From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user pointers, v1 and v2, and swaps the words they point to in hand-written assembly. l.lwz r29,0(r4) l.lwz r27,0(r5) l.sw 0(r4),r27 l.sw 0(r5),r29 The pointers are not checked with access_ok(). The four memory accesses also have no exception table entries. A caller passes a kernel address as either pointer, and the syscall reads from and writes to it directly. This gives an unprivileged process a kernel read/write primitive. It overwrites kernel data such as the sys_call_table, gaining code execution in kernel context. Check both pointers before entering the critical section. Add fixups for the four memory accesses so faults on valid but unmapped user addresses return -EFAULT. [shorne@gmail.com: fix comment style] Fixes: 9d02a4283e9c ("OpenRISC: Boot code") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Stafford Horne --- net/wireless/of.c | 127 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 127 insertions(+) create mode 100644 net/wireless/of.c (limited to 'net/wireless/of.c') diff --git a/net/wireless/of.c b/net/wireless/of.c new file mode 100644 index 000000000..99acbea3b --- /dev/null +++ b/net/wireless/of.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: ISC +/* + * Copyright (C) 2017 Rafał Miłecki + */ + +#include +#include +#include "core.h" + +static bool wiphy_freq_limits_valid_chan(struct wiphy *wiphy, + struct ieee80211_freq_range *freq_limits, + unsigned int n_freq_limits, + struct ieee80211_channel *chan) +{ + u32 bw = MHZ_TO_KHZ(20); + int i; + + for (i = 0; i < n_freq_limits; i++) { + struct ieee80211_freq_range *limit = &freq_limits[i]; + + if (cfg80211_does_bw_fit_range(limit, + MHZ_TO_KHZ(chan->center_freq), + bw)) + return true; + } + + return false; +} + +static void wiphy_freq_limits_apply(struct wiphy *wiphy, + struct ieee80211_freq_range *freq_limits, + unsigned int n_freq_limits) +{ + enum nl80211_band band; + int i; + + if (WARN_ON(!n_freq_limits)) + return; + + for (band = 0; band < NUM_NL80211_BANDS; band++) { + struct ieee80211_supported_band *sband = wiphy->bands[band]; + + if (!sband) + continue; + + for (i = 0; i < sband->n_channels; i++) { + struct ieee80211_channel *chan = &sband->channels[i]; + + if (chan->flags & IEEE80211_CHAN_DISABLED) + continue; + + if (!wiphy_freq_limits_valid_chan(wiphy, freq_limits, + n_freq_limits, + chan)) { + pr_debug("Disabling freq %d MHz as it's out of OF limits\n", + chan->center_freq); + chan->flags |= IEEE80211_CHAN_DISABLED; + } + } + } +} + +void wiphy_read_of_freq_limits(struct wiphy *wiphy) +{ + struct device *dev = wiphy_dev(wiphy); + struct device_node *np; + struct property *prop; + struct ieee80211_freq_range *freq_limits; + unsigned int n_freq_limits; + const __be32 *p; + int len, i; + int err = 0; + + if (!dev) + return; + np = dev_of_node(dev); + if (!np) + return; + + prop = of_find_property(np, "ieee80211-freq-limit", &len); + if (!prop) + return; + + if (!len || len % sizeof(u32) || len / sizeof(u32) % 2) { + dev_err(dev, "ieee80211-freq-limit wrong format"); + return; + } + n_freq_limits = len / sizeof(u32) / 2; + + freq_limits = kzalloc_objs(*freq_limits, n_freq_limits); + if (!freq_limits) { + err = -ENOMEM; + goto out_kfree; + } + + p = NULL; + for (i = 0; i < n_freq_limits; i++) { + struct ieee80211_freq_range *limit = &freq_limits[i]; + + p = of_prop_next_u32(prop, p, &limit->start_freq_khz); + if (!p) { + err = -EINVAL; + goto out_kfree; + } + + p = of_prop_next_u32(prop, p, &limit->end_freq_khz); + if (!p) { + err = -EINVAL; + goto out_kfree; + } + + if (!limit->start_freq_khz || + !limit->end_freq_khz || + limit->start_freq_khz >= limit->end_freq_khz) { + err = -EINVAL; + goto out_kfree; + } + } + + wiphy_freq_limits_apply(wiphy, freq_limits, n_freq_limits); + +out_kfree: + kfree(freq_limits); + if (err) + dev_err(dev, "Failed to get limits: %d\n", err); +} +EXPORT_SYMBOL(wiphy_read_of_freq_limits); -- cgit v1.3.1