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author | 2016-09-07 20:18:02 +0530 | |
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committer | 2016-09-13 20:27:22 +0800 | |
commit | 58b022acac8dd435dad0b162ad92cbe8ec90a703 (patch) | |
tree | 09dd4e1bf5d30a103e9eaa905cae7b6fe3631291 /drivers/char | |
parent | crypto: qat - fix leak on error path (diff) | |
download | linux-58b022acac8dd435dad0b162ad92cbe8ec90a703.tar.gz linux-58b022acac8dd435dad0b162ad92cbe8ec90a703.tar.bz2 linux-58b022acac8dd435dad0b162ad92cbe8ec90a703.zip |
hwrng: core - Allocate memory during module init
In core rng_buffer and rng_fillbuf is allocated in hwrng_register only
once and it is freed during module exit. This patch moves allocating
rng_buffer and rng_fillbuf from hwrng_register to rng core's init. This
avoids checking whether rng_buffer and rng_fillbuf was allocated from
every hwrng_register call. Also moving them to module init makes it
explicit that it is freed in module exit.
Change in v2:
Fix memory leak when register_miscdev fails.
Signed-off-by: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/char')
-rw-r--r-- | drivers/char/hw_random/core.c | 37 |
1 files changed, 20 insertions, 17 deletions
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index 9203f2d130c0..482794526e8c 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -449,22 +449,6 @@ int hwrng_register(struct hwrng *rng) goto out; mutex_lock(&rng_mutex); - - /* kmalloc makes this safe for virt_to_page() in virtio_rng.c */ - err = -ENOMEM; - if (!rng_buffer) { - rng_buffer = kmalloc(rng_buffer_size(), GFP_KERNEL); - if (!rng_buffer) - goto out_unlock; - } - if (!rng_fillbuf) { - rng_fillbuf = kmalloc(rng_buffer_size(), GFP_KERNEL); - if (!rng_fillbuf) { - kfree(rng_buffer); - goto out_unlock; - } - } - /* Must not register two RNGs with the same name. */ err = -EEXIST; list_for_each_entry(tmp, &rng_list, list) { @@ -573,7 +557,26 @@ EXPORT_SYMBOL_GPL(devm_hwrng_unregister); static int __init hwrng_modinit(void) { - return register_miscdev(); + int ret = -ENOMEM; + + /* kmalloc makes this safe for virt_to_page() in virtio_rng.c */ + rng_buffer = kmalloc(rng_buffer_size(), GFP_KERNEL); + if (!rng_buffer) + return -ENOMEM; + + rng_fillbuf = kmalloc(rng_buffer_size(), GFP_KERNEL); + if (!rng_fillbuf) { + kfree(rng_buffer); + return -ENOMEM; + } + + ret = register_miscdev(); + if (ret) { + kfree(rng_fillbuf); + kfree(rng_buffer); + } + + return ret; } static void __exit hwrng_modexit(void) |