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| author | Jeongjun Park <aha310510@gmail.com> | 2024-08-22 20:11:09 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-08-29 02:07:42 +0200 |
| commit | 0fa5e94a1811d68fbffa0725efe6d4ca62c03d12 (patch) | |
| tree | 5331c970f54958f43c867cbf0bbdba8a712420a6 /drivers/net/xen-netback/hash.c | |
| parent | Merge branch '100GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/... (diff) | |
| download | linux-0fa5e94a1811d68fbffa0725efe6d4ca62c03d12.tar.xz linux-0fa5e94a1811d68fbffa0725efe6d4ca62c03d12.zip | |
net/xen-netback: prevent UAF in xenvif_flush_hash()
During the list_for_each_entry_rcu iteration call of xenvif_flush_hash,
kfree_rcu does not exist inside the rcu read critical section, so if
kfree_rcu is called when the rcu grace period ends during the iteration,
UAF occurs when accessing head->next after the entry becomes free.
Therefore, to solve this, you need to change it to list_for_each_entry_safe.
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Link: https://patch.msgid.link/20240822181109.2577354-1-aha310510@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/net/xen-netback/hash.c')
| -rw-r--r-- | drivers/net/xen-netback/hash.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/drivers/net/xen-netback/hash.c b/drivers/net/xen-netback/hash.c index ff96f22648ef..45ddce35f6d2 100644 --- a/drivers/net/xen-netback/hash.c +++ b/drivers/net/xen-netback/hash.c @@ -95,7 +95,7 @@ static u32 xenvif_new_hash(struct xenvif *vif, const u8 *data, static void xenvif_flush_hash(struct xenvif *vif) { - struct xenvif_hash_cache_entry *entry; + struct xenvif_hash_cache_entry *entry, *n; unsigned long flags; if (xenvif_hash_cache_size == 0) @@ -103,8 +103,7 @@ static void xenvif_flush_hash(struct xenvif *vif) spin_lock_irqsave(&vif->hash.cache.lock, flags); - list_for_each_entry_rcu(entry, &vif->hash.cache.list, link, - lockdep_is_held(&vif->hash.cache.lock)) { + list_for_each_entry_safe(entry, n, &vif->hash.cache.list, link) { list_del_rcu(&entry->link); vif->hash.cache.count--; kfree_rcu(entry, rcu); |