
__block_write_begin_int+0xa76/0x3030 fs/buffer.c:2151
block_write_begin fs/buffer.c:2262 [inline]
cont_write_begin+0x10e1/0x1bc0 fs/buffer.c:2601
hfs_write_begin+0x85/0x130 fs/hfs/inode.c:52
cont_expand_zero fs/buffer.c:2528 [inline]
cont_write_begin+0x35a/0x1bc0 fs/buffer.c:2591
hfs_write_begin+0x85/0x130 fs/hfs/inode.c:52
hfs_file_truncate+0x1d6/0xe60 fs/hfs/extent.c:494
hfs_inode_setattr+0x964/0xaa0 fs/hfs/inode.c:654
notify_change+0x1993/0x1aa0 fs/attr.c:552
do_truncate+0x28f/0x310 fs/open.c:68
do_ftruncate+0x698/0x730 fs/open.c:195
do_sys_ftruncate fs/open.c:210 [inline]
__do_sys_ftruncate fs/open.c:215 [inline]
__se_sys_ftruncate fs/open.c:213 [inline]
__x64_sys_ftruncate+0x11b/0x250 fs/open.c:213
x64_sys_call+0xfe3/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:78
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Uninit was created at:
slab_post_alloc_hook mm/slub.c:4154 [inline]
slab_alloc_node mm/slub.c:4197 [inline]
__kmalloc_cache_noprof+0x7f7/0xed0 mm/slub.c:4354
kmalloc_noprof include/linux/slab.h:905 [inline]
hfs_mdb_get+0x1cc8/0x2a90 fs/hfs/mdb.c:175
hfs_fill_super+0x3d0/0xb80 fs/hfs/super.c:337
get_tree_bdev_flags+0x6e3/0x920 fs/super.c:1681
get_tree_bdev+0x38/0x50 fs/super.c:1704
hfs_get_tree+0x35/0x40 fs/hfs/super.c:388
vfs_get_tree+0xb0/0x5c0 fs/super.c:1804
do_new_mount+0x738/0x1610 fs/namespace.c:3902
path_mount+0x6db/0x1e90 fs/namespace.c:4226
do_mount fs/namespace.c:4239 [inline]
__do_sys_mount fs/namespace.c:4450 [inline]
__se_sys_mount+0x6eb/0x7d0 fs/namespace.c:4427
__x64_sys_mount+0xe4/0x150 fs/namespace.c:4427
x64_sys_call+0xfa7/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:166
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
CPU: 1 UID: 0 PID: 12609 Comm: syz.1.2692 Not tainted 6.16.0-syzkaller #0 PREEMPT(none)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
=====================================================
The HFS_SB(sb)->bitmap buffer is allocated in hfs_mdb_get():
HFS_SB(sb)->bitmap = kmalloc(8192, GFP_KERNEL);
Finally, it can trigger the reported issue because kmalloc()
doesn't clear the allocated memory. If allocated memory contains
only zeros, then everything will work pretty fine.
But if the allocated memory contains the "garbage", then
it can affect the bitmap operations and it triggers
the reported issue.
This patch simply exchanges the kmalloc() on kzalloc()
with the goal to guarantee the correctness of bitmap operations.
Because, newly created allocation bitmap should have all
available blocks free. Potentially, initialization bitmap's read
operation could not fill the whole allocated memory and
"garbage" in the not initialized memory will be the reason of
volume coruptions and file system driver bugs. |
| In the Linux kernel, the following vulnerability has been resolved:
mmc: alcor: fix return value check of mmc_add_host()
mmc_add_host() may return error, if we ignore its return value, the memory
that allocated in mmc_alloc_host() will be leaked and it will lead a kernel
crash because of deleting not added device in the remove path.
So fix this by checking the return value and calling mmc_free_host() in the
error path. |
| 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:
drm/amdgpu: validate userq buffer virtual address and size
It needs to validate the userq object virtual address to
determine whether it is residented in a valid vm mapping. |
| In the Linux kernel, the following vulnerability has been resolved:
hfs: validate record offset in hfsplus_bmap_alloc
hfsplus_bmap_alloc can trigger a crash if a
record offset or length is larger than node_size
[ 15.264282] BUG: KASAN: slab-out-of-bounds in hfsplus_bmap_alloc+0x887/0x8b0
[ 15.265192] Read of size 8 at addr ffff8881085ca188 by task test/183
[ 15.265949]
[ 15.266163] CPU: 0 UID: 0 PID: 183 Comm: test Not tainted 6.17.0-rc2-gc17b750b3ad9 #14 PREEMPT(voluntary)
[ 15.266165] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 15.266167] Call Trace:
[ 15.266168] <TASK>
[ 15.266169] dump_stack_lvl+0x53/0x70
[ 15.266173] print_report+0xd0/0x660
[ 15.266181] kasan_report+0xce/0x100
[ 15.266185] hfsplus_bmap_alloc+0x887/0x8b0
[ 15.266208] hfs_btree_inc_height.isra.0+0xd5/0x7c0
[ 15.266217] hfsplus_brec_insert+0x870/0xb00
[ 15.266222] __hfsplus_ext_write_extent+0x428/0x570
[ 15.266225] __hfsplus_ext_cache_extent+0x5e/0x910
[ 15.266227] hfsplus_ext_read_extent+0x1b2/0x200
[ 15.266233] hfsplus_file_extend+0x5a7/0x1000
[ 15.266237] hfsplus_get_block+0x12b/0x8c0
[ 15.266238] __block_write_begin_int+0x36b/0x12c0
[ 15.266251] block_write_begin+0x77/0x110
[ 15.266252] cont_write_begin+0x428/0x720
[ 15.266259] hfsplus_write_begin+0x51/0x100
[ 15.266262] cont_write_begin+0x272/0x720
[ 15.266270] hfsplus_write_begin+0x51/0x100
[ 15.266274] generic_perform_write+0x321/0x750
[ 15.266285] generic_file_write_iter+0xc3/0x310
[ 15.266289] __kernel_write_iter+0x2fd/0x800
[ 15.266296] dump_user_range+0x2ea/0x910
[ 15.266301] elf_core_dump+0x2a94/0x2ed0
[ 15.266320] vfs_coredump+0x1d85/0x45e0
[ 15.266349] get_signal+0x12e3/0x1990
[ 15.266357] arch_do_signal_or_restart+0x89/0x580
[ 15.266362] irqentry_exit_to_user_mode+0xab/0x110
[ 15.266364] asm_exc_page_fault+0x26/0x30
[ 15.266366] RIP: 0033:0x41bd35
[ 15.266367] Code: bc d1 f3 0f 7f 27 f3 0f 7f 6f 10 f3 0f 7f 77 20 f3 0f 7f 7f 30 49 83 c0 0f 49 29 d0 48 8d 7c 17 31 e9 9f 0b 00 00 66 0f ef c0 <f3> 0f 6f 0e f3 0f 6f 56 10 66 0f 74 c1 66 0f d7 d0 49 83 f8f
[ 15.266369] RSP: 002b:00007ffc9e62d078 EFLAGS: 00010283
[ 15.266371] RAX: 00007ffc9e62d100 RBX: 0000000000000000 RCX: 0000000000000000
[ 15.266372] RDX: 00000000000000e0 RSI: 0000000000000000 RDI: 00007ffc9e62d100
[ 15.266373] RBP: 0000400000000040 R08: 00000000000000e0 R09: 0000000000000000
[ 15.266374] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
[ 15.266375] R13: 0000000000000000 R14: 0000000000000000 R15: 0000400000000000
[ 15.266376] </TASK>
When calling hfsplus_bmap_alloc to allocate a free node, this function
first retrieves the bitmap from header node and map node using node->page
together with the offset and length from hfs_brec_lenoff
```
len = hfs_brec_lenoff(node, 2, &off16);
off = off16;
off += node->page_offset;
pagep = node->page + (off >> PAGE_SHIFT);
data = kmap_local_page(*pagep);
```
However, if the retrieved offset or length is invalid(i.e. exceeds
node_size), the code may end up accessing pages outside the allocated
range for this node.
This patch adds proper validation of both offset and length before use,
preventing out-of-bounds page access. Move is_bnode_offset_valid and
check_and_correct_requested_length to hfsplus_fs.h, as they may be
required by other functions. |
| In the Linux kernel, the following vulnerability has been resolved:
hfs: fix missing hfs_bnode_get() in __hfs_bnode_create
Syzbot found a kernel BUG in hfs_bnode_put():
kernel BUG at fs/hfs/bnode.c:466!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 3634 Comm: kworker/u4:5 Not tainted 6.1.0-rc7-syzkaller-00190-g97ee9d1c1696 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:hfs_bnode_put+0x46f/0x480 fs/hfs/bnode.c:466
Code: 8a 80 ff e9 73 fe ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c a0 fe ff ff 48 89 df e8 db 8a 80 ff e9 93 fe ff ff e8 a1 68 2c ff <0f> 0b e8 9a 68 2c ff 0f 0b 0f 1f 84 00 00 00 00 00 55 41 57 41 56
RSP: 0018:ffffc90003b4f258 EFLAGS: 00010293
RAX: ffffffff825e318f RBX: 0000000000000000 RCX: ffff8880739dd7c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003b4f430 R08: ffffffff825e2d9b R09: ffffed10045157d1
R10: ffffed10045157d1 R11: 1ffff110045157d0 R12: ffff8880228abe80
R13: ffff88807016c000 R14: dffffc0000000000 R15: ffff8880228abe00
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa6ebe88718 CR3: 000000001e93d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
hfs_write_inode+0x1bc/0xb40
write_inode fs/fs-writeback.c:1440 [inline]
__writeback_single_inode+0x4d6/0x670 fs/fs-writeback.c:1652
writeback_sb_inodes+0xb3b/0x18f0 fs/fs-writeback.c:1878
__writeback_inodes_wb+0x125/0x420 fs/fs-writeback.c:1949
wb_writeback+0x440/0x7b0 fs/fs-writeback.c:2054
wb_check_start_all fs/fs-writeback.c:2176 [inline]
wb_do_writeback fs/fs-writeback.c:2202 [inline]
wb_workfn+0x827/0xef0 fs/fs-writeback.c:2235
process_one_work+0x877/0xdb0 kernel/workqueue.c:2289
worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
kthread+0x266/0x300 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>
The BUG_ON() is triggered at here:
/* Dispose of resources used by a node */
void hfs_bnode_put(struct hfs_bnode *node)
{
if (node) {
<skipped>
BUG_ON(!atomic_read(&node->refcnt)); <- we have issue here!!!!
<skipped>
}
}
By tracing the refcnt, I found the node is created by hfs_bmap_alloc()
with refcnt 1. Then the node is used by hfs_btree_write(). There is a
missing of hfs_bnode_get() after find the node. The issue happened in
following path:
<alloc>
hfs_bmap_alloc
hfs_bnode_find
__hfs_bnode_create <- allocate a new node with refcnt 1.
hfs_bnode_put <- decrease the refcnt
<write>
hfs_btree_write
hfs_bnode_find
__hfs_bnode_create
hfs_bnode_findhash <- find the node without refcnt increased.
hfs_bnode_put <- trigger the BUG_ON() since refcnt is 0. |
| In the Linux kernel, the following vulnerability has been resolved:
slab: Avoid race on slab->obj_exts in alloc_slab_obj_exts
If two competing threads enter alloc_slab_obj_exts() and one of them
fails to allocate the object extension vector, it might override the
valid slab->obj_exts allocated by the other thread with
OBJEXTS_ALLOC_FAIL. This will cause the thread that lost this race and
expects a valid pointer to dereference a NULL pointer later on.
Update slab->obj_exts atomically using cmpxchg() to avoid
slab->obj_exts overrides by racing threads.
Thanks for Vlastimil and Suren's help with debugging. |
| In the Linux kernel, the following vulnerability has been resolved:
net: phy: micrel: always set shared->phydev for LAN8814
Currently, during the LAN8814 PTP probe shared->phydev is only set if PTP
clock gets actually set, otherwise the function will return before setting
it.
This is an issue as shared->phydev is unconditionally being used when IRQ
is being handled, especially in lan8814_gpio_process_cap and since it was
not set it will cause a NULL pointer exception and crash the kernel.
So, simply always set shared->phydev to avoid the NULL pointer exception. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: api - Use work queue in crypto_destroy_instance
The function crypto_drop_spawn expects to be called in process
context. However, when an instance is unregistered while it still
has active users, the last user may cause the instance to be freed
in atomic context.
Fix this by delaying the freeing to a work queue. |
| In the Linux kernel, the following vulnerability has been resolved:
net: netpoll: fix incorrect refcount handling causing incorrect cleanup
commit efa95b01da18 ("netpoll: fix use after free") incorrectly
ignored the refcount and prematurely set dev->npinfo to NULL during
netpoll cleanup, leading to improper behavior and memory leaks.
Scenario causing lack of proper cleanup:
1) A netpoll is associated with a NIC (e.g., eth0) and netdev->npinfo is
allocated, and refcnt = 1
- Keep in mind that npinfo is shared among all netpoll instances. In
this case, there is just one.
2) Another netpoll is also associated with the same NIC and
npinfo->refcnt += 1.
- Now dev->npinfo->refcnt = 2;
- There is just one npinfo associated to the netdev.
3) When the first netpolls goes to clean up:
- The first cleanup succeeds and clears np->dev->npinfo, ignoring
refcnt.
- It basically calls `RCU_INIT_POINTER(np->dev->npinfo, NULL);`
- Set dev->npinfo = NULL, without proper cleanup
- No ->ndo_netpoll_cleanup() is either called
4) Now the second target tries to clean up
- The second cleanup fails because np->dev->npinfo is already NULL.
* In this case, ops->ndo_netpoll_cleanup() was never called, and
the skb pool is not cleaned as well (for the second netpoll
instance)
- This leaks npinfo and skbpool skbs, which is clearly reported by
kmemleak.
Revert commit efa95b01da18 ("netpoll: fix use after free") and adds
clarifying comments emphasizing that npinfo cleanup should only happen
once the refcount reaches zero, ensuring stable and correct netpoll
behavior. |
| In the Linux kernel, the following vulnerability has been resolved:
coresight: ETR: Fix ETR buffer use-after-free issue
When ETR is enabled as CS_MODE_SYSFS, if the buffer size is changed
and enabled again, currently sysfs_buf will point to the newly
allocated memory(buf_new) and free the old memory(buf_old). But the
etr_buf that is being used by the ETR remains pointed to buf_old, not
updated to buf_new. In this case, it will result in a memory
use-after-free issue.
Fix this by checking ETR's mode before updating and releasing buf_old,
if the mode is CS_MODE_SYSFS, then skip updating and releasing it. |
