The bug was found during fuzzing. Stacktrace locates it in
ath5k_eeprom_convert_pcal_info_5111.
When none of the curve is selected in the loop, idx can go
up to AR5K_EEPROM_N_PD_CURVES. The line makes pd out of bound.
pd = &chinfo[pier].pd_curves[idx];
There are many OOB writes using pd later in the code. So I
added a sanity check for idx. Checks for other loops involving
AR5K_EEPROM_N_PD_CURVES are not needed as the loop index is not
used outside the loops.
The patch is NOT tested with real device.
The following is the fuzzing report
BUG: KASAN: slab-out-of-bounds in ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
Write of size 1 at addr ffff8880174a4d60 by task modprobe/214
CPU: 0 PID: 214 Comm: modprobe Not tainted 5.6.0 #1
Call Trace:
dump_stack+0x76/0xa0
print_address_description.constprop.0+0x16/0x200
? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
__kasan_report.cold+0x37/0x7c
? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
kasan_report+0xe/0x20
ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
? apic_timer_interrupt+0xa/0x20
? ath5k_eeprom_init_11a_pcal_freq+0xbc0/0xbc0 [ath5k]
? ath5k_pci_eeprom_read+0x228/0x3c0 [ath5k]
ath5k_eeprom_init+0x2513/0x6290 [ath5k]
? ath5k_eeprom_init_11a_pcal_freq+0xbc0/0xbc0 [ath5k]
? usleep_range+0xb8/0x100
? apic_timer_interrupt+0xa/0x20
? ath5k_eeprom_read_pcal_info_2413+0x2f20/0x2f20 [ath5k]
ath5k_hw_init+0xb60/0x1970 [ath5k]
ath5k_init_ah+0x6fe/0x2530 [ath5k]
? kasprintf+0xa6/0xe0
? ath5k_stop+0x140/0x140 [ath5k]
? _dev_notice+0xf6/0xf6
? apic_timer_interrupt+0xa/0x20
ath5k_pci_probe.cold+0x29a/0x3d6 [ath5k]
? ath5k_pci_eeprom_read+0x3c0/0x3c0 [ath5k]
? mutex_lock+0x89/0xd0
? ath5k_pci_eeprom_read+0x3c0/0x3c0 [ath5k]
local_pci_probe+0xd3/0x160
pci_device_probe+0x23f/0x3e0
? pci_device_remove+0x280/0x280
? pci_device_remove+0x280/0x280
really_probe+0x209/0x5d0
Reported-by: Brendan Dolan-Gavitt <[email protected]>
Signed-off-by: Zekun Shen <[email protected]>
---
drivers/net/wireless/ath/ath5k/eeprom.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/net/wireless/ath/ath5k/eeprom.c b/drivers/net/wireless/ath/ath5k/eeprom.c
index 1fbc2c198..d444b3d70 100644
--- a/drivers/net/wireless/ath/ath5k/eeprom.c
+++ b/drivers/net/wireless/ath/ath5k/eeprom.c
@@ -746,6 +746,9 @@ ath5k_eeprom_convert_pcal_info_5111(struct ath5k_hw *ah, int mode,
}
}
+ if (idx == AR5K_EEPROM_N_PD_CURVES)
+ goto err_out;
+
ee->ee_pd_gains[mode] = 1;
pd = &chinfo[pier].pd_curves[idx];
--
2.25.1
On Sun, Dec 26, 2021 at 10:12:13PM -0500, Zekun Shen wrote:
> The bug was found during fuzzing. Stacktrace locates it in
> ath5k_eeprom_convert_pcal_info_5111.
> When none of the curve is selected in the loop, idx can go
> up to AR5K_EEPROM_N_PD_CURVES. The line makes pd out of bound.
> pd = &chinfo[pier].pd_curves[idx];
>
> There are many OOB writes using pd later in the code. So I
> added a sanity check for idx. Checks for other loops involving
> AR5K_EEPROM_N_PD_CURVES are not needed as the loop index is not
> used outside the loops.
>
> The patch is NOT tested with real device.
>
> The following is the fuzzing report
>
> BUG: KASAN: slab-out-of-bounds in ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
> Write of size 1 at addr ffff8880174a4d60 by task modprobe/214
>
> CPU: 0 PID: 214 Comm: modprobe Not tainted 5.6.0 #1
> Call Trace:
> dump_stack+0x76/0xa0
> print_address_description.constprop.0+0x16/0x200
> ? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
> ? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
> __kasan_report.cold+0x37/0x7c
> ? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
> kasan_report+0xe/0x20
> ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
> ? apic_timer_interrupt+0xa/0x20
> ? ath5k_eeprom_init_11a_pcal_freq+0xbc0/0xbc0 [ath5k]
> ? ath5k_pci_eeprom_read+0x228/0x3c0 [ath5k]
> ath5k_eeprom_init+0x2513/0x6290 [ath5k]
> ? ath5k_eeprom_init_11a_pcal_freq+0xbc0/0xbc0 [ath5k]
> ? usleep_range+0xb8/0x100
> ? apic_timer_interrupt+0xa/0x20
> ? ath5k_eeprom_read_pcal_info_2413+0x2f20/0x2f20 [ath5k]
> ath5k_hw_init+0xb60/0x1970 [ath5k]
> ath5k_init_ah+0x6fe/0x2530 [ath5k]
> ? kasprintf+0xa6/0xe0
> ? ath5k_stop+0x140/0x140 [ath5k]
> ? _dev_notice+0xf6/0xf6
> ? apic_timer_interrupt+0xa/0x20
> ath5k_pci_probe.cold+0x29a/0x3d6 [ath5k]
> ? ath5k_pci_eeprom_read+0x3c0/0x3c0 [ath5k]
> ? mutex_lock+0x89/0xd0
> ? ath5k_pci_eeprom_read+0x3c0/0x3c0 [ath5k]
> local_pci_probe+0xd3/0x160
> pci_device_probe+0x23f/0x3e0
> ? pci_device_remove+0x280/0x280
> ? pci_device_remove+0x280/0x280
> really_probe+0x209/0x5d0
>
> Reported-by: Brendan Dolan-Gavitt <[email protected]>
> Signed-off-by: Zekun Shen <[email protected]>
Acked-by: Luis Chamberlain <[email protected]>
Luis
Zekun Shen <[email protected]> wrote:
> The bug was found during fuzzing. Stacktrace locates it in
> ath5k_eeprom_convert_pcal_info_5111.
> When none of the curve is selected in the loop, idx can go
> up to AR5K_EEPROM_N_PD_CURVES. The line makes pd out of bound.
> pd = &chinfo[pier].pd_curves[idx];
>
> There are many OOB writes using pd later in the code. So I
> added a sanity check for idx. Checks for other loops involving
> AR5K_EEPROM_N_PD_CURVES are not needed as the loop index is not
> used outside the loops.
>
> The patch is NOT tested with real device.
>
> The following is the fuzzing report
>
> BUG: KASAN: slab-out-of-bounds in ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
> Write of size 1 at addr ffff8880174a4d60 by task modprobe/214
>
> CPU: 0 PID: 214 Comm: modprobe Not tainted 5.6.0 #1
> Call Trace:
> dump_stack+0x76/0xa0
> print_address_description.constprop.0+0x16/0x200
> ? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
> ? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
> __kasan_report.cold+0x37/0x7c
> ? ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
> kasan_report+0xe/0x20
> ath5k_eeprom_read_pcal_info_5111+0x126a/0x1390 [ath5k]
> ? apic_timer_interrupt+0xa/0x20
> ? ath5k_eeprom_init_11a_pcal_freq+0xbc0/0xbc0 [ath5k]
> ? ath5k_pci_eeprom_read+0x228/0x3c0 [ath5k]
> ath5k_eeprom_init+0x2513/0x6290 [ath5k]
> ? ath5k_eeprom_init_11a_pcal_freq+0xbc0/0xbc0 [ath5k]
> ? usleep_range+0xb8/0x100
> ? apic_timer_interrupt+0xa/0x20
> ? ath5k_eeprom_read_pcal_info_2413+0x2f20/0x2f20 [ath5k]
> ath5k_hw_init+0xb60/0x1970 [ath5k]
> ath5k_init_ah+0x6fe/0x2530 [ath5k]
> ? kasprintf+0xa6/0xe0
> ? ath5k_stop+0x140/0x140 [ath5k]
> ? _dev_notice+0xf6/0xf6
> ? apic_timer_interrupt+0xa/0x20
> ath5k_pci_probe.cold+0x29a/0x3d6 [ath5k]
> ? ath5k_pci_eeprom_read+0x3c0/0x3c0 [ath5k]
> ? mutex_lock+0x89/0xd0
> ? ath5k_pci_eeprom_read+0x3c0/0x3c0 [ath5k]
> local_pci_probe+0xd3/0x160
> pci_device_probe+0x23f/0x3e0
> ? pci_device_remove+0x280/0x280
> ? pci_device_remove+0x280/0x280
> really_probe+0x209/0x5d0
>
> Reported-by: Brendan Dolan-Gavitt <[email protected]>
> Signed-off-by: Zekun Shen <[email protected]>
> Signed-off-by: Kalle Valo <[email protected]>
Patch applied to ath-next branch of ath.git, thanks.
564d4eceb97e ath5k: fix OOB in ath5k_eeprom_read_pcal_info_5111
--
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches