History log of /linux-master/drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_qmath.c
Revision Date Author Comments
# f843863d 16-May-2019 Arend van Spriel <arend.vanspriel@broadcom.com>

brcmsmac: switch phy source files to using SPDX license identifier

With ISC license text in place under the LICENSES folder switch
to using the SPDX license identifier to refer to the ISC license.

Reviewed-by: Hante Meuleman <hante.meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Franky Lin <franky.lin@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>


# c9a61469 16-Jun-2018 Stefan Agner <stefan@agner.ch>

brcmsmac: fix wrap around in conversion from constant to s16

The last value in the log_table wraps around to a negative value
since s16 has a value range of -32768 to 32767. This is not what
the table intends to represent. Use the closest positive value
32767.

This fixes a warning seen with clang:
drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_qmath.c:216:2: warning:
implicit conversion from 'int' to 's16' (aka 'short') changes
value from 32768
to -32768 [-Wconstant-conversion]
32768
^~~~~
1 warning generated.

Fixes: 4c0bfeaae9f9 ("brcmsmac: fix array out-of-bounds access in qm_log10")
Cc: Tobias Regnery <tobias.regnery@gmail.com>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>


# 4c0bfeaa 21-Nov-2016 Tobias Regnery <tobias.regnery@gmail.com>

brcmsmac: fix array out-of-bounds access in qm_log10

I get the following UBSAN warning during boot on my laptop:

================================================================================
UBSAN: Undefined behaviour in drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_qmath.c:280:21
index 32 is out of range for type 's16 [32]'
CPU: 0 PID: 879 Comm: NetworkManager Not tainted 4.9.0-rc4 #28
Hardware name: LENOVO Lenovo IdeaPad N581/INVALID, BIOS 5ECN96WW(V9.01) 03/14/2013
ffff8800b74a6478 ffffffff828e59d2 0000000041b58ab3 ffffffff8398330c
ffffffff828e5920 ffff8800b74a64a0 ffff8800b74a6450 0000000000000020
1ffffffff845848c ffffed0016e94bf1 ffffffffc22c2460 000000006b9c0514
Call Trace:
[<ffffffff828e59d2>] dump_stack+0xb2/0x110
[<ffffffff828e5920>] ? _atomic_dec_and_lock+0x150/0x150
[<ffffffff82968c9d>] ubsan_epilogue+0xd/0x4e
[<ffffffff82969875>] __ubsan_handle_out_of_bounds+0xfa/0x13e
[<ffffffff8296977b>] ? __ubsan_handle_shift_out_of_bounds+0x241/0x241
[<ffffffffc0d48379>] ? bcma_host_pci_read16+0x59/0xa0 [bcma]
[<ffffffffc0d48388>] ? bcma_host_pci_read16+0x68/0xa0 [bcma]
[<ffffffffc212ad78>] ? read_phy_reg+0xe8/0x180 [brcmsmac]
[<ffffffffc2184714>] qm_log10+0x2e4/0x350 [brcmsmac]
[<ffffffffc2142eb8>] wlc_phy_init_lcnphy+0x538/0x1f20 [brcmsmac]
[<ffffffffc2142980>] ? wlc_lcnphy_periodic_cal+0x5c0/0x5c0 [brcmsmac]
[<ffffffffc1ba0c93>] ? ieee80211_open+0xb3/0x110 [mac80211]
[<ffffffff82f73a02>] ? sk_busy_loop+0x1e2/0x840
[<ffffffff82f7a6ce>] ? __dev_change_flags+0xae/0x220
...

The report is valid: doing the math in this function, with an input value
N=63 the variable s16tableIndex gets a value of 31. This value is used as
an index in the array log_table with 32 entries. But the next line is:

s16errorApproximation = (s16) qm_mulu16(u16offset,
(u16) (log_table[s16tableIndex + 1] -
log_table[s16tableIndex]));

With s16tableIndex + 1 we are trying an out-of-bounds access to the array.

The log_table array provides log2 values in q.15 format and the above
statement tries an error approximation with the next value. To fix this
issue add the next value to the array and update the comment accordingly.

Signed-off-by: Tobias Regnery <tobias.regnery@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>


# 05491d2c 17-Nov-2015 Kalle Valo <kvalo@codeaurora.org>

brcm80211: move under broadcom vendor directory

Part of reorganising wireless drivers directory and Kconfig. Note that I had to
edit Makefiles from subdirectories to use the new location.

Signed-off-by: Kalle Valo <kvalo@codeaurora.org>