| Message ID | 20230116152235.1433484-1-aaron.ma@canonical.com (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Kalle Valo |
| Headers | show |
| Series | wifi: mt76: mt7921: fix error code of return in mt7921_acpi_read | expand |
Aaron Ma <aaron.ma@canonical.com> writes: > Kernel NULL pointer dereference when ACPI SAR table isn't implemented well. > Fix the error code of return to mark the ACPI SAR table as invalid. > > [ 5.077128] mt7921e 0000:06:00.0: sar cnt = 0 > [ 5.077381] BUG: kernel NULL pointer dereference, address: > 0000000000000004 > [ 5.077630] #PF: supervisor read access in kernel mode > [ 5.077883] #PF: error_code(0x0000) - not-present page > [ 5.078138] PGD 0 P4D 0 > [ 5.078398] Oops: 0000 [#1] PREEMPT SMP NOPTI > [ 5.079202] RIP: 0010:mt7921_init_acpi_sar+0x106/0x220 > [mt7921_common] > ... > [ 5.080786] Call Trace: > [ 5.080786] <TASK> > [ 5.080786] mt7921_register_device+0x37d/0x490 [mt7921_common] > [ 5.080786] mt7921_pci_probe.part.0+0x2ee/0x310 [mt7921e] > [ 5.080786] mt7921_pci_probe+0x52/0x70 [mt7921e] > [ 5.080786] local_pci_probe+0x47/0x90 > [ 5.080786] pci_call_probe+0x55/0x190 > [ 5.080786] pci_device_probe+0x84/0x120 > > Fixes: f965333e491e ("mt76: mt7921: introduce ACPI SAR support") > Signed-off-by: Aaron Ma <aaron.ma@canonical.com> Felix, if this is ok should this go to v6.2?
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/acpi_sar.c b/drivers/net/wireless/mediatek/mt76/mt7921/acpi_sar.c index 47e034a9b003..ed9241d4aa64 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/acpi_sar.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/acpi_sar.c @@ -33,14 +33,17 @@ mt7921_acpi_read(struct mt7921_dev *dev, u8 *method, u8 **tbl, u32 *len) sar_root->package.elements[0].type != ACPI_TYPE_INTEGER) { dev_err(mdev->dev, "sar cnt = %d\n", sar_root->package.count); + ret = -EINVAL; goto free; } if (!*tbl) { *tbl = devm_kzalloc(mdev->dev, sar_root->package.count, GFP_KERNEL); - if (!*tbl) + if (!*tbl) { + ret = -ENOMEM; goto free; + } } if (len) *len = sar_root->package.count; @@ -52,9 +55,9 @@ mt7921_acpi_read(struct mt7921_dev *dev, u8 *method, u8 **tbl, u32 *len) break; *(*tbl + i) = (u8)sar_unit->integer.value; } -free: ret = (i == sar_root->package.count) ? 0 : -EINVAL; +free: kfree(sar_root); return ret;
Kernel NULL pointer dereference when ACPI SAR table isn't implemented well. Fix the error code of return to mark the ACPI SAR table as invalid. [ 5.077128] mt7921e 0000:06:00.0: sar cnt = 0 [ 5.077381] BUG: kernel NULL pointer dereference, address: 0000000000000004 [ 5.077630] #PF: supervisor read access in kernel mode [ 5.077883] #PF: error_code(0x0000) - not-present page [ 5.078138] PGD 0 P4D 0 [ 5.078398] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 5.079202] RIP: 0010:mt7921_init_acpi_sar+0x106/0x220 [mt7921_common] ... [ 5.080786] Call Trace: [ 5.080786] <TASK> [ 5.080786] mt7921_register_device+0x37d/0x490 [mt7921_common] [ 5.080786] mt7921_pci_probe.part.0+0x2ee/0x310 [mt7921e] [ 5.080786] mt7921_pci_probe+0x52/0x70 [mt7921e] [ 5.080786] local_pci_probe+0x47/0x90 [ 5.080786] pci_call_probe+0x55/0x190 [ 5.080786] pci_device_probe+0x84/0x120 Fixes: f965333e491e ("mt76: mt7921: introduce ACPI SAR support") Signed-off-by: Aaron Ma <aaron.ma@canonical.com> --- drivers/net/wireless/mediatek/mt76/mt7921/acpi_sar.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)