Affected: Alpaquita:23: linux-lts, Alpaquita:25: linux-lts, Alpaquita:stream: linux-lts

In the Linux kernel, the following vulnerability has been resolved:

staging: rtl8723bs: fix OOB read in rtw_restruct_wmm_ie()

rtw_restruct_wmm_ie() scans in_ie for a WMM IE with:

while (i < in_len) { ... if (i + 5 < in_len && in_ie[i] == 0xDD && ...) { ... break; } i += (in_ie[i + 1] + 2); /* to the next IE element */ }

When the "i + 5 < in_len" match check fails simply because i is within 5 bytes of the end of the buffer (i.e. no WMM IE was found near the tail of in_ie), execution falls through to "i += (in_ie[i + 1] + 2)", which reads in_ie[i + 1]. If i == in_len - 1 at that point, this is a 1-byte out-of-bounds read of an attacker-influenced IE buffer built from association/scan data.

Commit a75281626fc8f ("staging: rtl8723bs: fix potential out-of-bounds read in rtw_restruct_wmm_ie") added the "i + 5 < in_len" guard to the match condition itself, but did not add an equivalent guard before the fallthrough advance, so the same class of OOB read remained reachable through the non-matching path.

Add an explicit bounds check before advancing to the next IE.

In the Linux kernel, the following vulnerability has been resolved:

staging: rtl8723bs: fix OOB read in rtw_restruct_wmm_ie()

rtw_restruct_wmm_ie() scans in_ie for a WMM IE with:

while (i < in_len) { ... if (i + 5 < in_len && in_ie[i] == 0xDD && ...) { ... break; } i += (in_ie[i + 1] + 2); /* to the next IE element */ }

When the "i + 5 < in_len" match check fails simply because i is within 5 bytes of the end of the buffer (i.e. no WMM IE was found near the tail of in_ie), execution falls through to "i += (in_ie[i + 1] + 2)", which reads in_ie[i + 1]. If i == in_len - 1 at that point, this is a 1-byte out-of-bounds read of an attacker-influenced IE buffer built from association/scan data.

Commit a75281626fc8f ("staging: rtl8723bs: fix potential out-of-bounds read in rtw_restruct_wmm_ie") added the "i + 5 < in_len" guard to the match condition itself, but did not add an equivalent guard before the fallthrough advance, so the same class of OOB read remained reachable through the non-matching path.

Add an explicit bounds check before advancing to the next IE.

kernel-devel-7.2.7-1.1 on GA media

Affected: Ubuntu:Pro:14.04:LTS: linux-azure, Ubuntu:Pro:16.04:LTS: linux-aws-hwe, Ubuntu:Pro:16.04:LTS: linux-azure, Ubuntu:Pro:16.04:LTS: linux-gcp, Ubuntu:Pro:16.04:LTS: linux-hwe, Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:Pro:16.04:LTS: linux-oracle, Ubuntu:Pro:18.04:LTS: linux, Ubuntu:Pro:18.04:LTS: linux-aws, Ubuntu:18.04:LTS: linux-aws-5.0 and 239 more

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8723bs: fix OOB read in rtw_restruct_wmm_ie() rtw_restruct_wmm_ie() scans in_ie for a WMM IE with: while (i < in_len) { ... if (i + 5 < in_len && in_ie[i] == 0xDD && ...) { ... break; } i += (in_ie[i + 1] + 2); /* to the next IE element */ } When the "i + 5 < in_len" match check fails simply because i is within 5 bytes of the end of the buffer (i.e. no WMM IE was found near the tail of in_ie), execution falls through to "i += (in_ie[i + 1] + 2)", which reads in_ie[i + 1]. If i == in_len - 1 at that point, this is a 1-byte out-of-bounds read of an attacker-influenced IE buffer built from association/scan data. Commit a75281626fc8f ("staging: rtl8723bs: fix potential out-of-bounds read in rtw_restruct_wmm_ie") added the "i + 5 < in_len" guard to the match condition itself, but did not add an equivalent guard before the fallthrough advance, so the same class of OOB read remained reachable through the non-matching path. Add an explicit bounds check before advancing to the next IE.

Ein lokaler Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service zu verursachen oder eine nicht näher spezifizierte Auswirkung zu erzielen.