GHSA-WQ7V-QV29-77H9
Vulnerability from github – Published: 2026-05-06 12:30 – Updated: 2026-05-06 12:30In the Linux kernel, the following vulnerability has been resolved:
pinctrl: mcp23s08: Disable all pin interrupts during probe
A chip being probed may have the interrupt-on-change feature enabled on some of its pins, for example after a reboot. This can cause the chip to generate interrupts for pins that don't have a registered nested handler, which leads to a kernel crash such as below:
[ 7.928897] Unable to handle kernel read from unreadable memory at virtual address 00000000000000ac [ 7.932314] Mem abort info: [ 7.935081] ESR = 0x0000000096000004 [ 7.938808] EC = 0x25: DABT (current EL), IL = 32 bits [ 7.944094] SET = 0, FnV = 0 [ 7.947127] EA = 0, S1PTW = 0 [ 7.950247] FSC = 0x04: level 0 translation fault [ 7.955101] Data abort info: [ 7.957961] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 7.963421] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 7.968447] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 7.973734] user pgtable: 4k pages, 48-bit VAs, pgdp=00000000089b7000 [ 7.980148] [00000000000000ac] pgd=0000000000000000, p4d=0000000000000000 [ 7.986913] Internal error: Oops: 0000000096000004 [#1] SMP [ 7.992545] Modules linked in: [ 8.073678] CPU: 0 UID: 0 PID: 81 Comm: irq/18-4-0025 Not tainted 7.0.0-rc6-gd2b5a1f931c8-dirty #199 [ 8.073689] Hardware name: Khadas VIM3 (DT) [ 8.073692] pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 8.094639] pc : _raw_spin_lock_irq+0x40/0x80 [ 8.098970] lr : handle_nested_irq+0x2c/0x168 [ 8.098979] sp : ffff800082b2bd20 [ 8.106599] x29: ffff800082b2bd20 x28: ffff800080107920 x27: ffff800080104d88 [ 8.106611] x26: ffff000003298080 x25: 0000000000000001 x24: 000000000000ff00 [ 8.113707] x23: 0000000000000001 x22: 0000000000000000 x21: 000000000000000e [ 8.120850] x20: 0000000000000000 x19: 00000000000000ac x18: 0000000000000000 [ 8.135046] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 [ 8.135062] x14: ffff800081567ea8 x13: ffffffffffffffff x12: 0000000000000000 [ 8.135070] x11: 00000000000000c0 x10: 0000000000000b60 x9 : ffff800080109e0c [ 8.135078] x8 : 1fffe0000069dbc1 x7 : 0000000000000001 x6 : ffff0000034ede00 [ 8.135086] x5 : 0000000000000000 x4 : ffff0000034ede08 x3 : 0000000000000001 [ 8.163460] x2 : 0000000000000000 x1 : 0000000000000001 x0 : 00000000000000ac [ 8.170560] Call trace: [ 8.180094] _raw_spin_lock_irq+0x40/0x80 (P) [ 8.184443] mcp23s08_irq+0x248/0x358 [ 8.184462] irq_thread_fn+0x34/0xb8 [ 8.184470] irq_thread+0x1a4/0x310 [ 8.195093] kthread+0x13c/0x150 [ 8.198309] ret_from_fork+0x10/0x20 [ 8.201850] Code: d65f03c0 d2800002 52800023 f9800011 (885ffc01) [ 8.207931] ---[ end trace 0000000000000000 ]---
This issue has always been present, but has been latent until commit "f9f4fda15e72" ("pinctrl: mcp23s08: init reg_defaults from HW at probe and switch cache type"), which correctly removed reg_defaults from the regmap and as a side effect changed the behavior of the interrupt handler so that the real value of the MCP_GPINTEN register is now being read from the chip instead of using a bogus 0 default value; a non-zero value for this register can trigger the invocation of a nested handler which may not exist (yet). Fix this issue by disabling all pin interrupts during initialization.
{
"affected": [],
"aliases": [
"CVE-2026-43087"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-05-06T10:16:21Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\npinctrl: mcp23s08: Disable all pin interrupts during probe\n\nA chip being probed may have the interrupt-on-change feature enabled on\nsome of its pins, for example after a reboot. This can cause the chip to\ngenerate interrupts for pins that don\u0027t have a registered nested handler,\nwhich leads to a kernel crash such as below:\n\n[ 7.928897] Unable to handle kernel read from unreadable memory at virtual address 00000000000000ac\n[ 7.932314] Mem abort info:\n[ 7.935081] ESR = 0x0000000096000004\n[ 7.938808] EC = 0x25: DABT (current EL), IL = 32 bits\n[ 7.944094] SET = 0, FnV = 0\n[ 7.947127] EA = 0, S1PTW = 0\n[ 7.950247] FSC = 0x04: level 0 translation fault\n[ 7.955101] Data abort info:\n[ 7.957961] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000\n[ 7.963421] CM = 0, WnR = 0, TnD = 0, TagAccess = 0\n[ 7.968447] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0\n[ 7.973734] user pgtable: 4k pages, 48-bit VAs, pgdp=00000000089b7000\n[ 7.980148] [00000000000000ac] pgd=0000000000000000, p4d=0000000000000000\n[ 7.986913] Internal error: Oops: 0000000096000004 [#1] SMP\n[ 7.992545] Modules linked in:\n[ 8.073678] CPU: 0 UID: 0 PID: 81 Comm: irq/18-4-0025 Not tainted 7.0.0-rc6-gd2b5a1f931c8-dirty #199\n[ 8.073689] Hardware name: Khadas VIM3 (DT)\n[ 8.073692] pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)\n[ 8.094639] pc : _raw_spin_lock_irq+0x40/0x80\n[ 8.098970] lr : handle_nested_irq+0x2c/0x168\n[ 8.098979] sp : ffff800082b2bd20\n[ 8.106599] x29: ffff800082b2bd20 x28: ffff800080107920 x27: ffff800080104d88\n[ 8.106611] x26: ffff000003298080 x25: 0000000000000001 x24: 000000000000ff00\n[ 8.113707] x23: 0000000000000001 x22: 0000000000000000 x21: 000000000000000e\n[ 8.120850] x20: 0000000000000000 x19: 00000000000000ac x18: 0000000000000000\n[ 8.135046] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000\n[ 8.135062] x14: ffff800081567ea8 x13: ffffffffffffffff x12: 0000000000000000\n[ 8.135070] x11: 00000000000000c0 x10: 0000000000000b60 x9 : ffff800080109e0c\n[ 8.135078] x8 : 1fffe0000069dbc1 x7 : 0000000000000001 x6 : ffff0000034ede00\n[ 8.135086] x5 : 0000000000000000 x4 : ffff0000034ede08 x3 : 0000000000000001\n[ 8.163460] x2 : 0000000000000000 x1 : 0000000000000001 x0 : 00000000000000ac\n[ 8.170560] Call trace:\n[ 8.180094] _raw_spin_lock_irq+0x40/0x80 (P)\n[ 8.184443] mcp23s08_irq+0x248/0x358\n[ 8.184462] irq_thread_fn+0x34/0xb8\n[ 8.184470] irq_thread+0x1a4/0x310\n[ 8.195093] kthread+0x13c/0x150\n[ 8.198309] ret_from_fork+0x10/0x20\n[ 8.201850] Code: d65f03c0 d2800002 52800023 f9800011 (885ffc01)\n[ 8.207931] ---[ end trace 0000000000000000 ]---\n\nThis issue has always been present, but has been latent until commit\n\"f9f4fda15e72\" (\"pinctrl: mcp23s08: init reg_defaults from HW at probe and\nswitch cache type\"), which correctly removed reg_defaults from the regmap\nand as a side effect changed the behavior of the interrupt handler so that\nthe real value of the MCP_GPINTEN register is now being read from the chip\ninstead of using a bogus 0 default value; a non-zero value for this\nregister can trigger the invocation of a nested handler which may not exist\n(yet).\nFix this issue by disabling all pin interrupts during initialization.",
"id": "GHSA-wq7v-qv29-77h9",
"modified": "2026-05-06T12:30:27Z",
"published": "2026-05-06T12:30:27Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43087"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/db5b8cecbdf479ad13156af750377e5b43853fab"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f8c3258541a0680a4ebc08b05b2bc5fdad3288a9"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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