The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 0d52154bb0a700abb459a2cbce0a30fc2549b67e Mon Sep 17 00:00:00 2001
From: Chengguang Xu cgxu519@gmail.com Date: Fri, 10 May 2019 21:15:47 -0400 Subject: [PATCH] jbd2: fix potential double free
When failing from creating cache jbd2_inode_cache, we will destroy the previously created cache jbd2_handle_cache twice. This patch fixes this by moving each cache initialization/destruction to its own separate, individual function.
Signed-off-by: Chengguang Xu cgxu519@gmail.com Signed-off-by: Theodore Ts'o tytso@mit.edu Cc: stable@kernel.org
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index 37e16d969925..43df0c943229 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -2375,22 +2375,19 @@ static struct kmem_cache *jbd2_journal_head_cache; static atomic_t nr_journal_heads = ATOMIC_INIT(0); #endif
-static int jbd2_journal_init_journal_head_cache(void) +static int __init jbd2_journal_init_journal_head_cache(void) { - int retval; - - J_ASSERT(jbd2_journal_head_cache == NULL); + J_ASSERT(!jbd2_journal_head_cache); jbd2_journal_head_cache = kmem_cache_create("jbd2_journal_head", sizeof(struct journal_head), 0, /* offset */ SLAB_TEMPORARY | SLAB_TYPESAFE_BY_RCU, NULL); /* ctor */ - retval = 0; if (!jbd2_journal_head_cache) { - retval = -ENOMEM; printk(KERN_EMERG "JBD2: no memory for journal_head cache\n"); + return -ENOMEM; } - return retval; + return 0; }
static void jbd2_journal_destroy_journal_head_cache(void) @@ -2636,28 +2633,38 @@ static void __exit jbd2_remove_jbd_stats_proc_entry(void)
struct kmem_cache *jbd2_handle_cache, *jbd2_inode_cache;
+static int __init jbd2_journal_init_inode_cache(void) +{ + J_ASSERT(!jbd2_inode_cache); + jbd2_inode_cache = KMEM_CACHE(jbd2_inode, 0); + if (!jbd2_inode_cache) { + pr_emerg("JBD2: failed to create inode cache\n"); + return -ENOMEM; + } + return 0; +} + static int __init jbd2_journal_init_handle_cache(void) { + J_ASSERT(!jbd2_handle_cache); jbd2_handle_cache = KMEM_CACHE(jbd2_journal_handle, SLAB_TEMPORARY); - if (jbd2_handle_cache == NULL) { + if (!jbd2_handle_cache) { printk(KERN_EMERG "JBD2: failed to create handle cache\n"); return -ENOMEM; } - jbd2_inode_cache = KMEM_CACHE(jbd2_inode, 0); - if (jbd2_inode_cache == NULL) { - printk(KERN_EMERG "JBD2: failed to create inode cache\n"); - kmem_cache_destroy(jbd2_handle_cache); - return -ENOMEM; - } return 0; }
+static void jbd2_journal_destroy_inode_cache(void) +{ + kmem_cache_destroy(jbd2_inode_cache); + jbd2_inode_cache = NULL; +} + static void jbd2_journal_destroy_handle_cache(void) { kmem_cache_destroy(jbd2_handle_cache); jbd2_handle_cache = NULL; - kmem_cache_destroy(jbd2_inode_cache); - jbd2_inode_cache = NULL; }
/* @@ -2668,11 +2675,15 @@ static int __init journal_init_caches(void) { int ret;
- ret = jbd2_journal_init_revoke_caches(); + ret = jbd2_journal_init_revoke_record_cache(); + if (ret == 0) + ret = jbd2_journal_init_revoke_table_cache(); if (ret == 0) ret = jbd2_journal_init_journal_head_cache(); if (ret == 0) ret = jbd2_journal_init_handle_cache(); + if (ret == 0) + ret = jbd2_journal_init_inode_cache(); if (ret == 0) ret = jbd2_journal_init_transaction_cache(); return ret; @@ -2680,9 +2691,11 @@ static int __init journal_init_caches(void)
static void jbd2_journal_destroy_caches(void) { - jbd2_journal_destroy_revoke_caches(); + jbd2_journal_destroy_revoke_record_cache(); + jbd2_journal_destroy_revoke_table_cache(); jbd2_journal_destroy_journal_head_cache(); jbd2_journal_destroy_handle_cache(); + jbd2_journal_destroy_inode_cache(); jbd2_journal_destroy_transaction_cache(); jbd2_journal_destroy_slabs(); } diff --git a/fs/jbd2/revoke.c b/fs/jbd2/revoke.c index a1143e57a718..69b9bc329964 100644 --- a/fs/jbd2/revoke.c +++ b/fs/jbd2/revoke.c @@ -178,33 +178,41 @@ static struct jbd2_revoke_record_s *find_revoke_record(journal_t *journal, return NULL; }
-void jbd2_journal_destroy_revoke_caches(void) +void jbd2_journal_destroy_revoke_record_cache(void) { kmem_cache_destroy(jbd2_revoke_record_cache); jbd2_revoke_record_cache = NULL; +} + +void jbd2_journal_destroy_revoke_table_cache(void) +{ kmem_cache_destroy(jbd2_revoke_table_cache); jbd2_revoke_table_cache = NULL; }
-int __init jbd2_journal_init_revoke_caches(void) +int __init jbd2_journal_init_revoke_record_cache(void) { J_ASSERT(!jbd2_revoke_record_cache); - J_ASSERT(!jbd2_revoke_table_cache); - jbd2_revoke_record_cache = KMEM_CACHE(jbd2_revoke_record_s, SLAB_HWCACHE_ALIGN|SLAB_TEMPORARY); - if (!jbd2_revoke_record_cache) - goto record_cache_failure;
+ if (!jbd2_revoke_record_cache) { + pr_emerg("JBD2: failed to create revoke_record cache\n"); + return -ENOMEM; + } + return 0; +} + +int __init jbd2_journal_init_revoke_table_cache(void) +{ + J_ASSERT(!jbd2_revoke_table_cache); jbd2_revoke_table_cache = KMEM_CACHE(jbd2_revoke_table_s, SLAB_TEMPORARY); - if (!jbd2_revoke_table_cache) - goto table_cache_failure; - return 0; -table_cache_failure: - jbd2_journal_destroy_revoke_caches(); -record_cache_failure: + if (!jbd2_revoke_table_cache) { + pr_emerg("JBD2: failed to create revoke_table cache\n"); return -ENOMEM; + } + return 0; }
static struct jbd2_revoke_table_s *jbd2_journal_init_revoke_table(int hash_size) diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index f940d31c2adc..8ca4fddc705f 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -42,9 +42,11 @@ int __init jbd2_journal_init_transaction_cache(void) 0, SLAB_HWCACHE_ALIGN|SLAB_TEMPORARY, NULL); - if (transaction_cache) - return 0; - return -ENOMEM; + if (!transaction_cache) { + pr_emerg("JBD2: failed to create transaction cache\n"); + return -ENOMEM; + } + return 0; }
void jbd2_journal_destroy_transaction_cache(void) diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h index 0f919d5fe84f..2cf6e04b08fc 100644 --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -1318,7 +1318,7 @@ extern void __wait_on_journal (journal_t *);
/* Transaction cache support */ extern void jbd2_journal_destroy_transaction_cache(void); -extern int jbd2_journal_init_transaction_cache(void); +extern int __init jbd2_journal_init_transaction_cache(void); extern void jbd2_journal_free_transaction(transaction_t *);
/* @@ -1446,8 +1446,10 @@ static inline void jbd2_free_inode(struct jbd2_inode *jinode) /* Primary revoke support */ #define JOURNAL_REVOKE_DEFAULT_HASH 256 extern int jbd2_journal_init_revoke(journal_t *, int); -extern void jbd2_journal_destroy_revoke_caches(void); -extern int jbd2_journal_init_revoke_caches(void); +extern void jbd2_journal_destroy_revoke_record_cache(void); +extern void jbd2_journal_destroy_revoke_table_cache(void); +extern int __init jbd2_journal_init_revoke_record_cache(void); +extern int __init jbd2_journal_init_revoke_table_cache(void);
extern void jbd2_journal_destroy_revoke(journal_t *); extern int jbd2_journal_revoke (handle_t *, unsigned long long, struct buffer_head *);