CVE-2024-46828

Source
https://nvd.nist.gov/vuln/detail/CVE-2024-46828
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2024-46828.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2024-46828
Downstream
Related
Published
2024-09-27T12:39:27Z
Modified
2025-10-17T14:23:57.564184Z
Summary
sched: sch_cake: fix bulk flow accounting logic for host fairness
Details

In the Linux kernel, the following vulnerability has been resolved:

sched: sch_cake: fix bulk flow accounting logic for host fairness

In sch_cake, we keep track of the count of active bulk flows per host, when running in dst/src host fairness mode, which is used as the round-robin weight when iterating through flows. The count of active bulk flows is updated whenever a flow changes state.

This has a peculiar interaction with the hash collision handling: when a hash collision occurs (after the set-associative hashing), the state of the hash bucket is simply updated to match the new packet that collided, and if host fairness is enabled, that also means assigning new per-host state to the flow. For this reason, the bulk flow counters of the host(s) assigned to the flow are decremented, before new state is assigned (and the counters, which may not belong to the same host anymore, are incremented again).

Back when this code was introduced, the host fairness mode was always enabled, so the decrement was unconditional. When the configuration flags were introduced the increment was made conditional, but the decrement was not. Which of course can lead to a spurious decrement (and associated wrap-around to U16_MAX).

AFAICT, when host fairness is disabled, the decrement and wrap-around happens as soon as a hash collision occurs (which is not that common in itself, due to the set-associative hashing). However, in most cases this is harmless, as the value is only used when host fairness mode is enabled. So in order to trigger an array overflow, sch_cake has to first be configured with host fairness disabled, and while running in this mode, a hash collision has to occur to cause the overflow. Then, the qdisc has to be reconfigured to enable host fairness, which leads to the array out-of-bounds because the wrapped-around value is retained and used as an array index. It seems that syzbot managed to trigger this, which is quite impressive in its own right.

This patch fixes the issue by introducing the same conditional check on decrement as is used on increment.

The original bug predates the upstreaming of cake, but the commit listed in the Fixes tag touched that code, meaning that this patch won't apply before that.

References

Affected packages

Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Affected ranges

Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
712639929912c5eefb09facccb48d55b3f72c9f8
Fixed
4a4eeefa514db570be025ab46d779af180e2c9bb
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
712639929912c5eefb09facccb48d55b3f72c9f8
Fixed
7725152b54d295b7da5e34c2f419539b30d017bd
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
712639929912c5eefb09facccb48d55b3f72c9f8
Fixed
cde71a5677971f4f1b69b25e854891dbe78066a4
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
712639929912c5eefb09facccb48d55b3f72c9f8
Fixed
549e407569e08459d16122341d332cb508024094
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
712639929912c5eefb09facccb48d55b3f72c9f8
Fixed
d4a9039a7b3d8005b90c7b1a55a306444f0e5447
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
712639929912c5eefb09facccb48d55b3f72c9f8
Fixed
d7c01c0714c04431b5e18cf17a9ea68a553d1c3c
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
712639929912c5eefb09facccb48d55b3f72c9f8
Fixed
546ea84d07e3e324644025e2aae2d12ea4c5896e

Affected versions

v5.*

v5.0
v5.0-rc8
v5.1
v5.1-rc1
v5.1-rc2
v5.1-rc3
v5.1-rc4
v5.1-rc5
v5.1-rc6
v5.1-rc7
v5.10
v5.10-rc1
v5.10-rc2
v5.10-rc3
v5.10-rc4
v5.10-rc5
v5.10-rc6
v5.10-rc7
v5.10.1
v5.10.10
v5.10.100
v5.10.101
v5.10.102
v5.10.103
v5.10.104
v5.10.105
v5.10.106
v5.10.107
v5.10.108
v5.10.109
v5.10.11
v5.10.110
v5.10.111
v5.10.112
v5.10.113
v5.10.114
v5.10.115
v5.10.116
v5.10.117
v5.10.118
v5.10.119
v5.10.12
v5.10.120
v5.10.121
v5.10.122
v5.10.123
v5.10.124
v5.10.125
v5.10.126
v5.10.127
v5.10.128
v5.10.129
v5.10.13
v5.10.130
v5.10.131
v5.10.132
v5.10.133
v5.10.134
v5.10.135
v5.10.136
v5.10.137
v5.10.138
v5.10.139
v5.10.14
v5.10.140
v5.10.141
v5.10.142
v5.10.143
v5.10.144
v5.10.145
v5.10.146
v5.10.147
v5.10.148
v5.10.149
v5.10.15
v5.10.150
v5.10.151
v5.10.152
v5.10.153
v5.10.154
v5.10.155
v5.10.156
v5.10.157
v5.10.158
v5.10.159
v5.10.16
v5.10.160
v5.10.161
v5.10.162
v5.10.163
v5.10.164
v5.10.165
v5.10.166
v5.10.167
v5.10.168
v5.10.169
v5.10.17
v5.10.170
v5.10.171
v5.10.172
v5.10.173
v5.10.174
v5.10.175
v5.10.176
v5.10.177
v5.10.178
v5.10.179
v5.10.18
v5.10.180
v5.10.181
v5.10.182
v5.10.183
v5.10.184
v5.10.185
v5.10.186
v5.10.187
v5.10.188
v5.10.189
v5.10.19
v5.10.190
v5.10.191
v5.10.192
v5.10.193
v5.10.194
v5.10.195
v5.10.196
v5.10.197
v5.10.198
v5.10.199
v5.10.2
v5.10.20
v5.10.200
v5.10.201
v5.10.202
v5.10.203
v5.10.204
v5.10.205
v5.10.206
v5.10.207
v5.10.208
v5.10.209
v5.10.21
v5.10.210
v5.10.211
v5.10.212
v5.10.213
v5.10.214
v5.10.215
v5.10.216
v5.10.217
v5.10.218
v5.10.219
v5.10.22
v5.10.220
v5.10.221
v5.10.222
v5.10.223
v5.10.224
v5.10.225
v5.10.23
v5.10.24
v5.10.25
v5.10.26
v5.10.27
v5.10.28
v5.10.29
v5.10.3
v5.10.30
v5.10.31
v5.10.32
v5.10.33
v5.10.34
v5.10.35
v5.10.36
v5.10.37
v5.10.38
v5.10.39
v5.10.4
v5.10.40
v5.10.41
v5.10.42
v5.10.43
v5.10.44
v5.10.45
v5.10.46
v5.10.47
v5.10.48
v5.10.49
v5.10.5
v5.10.50
v5.10.51
v5.10.52
v5.10.53
v5.10.54
v5.10.55
v5.10.56
v5.10.57
v5.10.58
v5.10.59
v5.10.6
v5.10.60
v5.10.61
v5.10.62
v5.10.63
v5.10.64
v5.10.65
v5.10.66
v5.10.67
v5.10.68
v5.10.69
v5.10.7
v5.10.70
v5.10.71
v5.10.72
v5.10.73
v5.10.74
v5.10.75
v5.10.76
v5.10.77
v5.10.78
v5.10.79
v5.10.8
v5.10.80
v5.10.81
v5.10.82
v5.10.83
v5.10.84
v5.10.85
v5.10.86
v5.10.87
v5.10.88
v5.10.89
v5.10.9
v5.10.90
v5.10.91
v5.10.92
v5.10.93
v5.10.94
v5.10.95
v5.10.96
v5.10.97
v5.10.98
v5.10.99
v5.11
v5.11-rc1
v5.11-rc2
v5.11-rc3
v5.11-rc4
v5.11-rc5
v5.11-rc6
v5.11-rc7
v5.12
v5.12-rc1
v5.12-rc1-dontuse
v5.12-rc2
v5.12-rc3
v5.12-rc4
v5.12-rc5
v5.12-rc6
v5.12-rc7
v5.12-rc8
v5.13
v5.13-rc1
v5.13-rc2
v5.13-rc3
v5.13-rc4
v5.13-rc5
v5.13-rc6
v5.13-rc7
v5.14
v5.14-rc1
v5.14-rc2
v5.14-rc3
v5.14-rc4
v5.14-rc5
v5.14-rc6
v5.14-rc7
v5.15
v5.15-rc1
v5.15-rc2
v5.15-rc3
v5.15-rc4
v5.15-rc5
v5.15-rc6
v5.15-rc7
v5.15.1
v5.15.10
v5.15.100
v5.15.101
v5.15.102
v5.15.103
v5.15.104
v5.15.105
v5.15.106
v5.15.107
v5.15.108
v5.15.109
v5.15.11
v5.15.110
v5.15.111
v5.15.112
v5.15.113
v5.15.114
v5.15.115
v5.15.116
v5.15.117
v5.15.118
v5.15.119
v5.15.12
v5.15.120
v5.15.121
v5.15.122
v5.15.123
v5.15.124
v5.15.125
v5.15.126
v5.15.127
v5.15.128
v5.15.129
v5.15.13
v5.15.130
v5.15.131
v5.15.132
v5.15.133
v5.15.134
v5.15.135
v5.15.136
v5.15.137
v5.15.138
v5.15.139
v5.15.14
v5.15.140
v5.15.141
v5.15.142
v5.15.143
v5.15.144
v5.15.145
v5.15.146
v5.15.147
v5.15.148
v5.15.149
v5.15.15
v5.15.150
v5.15.151
v5.15.152
v5.15.153
v5.15.154
v5.15.155
v5.15.156
v5.15.157
v5.15.158
v5.15.159
v5.15.16
v5.15.160
v5.15.161
v5.15.162
v5.15.163
v5.15.164
v5.15.165
v5.15.166
v5.15.17
v5.15.18
v5.15.19
v5.15.2
v5.15.20
v5.15.21
v5.15.22
v5.15.23
v5.15.24
v5.15.25
v5.15.26
v5.15.27
v5.15.28
v5.15.29
v5.15.3
v5.15.30
v5.15.31
v5.15.32
v5.15.33
v5.15.34
v5.15.35
v5.15.36
v5.15.37
v5.15.38
v5.15.39
v5.15.4
v5.15.40
v5.15.41
v5.15.42
v5.15.43
v5.15.44
v5.15.45
v5.15.46
v5.15.47
v5.15.48
v5.15.49
v5.15.5
v5.15.50
v5.15.51
v5.15.52
v5.15.53
v5.15.54
v5.15.55
v5.15.56
v5.15.57
v5.15.58
v5.15.59
v5.15.6
v5.15.60
v5.15.61
v5.15.62
v5.15.63
v5.15.64
v5.15.65
v5.15.66
v5.15.67
v5.15.68
v5.15.69
v5.15.7
v5.15.70
v5.15.71
v5.15.72
v5.15.73
v5.15.74
v5.15.75
v5.15.76
v5.15.77
v5.15.78
v5.15.79
v5.15.8
v5.15.80
v5.15.81
v5.15.82
v5.15.83
v5.15.84
v5.15.85
v5.15.86
v5.15.87
v5.15.88
v5.15.89
v5.15.9
v5.15.90
v5.15.91
v5.15.92
v5.15.93
v5.15.94
v5.15.95
v5.15.96
v5.15.97
v5.15.98
v5.15.99
v5.16
v5.16-rc1
v5.16-rc2
v5.16-rc3
v5.16-rc4
v5.16-rc5
v5.16-rc6
v5.16-rc7
v5.16-rc8
v5.17
v5.17-rc1
v5.17-rc2
v5.17-rc3
v5.17-rc4
v5.17-rc5
v5.17-rc6
v5.17-rc7
v5.17-rc8
v5.18
v5.18-rc1
v5.18-rc2
v5.18-rc3
v5.18-rc4
v5.18-rc5
v5.18-rc6
v5.18-rc7
v5.19
v5.19-rc1
v5.19-rc2
v5.19-rc3
v5.19-rc4
v5.19-rc5
v5.19-rc6
v5.19-rc7
v5.19-rc8
v5.2
v5.2-rc1
v5.2-rc2
v5.2-rc3
v5.2-rc4
v5.2-rc5
v5.2-rc6
v5.2-rc7
v5.3
v5.3-rc1
v5.3-rc2
v5.3-rc3
v5.3-rc4
v5.3-rc5
v5.3-rc6
v5.3-rc7
v5.3-rc8
v5.4
v5.4-rc1
v5.4-rc2
v5.4-rc3
v5.4-rc4
v5.4-rc5
v5.4-rc6
v5.4-rc7
v5.4-rc8
v5.4.1
v5.4.10
v5.4.100
v5.4.101
v5.4.102
v5.4.103
v5.4.104
v5.4.105
v5.4.106
v5.4.107
v5.4.108
v5.4.109
v5.4.11
v5.4.110
v5.4.111
v5.4.112
v5.4.113
v5.4.114
v5.4.115
v5.4.116
v5.4.117
v5.4.118
v5.4.119
v5.4.12
v5.4.120
v5.4.121
v5.4.122
v5.4.123
v5.4.124
v5.4.125
v5.4.126
v5.4.127
v5.4.128
v5.4.129
v5.4.13
v5.4.130
v5.4.131
v5.4.132
v5.4.133
v5.4.134
v5.4.135
v5.4.136
v5.4.137
v5.4.138
v5.4.139
v5.4.14
v5.4.140
v5.4.141
v5.4.142
v5.4.143
v5.4.144
v5.4.145
v5.4.146
v5.4.147
v5.4.148
v5.4.149
v5.4.15
v5.4.150
v5.4.151
v5.4.152
v5.4.153
v5.4.154
v5.4.155
v5.4.156
v5.4.157
v5.4.158
v5.4.159
v5.4.16
v5.4.160
v5.4.161
v5.4.162
v5.4.163
v5.4.164
v5.4.165
v5.4.166
v5.4.167
v5.4.168
v5.4.169
v5.4.17
v5.4.170
v5.4.171
v5.4.172
v5.4.173
v5.4.174
v5.4.175
v5.4.176
v5.4.177
v5.4.178
v5.4.179
v5.4.18
v5.4.180
v5.4.181
v5.4.182
v5.4.183
v5.4.184
v5.4.185
v5.4.186
v5.4.187
v5.4.188
v5.4.189
v5.4.19
v5.4.190
v5.4.191
v5.4.192
v5.4.193
v5.4.194
v5.4.195
v5.4.196
v5.4.197
v5.4.198
v5.4.199
v5.4.2
v5.4.20
v5.4.200
v5.4.201
v5.4.202
v5.4.203
v5.4.204
v5.4.205
v5.4.206
v5.4.207
v5.4.208
v5.4.209
v5.4.21
v5.4.210
v5.4.211
v5.4.212
v5.4.213
v5.4.214
v5.4.215
v5.4.216
v5.4.217
v5.4.218
v5.4.219
v5.4.22
v5.4.220
v5.4.221
v5.4.222
v5.4.223
v5.4.224
v5.4.225
v5.4.226
v5.4.227
v5.4.228
v5.4.229
v5.4.23
v5.4.230
v5.4.231
v5.4.232
v5.4.233
v5.4.234
v5.4.235
v5.4.236
v5.4.237
v5.4.238
v5.4.239
v5.4.24
v5.4.240
v5.4.241
v5.4.242
v5.4.243
v5.4.244
v5.4.245
v5.4.246
v5.4.247
v5.4.248
v5.4.249
v5.4.25
v5.4.250
v5.4.251
v5.4.252
v5.4.253
v5.4.254
v5.4.255
v5.4.256
v5.4.257
v5.4.258
v5.4.259
v5.4.26
v5.4.260
v5.4.261
v5.4.262
v5.4.263
v5.4.264
v5.4.265
v5.4.266
v5.4.267
v5.4.268
v5.4.269
v5.4.27
v5.4.270
v5.4.271
v5.4.272
v5.4.273
v5.4.274
v5.4.275
v5.4.276
v5.4.277
v5.4.278
v5.4.279
v5.4.28
v5.4.280
v5.4.281
v5.4.282
v5.4.283
v5.4.29
v5.4.3
v5.4.30
v5.4.31
v5.4.32
v5.4.33
v5.4.34
v5.4.35
v5.4.36
v5.4.37
v5.4.38
v5.4.39
v5.4.4
v5.4.40
v5.4.41
v5.4.42
v5.4.43
v5.4.44
v5.4.45
v5.4.46
v5.4.47
v5.4.48
v5.4.49
v5.4.5
v5.4.50
v5.4.51
v5.4.52
v5.4.53
v5.4.54
v5.4.55
v5.4.56
v5.4.57
v5.4.58
v5.4.59
v5.4.6
v5.4.60
v5.4.61
v5.4.62
v5.4.63
v5.4.64
v5.4.65
v5.4.66
v5.4.67
v5.4.68
v5.4.69
v5.4.7
v5.4.70
v5.4.71
v5.4.72
v5.4.73
v5.4.74
v5.4.75
v5.4.76
v5.4.77
v5.4.78
v5.4.79
v5.4.8
v5.4.80
v5.4.81
v5.4.82
v5.4.83
v5.4.84
v5.4.85
v5.4.86
v5.4.87
v5.4.88
v5.4.89
v5.4.9
v5.4.90
v5.4.91
v5.4.92
v5.4.93
v5.4.94
v5.4.95
v5.4.96
v5.4.97
v5.4.98
v5.4.99
v5.5
v5.5-rc1
v5.5-rc2
v5.5-rc3
v5.5-rc4
v5.5-rc5
v5.5-rc6
v5.5-rc7
v5.6
v5.6-rc1
v5.6-rc2
v5.6-rc3
v5.6-rc4
v5.6-rc5
v5.6-rc6
v5.6-rc7
v5.7
v5.7-rc1
v5.7-rc2
v5.7-rc3
v5.7-rc4
v5.7-rc5
v5.7-rc6
v5.7-rc7
v5.8
v5.8-rc1
v5.8-rc2
v5.8-rc3
v5.8-rc4
v5.8-rc5
v5.8-rc6
v5.8-rc7
v5.9
v5.9-rc1
v5.9-rc2
v5.9-rc3
v5.9-rc4
v5.9-rc5
v5.9-rc6
v5.9-rc7
v5.9-rc8

v6.*

v6.0
v6.0-rc1
v6.0-rc2
v6.0-rc3
v6.0-rc4
v6.0-rc5
v6.0-rc6
v6.0-rc7
v6.1
v6.1-rc1
v6.1-rc2
v6.1-rc3
v6.1-rc4
v6.1-rc5
v6.1-rc6
v6.1-rc7
v6.1-rc8
v6.1.1
v6.1.10
v6.1.100
v6.1.101
v6.1.102
v6.1.103
v6.1.104
v6.1.105
v6.1.106
v6.1.107
v6.1.108
v6.1.109
v6.1.11
v6.1.12
v6.1.13
v6.1.14
v6.1.15
v6.1.16
v6.1.17
v6.1.18
v6.1.19
v6.1.2
v6.1.20
v6.1.21
v6.1.22
v6.1.23
v6.1.24
v6.1.25
v6.1.26
v6.1.27
v6.1.28
v6.1.29
v6.1.3
v6.1.30
v6.1.31
v6.1.32
v6.1.33
v6.1.34
v6.1.35
v6.1.36
v6.1.37
v6.1.38
v6.1.39
v6.1.4
v6.1.40
v6.1.41
v6.1.42
v6.1.43
v6.1.44
v6.1.45
v6.1.46
v6.1.47
v6.1.48
v6.1.49
v6.1.5
v6.1.50
v6.1.51
v6.1.52
v6.1.53
v6.1.54
v6.1.55
v6.1.56
v6.1.57
v6.1.58
v6.1.59
v6.1.6
v6.1.60
v6.1.61
v6.1.62
v6.1.63
v6.1.64
v6.1.65
v6.1.66
v6.1.67
v6.1.68
v6.1.69
v6.1.7
v6.1.70
v6.1.71
v6.1.72
v6.1.73
v6.1.74
v6.1.75
v6.1.76
v6.1.77
v6.1.78
v6.1.79
v6.1.8
v6.1.80
v6.1.81
v6.1.82
v6.1.83
v6.1.84
v6.1.85
v6.1.86
v6.1.87
v6.1.88
v6.1.89
v6.1.9
v6.1.90
v6.1.91
v6.1.92
v6.1.93
v6.1.94
v6.1.95
v6.1.96
v6.1.97
v6.1.98
v6.1.99
v6.10
v6.10-rc1
v6.10-rc2
v6.10-rc3
v6.10-rc4
v6.10-rc5
v6.10-rc6
v6.10-rc7
v6.10.1
v6.10.2
v6.10.3
v6.10.4
v6.10.5
v6.10.6
v6.10.7
v6.10.8
v6.10.9
v6.11-rc1
v6.11-rc2
v6.11-rc3
v6.11-rc4
v6.11-rc5
v6.2
v6.2-rc1
v6.2-rc2
v6.2-rc3
v6.2-rc4
v6.2-rc5
v6.2-rc6
v6.2-rc7
v6.2-rc8
v6.3
v6.3-rc1
v6.3-rc2
v6.3-rc3
v6.3-rc4
v6.3-rc5
v6.3-rc6
v6.3-rc7
v6.4
v6.4-rc1
v6.4-rc2
v6.4-rc3
v6.4-rc4
v6.4-rc5
v6.4-rc6
v6.4-rc7
v6.5
v6.5-rc1
v6.5-rc2
v6.5-rc3
v6.5-rc4
v6.5-rc5
v6.5-rc6
v6.5-rc7
v6.6
v6.6-rc1
v6.6-rc2
v6.6-rc3
v6.6-rc4
v6.6-rc5
v6.6-rc6
v6.6-rc7
v6.6.1
v6.6.10
v6.6.11
v6.6.12
v6.6.13
v6.6.14
v6.6.15
v6.6.16
v6.6.17
v6.6.18
v6.6.19
v6.6.2
v6.6.20
v6.6.21
v6.6.22
v6.6.23
v6.6.24
v6.6.25
v6.6.26
v6.6.27
v6.6.28
v6.6.29
v6.6.3
v6.6.30
v6.6.31
v6.6.32
v6.6.33
v6.6.34
v6.6.35
v6.6.36
v6.6.37
v6.6.38
v6.6.39
v6.6.4
v6.6.40
v6.6.41
v6.6.42
v6.6.43
v6.6.44
v6.6.45
v6.6.46
v6.6.47
v6.6.48
v6.6.49
v6.6.5
v6.6.50
v6.6.6
v6.6.7
v6.6.8
v6.6.9
v6.7
v6.7-rc1
v6.7-rc2
v6.7-rc3
v6.7-rc4
v6.7-rc5
v6.7-rc6
v6.7-rc7
v6.7-rc8
v6.8
v6.8-rc1
v6.8-rc2
v6.8-rc3
v6.8-rc4
v6.8-rc5
v6.8-rc6
v6.8-rc7
v6.9
v6.9-rc1
v6.9-rc2
v6.9-rc3
v6.9-rc4
v6.9-rc5
v6.9-rc6
v6.9-rc7

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
5.1.0
Fixed
5.4.284
Type
ECOSYSTEM
Events
Introduced
5.5.0
Fixed
5.10.226
Type
ECOSYSTEM
Events
Introduced
5.11.0
Fixed
5.15.167
Type
ECOSYSTEM
Events
Introduced
5.16.0
Fixed
6.1.110
Type
ECOSYSTEM
Events
Introduced
6.2.0
Fixed
6.6.51
Type
ECOSYSTEM
Events
Introduced
6.7.0
Fixed
6.10.10