From 474a89885f77953b12bce9f23660c31ef5c2630e Mon Sep 17 00:00:00 2001 From: Jesper Juhl Date: Wed, 11 Apr 2012 22:10:20 +0200 Subject: [PATCH] staging: android: fix mem leaks in __persistent_ram_init() If, in __persistent_ram_init(), the call to persistent_ram_buffer_init() fails or the call to persistent_ram_init_ecc() fails then we fail to free the memory we allocated to 'prz' with kzalloc() - thus leaking it. To prevent the leaks I consolidated all error exits from the function at a 'err:' label at the end and made all error cases jump to that label where we can then make sure we always free 'prz'. This is safe since all the situations where the code bails out happen before 'prz' has been stored anywhere and although we'll do a redundant kfree(NULL) call in the case of kzalloc() itself failing that's OK since kfree() deals gracefully with NULL pointers and I felt it was more important to keep all error exits at a single location than to avoid that one harmless/redundant kfree() on a error path. Signed-off-by: Jesper Juhl Acked-by: Colin Cross Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/staging/android/persistent_ram.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/staging/android/persistent_ram.c b/drivers/staging/android/persistent_ram.c index e08f2574e30a..8d8c1e33e0ff 100644 --- a/drivers/staging/android/persistent_ram.c +++ b/drivers/staging/android/persistent_ram.c @@ -399,12 +399,12 @@ static __init struct persistent_ram_zone *__persistent_ram_init(struct device *dev, bool ecc) { struct persistent_ram_zone *prz; - int ret; + int ret = -ENOMEM; prz = kzalloc(sizeof(struct persistent_ram_zone), GFP_KERNEL); if (!prz) { pr_err("persistent_ram: failed to allocate persistent ram zone\n"); - return ERR_PTR(-ENOMEM); + goto err; } INIT_LIST_HEAD(&prz->node); @@ -412,13 +412,13 @@ struct persistent_ram_zone *__persistent_ram_init(struct device *dev, bool ecc) ret = persistent_ram_buffer_init(dev_name(dev), prz); if (ret) { pr_err("persistent_ram: failed to initialize buffer\n"); - return ERR_PTR(ret); + goto err; } prz->ecc = ecc; ret = persistent_ram_init_ecc(prz, prz->buffer_size); if (ret) - return ERR_PTR(ret); + goto err; if (prz->buffer->sig == PERSISTENT_RAM_SIG) { if (buffer_size(prz) > prz->buffer_size || @@ -442,6 +442,9 @@ struct persistent_ram_zone *__persistent_ram_init(struct device *dev, bool ecc) atomic_set(&prz->buffer->size, 0); return prz; +err: + kfree(prz); + return ERR_PTR(ret); } struct persistent_ram_zone * __init