releases/5.15.202/edac-i5400-fix-snprintf-limit-calculation-in-calcula.patch

From 07e030325473714961f8b10aa875d5c335007624 Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Tue, 9 Dec 2025 17:37:04 +0300
Subject: EDAC/i5400: Fix snprintf() limit calculation in calculate_dimm_size()

From: Dan Carpenter <dan.carpenter@linaro.org>

[ Upstream commit 72f12683611344853ab030fe7d19b23970ed2bd8 ]

The snprintf() can't really overflow because we're writing a max of 42
bytes to a PAGE_SIZE buffer.  But my static checker complains because
the limit calculation doesn't take the first 11 space characters that
we wrote into the buffer into consideration.  Fix this for the sake of
correctness even though it doesn't affect runtime.

Also delete an earlier "space -= n;" which was not used.

Fixes: 68d086f89b80 ("i5400_edac: improve debug messages to better represent the filled memory")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Link: https://patch.msgid.link/ccd06b91748e7ed8e33eeb2ff1e7b98700879304.1765290801.git.dan.carpenter@linaro.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/edac/i5400_edac.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/edac/i5400_edac.c b/drivers/edac/i5400_edac.c
index f76624ee82ef7..5b1188f1b5705 100644
--- a/drivers/edac/i5400_edac.c
+++ b/drivers/edac/i5400_edac.c
@@ -1024,13 +1024,13 @@ static void calculate_dimm_size(struct i5400_pvt *pvt)
 		space -= n;
 	}
 
-	space -= n;
 	edac_dbg(2, "%s\n", mem_buffer);
 	p = mem_buffer;
 	space = PAGE_SIZE;
 
 	n = snprintf(p, space, "           ");
 	p += n;
+	space -= n;
 	for (branch = 0; branch < MAX_BRANCHES; branch++) {
 		n = snprintf(p, space, "       branch %d       | ", branch);
 		p += n;
-- 
2.51.0