CVE-2021-47363
published 2024-05-21CVE-2021-47363: In the Linux kernel, the following vulnerability has been resolved: nexthop: Fix division by zero while replacing a resilient group The resilient nexthop group…
PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.21%
11.0th percentile
In the Linux kernel, the following vulnerability has been resolved:
nexthop: Fix division by zero while replacing a resilient group
The resilient nexthop group torture tests in fib_nexthop.sh exposed a
possible division by zero while replacing a resilient group [1]. The
division by zero occurs when the data path sees a resilient nexthop
group with zero buckets.
The tests replace a resilient nexthop group in a loop while traffic is
forwarded through it. The tests do not specify the number of buckets
while performing the replacement, resulting in the kernel allocating a
stub resilient table (i.e, 'struct nh_res_table') with zero buckets.
This table should never be visible to the data path, but the old nexthop
group (i.e., 'oldg') might still be used by the data path when the stub
table is assigned to it.
Fix this by only assigning the stub table to the old nexthop group after
making sure the group is no longer used by the data path.
Tested with fib_nexthops.sh:
Tests passed: 222
Tests failed: 0
[1]
divide error: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 1850 Comm: ping Not tainted 5.14.0-custom-10271-ga86eb53057fe #1107
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-4.fc34 04/01/2014
RIP: 0010:nexthop_select_path+0x2d2/0x1a80
[...]
Call Trace:
fib_select_multipath+0x79b/0x1530
fib_select_path+0x8fb/0x1c10
ip_route_output_key_hash_rcu+0x1198/0x2da0
ip_route_output_key_hash+0x190/0x340
ip_route_output_flow+0x21/0x120
raw_sendmsg+0x91d/0x2e10
inet_sendmsg+0x9e/0xe0
__sys_sendto+0x23d/0x360
__x64_sys_sendto+0xe1/0x1b0
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae
Affected
9 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.14.9-1 (bookworm) | linux 5.14.9-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 283a72a5599e80750699d2021830a294ed9ab3f3 < e9d32ec26e7f01d1af13bdc687f586362546aa25 | e9d32ec26e7f01d1af13bdc687f586362546aa25 |
| linux | linux | >= 283a72a5599e80750699d2021830a294ed9ab3f3 < 563f23b002534176f49524b5ca0e1d94d8906c40 | 563f23b002534176f49524b5ca0e1d94d8906c40 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.14.9-1 | 5.14.9-1 |
| linux | linux_kernel | >= 0 < 5.14.9-1 | 5.14.9-1 |
| linux | linux_kernel | >= 0 < 5.14.9-1 | 5.14.9-1 |
| linux | linux_kernel | >= 5.13 < 5.14.9 | 5.14.9 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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OSV
CVE-2021-47363: In the Linux kernel, the following vulnerability has been resolved: nexthop: Fix division by zero while replacing a resilient group The resilient next
osv·2024-05-21·CVSS 5.5
CVE-2021-47363 [MEDIUM] CVE-2021-47363: In the Linux kernel, the following vulnerability has been resolved: nexthop: Fix division by zero while replacing a resilient group The resilient next
In the Linux kernel, the following vulnerability has been resolved: nexthop: Fix division by zero while replacing a resilient group The resilient nexthop group torture tests in fib_nexthop.sh exposed a possible division by zero while replacing a resilient group [1]. The division by zero occurs when the data path sees a resilient nexthop group with zero buckets. The tests replace a resilient nexthop group in a loop while traffic is forwarded through it. The tests do not specify the number of buckets while performing the replacement, resulting in the kernel allocating a stub resilient table (i.e, 'struct nh_res_table') with zero buckets. This table should never be visible to the data path, but the old nexthop group (i.e., 'oldg') might still be used by the data path when the stub table is as
GHSA
GHSA-5w2f-hr95-2h6j: In the Linux kernel, the following vulnerability has been resolved:
nexthop: Fix division by zero while replacing a resilient group
The resilient ne
ghsa_unreviewed·2024-05-21
CVE-2021-47363 [MEDIUM] CWE-369 GHSA-5w2f-hr95-2h6j: In the Linux kernel, the following vulnerability has been resolved:
nexthop: Fix division by zero while replacing a resilient group
The resilient ne
In the Linux kernel, the following vulnerability has been resolved:
nexthop: Fix division by zero while replacing a resilient group
The resilient nexthop group torture tests in fib_nexthop.sh exposed a
possible division by zero while replacing a resilient group [1]. The
division by zero occurs when the data path sees a resilient nexthop
group with zero buckets.
The tests replace a resilient nexthop group in a loop while traffic is
forwarded through it. The tests do not specify the number of buckets
while performing the replacement, resulting in the kernel allocating a
stub resilient table (i.e, 'struct nh_res_table') with zero buckets.
This table should never be visible to the data path, but the old nexthop
group (i.e., 'oldg') might still be used by the data path when the stub
table i
Red Hat
kernel: nexthop: Fix division by zero while replacing a resilient group
vendor_redhat·2024-05-21·CVSS 5.5
CVE-2021-47363 [MEDIUM] CWE-369 kernel: nexthop: Fix division by zero while replacing a resilient group
kernel: nexthop: Fix division by zero while replacing a resilient group
In the Linux kernel, the following vulnerability has been resolved:
nexthop: Fix division by zero while replacing a resilient group
The resilient nexthop group torture tests in fib_nexthop.sh exposed a
possible division by zero while replacing a resilient group [1]. The
division by zero occurs when the data path sees a resilient nexthop
group with zero buckets.
The tests replace a resilient nexthop group in a loop while traffic is
forwarded through it. The tests do not specify the number of buckets
while performing the replacement, resulting in the kernel allocating a
stub resilient table (i.e, 'struct nh_res_table') with zero buckets.
This table should never be visible to the data path, but the old nexthop
group (i.e
Debian
CVE-2021-47363: linux - In the Linux kernel, the following vulnerability has been resolved: nexthop: Fi...
vendor_debian·2021·CVSS 5.5
CVE-2021-47363 [MEDIUM] CVE-2021-47363: linux - In the Linux kernel, the following vulnerability has been resolved: nexthop: Fi...
In the Linux kernel, the following vulnerability has been resolved: nexthop: Fix division by zero while replacing a resilient group The resilient nexthop group torture tests in fib_nexthop.sh exposed a possible division by zero while replacing a resilient group [1]. The division by zero occurs when the data path sees a resilient nexthop group with zero buckets. The tests replace a resilient nexthop group in a loop while traffic is forwarded through it. The tests do not specify the number of buckets while performing the replacement, resulting in the kernel allocating a stub resilient table (i.e, 'struct nh_res_table') with zero buckets. This table should never be visible to the data path, but the old nexthop group (i.e., 'oldg') might still be used by the data path when the stub table is as
No detection rules found.
No public exploits indexed.
2024-05-21
Published