diff options
author | Michal Kazior <michal.kazior@tieto.com> | 2015-06-15 11:46:42 (GMT) |
---|---|---|
committer | Kalle Valo <kvalo@qca.qualcomm.com> | 2015-06-16 10:10:50 (GMT) |
commit | aeae5b4cd9185b0dc72f6d6102cf45073bfbc974 (patch) | |
tree | cf8152ef7147b6e9cdddaf0894c895e2127dee21 /drivers | |
parent | c702534a23d61deaa0565ef0495ab866c06c4325 (diff) | |
download | linux-aeae5b4cd9185b0dc72f6d6102cf45073bfbc974.tar.xz |
ath10k: prevent debugfs mmio access crash kernel
It was possible to force an out of bounds MMIO
read/write via debugfs. E.g. on QCA988X this could
be triggered with:
echo 0x2080e0 | tee /sys/kernel/debug/ieee80211/*/ath10k/reg_addr
cat /sys/kernel/debug/ieee80211/*/ath10k/reg_value
BUG: unable to handle kernel paging request at ffffc90001e080e0
IP: [<ffffffff8135c860>] ioread32+0x40/0x50
...
Call Trace:
[<ffffffffa00d0c7f>] ? ath10k_pci_read32+0x4f/0x70 [ath10k_pci]
[<ffffffffa0080f50>] ath10k_reg_value_read+0x90/0xf0 [ath10k_core]
[<ffffffff8115c2c1>] ? handle_mm_fault+0xa91/0x1050
[<ffffffff81189758>] __vfs_read+0x28/0xe0
[<ffffffff812e4694>] ? security_file_permission+0x84/0xa0
[<ffffffff81189ce3>] ? rw_verify_area+0x53/0x100
[<ffffffff81189e1a>] vfs_read+0x8a/0x140
[<ffffffff8118acb9>] SyS_read+0x49/0xb0
[<ffffffff8104e39c>] ? trace_do_page_fault+0x3c/0xc0
[<ffffffff8196596e>] system_call_fastpath+0x12/0x71
Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/net/wireless/ath/ath10k/pci.c | 13 | ||||
-rw-r--r-- | drivers/net/wireless/ath/ath10k/pci.h | 1 |
2 files changed, 14 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath/ath10k/pci.c b/drivers/net/wireless/ath/ath10k/pci.c index ea656e0..4176517 100644 --- a/drivers/net/wireless/ath/ath10k/pci.c +++ b/drivers/net/wireless/ath/ath10k/pci.c @@ -479,6 +479,12 @@ void ath10k_pci_write32(struct ath10k *ar, u32 offset, u32 value) struct ath10k_pci *ar_pci = ath10k_pci_priv(ar); int ret; + if (unlikely(offset + sizeof(value) > ar_pci->mem_len)) { + ath10k_warn(ar, "refusing to write mmio out of bounds at 0x%08x - 0x%08zx (max 0x%08zx)\n", + offset, offset + sizeof(value), ar_pci->mem_len); + return; + } + ret = ath10k_pci_wake(ar); if (ret) { ath10k_warn(ar, "failed to wake target for write32 of 0x%08x at 0x%08x: %d\n", @@ -496,6 +502,12 @@ u32 ath10k_pci_read32(struct ath10k *ar, u32 offset) u32 val; int ret; + if (unlikely(offset + sizeof(val) > ar_pci->mem_len)) { + ath10k_warn(ar, "refusing to read mmio out of bounds at 0x%08x - 0x%08zx (max 0x%08zx)\n", + offset, offset + sizeof(val), ar_pci->mem_len); + return 0; + } + ret = ath10k_pci_wake(ar); if (ret) { ath10k_warn(ar, "failed to wake target for read32 at 0x%08x: %d\n", @@ -2679,6 +2691,7 @@ static int ath10k_pci_claim(struct ath10k *ar) pci_set_master(pdev); /* Arrange for access to Target SoC registers. */ + ar_pci->mem_len = pci_resource_len(pdev, BAR_NUM); ar_pci->mem = pci_iomap(pdev, BAR_NUM, 0); if (!ar_pci->mem) { ath10k_err(ar, "failed to iomap BAR%d\n", BAR_NUM); diff --git a/drivers/net/wireless/ath/ath10k/pci.h b/drivers/net/wireless/ath/ath10k/pci.h index d7696dd..eea0a01 100644 --- a/drivers/net/wireless/ath/ath10k/pci.h +++ b/drivers/net/wireless/ath/ath10k/pci.h @@ -162,6 +162,7 @@ struct ath10k_pci { struct device *dev; struct ath10k *ar; void __iomem *mem; + size_t mem_len; /* * Number of MSI interrupts granted, 0 --> using legacy PCI line |