Linux: >> Linux Kernel >> 2.6.15.3 Security Vulnerabilities
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---
CVSS Score
5.5
EPSS Score
0.001
Published
2025-02-26
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)
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26
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.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26
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.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
NFSD: prevent underflow in nfssvc_decode_writeargs()
Smatch complains:
fs/nfsd/nfsxdr.c:341 nfssvc_decode_writeargs()
warn: no lower bound on 'args->len'
Change the type to unsigned to prevent this issue.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
cifs: fix handlecache and multiuser
In multiuser each individual user has their own tcon structure for the
share and thus their own handle for a cached directory.
When we umount such a share we much make sure to release the pinned down dentry
for each such tcon and not just the master tcon.
Otherwise we will get nasty warnings on umount that dentries are still in use:
[ 3459.590047] BUG: Dentry 00000000115c6f41{i=12000000019d95,n=/} still in use\
(2) [unmount of cifs cifs]
...
[ 3459.590492] Call Trace:
[ 3459.590500] d_walk+0x61/0x2a0
[ 3459.590518] ? shrink_lock_dentry.part.0+0xe0/0xe0
[ 3459.590526] shrink_dcache_for_umount+0x49/0x110
[ 3459.590535] generic_shutdown_super+0x1a/0x110
[ 3459.590542] kill_anon_super+0x14/0x30
[ 3459.590549] cifs_kill_sb+0xf5/0x104 [cifs]
[ 3459.590773] deactivate_locked_super+0x36/0xa0
[ 3459.590782] cleanup_mnt+0x131/0x190
[ 3459.590789] task_work_run+0x5c/0x90
[ 3459.590798] exit_to_user_mode_loop+0x151/0x160
[ 3459.590809] exit_to_user_mode_prepare+0x83/0xd0
[ 3459.590818] syscall_exit_to_user_mode+0x12/0x30
[ 3459.590828] do_syscall_64+0x48/0x90
[ 3459.590833] entry_SYSCALL_64_after_hwframe+0x44/0xae
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
exec: Force single empty string when argv is empty
Quoting[1] Ariadne Conill:
"In several other operating systems, it is a hard requirement that the
second argument to execve(2) be the name of a program, thus prohibiting
a scenario where argc < 1. POSIX 2017 also recommends this behaviour,
but it is not an explicit requirement[2]:
The argument arg0 should point to a filename string that is
associated with the process being started by one of the exec
functions.
...
Interestingly, Michael Kerrisk opened an issue about this in 2008[3],
but there was no consensus to support fixing this issue then.
Hopefully now that CVE-2021-4034 shows practical exploitative use[4]
of this bug in a shellcode, we can reconsider.
This issue is being tracked in the KSPP issue tracker[5]."
While the initial code searches[6][7] turned up what appeared to be
mostly corner case tests, trying to that just reject argv == NULL
(or an immediately terminated pointer list) quickly started tripping[8]
existing userspace programs.
The next best approach is forcing a single empty string into argv and
adjusting argc to match. The number of programs depending on argc == 0
seems a smaller set than those calling execve with a NULL argv.
Account for the additional stack space in bprm_stack_limits(). Inject an
empty string when argc == 0 (and set argc = 1). Warn about the case so
userspace has some notice about the change:
process './argc0' launched './argc0' with NULL argv: empty string added
Additionally WARN() and reject NULL argv usage for kernel threads.
[1] https://lore.kernel.org/lkml/20220127000724.15106-1-ariadne@dereferenced.org/
[2] https://pubs.opengroup.org/onlinepubs/9699919799/functions/exec.html
[3] https://bugzilla.kernel.org/show_bug.cgi?id=8408
[4] https://www.qualys.com/2022/01/25/cve-2021-4034/pwnkit.txt
[5] https://github.com/KSPP/linux/issues/176
[6] https://codesearch.debian.net/search?q=execve%5C+*%5C%28%5B%5E%2C%5D%2B%2C+*NULL&literal=0
[7] https://codesearch.debian.net/search?q=execlp%3F%5Cs*%5C%28%5B%5E%2C%5D%2B%2C%5Cs*NULL&literal=0
[8] https://lore.kernel.org/lkml/20220131144352.GE16385@xsang-OptiPlex-9020/
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
mmc: core: use sysfs_emit() instead of sprintf()
sprintf() (still used in the MMC core for the sysfs output) is vulnerable
to the buffer overflow. Use the new-fangled sysfs_emit() instead.
Found by Linux Verification Center (linuxtesting.org) with the SVACE static
analysis tool.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
af_netlink: Fix shift out of bounds in group mask calculation
When a netlink message is received, netlink_recvmsg() fills in the address
of the sender. One of the fields is the 32-bit bitfield nl_groups, which
carries the multicast group on which the message was received. The least
significant bit corresponds to group 1, and therefore the highest group
that the field can represent is 32. Above that, the UB sanitizer flags the
out-of-bounds shift attempts.
Which bits end up being set in such case is implementation defined, but
it's either going to be a wrong non-zero value, or zero, which is at least
not misleading. Make the latter choice deterministic by always setting to 0
for higher-numbered multicast groups.
To get information about membership in groups >= 32, userspace is expected
to use nl_pktinfo control messages[0], which are enabled by NETLINK_PKTINFO
socket option.
[0] https://lwn.net/Articles/147608/
The way to trigger this issue is e.g. through monitoring the BRVLAN group:
# bridge monitor vlan &
# ip link add name br type bridge
Which produces the following citation:
UBSAN: shift-out-of-bounds in net/netlink/af_netlink.c:162:19
shift exponent 32 is too large for 32-bit type 'int'
CVSS Score
5.5
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
block, bfq: don't move oom_bfqq
Our test report a UAF:
[ 2073.019181] ==================================================================
[ 2073.019188] BUG: KASAN: use-after-free in __bfq_put_async_bfqq+0xa0/0x168
[ 2073.019191] Write of size 8 at addr ffff8000ccf64128 by task rmmod/72584
[ 2073.019192]
[ 2073.019196] CPU: 0 PID: 72584 Comm: rmmod Kdump: loaded Not tainted 4.19.90-yk #5
[ 2073.019198] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
[ 2073.019200] Call trace:
[ 2073.019203] dump_backtrace+0x0/0x310
[ 2073.019206] show_stack+0x28/0x38
[ 2073.019210] dump_stack+0xec/0x15c
[ 2073.019216] print_address_description+0x68/0x2d0
[ 2073.019220] kasan_report+0x238/0x2f0
[ 2073.019224] __asan_store8+0x88/0xb0
[ 2073.019229] __bfq_put_async_bfqq+0xa0/0x168
[ 2073.019233] bfq_put_async_queues+0xbc/0x208
[ 2073.019236] bfq_pd_offline+0x178/0x238
[ 2073.019240] blkcg_deactivate_policy+0x1f0/0x420
[ 2073.019244] bfq_exit_queue+0x128/0x178
[ 2073.019249] blk_mq_exit_sched+0x12c/0x160
[ 2073.019252] elevator_exit+0xc8/0xd0
[ 2073.019256] blk_exit_queue+0x50/0x88
[ 2073.019259] blk_cleanup_queue+0x228/0x3d8
[ 2073.019267] null_del_dev+0xfc/0x1e0 [null_blk]
[ 2073.019274] null_exit+0x90/0x114 [null_blk]
[ 2073.019278] __arm64_sys_delete_module+0x358/0x5a0
[ 2073.019282] el0_svc_common+0xc8/0x320
[ 2073.019287] el0_svc_handler+0xf8/0x160
[ 2073.019290] el0_svc+0x10/0x218
[ 2073.019291]
[ 2073.019294] Allocated by task 14163:
[ 2073.019301] kasan_kmalloc+0xe0/0x190
[ 2073.019305] kmem_cache_alloc_node_trace+0x1cc/0x418
[ 2073.019308] bfq_pd_alloc+0x54/0x118
[ 2073.019313] blkcg_activate_policy+0x250/0x460
[ 2073.019317] bfq_create_group_hierarchy+0x38/0x110
[ 2073.019321] bfq_init_queue+0x6d0/0x948
[ 2073.019325] blk_mq_init_sched+0x1d8/0x390
[ 2073.019330] elevator_switch_mq+0x88/0x170
[ 2073.019334] elevator_switch+0x140/0x270
[ 2073.019338] elv_iosched_store+0x1a4/0x2a0
[ 2073.019342] queue_attr_store+0x90/0xe0
[ 2073.019348] sysfs_kf_write+0xa8/0xe8
[ 2073.019351] kernfs_fop_write+0x1f8/0x378
[ 2073.019359] __vfs_write+0xe0/0x360
[ 2073.019363] vfs_write+0xf0/0x270
[ 2073.019367] ksys_write+0xdc/0x1b8
[ 2073.019371] __arm64_sys_write+0x50/0x60
[ 2073.019375] el0_svc_common+0xc8/0x320
[ 2073.019380] el0_svc_handler+0xf8/0x160
[ 2073.019383] el0_svc+0x10/0x218
[ 2073.019385]
[ 2073.019387] Freed by task 72584:
[ 2073.019391] __kasan_slab_free+0x120/0x228
[ 2073.019394] kasan_slab_free+0x10/0x18
[ 2073.019397] kfree+0x94/0x368
[ 2073.019400] bfqg_put+0x64/0xb0
[ 2073.019404] bfqg_and_blkg_put+0x90/0xb0
[ 2073.019408] bfq_put_queue+0x220/0x228
[ 2073.019413] __bfq_put_async_bfqq+0x98/0x168
[ 2073.019416] bfq_put_async_queues+0xbc/0x208
[ 2073.019420] bfq_pd_offline+0x178/0x238
[ 2073.019424] blkcg_deactivate_policy+0x1f0/0x420
[ 2073.019429] bfq_exit_queue+0x128/0x178
[ 2073.019433] blk_mq_exit_sched+0x12c/0x160
[ 2073.019437] elevator_exit+0xc8/0xd0
[ 2073.019440] blk_exit_queue+0x50/0x88
[ 2073.019443] blk_cleanup_queue+0x228/0x3d8
[ 2073.019451] null_del_dev+0xfc/0x1e0 [null_blk]
[ 2073.019459] null_exit+0x90/0x114 [null_blk]
[ 2073.019462] __arm64_sys_delete_module+0x358/0x5a0
[ 2073.019467] el0_svc_common+0xc8/0x320
[ 2073.019471] el0_svc_handler+0xf8/0x160
[ 2073.019474] el0_svc+0x10/0x218
[ 2073.019475]
[ 2073.019479] The buggy address belongs to the object at ffff8000ccf63f00
which belongs to the cache kmalloc-1024 of size 1024
[ 2073.019484] The buggy address is located 552 bytes inside of
1024-byte region [ffff8000ccf63f00, ffff8000ccf64300)
[ 2073.019486] The buggy address belongs to the page:
[ 2073.019492] page:ffff7e000333d800 count:1 mapcount:0 mapping:ffff8000c0003a00 index:0x0 compound_mapcount: 0
[ 2073.020123] flags: 0x7ffff0000008100(slab|head)
[ 2073.020403] raw: 07ffff0000008100 ffff7e0003334c08 ffff7e00001f5a08 ffff8000c0003a00
[ 2073.020409] ra
---truncated---
CVSS Score
7.8
EPSS Score
0.001
Published
2025-02-26