linux-stable.git/net/wireless/scan.c, branch linux-4.4.y

cfg80211: Fix possible memory leak in function cfg80211_bss_update

2021-08-04T09:56:46+00:00

commit f9a5c358c8d26fed0cc45f2afc64633d4ba21dff upstream.

When we exceed the limit of BSS entries, this function will free the
new entry, however, at this time, it is the last door to access the
inputed ies, so these ies will be unreferenced objects and cause memory
leak.
Therefore we should free its ies before deallocating the new entry, beside
of dropping it from hidden_list.

Signed-off-by: Nguyen Dinh Phi 
Link: https://lore.kernel.org/r/20210628132334.851095-1-phind.uet@gmail.com
Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman

cfg80211: scan: drop entry from hidden_list on overflow

2021-05-22T08:38:21+00:00

commit 010bfbe768f7ecc876ffba92db30432de4997e2a upstream.

If we overflow the maximum number of BSS entries and free the
new entry, drop it from any hidden_list that it may have been
added to in the code above or in cfg80211_combine_bsses().

Reported-by: Dan Carpenter 
Link: https://lore.kernel.org/r/20210416094212.5de7d1676ad7.Ied283b0bc5f504845e7d6ab90626bdfa68bb3dc0@changeid
Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman

cfg80211: limit scan results cache size

2016-12-02T08:09:01+00:00

commit 9853a55ef1bb66d7411136046060bbfb69c714fa upstream.

It's possible to make scanning consume almost arbitrary amounts
of memory, e.g. by sending beacon frames with random BSSIDs at
high rates while somebody is scanning.

Limit the number of BSS table entries we're willing to cache to
1000, limiting maximum memory usage to maybe 4-5MB, but lower
in practice - that would be the case for having both full-sized
beacon and probe response frames for each entry; this seems not
possible in practice, so a limit of 1000 entries will likely be
closer to 0.5 MB.

Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman

cfg80211: Add multiple scan plans for scheduled scan

2015-10-13T08:35:26+00:00

Add the option to configure multiple 'scan plans' for scheduled scan.
Each 'scan plan' defines the number of scan cycles and the interval
between scans. The scan plans are executed in the order they were
configured. The last scan plan will always run infinitely and thus
defines only the interval between scans.
The maximum number of scan plans supported by the device and the
maximum number of iterations in a single scan plan are advertised
to userspace so it can configure the scan plans appropriately.

When scheduled scan results are received there is no way to know which
scan plan is being currently executed, so there is no way to know when
the next scan iteration will start. This is not a problem, however.
The scan start timestamp is only used for flushing old scan results,
and there is no difference between flushing all results received until
the end of the previous iteration or the start of the current one,
since no results will be received in between.

Signed-off-by: Avraham Stern 
Signed-off-by: Luca Coelho 
Signed-off-by: Johannes Berg

nl80211: allow BSS data to include CLOCK_BOOTTIME timestamp

2015-10-13T08:32:17+00:00

For location and connectivity services, userspace would often like
to know the time when the BSS was last seen. The current "last seen"
value is calculated in a way that makes it less useful, especially
if the system suspended in the meantime.

Add the ability for the driver to report a real CLOCK_BOOTTIME stamp
that can then be reported to userspace (if present).

Drivers wishing to use this must be converted to the new API to call
cfg80211_inform_bss_data() or cfg80211_inform_bss_frame_data(). They
need to ensure the reported value is accurate enough even when the
frame might have been buffered in the device (e.g. firmware.)

Signed-off-by: Dmitry Shmidt 
[modified to use struct, inlines]
Signed-off-by: Johannes Berg

cfg80211: add bss_type and privacy arguments in cfg80211_get_bss()

2015-03-03T14:56:01+00:00

802.11ad adds new a network type (PBSS) and changes the capability
field interpretation for the DMG (60G) band.
The same 2 bits that were interpreted as "ESS" and "IBSS" before are
re-used as a 2-bit field with 3 valid values (and 1 reserved). Valid
values are: "IBSS", "PBSS" (new) and "AP".

In order to get the BSS struct for the new PBSS networks, change the
cfg80211_get_bss() function to take a new enum ieee80211_bss_type
argument with the valid network types, as "capa_mask" and "capa_val"
no longer work correctly (the search must be band-aware now.)

The remaining bits in "capa_mask" and "capa_val" are used only for
privacy matching so replace those two with a privacy enum as well.

Signed-off-by: Dedy Lansky 
[rewrite commit log, tiny fixes]
Signed-off-by: Johannes Berg

cfg80211-wext: return -E2BIG when buffer can't hold full BSS entry

2015-02-28T20:31:12+00:00

When using the wext compatibility code in cfg80211, part of the IEs
can be truncated if the passed user buffer is large enough for part
of the BSS but not large enough for all of the IEs.  This can cause
an EAP network to show up as a PSK network.

Always return -E2BIG in this case to avoid truncating data.

Since this changes the control flow, use an on-stack variable for
a small buffer instead of allocating it.

Signed-off-by: James Minor 
[rework patch to error out immediately, use _check wrappers]
Signed-off-by: Johannes Berg

cfg80211-wext: export symbols only when needed

2015-02-28T20:31:09+00:00

When a fully converted cfg80211 driver needs cfg80211-wext for
userspace API purposes, the symbols need not be exported. When
other drivers (orinoco/hermes or ipw2200) are enabled, they do
need the symbols exported as they use them directly.

Make those drivers select a new CFG80211_WEXT_EXPORT Kconfig
symbol (instead of just CFG80211_WEXT) and export the functions
only if requested - this saves about 1/2k due to the size of
EXPORT_SYMBOL() itself.

Signed-off-by: Johannes Berg

nl80211: Convert sched_scan_req pointer to RCU pointer

2014-12-18T13:38:09+00:00

Because of possible races when accessing sched_scan_req pointer in
rdev, the sched_scan_req is converted to RCU pointer.

Signed-off-by: Jukka Rissanen 
Signed-off-by: Johannes Berg

cfg80211: add Intel Mobile Communications copyright

2014-09-05T11:52:06+00:00

Our legal structure changed at some point (see wikipedia), but
we forgot to immediately switch over to the new copyright
notice.

For files that we have modified in the time since the change,
add the proper copyright notice now.

Signed-off-by: Johannes Berg 
Signed-off-by: Emmanuel Grumbach 
Signed-off-by: Johannes Berg