v2: adding changelog about modification for 3.4.x and 3.7.x stable. v1: s/map->debugfs_tot_len/tot_len/ to adjust for stable code base.
>From db04328c167ff8e7c57f4a3532214aeada3a82fd Mon Sep 17 00:00:00 2001 From: Mark Brown <[email protected]> Date: Tue, 11 Dec 2012 01:14:11 +0900 Subject: [PATCH] regmap: debugfs: Avoid overflows for very small reads If count is less than the size of a register then we may hit integer wraparound when trying to move backwards to check if we're still in the buffer. Instead move the position forwards to check if it's still in the buffer, we are unlikely to be able to allocate a buffer sufficiently big to overflow here. Signed-off-by: Mark Brown <[email protected]> Cc: [email protected] Signed-off-by: CAI Qian <[email protected]> diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c index bb1ff17..c394041 100644 --- a/drivers/base/regmap/regmap-debugfs.c +++ b/drivers/base/regmap/regmap-debugfs.c @@ -90,7 +90,7 @@ static ssize_t regmap_map_read_file(struct file *file, char __user *user_buf, /* If we're in the region the user is trying to read */ if (p >= *ppos) { /* ...but not beyond it */ - if (buf_pos >= count - 1 - tot_len) + if (buf_pos + 1 + tot_len >= count) break; /* Format the register */ -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
