aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/base/regmap
diff options
context:
space:
mode:
authorMark Brown <broonie@opensource.wolfsonmicro.com>2012-12-11 01:14:11 +0900
committerBen Hutchings <ben@decadent.org.uk>2013-01-03 03:33:32 +0000
commit71f1e737a5ab8cc3c1384117222ef82c99bc056d (patch)
tree0869ca036b3e01d7efc00318a8a29d5c58775f8c /drivers/base/regmap
parent19afa7002ed6c2cf51c85ce5e2c2eaaf55e771c3 (diff)
downloadkernel_samsung_smdk4412-71f1e737a5ab8cc3c1384117222ef82c99bc056d.zip
kernel_samsung_smdk4412-71f1e737a5ab8cc3c1384117222ef82c99bc056d.tar.gz
kernel_samsung_smdk4412-71f1e737a5ab8cc3c1384117222ef82c99bc056d.tar.bz2
regmap: debugfs: Avoid overflows for very small reads
commit db04328c167ff8e7c57f4a3532214aeada3a82fd upstream. 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 <broonie@opensource.wolfsonmicro.com> [bwh: Backported to 3.2: formatted length is tot_len] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'drivers/base/regmap')
-rw-r--r--drivers/base/regmap/regmap-debugfs.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c
index 6f39747..cd252e0 100644
--- a/drivers/base/regmap/regmap-debugfs.c
+++ b/drivers/base/regmap/regmap-debugfs.c
@@ -67,7 +67,7 @@ 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 */