From: Dimitri Sivanich Date: Fri, 10 Aug 2012 11:46:56 +0000 (-0700) Subject: vfs: fix panic in __d_lookup() with high dentry hashtable counts X-Git-Tag: v2.6.39-400.9.0~425^2~2 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=4def6f6bec699437a7d7d8532f46e23a9e70dbea;p=users%2Fjedix%2Flinux-maple.git 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 Acked-by: David S. Miller Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Al Viro Conflicts: net/ipv4/tcp.c --- diff --git a/fs/dcache.c b/fs/dcache.c index 0b51cfc9291a..9964d6afb128 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -3036,7 +3036,7 @@ __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. @@ -3054,13 +3054,13 @@ 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, @@ -3086,7 +3086,7 @@ 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); } diff --git a/fs/inode.c b/fs/inode.c index 43566d17d1b8..c43f00aae5f5 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -1584,7 +1584,7 @@ __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. @@ -1602,13 +1602,13 @@ 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", @@ -1633,7 +1633,7 @@ 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]); } diff --git a/kernel/pid.c b/kernel/pid.c index 57a8346a270e..cde28eef39f8 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -540,12 +540,12 @@ 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]); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 70c049dc4ee1..1703adcf6b8a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5395,6 +5395,7 @@ 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; diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 6db041d3284c..56c60a38fe79 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3263,7 +3263,7 @@ 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);