[PATCH 6.1 412/473] ipv6: sr: fix memleak in seg6_hmac_init_algo

Greg Kroah-Hartman
2024-06-06T14:18:40Z

From: Hangbin Liu <liuhangbin@gmail.com>

[ Upstream commit efb9f4f19f8e37fde43dfecebc80292d179f56c6 ]

seg6_hmac_init_algo returns without cleaning up the previous allocations
if one fails, so it's going to leak all that memory and the crypto tfms.

Update seg6_hmac_exit to only free the memory when allocated, so we can
reuse the code directly.

Fixes: bf355b8d2c30 ("ipv6: sr: add core files for SR HMAC support")
Reported-by: Sabrina Dubroca <sd@queasysnail.net>
Closes: https://lore.kernel.org/netdev/Zj3bh-gE7eT6V6aH@hog/
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://lore.kernel.org/r/20240517005435.2600277-1-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/ipv6/seg6_hmac.c | 42 ++++++++++++++++++++++++++++--------------
1 file changed, 28 insertions(+), 14 deletions(-)

diff --git a/net/ipv6/seg6_hmac.c b/net/ipv6/seg6_hmac.c
index d43c50a7310d6..3c3800223e0e0 100644
--- a/net/ipv6/seg6_hmac.c
+++ b/net/ipv6/seg6_hmac.c
@@ -354,6 +354,7 @@ static int seg6_hmac_init_algo(void)
struct crypto_shash *tfm;
struct shash_desc *shash;
int i, alg_count, cpu;
+ int ret = -ENOMEM;

alg_count = ARRAY_SIZE(hmac_algos);

@@ -364,12 +365,14 @@ static int seg6_hmac_init_algo(void)
algo = &hmac_algos[i];
algo->tfms = alloc_percpu(struct crypto_shash *);
if (!algo->tfms)
- return -ENOMEM;
+ goto error_out;

for_each_possible_cpu(cpu) {
tfm = crypto_alloc_shash(algo->name, 0, 0);
- if (IS_ERR(tfm))
- return PTR_ERR(tfm);
+ if (IS_ERR(tfm)) {
+ ret = PTR_ERR(tfm);
+ goto error_out;
+ }
p_tfm = per_cpu_ptr(algo->tfms, cpu);
*p_tfm = tfm;
}
@@ -381,18 +384,22 @@ static int seg6_hmac_init_algo(void)

algo->shashs = alloc_percpu(struct shash_desc *);
if (!algo->shashs)
- return -ENOMEM;
+ goto error_out;

for_each_possible_cpu(cpu) {
shash = kzalloc_node(shsize, GFP_KERNEL,
cpu_to_node(cpu));
if (!shash)
- return -ENOMEM;
+ goto error_out;
*per_cpu_ptr(algo->shashs, cpu) = shash;
}
}

return 0;
+
+error_out:
+ seg6_hmac_exit();
+ return ret;
}

int __init seg6_hmac_init(void)
@@ -410,22 +417,29 @@ int __net_init seg6_hmac_net_init(struct net *net)
void seg6_hmac_exit(void)
{
struct seg6_hmac_algo *algo = NULL;
+ struct crypto_shash *tfm;
+ struct shash_desc *shash;
int i, alg_count, cpu;

alg_count = ARRAY_SIZE(hmac_algos);
for (i = 0; i < alg_count; i++) {
algo = &hmac_algos[i];
- for_each_possible_cpu(cpu) {
- struct crypto_shash *tfm;
- struct shash_desc *shash;

- shash = *per_cpu_ptr(algo->shashs, cpu);
- kfree(shash);
- tfm = *per_cpu_ptr(algo->tfms, cpu);
- crypto_free_shash(tfm);
+ if (algo->shashs) {
+ for_each_possible_cpu(cpu) {
+ shash = *per_cpu_ptr(algo->shashs, cpu);
+ kfree(shash);
+ }
+ free_percpu(algo->shashs);
+ }
+
+ if (algo->tfms) {
+ for_each_possible_cpu(cpu) {
+ tfm = *per_cpu_ptr(algo->tfms, cpu);
+ crypto_free_shash(tfm);
+ }
+ free_percpu(algo->tfms);
}
- free_percpu(algo->tfms);
- free_percpu(algo->shashs);
}
}
EXPORT_SYMBOL(seg6_hmac_exit);
--
2.43.0