Home Home > GIT Browse
diff options
authorQuentin Casasnovas <quentin.casasnovas@oracle.com>2014-11-12 11:19:23 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-11-21 09:23:06 -0800
commit197b3975f4b079f004b02786bfa985ec276f6112 (patch)
parent84efcb2025064ad5650a476b8beab2fb2c27cc9f (diff)
regmap: fix kernel hang on regmap_bulk_write with zero val_count.
Fixes commit 2f06fa04cf35da5c24481da3ac84a2900d0b99c3 which was an incorrect backported version of commit d6b41cb06044a7d895db82bdd54f6e4219970510 upstream. If val_count is zero we return -EINVAL with map->lock_arg locked, which will deadlock the kernel next time we try to acquire this lock. This was introduced by f5942dd ("regmap: fix possible ZERO_SIZE_PTR pointer dereferencing error.") which improperly back-ported d6b41cb0. This issue was found during review of Ubuntu Trusty 3.13.0-40.68 kernel to prepare Ksplice rebootless updates. Fixes: f5942dd ("regmap: fix possible ZERO_SIZE_PTR pointer dereferencing error.") Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index f6cff3be0ed7..2f9a3d8ecbbf 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -1557,8 +1557,10 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
} else {
void *wval;
- if (!val_count)
- return -EINVAL;
+ if (!val_count) {
+ ret = -EINVAL;
+ goto out;
+ }
wval = kmemdup(val, val_count * val_bytes, GFP_KERNEL);
if (!wval) {