Security Vulnerabilities
- CVEs Published In February 2025
In the Linux kernel, the following vulnerability has been resolved:
ALSA: pcm: Fix races among concurrent hw_params and hw_free calls
Currently we have neither proper check nor protection against the
concurrent calls of PCM hw_params and hw_free ioctls, which may result
in a UAF. Since the existing PCM stream lock can't be used for
protecting the whole ioctl operations, we need a new mutex to protect
those racy calls.
This patch introduced a new mutex, runtime->buffer_mutex, and applies
it to both hw_params and hw_free ioctl code paths. Along with it, the
both functions are slightly modified (the mmap_count check is moved
into the state-check block) for code simplicity.
In the Linux kernel, the following vulnerability has been resolved:
cifs: prevent bad output lengths in smb2_ioctl_query_info()
When calling smb2_ioctl_query_info() with
smb_query_info::flags=PASSTHRU_FSCTL and
smb_query_info::output_buffer_length=0, the following would return
0x10
buffer = memdup_user(arg + sizeof(struct smb_query_info),
qi.output_buffer_length);
if (IS_ERR(buffer)) {
kfree(vars);
return PTR_ERR(buffer);
}
rather than a valid pointer thus making IS_ERR() check fail. This
would then cause a NULL ptr deference in @buffer when accessing it
later in smb2_ioctl_query_ioctl(). While at it, prevent having a
@buffer smaller than 8 bytes to correctly handle SMB2_SET_INFO
FileEndOfFileInformation requests when
smb_query_info::flags=PASSTHRU_SET_INFO.
Here is a small C reproducer which triggers a NULL ptr in @buffer when
passing an invalid smb_query_info::flags
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#define die(s) perror(s), exit(1)
#define QUERY_INFO 0xc018cf07
int main(int argc, char *argv[])
{
int fd;
if (argc < 2)
exit(1);
fd = open(argv[1], O_RDONLY);
if (fd == -1)
die("open");
if (ioctl(fd, QUERY_INFO, (uint32_t[]) { 0, 0, 0, 4, 0, 0}) == -1)
die("ioctl");
close(fd);
return 0;
}
mount.cifs //srv/share /mnt -o ...
gcc repro.c && ./a.out /mnt/f0
[ 114.138620] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI
[ 114.139310] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
[ 114.139775] CPU: 2 PID: 995 Comm: a.out Not tainted 5.17.0-rc8 #1
[ 114.140148] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014
[ 114.140818] RIP: 0010:smb2_ioctl_query_info+0x206/0x410 [cifs]
[ 114.141221] Code: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 c8 01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 7b 28 4c 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 9c 01 00 00 49 8b 3f e8 58 02 fb ff 48 8b 14 24
[ 114.142348] RSP: 0018:ffffc90000b47b00 EFLAGS: 00010256
[ 114.142692] RAX: dffffc0000000000 RBX: ffff888115503200 RCX: ffffffffa020580d
[ 114.143119] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffffa043a380
[ 114.143544] RBP: ffff888115503278 R08: 0000000000000001 R09: 0000000000000003
[ 114.143983] R10: fffffbfff4087470 R11: 0000000000000001 R12: ffff888115503288
[ 114.144424] R13: 00000000ffffffea R14: ffff888115503228 R15: 0000000000000000
[ 114.144852] FS: 00007f7aeabdf740(0000) GS:ffff888151600000(0000) knlGS:0000000000000000
[ 114.145338] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 114.145692] CR2: 00007f7aeacfdf5e CR3: 000000012000e000 CR4: 0000000000350ee0
[ 114.146131] Call Trace:
[ 114.146291] <TASK>
[ 114.146432] ? smb2_query_reparse_tag+0x890/0x890 [cifs]
[ 114.146800] ? cifs_mapchar+0x460/0x460 [cifs]
[ 114.147121] ? rcu_read_lock_sched_held+0x3f/0x70
[ 114.147412] ? cifs_strndup_to_utf16+0x15b/0x250 [cifs]
[ 114.147775] ? dentry_path_raw+0xa6/0xf0
[ 114.148024] ? cifs_convert_path_to_utf16+0x198/0x220 [cifs]
[ 114.148413] ? smb2_check_message+0x1080/0x1080 [cifs]
[ 114.148766] ? rcu_read_lock_sched_held+0x3f/0x70
[ 114.149065] cifs_ioctl+0x1577/0x3320 [cifs]
[ 114.149371] ? lock_downgrade+0x6f0/0x6f0
[ 114.149631] ? cifs_readdir+0x2e60/0x2e60 [cifs]
[ 114.149956] ? rcu_read_lock_sched_held+0x3f/0x70
[ 114.150250] ? __rseq_handle_notify_resume+0x80b/0xbe0
[ 114.150562] ? __up_read+0x192/0x710
[ 114.150791] ? __ia32_sys_rseq+0xf0/0xf0
[ 114.151025] ? __x64_sys_openat+0x11f/0x1d0
[ 114.151296] __x64_sys_ioctl+0x127/0x190
[ 114.151549] do_syscall_64+0x3b/0x90
[ 114.151768] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 114.152079] RIP: 0033:0x7f7aead043df
[ 114.152306] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
ALSA: pcm: Fix potential AB/BA lock with buffer_mutex and mmap_lock
syzbot caught a potential deadlock between the PCM
runtime->buffer_mutex and the mm->mmap_lock. It was brought by the
recent fix to cover the racy read/write and other ioctls, and in that
commit, I overlooked a (hopefully only) corner case that may take the
revert lock, namely, the OSS mmap. The OSS mmap operation
exceptionally allows to re-configure the parameters inside the OSS
mmap syscall, where mm->mmap_mutex is already held. Meanwhile, the
copy_from/to_user calls at read/write operations also take the
mm->mmap_lock internally, hence it may lead to a AB/BA deadlock.
A similar problem was already seen in the past and we fixed it with a
refcount (in commit b248371628aa). The former fix covered only the
call paths with OSS read/write and OSS ioctls, while we need to cover
the concurrent access via both ALSA and OSS APIs now.
This patch addresses the problem above by replacing the buffer_mutex
lock in the read/write operations with a refcount similar as we've
used for OSS. The new field, runtime->buffer_accessing, keeps the
number of concurrent read/write operations. Unlike the former
buffer_mutex protection, this protects only around the
copy_from/to_user() calls; the other codes are basically protected by
the PCM stream lock. The refcount can be a negative, meaning blocked
by the ioctls. If a negative value is seen, the read/write aborts
with -EBUSY. In the ioctl side, OTOH, they check this refcount, too,
and set to a negative value for blocking unless it's already being
accessed.
In the Linux kernel, the following vulnerability has been resolved:
rtc: pl031: fix rtc features null pointer dereference
When there is no interrupt line, rtc alarm feature is disabled.
The clearing of the alarm feature bit was being done prior to allocations
of ldata->rtc device, resulting in a null pointer dereference.
Clear RTC_FEATURE_ALARM after the rtc device is allocated.
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix crash when mount with quota enabled
There is a reported crash when mounting ocfs2 with quota enabled.
RIP: 0010:ocfs2_qinfo_lock_res_init+0x44/0x50 [ocfs2]
Call Trace:
ocfs2_local_read_info+0xb9/0x6f0 [ocfs2]
dquot_load_quota_sb+0x216/0x470
dquot_load_quota_inode+0x85/0x100
ocfs2_enable_quotas+0xa0/0x1c0 [ocfs2]
ocfs2_fill_super.cold+0xc8/0x1bf [ocfs2]
mount_bdev+0x185/0x1b0
legacy_get_tree+0x27/0x40
vfs_get_tree+0x25/0xb0
path_mount+0x465/0xac0
__x64_sys_mount+0x103/0x140
It is caused by when initializing dqi_gqlock, the corresponding dqi_type
and dqi_sb are not properly initialized.
This issue is introduced by commit 6c85c2c72819, which wants to avoid
accessing uninitialized variables in error cases. So make global quota
info properly initialized.
In the Linux kernel, the following vulnerability has been resolved:
can: m_can: m_can_tx_handler(): fix use after free of skb
can_put_echo_skb() will clone skb then free the skb. Move the
can_put_echo_skb() for the m_can version 3.0.x directly before the
start of the xmit in hardware, similar to the 3.1.x branch.
In the Linux kernel, the following vulnerability has been resolved:
jffs2: fix memory leak in jffs2_scan_medium
If an error is returned in jffs2_scan_eraseblock() and some memory
has been added to the jffs2_summary *s, we can observe the following
kmemleak report:
--------------------------------------------
unreferenced object 0xffff88812b889c40 (size 64):
comm "mount", pid 692, jiffies 4294838325 (age 34.288s)
hex dump (first 32 bytes):
40 48 b5 14 81 88 ff ff 01 e0 31 00 00 00 50 00 @H........1...P.
00 00 01 00 00 00 01 00 00 00 02 00 00 00 09 08 ................
backtrace:
[<ffffffffae93a3a3>] __kmalloc+0x613/0x910
[<ffffffffaf423b9c>] jffs2_sum_add_dirent_mem+0x5c/0xa0
[<ffffffffb0f3afa8>] jffs2_scan_medium.cold+0x36e5/0x4794
[<ffffffffb0f3dbe1>] jffs2_do_mount_fs.cold+0xa7/0x2267
[<ffffffffaf40acf3>] jffs2_do_fill_super+0x383/0xc30
[<ffffffffaf40c00a>] jffs2_fill_super+0x2ea/0x4c0
[<ffffffffb0315d64>] mtd_get_sb+0x254/0x400
[<ffffffffb0315f5f>] mtd_get_sb_by_nr+0x4f/0xd0
[<ffffffffb0316478>] get_tree_mtd+0x498/0x840
[<ffffffffaf40bd15>] jffs2_get_tree+0x25/0x30
[<ffffffffae9f358d>] vfs_get_tree+0x8d/0x2e0
[<ffffffffaea7a98f>] path_mount+0x50f/0x1e50
[<ffffffffaea7c3d7>] do_mount+0x107/0x130
[<ffffffffaea7c5c5>] __se_sys_mount+0x1c5/0x2f0
[<ffffffffaea7c917>] __x64_sys_mount+0xc7/0x160
[<ffffffffb10142f5>] do_syscall_64+0x45/0x70
unreferenced object 0xffff888114b54840 (size 32):
comm "mount", pid 692, jiffies 4294838325 (age 34.288s)
hex dump (first 32 bytes):
c0 75 b5 14 81 88 ff ff 02 e0 02 00 00 00 02 00 .u..............
00 00 84 00 00 00 44 00 00 00 6b 6b 6b 6b 6b a5 ......D...kkkkk.
backtrace:
[<ffffffffae93be24>] kmem_cache_alloc_trace+0x584/0x880
[<ffffffffaf423b04>] jffs2_sum_add_inode_mem+0x54/0x90
[<ffffffffb0f3bd44>] jffs2_scan_medium.cold+0x4481/0x4794
[...]
unreferenced object 0xffff888114b57280 (size 32):
comm "mount", pid 692, jiffies 4294838393 (age 34.357s)
hex dump (first 32 bytes):
10 d5 6c 11 81 88 ff ff 08 e0 05 00 00 00 01 00 ..l.............
00 00 38 02 00 00 28 00 00 00 6b 6b 6b 6b 6b a5 ..8...(...kkkkk.
backtrace:
[<ffffffffae93be24>] kmem_cache_alloc_trace+0x584/0x880
[<ffffffffaf423c34>] jffs2_sum_add_xattr_mem+0x54/0x90
[<ffffffffb0f3a24f>] jffs2_scan_medium.cold+0x298c/0x4794
[...]
unreferenced object 0xffff8881116cd510 (size 16):
comm "mount", pid 692, jiffies 4294838395 (age 34.355s)
hex dump (first 16 bytes):
00 00 00 00 00 00 00 00 09 e0 60 02 00 00 6b a5 ..........`...k.
backtrace:
[<ffffffffae93be24>] kmem_cache_alloc_trace+0x584/0x880
[<ffffffffaf423cc4>] jffs2_sum_add_xref_mem+0x54/0x90
[<ffffffffb0f3b2e3>] jffs2_scan_medium.cold+0x3a20/0x4794
[...]
--------------------------------------------
Therefore, we should call jffs2_sum_reset_collected(s) on exit to
release the memory added in s. In addition, a new tag "out_buf" is
added to prevent the NULL pointer reference caused by s being NULL.
(thanks to Zhang Yi for this analysis)
In the Linux kernel, the following vulnerability has been resolved:
jffs2: fix memory leak in jffs2_do_mount_fs
If jffs2_build_filesystem() in jffs2_do_mount_fs() returns an error,
we can observe the following kmemleak report:
--------------------------------------------
unreferenced object 0xffff88811b25a640 (size 64):
comm "mount", pid 691, jiffies 4294957728 (age 71.952s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 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:
[<ffffffffa493be24>] kmem_cache_alloc_trace+0x584/0x880
[<ffffffffa5423a06>] jffs2_sum_init+0x86/0x130
[<ffffffffa5400e58>] jffs2_do_mount_fs+0x798/0xac0
[<ffffffffa540acf3>] jffs2_do_fill_super+0x383/0xc30
[<ffffffffa540c00a>] jffs2_fill_super+0x2ea/0x4c0
[...]
unreferenced object 0xffff88812c760000 (size 65536):
comm "mount", pid 691, jiffies 4294957728 (age 71.952s)
hex dump (first 32 bytes):
bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................
backtrace:
[<ffffffffa493a449>] __kmalloc+0x6b9/0x910
[<ffffffffa5423a57>] jffs2_sum_init+0xd7/0x130
[<ffffffffa5400e58>] jffs2_do_mount_fs+0x798/0xac0
[<ffffffffa540acf3>] jffs2_do_fill_super+0x383/0xc30
[<ffffffffa540c00a>] jffs2_fill_super+0x2ea/0x4c0
[...]
--------------------------------------------
This is because the resources allocated in jffs2_sum_init() are not
released. Call jffs2_sum_exit() to release these resources to solve
the problem.
In the Linux kernel, the following vulnerability has been resolved:
remoteproc: Fix count check in rproc_coredump_write()
Check count for 0, to avoid a potential underflow. Make the check the
same as the one in rproc_recovery_write().
In the Linux kernel, the following vulnerability has been resolved:
NFSD: prevent integer overflow on 32 bit systems
On a 32 bit system, the "len * sizeof(*p)" operation can have an
integer overflow.