CVE-2026-98169
smb: client: fix potential OOB read in smb3_enum_snapshots()
Published Oct 6, 2026 · updated Oct 15, 2026
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix potential OOB read in smb3_enum_snapshots() If snapshot_array_size is smaller than GMT_TOKEN_SIZE, smb3_enum_snapshots() sets ret_data_len to sizeof(struct smb_snapshot_array) without verifying the actual length of the server's reply. Because SMB2_ioctl() places no lower bound on the server-supplied OutputCount and allocates retbuf to exactly that length, a short reply results in ret_data_len exceeding the size of retbuf. The subsequent copy_to_user() then reads past the end of retbuf, leaking adjacent slab memory to userspace. The subsequent clamp check is ineffective as it only reduces ret_data_len. Fix this by rejecting replies shorter than sizeof(struct smb_snapshot_array) with -EIO. Note that the bound is set to the 12-byte struct size rather than the 16-byte MIN_SNAPSHOT_ARRAY_SIZE defined in MS-SMB2 3.3.5.15.1, because 12 bytes is exactly what copy_to_user() attempts to read.
Code
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Timeline
Detection, updates, and resolution for this record.
Oct 6, 2026 · OSV.dev
Detected
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix potential OOB read in smb3_enum_snapshots() If snapshot_array_size is smaller than GMT_TOKEN_SIZE, smb3_enum_snapshots() sets ret_data_len to sizeof(struct smb_snapshot_array) without verifying the actual length of the server's reply. Because SMB2_ioctl() places no lower bound on the server-supplied OutputCount an
Oct 15, 2026 · OSV.dev
Fix available
Kernel fixed in 6.1.189
Oct 15, 2026 · OSV.dev
Fix available
Kernel fixed in 6.1.189
Oct 15, 2026 · OSV.dev
Updated
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix potential OOB read in smb3_enum_snapshots() If snapshot_array_size is smaller than GMT_TOKEN_SIZE, smb3_enum_snapshots() sets ret_data_len to sizeof(struct smb_snapshot_array) without verifying the actual length of the server's reply. Because SMB2_ioctl() places no lower bound on the server-supplied OutputCount an
Affected
- Linux Kernel4.19.0 → 6.1.189