[PATCH V2] lightnvm: protect target type list with correct locks
STALE3297d
From: Rakesh Pandit <hidden>
Date: 2017-09-16 18:39:56
Also in:
lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
nvm_tgt_types list was protected by wrong lock for NVM_INFO ioctl call
and can race with addition or removal of target types. Also
unregistering target type was not protected correctly.
Fixes: 5cd907853 ("lightnvm: remove nested lock conflict with mm")
Signed-off-by: Rakesh Pandit <redacted>
---
V2: also add correct lock while unregistering and fix "Fixes" tag at
end. Note I found these while investigating another issue and
skimming the core code but worth fixing.
drivers/lightnvm/core.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index 9f9a137..1b8338d 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c@@ -589,9 +589,9 @@ void nvm_unregister_tgt_type(struct nvm_tgt_type *tt) if (!tt) return; - down_write(&nvm_lock); + down_write(&nvm_tgtt_lock); list_del(&tt->list); - up_write(&nvm_lock); + up_write(&nvm_tgtt_lock); } EXPORT_SYMBOL(nvm_unregister_tgt_type);
@@ -1190,7 +1190,7 @@ static long nvm_ioctl_info(struct file *file, void __user *arg) info->version[1] = NVM_VERSION_MINOR; info->version[2] = NVM_VERSION_PATCH; - down_write(&nvm_lock); + down_write(&nvm_tgtt_lock); list_for_each_entry(tt, &nvm_tgt_types, list) { struct nvm_ioctl_info_tgt *tgt = &info->tgts[tgt_iter];
@@ -1203,7 +1203,7 @@ static long nvm_ioctl_info(struct file *file, void __user *arg) } info->tgtsize = tgt_iter; - up_write(&nvm_lock); + up_write(&nvm_tgtt_lock); if (copy_to_user(arg, info, sizeof(struct nvm_ioctl_info))) { kfree(info);
--
2.7.4