CVE-2026-63910
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: dma-buf: fix UAF in dma_buf_fd() tracepoint Once FD_ADD() returns, the fd is live in the file descriptor table and a thread sharing that table can close() it before DMA_BUF_TRACE() runs. The close drops the last reference, __fput() frees the dma_buf, and the tracepoint then dereferences dmabuf to take dmabuf->name_lock -- slab-use-after-free. Split FD_ADD() back into get_unused_fd_flags() + fd_install() and emit the tracepoint between them. While the fdtable slot is reserved with a NULL file pointer, a racing close() returns -EBADF without entering __fput(), so the dma_buf stays alive across the trace. Same approach as commit 2d76319c4cbb ("dma-buf: fix UAF in dma_buf_put() tracepoint"). This undoes the FD_ADD() conversion done in commit 34dfce523c90 ("dma: convert dma_buf_fd() to FD_ADD()"); FD_ADD() has no place to hook the tracepoint safely.
Severity
HIGH
CVSS score
7.8
(v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-19 16:17:08.857000
Last modified
2026-10-30 14:29:37.863000
View original CVE JSON
{
"id": "CVE-2026-63910",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-07-19T16:17:08.857",
"lastModified": "2026-10-30T14:29:37.863",
"vulnStatus": "Analyzed",
"cveTags": [],
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{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndma-buf: fix UAF in dma_buf_fd() tracepoint\n\nOnce FD_ADD() returns, the fd is live in the file descriptor table\nand a thread sharing that table can close() it before DMA_BUF_TRACE()\nruns. The close drops the last reference, __fput() frees the dma_buf,\nand the tracepoint then dereferences dmabuf to take dmabuf->name_lock\n-- slab-use-after-free.\n\nSplit FD_ADD() back into get_unused_fd_flags() + fd_install() and\nemit the tracepoint between them. While the fdtable slot is reserved\nwith a NULL file pointer, a racing close() returns -EBADF without\nentering __fput(), so the dma_buf stays alive across the trace. Same\napproach as commit 2d76319c4cbb (\"dma-buf: fix UAF in dma_buf_put()\ntracepoint\").\n\nThis undoes the FD_ADD() conversion done in commit 34dfce523c90\n(\"dma: convert dma_buf_fd() to FD_ADD()\"); FD_ADD() has no place to\nhook the tracepoint safely."
}
],
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{
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"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
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],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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"baseScore": 7.8,
"baseSeverity": "HIGH",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
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},
"weaknesses": [
{
"source": "[email protected]",
"type": "Primary",
"description": [
{
"lang": "en",
"value": "CWE-416"
}
]
}
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"configurations": [
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