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vfs: fix panic in __d_lookup() with high dentry hashtable counts

When the number of dentry cache hash table entries gets too high
(2147483648 entries), as happens by default on a 16TB system, use of a
signed integer in the dcache_init() initialization loop prevents the
dentry_hashtable from getting initialized, causing a panic in
__d_lookup().  Fix this in dcache_init() and similar areas.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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1 parent 1d6f209 commit 074b85175a43a23fdbde60f55feea636e0bf0f85 Dimitri Sivanich committed with Al Viro Feb 8, 2012
Showing with 14 additions and 12 deletions.
  1. +4 −4 fs/dcache.c
  2. +4 −4 fs/inode.c
  3. +2 −2 kernel/pid.c
  4. +1 −0 mm/page_alloc.c
  5. +3 −2 net/ipv4/tcp.c
View
@@ -2968,7 +2968,7 @@ __setup("dhash_entries=", set_dhash_entries);
static void __init dcache_init_early(void)
{
- int loop;
+ unsigned int loop;
/* If hashes are distributed across NUMA nodes, defer
* hash allocation until vmalloc space is available.
@@ -2986,13 +2986,13 @@ static void __init dcache_init_early(void)
&d_hash_mask,
0);
- for (loop = 0; loop < (1 << d_hash_shift); loop++)
+ for (loop = 0; loop < (1U << d_hash_shift); loop++)
INIT_HLIST_BL_HEAD(dentry_hashtable + loop);
}
static void __init dcache_init(void)
{
- int loop;
+ unsigned int loop;
/*
* A constructor could be added for stable state like the lists,
@@ -3016,7 +3016,7 @@ static void __init dcache_init(void)
&d_hash_mask,
0);
- for (loop = 0; loop < (1 << d_hash_shift); loop++)
+ for (loop = 0; loop < (1U << d_hash_shift); loop++)
INIT_HLIST_BL_HEAD(dentry_hashtable + loop);
}
View
@@ -1651,7 +1651,7 @@ __setup("ihash_entries=", set_ihash_entries);
*/
void __init inode_init_early(void)
{
- int loop;
+ unsigned int loop;
/* If hashes are distributed across NUMA nodes, defer
* hash allocation until vmalloc space is available.
@@ -1669,13 +1669,13 @@ void __init inode_init_early(void)
&i_hash_mask,
0);
- for (loop = 0; loop < (1 << i_hash_shift); loop++)
+ for (loop = 0; loop < (1U << i_hash_shift); loop++)
INIT_HLIST_HEAD(&inode_hashtable[loop]);
}
void __init inode_init(void)
{
- int loop;
+ unsigned int loop;
/* inode slab cache */
inode_cachep = kmem_cache_create("inode_cache",
@@ -1699,7 +1699,7 @@ void __init inode_init(void)
&i_hash_mask,
0);
- for (loop = 0; loop < (1 << i_hash_shift); loop++)
+ for (loop = 0; loop < (1U << i_hash_shift); loop++)
INIT_HLIST_HEAD(&inode_hashtable[loop]);
}
View
@@ -543,12 +543,12 @@ struct pid *find_ge_pid(int nr, struct pid_namespace *ns)
*/
void __init pidhash_init(void)
{
- int i, pidhash_size;
+ unsigned int i, pidhash_size;
pid_hash = alloc_large_system_hash("PID", sizeof(*pid_hash), 0, 18,
HASH_EARLY | HASH_SMALL,
&pidhash_shift, NULL, 4096);
- pidhash_size = 1 << pidhash_shift;
+ pidhash_size = 1U << pidhash_shift;
for (i = 0; i < pidhash_size; i++)
INIT_HLIST_HEAD(&pid_hash[i]);
View
@@ -5236,6 +5236,7 @@ void *__init alloc_large_system_hash(const char *tablename,
max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4;
do_div(max, bucketsize);
}
+ max = min(max, 0x80000000ULL);
if (numentries > max)
numentries = max;
View
@@ -3240,7 +3240,8 @@ void __init tcp_init(void)
{
struct sk_buff *skb = NULL;
unsigned long limit;
- int i, max_share, cnt;
+ int max_share, cnt;
+ unsigned int i;
unsigned long jiffy = jiffies;
BUILD_BUG_ON(sizeof(struct tcp_skb_cb) > sizeof(skb->cb));
@@ -3283,7 +3284,7 @@ void __init tcp_init(void)
&tcp_hashinfo.bhash_size,
NULL,
64 * 1024);
- tcp_hashinfo.bhash_size = 1 << tcp_hashinfo.bhash_size;
+ tcp_hashinfo.bhash_size = 1U << tcp_hashinfo.bhash_size;
for (i = 0; i < tcp_hashinfo.bhash_size; i++) {
spin_lock_init(&tcp_hashinfo.bhash[i].lock);
INIT_HLIST_HEAD(&tcp_hashinfo.bhash[i].chain);

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