[PATCH AUTOSEL 4.19 196/237] wil6210: fix debugfs memory access alignment
From: Sasha Levin <sashal@kernel.org>
Date: 2019-11-16 16:16:17
Also in:
linux-wireless, lkml, stable
Subsystem:
atheros ath generic utilities, the rest, wilocity wil6210 wireless driver · Maintainers:
Jeff Johnson, Linus Torvalds
From: Ahmad Masri <redacted> [ Upstream commit 84ec040d0fb25197584d28a0dedc355503cd19b9 ] All wil6210 device memory access should be 4 bytes aligned. In io blob wil6210 did not force alignment for read function, this caused alignment fault on some platforms. Fixing that by accessing all 4 lower bytes and return to host the requested data. Signed-off-by: Ahmad Masri <redacted> Signed-off-by: Maya Erez <redacted> Signed-off-by: Kalle Valo <redacted> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/net/wireless/ath/wil6210/debugfs.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/net/wireless/ath/wil6210/debugfs.c b/drivers/net/wireless/ath/wil6210/debugfs.c
index 51c3330bc316f..12b8cb698f64d 100644
--- a/drivers/net/wireless/ath/wil6210/debugfs.c
+++ b/drivers/net/wireless/ath/wil6210/debugfs.c@@ -662,10 +662,10 @@ static ssize_t wil_read_file_ioblob(struct file *file, char __user *user_buf, enum { max_count = 4096 }; struct wil_blob_wrapper *wil_blob = file->private_data; struct wil6210_priv *wil = wil_blob->wil; - loff_t pos = *ppos; + loff_t aligned_pos, pos = *ppos; size_t available = wil_blob->blob.size; void *buf; - size_t ret; + size_t unaligned_bytes, aligned_count, ret; int rc; if (test_bit(wil_status_suspending, wil_blob->wil->status) ||
@@ -683,7 +683,12 @@ static ssize_t wil_read_file_ioblob(struct file *file, char __user *user_buf, if (count > max_count) count = max_count; - buf = kmalloc(count, GFP_KERNEL); + /* set pos to 4 bytes aligned */ + unaligned_bytes = pos % 4; + aligned_pos = pos - unaligned_bytes; + aligned_count = count + unaligned_bytes; + + buf = kmalloc(aligned_count, GFP_KERNEL); if (!buf) return -ENOMEM;
@@ -694,9 +699,9 @@ static ssize_t wil_read_file_ioblob(struct file *file, char __user *user_buf, } wil_memcpy_fromio_32(buf, (const void __iomem *) - wil_blob->blob.data + pos, count); + wil_blob->blob.data + aligned_pos, aligned_count); - ret = copy_to_user(user_buf, buf, count); + ret = copy_to_user(user_buf, buf + unaligned_bytes, count); wil_pm_runtime_put(wil);
--
2.20.1