CVE-2026-74261

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Source
https://cve.org/CVERecord?id=CVE-2026-74261
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74261.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-74261
Downstream
BELL (1)
DEBIAN (1)
openSUSE (1)
SUSE (5)
UBUNTU (1)
Related
openSUSE (1)
SUSE (5)
Published
2026-08-15T05:57:38Z
Modified
2026-10-08T02:51:54Z
Summary
ALSA: seq: avoid stale FIFO cells during resize
Details

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

ALSA: seq: avoid stale FIFO cells during resize

snd_seq_fifo_resize() still needs to publish the replacement pool before it waits for FIFO users. A blocking snd_seq_read() holds f->use_lock while it sleeps, so concurrent senders must be able to queue to the new pool and wake that reader instead of failing against a closing old pool.

However, snd_seq_fifo_event_in() duplicates an event before it takes f->lock, and snd_seq_read() can dequeue a cell and later call snd_seq_fifo_cell_putback() if copy_to_user() or snd_seq_expand_var_event() fails. If resize swaps f->pool and detaches oldhead in between, either path can relink an old-pool cell after the snapshot. That stale cell sits outside the drained oldhead list, keeps oldpool->counter elevated, and can leave snd_seq_pool_delete() waiting for the retired pool to drain.

Keep the existing swap-before-wait ordering in snd_seq_fifo_resize(), but reject stale cells before any FIFO relink. Revalidate event-in cells under f->lock and retry them against the published replacement pool, and free stale putback cells instead of linking them back into the FIFO.

The buggy scenario involves two paths, with each column showing the order within that path:

resize path: relink path:

  1. Allocate newpool. 1. Take f->use_lock.
  2. Swap f->pool to newpool and 2. Duplicate or dequeue an old-pool detach oldhead. cell before oldpool closes.
  3. Mark oldpool closing and 3. Reach a later relink point after wait for FIFO users. resize published newpool.
  4. Free oldhead and delete 4. Relink the old-pool cell after oldpool. resize detached oldhead. 5. Drop f->use_lock.

The reproducer reports a resize ioctl blocked in the expected pool teardown path:

signal: resize iteration=98 target_pool=4 exceeded 250ms (elapsed=251ms) diagnostic: resize_tid=651 wchan=snd_seq_pool_done diagnostic: resize_tid=651 stack= snd_seq_pool_done+0x5b/0x140 snd_seq_pool_delete+0x7a/0x90 snd_seq_fifo_resize+0x193/0x1e0 snd_seq_ioctl_set_client_pool+0x214/0x260 snd_seq_ioctl+0x119/0x540 __x64_sys_ioctl+0xd1/0x120 do_syscall_64+0xbb/0x2f0 entry_SYSCALL_64_after_hwframe+0x77/0x7f

A second run with larger pools hit the same target path:

signal: resize iteration=32 target_pool=64 exceeded 250ms (elapsed=251ms) diagnostic: resize_tid=663 wchan=snd_seq_pool_done diagnostic: resize_tid=663 stack= snd_seq_pool_done+0x5b/0x140 snd_seq_pool_delete+0x7a/0x90 snd_seq_fifo_resize+0x193/0x1e0 snd_seq_ioctl_set_client_pool+0x214/0x260 snd_seq_ioctl+0x119/0x540 __x64_sys_ioctl+0xd1/0x120 do_syscall_64+0xbb/0x2f0 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Database specific 
{
    "cna_assigner":  "Linux",
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74261.json"
}
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
2d7d54002e396c180db0c800c1046f0a3c471597
Fixed
98a965cb1e767b54b6bbd831b6cea26f521a8f51
Fixed
1c4c35fb68d520241f7d9f1c356b5e2370fd8364
Fixed
e546128291f8d688dcb931827e2efd2aa6c0734d
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.2.91
Fixed
3.3
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.10.107
Fixed
3.11
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.12.73
Fixed
3.13
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.16.46
Fixed
3.17
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3.18.50
Fixed
3.19
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
4.1.40
Fixed
4.2
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
4.4.60
Fixed
4.5
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
4.9.21
Fixed
4.10
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
4.10.9
Fixed
4.11
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
df7a2d0af9f7ab73cf22a7b62bbc0bad93a02110
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
28e0ebdd57cd3287ac821068364b74c70af3861c
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
d4b8e8a32d74052fe292618ae19f794944ddc673
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
e91325f27c4d98d1088e9e86b3ab475f752eeb80
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
9ebfed203c0d93449a074c5c2fd5bb3e58518f0d
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3492352e1f34673708fa7409b4b1d97545aa2f1c
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
a90d7447e4a154ad26e3b9e09a0878680be49339
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
74a2c1ff88a4e0960623d17f7db56ac5a60bb0cf
Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
c36ef6467420f8982e6d4d6f93d0634a85a5ee45

Affected versions

v3.*
v3.10.107
v3.10.108
v3.12.73
v3.12.74
v3.16.46
v3.16.47
v3.16.48
v3.16.49
v3.16.50
v3.16.51
v3.16.52
v3.16.53
v3.16.54
v3.16.55
v3.16.56
v3.16.57
v3.16.58
v3.16.59
v3.16.60
v3.16.61
v3.16.62
v3.16.63
v3.16.64
v3.16.65
v3.16.66
v3.16.67
v3.16.68
v3.16.69
v3.16.70
v3.16.71
v3.16.72
v3.16.73
v3.16.74
v3.16.75
v3.16.76
v3.16.77
v3.16.78
v3.16.79
v3.16.80
v3.16.81
v3.16.82
v3.16.83
v3.16.84
v3.16.85
v3.18.100
v3.18.101
v3.18.102
v3.18.103
v3.18.104
v3.18.105
v3.18.106
v3.18.107
v3.18.108
v3.18.109
v3.18.110
v3.18.111
v3.18.112
v3.18.113
v3.18.114
v3.18.115
v3.18.116
v3.18.117
v3.18.118
v3.18.119
v3.18.120
v3.18.121
v3.18.122
v3.18.123
v3.18.124
v3.18.125
v3.18.126
v3.18.127
v3.18.128
v3.18.129
v3.18.130
v3.18.131
v3.18.132
v3.18.133
v3.18.134
v3.18.135
v3.18.136
v3.18.137
v3.18.138
v3.18.139
v3.18.140
v3.18.50
v3.18.51
v3.18.52
v3.18.53
v3.18.54
v3.18.55
v3.18.56
v3.18.57
v3.18.58
v3.18.59
v3.18.60
v3.18.61
v3.18.62
v3.18.63
v3.18.64
v3.18.65
v3.18.66
v3.18.67
v3.18.68
v3.18.69
v3.18.70
v3.18.71
v3.18.72
v3.18.73
v3.18.74
v3.18.75
v3.18.76
v3.18.77
v3.18.78
v3.18.79
v3.18.80
v3.18.81
v3.18.82
v3.18.83
v3.18.84
v3.18.85
v3.18.86
v3.18.87
v3.18.88
v3.18.89
v3.18.90
v3.18.91
v3.18.92
v3.18.93
v3.18.94
v3.18.95
v3.18.96
v3.18.97
v3.18.98
v3.18.99
v3.2.100
v3.2.101
v3.2.102
v3.2.91
v3.2.92
v3.2.93
v3.2.94
v3.2.95
v3.2.96
v3.2.97
v3.2.98
v3.2.99
v4.*
v4.1.40
v4.1.41
v4.1.42
v4.1.43
v4.1.44
v4.1.45
v4.1.46
v4.1.47
v4.1.48
v4.1.49
v4.1.50
v4.1.51
v4.1.52
v4.10.10
v4.10.11
v4.10.12
v4.10.13
v4.10.14
v4.10.15
v4.10.16
v4.10.17
v4.10.9
v4.4.100
v4.4.101
v4.4.102
v4.4.103
v4.4.104
v4.4.105
v4.4.106
v4.4.107
v4.4.108
v4.4.109
v4.4.110
v4.4.111
v4.4.112
v4.4.113
v4.4.114
v4.4.115
v4.4.116
v4.4.117
v4.4.118
v4.4.119
v4.4.120
v4.4.121
v4.4.122
v4.4.123
v4.4.124
v4.4.125
v4.4.126
v4.4.127
v4.4.128
v4.4.129
v4.4.130
v4.4.131
v4.4.132
v4.4.133
v4.4.134
v4.4.135
v4.4.136
v4.4.137
v4.4.138
v4.4.139
v4.4.140
v4.4.141
v4.4.142
v4.4.143
v4.4.144
v4.4.145
v4.4.146
v4.4.147
v4.4.148
v4.4.149
v4.4.150
v4.4.151
v4.4.152
v4.4.153
v4.4.154
v4.4.155
v4.4.156
v4.4.157
v4.4.158
v4.4.159
v4.4.160
v4.4.161
v4.4.162
v4.4.163
v4.4.164
v4.4.165
v4.4.166
v4.4.167
v4.4.168
v4.4.169
v4.4.170
v4.4.171
v4.4.172
v4.4.173
v4.4.174
v4.4.175
v4.4.176
v4.4.177
v4.4.178
v4.4.179
v4.4.180
v4.4.181
v4.4.182
v4.4.183
v4.4.184
v4.4.185
v4.4.186
v4.4.187
v4.4.188
v4.4.189
v4.4.190
v4.4.191
v4.4.192
v4.4.193
v4.4.194
v4.4.195
v4.4.196
v4.4.197
v4.4.198
v4.4.199
v4.4.200
v4.4.201
v4.4.202
v4.4.203
v4.4.204
v4.4.205
v4.4.206
v4.4.207
v4.4.208
v4.4.209
v4.4.210
v4.4.211
v4.4.212
v4.4.213
v4.4.214
v4.4.215
v4.4.216
v4.4.217
v4.4.218
v4.4.219
v4.4.220
v4.4.221
v4.4.222
v4.4.223
v4.4.224
v4.4.225
v4.4.226
v4.4.227
v4.4.228
v4.4.229
v4.4.230
v4.4.231
v4.4.232
v4.4.233
v4.4.234
v4.4.235
v4.4.236
v4.4.237
v4.4.238
v4.4.239
v4.4.240
v4.4.241
v4.4.242
v4.4.243
v4.4.244
v4.4.245
v4.4.246
v4.4.247
v4.4.248
v4.4.249
v4.4.250
v4.4.251
v4.4.252
v4.4.253
v4.4.254
v4.4.255
v4.4.256
v4.4.257
v4.4.258
v4.4.259
v4.4.260
v4.4.261
v4.4.262
v4.4.263
v4.4.264
v4.4.265
v4.4.266
v4.4.267
v4.4.268
v4.4.269
v4.4.270
v4.4.271
v4.4.272
v4.4.273
v4.4.274
v4.4.275
v4.4.276
v4.4.277
v4.4.278
v4.4.279
v4.4.280
v4.4.281
v4.4.282
v4.4.283
v4.4.284
v4.4.285
v4.4.286
v4.4.287
v4.4.288
v4.4.289
v4.4.290
v4.4.291
v4.4.292
v4.4.293
v4.4.294
v4.4.295
v4.4.296
v4.4.297
v4.4.298
v4.4.299
v4.4.300
v4.4.301
v4.4.302
v4.4.60
v4.4.61
v4.4.62
v4.4.63
v4.4.64
v4.4.65
v4.4.66
v4.4.67
v4.4.68
v4.4.69
v4.4.70
v4.4.71
v4.4.72
v4.4.73
v4.4.74
v4.4.75
v4.4.76
v4.4.77
v4.4.78
v4.4.79
v4.4.80
v4.4.81
v4.4.82
v4.4.83
v4.4.84
v4.4.85
v4.4.86
v4.4.87
v4.4.88
v4.4.89
v4.4.90
v4.4.91
v4.4.92
v4.4.93
v4.4.94
v4.4.95
v4.4.96
v4.4.97
v4.4.98
v4.4.99
v4.9.100
v4.9.101
v4.9.102
v4.9.103
v4.9.104
v4.9.105
v4.9.106
v4.9.107
v4.9.108
v4.9.109
v4.9.110
v4.9.111
v4.9.112
v4.9.113
v4.9.114
v4.9.115
v4.9.116
v4.9.117
v4.9.118
v4.9.119
v4.9.120
v4.9.121
v4.9.122
v4.9.123
v4.9.124
v4.9.125
v4.9.126
v4.9.127
v4.9.128
v4.9.129
v4.9.130
v4.9.131
v4.9.132
v4.9.133
v4.9.134
v4.9.135
v4.9.136
v4.9.137
v4.9.138
v4.9.139
v4.9.140
v4.9.141
v4.9.142
v4.9.143
v4.9.144
v4.9.145
v4.9.146
v4.9.147
v4.9.148
v4.9.149
v4.9.150
v4.9.151
v4.9.152
v4.9.153
v4.9.154
v4.9.155
v4.9.156
v4.9.157
v4.9.158
v4.9.159
v4.9.160
v4.9.161
v4.9.162
v4.9.163
v4.9.164
v4.9.165
v4.9.166
v4.9.167
v4.9.168
v4.9.169
v4.9.170
v4.9.171
v4.9.172
v4.9.173
v4.9.174
v4.9.175
v4.9.176
v4.9.177
v4.9.178
v4.9.179
v4.9.180
v4.9.181
v4.9.182
v4.9.183
v4.9.184
v4.9.185
v4.9.186
v4.9.187
v4.9.188
v4.9.189
v4.9.190
v4.9.191
v4.9.192
v4.9.193
v4.9.194
v4.9.195
v4.9.196
v4.9.197
v4.9.198
v4.9.199
v4.9.200
v4.9.201
v4.9.202
v4.9.203
v4.9.204
v4.9.205
v4.9.206
v4.9.207
v4.9.208
v4.9.209
v4.9.21
v4.9.210
v4.9.211
v4.9.212
v4.9.213
v4.9.214
v4.9.215
v4.9.216
v4.9.217
v4.9.218
v4.9.219
v4.9.22
v4.9.220
v4.9.221
v4.9.222
v4.9.223
v4.9.224
v4.9.225
v4.9.226
v4.9.227
v4.9.228
v4.9.229
v4.9.23
v4.9.230
v4.9.231
v4.9.232
v4.9.233
v4.9.234
v4.9.235
v4.9.236
v4.9.237
v4.9.238
v4.9.239
v4.9.24
v4.9.240
v4.9.241
v4.9.242
v4.9.243
v4.9.244
v4.9.245
v4.9.246
v4.9.247
v4.9.248
v4.9.249
v4.9.25
v4.9.250
v4.9.251
v4.9.252
v4.9.253
v4.9.254
v4.9.255
v4.9.256
v4.9.257
v4.9.258
v4.9.259
v4.9.26
v4.9.260
v4.9.261
v4.9.262
v4.9.263
v4.9.264
v4.9.265
v4.9.266
v4.9.267
v4.9.268
v4.9.269
v4.9.27
v4.9.270
v4.9.271
v4.9.272
v4.9.273
v4.9.274
v4.9.275
v4.9.276
v4.9.277
v4.9.278
v4.9.279
v4.9.28
v4.9.280
v4.9.281
v4.9.282
v4.9.283
v4.9.284
v4.9.285
v4.9.286
v4.9.287
v4.9.288
v4.9.289
v4.9.29
v4.9.290
v4.9.291
v4.9.292
v4.9.293
v4.9.294
v4.9.295
v4.9.296
v4.9.297
v4.9.298
v4.9.299
v4.9.30
v4.9.300
v4.9.301
v4.9.302
v4.9.303
v4.9.304
v4.9.305
v4.9.306
v4.9.307
v4.9.308
v4.9.309
v4.9.31
v4.9.310
v4.9.311
v4.9.312
v4.9.313
v4.9.314
v4.9.315
v4.9.316
v4.9.317
v4.9.318
v4.9.319
v4.9.32
v4.9.320
v4.9.321
v4.9.322
v4.9.323
v4.9.324
v4.9.325
v4.9.326
v4.9.327
v4.9.328
v4.9.329
v4.9.33
v4.9.330
v4.9.331
v4.9.332
v4.9.333
v4.9.334
v4.9.335
v4.9.336
v4.9.337
v4.9.34
v4.9.35
v4.9.36
v4.9.37
v4.9.38
v4.9.39
v4.9.40
v4.9.41
v4.9.42
v4.9.43
v4.9.44
v4.9.45
v4.9.46
v4.9.47
v4.9.48
v4.9.49
v4.9.50
v4.9.51
v4.9.52
v4.9.53
v4.9.54
v4.9.55
v4.9.56
v4.9.57
v4.9.58
v4.9.59
v4.9.60
v4.9.61
v4.9.62
v4.9.63
v4.9.64
v4.9.65
v4.9.66
v4.9.67
v4.9.68
v4.9.69
v4.9.70
v4.9.71
v4.9.72
v4.9.73
v4.9.74
v4.9.75
v4.9.76
v4.9.77
v4.9.78
v4.9.79
v4.9.80
v4.9.81
v4.9.82
v4.9.83
v4.9.84
v4.9.85
v4.9.86
v4.9.87
v4.9.88
v4.9.89
v4.9.90
v4.9.91
v4.9.92
v4.9.93
v4.9.94
v4.9.95
v4.9.96
v4.9.97
v4.9.98
v4.9.99

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74261.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
4.11.0
Fixed
6.18.40
Type
ECOSYSTEM
Events
Introduced
6.19.0
Fixed
7.1.5

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74261.json"