In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix use-before-check of ReparseDataLength in reparse_buf_ptr()
reparse_buf_ptr() reads buf->ReparseDataLength before checking that
count covers the full fixed header:
buf = (struct reparse_data_buffer *)((u8 *)io + off);
len = sizeof(*buf); /* 8 bytes */
rdlen = le16_to_cpu(buf->ReparseDataLength); /* offset 4, 2 bytes */
if (count < len || count < rdlen + len) /* check comes after */
struct reparse_data_buffer has ReparseDataLength at offset 4. If a
server returns OutputCount < 6, the read at offset 4-5 reaches past
the end of the received data. The off+count bounds against iov_len
were already validated, but that does not protect against count being
smaller than sizeof(*buf).
Split the check: verify count >= sizeof(*buf) before reading
ReparseDataLength, then verify count covers the data region.
smb: client: fix use-before-check of ReparseDataLength in reparse_buf_ptr()
reparse_buf_ptr() reads buf->ReparseDataLength before checking that
count covers the full fixed header:
buf = (struct reparse_data_buffer *)((u8 *)io + off);
len = sizeof(*buf); /* 8 bytes */
rdlen = le16_to_cpu(buf->ReparseDataLength); /* offset 4, 2 bytes */
if (count < len || count < rdlen + len) /* check comes after */
struct reparse_data_buffer has ReparseDataLength at offset 4. If a
server returns OutputCount < 6, the read at offset 4-5 reaches past
the end of the received data. The off+count bounds against iov_len
were already validated, but that does not protect against count being
smaller than sizeof(*buf).
Split the check: verify count >= sizeof(*buf) before reading
ReparseDataLength, then verify count covers the data region.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
|||||||||
| Linux | Linux | unaffected |
|
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Advisories
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Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Fri, 11 Sep 2026 23:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: smb: client: fix use-before-check of ReparseDataLength in reparse_buf_ptr() reparse_buf_ptr() reads buf->ReparseDataLength before checking that count covers the full fixed header: buf = (struct reparse_data_buffer *)((u8 *)io + off); len = sizeof(*buf); /* 8 bytes */ rdlen = le16_to_cpu(buf->ReparseDataLength); /* offset 4, 2 bytes */ if (count < len || count < rdlen + len) /* check comes after */ struct reparse_data_buffer has ReparseDataLength at offset 4. If a server returns OutputCount < 6, the read at offset 4-5 reaches past the end of the received data. The off+count bounds against iov_len were already validated, but that does not protect against count being smaller than sizeof(*buf). Split the check: verify count >= sizeof(*buf) before reading ReparseDataLength, then verify count covers the data region. | |
| Title | smb: client: fix use-before-check of ReparseDataLength in reparse_buf_ptr() | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Projects
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MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-11T19:45:27.325Z
Reserved: 2026-09-11T19:38:34.738Z
Link: CVE-2026-89632
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-09-11T20:19:48.763
Modified: 2026-09-11T20:19:48.763
Link: CVE-2026-89632
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.