Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath5k: do not access array OOB
Vincent reports:
The ath5k driver seems to do an array-index-out-of-bounds access as shown by the UBSAN kernel message: UBSAN: array-index-out-of-bounds in drivers/net/wireless/ath/ath5k/base.c:1741:20 index 4 is out of range for type ‘ieee80211_tx_rate [4]’ … Call Trace:
dump_stack_lvl+0x5d/0x80 ubsan_epilogue+0x5/0x2b __ubsan_handle_out_of_bounds.cold+0x46/0x4b ath5k_tasklet_tx+0x4e0/0x560 [ath5k] tasklet_action_common+0xb5/0x1c0
It is real. ’ts->ts_final_idx’ can be 3 on 5212, so: info->status.rates[ts->ts_final_idx + 1].idx = -1; with the array defined as: struct ieee80211_tx_rate rates[IEEE80211_TX_MAX_RATES]; while the size is: #define IEEE80211_TX_MAX_RATES 4 is indeed bogus.
Set this ‘idx = -1’ sentinel only if the array index is less than the array size. As mac80211 will not look at rates beyond the size (IEEE80211_TX_MAX_RATES).
Note: The effect of the OOB write is negligible. It just overwrites the next member of info->status, i.e. ack_signal.
Details
- Affected product:
- Ubuntu 20.04 ELS
- Affected packages:
- linux-meta @ 5.4.0 (+1 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Debian 11 | Released |
37 kernels
|
| Debian 11 cloud | Released |
17 kernels
|
| Debian 12 | In Rollout |
40 kernels
|
| Debian 13 | Released |
7 kernels
|
| Ubuntu 22.04 | Planned | — |
| Ubuntu 24.04 | Planned | — |