net: phy: register phy led_triggers during probe to avoid AB-BA deadlock
Summary
| CVE | CVE-2026-23368 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-03-25 11:16:36 UTC |
| Updated | 2026-04-18 09:16:21 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: net: phy: register phy led_triggers during probe to avoid AB-BA deadlock There is an AB-BA deadlock when both LEDS_TRIGGER_NETDEV and LED_TRIGGER_PHY are enabled: [ 1362.049207] [<8054e4b8>] led_trigger_register+0x5c/0x1fc <-- Trying to get lock "triggers_list_lock" via down_write(&triggers_list_lock); [ 1362.054536] [<80662830>] phy_led_triggers_register+0xd0/0x234 [ 1362.060329] [<8065e200>] phy_attach_direct+0x33c/0x40c [ 1362.065489] [<80651fc4>] phylink_fwnode_phy_connect+0x15c/0x23c [ 1362.071480] [<8066ee18>] mtk_open+0x7c/0xba0 [ 1362.075849] [<806d714c>] __dev_open+0x280/0x2b0 [ 1362.080384] [<806d7668>] __dev_change_flags+0x244/0x24c [ 1362.085598] [<806d7698>] dev_change_flags+0x28/0x78 [ 1362.090528] [<807150e4>] dev_ioctl+0x4c0/0x654 <-- Hold lock "rtnl_mutex" by calling rtnl_lock(); [ 1362.094985] [<80694360>] sock_ioctl+0x2f4/0x4e0 [ 1362.099567] [<802e9c4c>] sys_ioctl+0x32c/0xd8c [ 1362.104022] [<80014504>] syscall_common+0x34/0x58 Here LED_TRIGGER_PHY is registering LED triggers during phy_attach while holding RTNL and then taking triggers_list_lock. [ 1362.191101] [<806c2640>] register_netdevice_notifier+0x60/0x168 <-- Trying to get lock "rtnl_mutex" via rtnl_lock(); [ 1362.197073] [<805504ac>] netdev_trig_activate+0x194/0x1e4 [ 1362.202490] [<8054e28c>] led_trigger_set+0x1d4/0x360 <-- Hold lock "triggers_list_lock" by down_read(&triggers_list_lock); [ 1362.207511] [<8054eb38>] led_trigger_write+0xd8/0x14c [ 1362.212566] [<80381d98>] sysfs_kf_bin_write+0x80/0xbc [ 1362.217688] [<8037fcd8>] kernfs_fop_write_iter+0x17c/0x28c [ 1362.223174] [<802cbd70>] vfs_write+0x21c/0x3c4 [ 1362.227712] [<802cc0c4>] ksys_write+0x78/0x12c [ 1362.232164] [<80014504>] syscall_common+0x34/0x58 Here LEDS_TRIGGER_NETDEV is being enabled on an LED. It first takes triggers_list_lock and then RTNL. A classical AB-BA deadlock. phy_led_triggers_registers() does not require the RTNL, it does not make any calls into the network stack which require protection. There is also no requirement the PHY has been attached to a MAC, the triggers only make use of phydev state. This allows the call to phy_led_triggers_registers() to be placed elsewhere. PHY probe() and release() don't hold RTNL, so solving the AB-BA deadlock. |
Risk And Classification
EPSS: 0.000320000 probability, percentile 0.090980000 (date 2026-04-18)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 2b01518eabace18f7ec8b4cafd52082303080dca git | Not specified |
| CNA | Linux | Linux | affected 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 305afdd02ff3e694c165457793104710ec0728e5 git | Not specified |
| CNA | Linux | Linux | affected 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 c6ffc2d2338d325e1edd0c702e3ee623aa5fdc6a git | Not specified |
| CNA | Linux | Linux | affected 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 c33523b8fd2d4c504ada18cd93f511f2a8f84217 git | Not specified |
| CNA | Linux | Linux | affected 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 241cd64cf2e32b28ead151b1795cd8fef2b6e482 git | Not specified |
| CNA | Linux | Linux | affected 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 2764dcb3c35de4410f642afc62cf979727470575 git | Not specified |
| CNA | Linux | Linux | affected 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 cde2d0b5ab5d03b5b6f17d4f654d8b30ccf36757 git | Not specified |
| CNA | Linux | Linux | affected 06f502f57d0d7728f9fa0f157ec5e4111ddb98f6 c8dbdc6e380e7e96a51706db3e4b7870d8a9402d git | Not specified |
| CNA | Linux | Linux | affected 4.16 | Not specified |
| CNA | Linux | Linux | unaffected 4.16 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.253 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.203 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.167 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.130 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.78 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.17 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.19.7 6.19.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/2764dcb3c35de4410f642afc62cf979727470575 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/c6ffc2d2338d325e1edd0c702e3ee623aa5fdc6a | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/cde2d0b5ab5d03b5b6f17d4f654d8b30ccf36757 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/c8dbdc6e380e7e96a51706db3e4b7870d8a9402d | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/c33523b8fd2d4c504ada18cd93f511f2a8f84217 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/305afdd02ff3e694c165457793104710ec0728e5 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/241cd64cf2e32b28ead151b1795cd8fef2b6e482 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/2b01518eabace18f7ec8b4cafd52082303080dca | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.