| Message ID | 20250418100229.9868-1-dmantipov@yandex.ru |
|---|---|
| State | New |
| Headers | show |
| Series | crypto: acomp: fix memory leaks caused by chained requests | expand |
On Fri, Apr 18, 2025 at 01:02:29PM +0300, Dmitry Antipov wrote: > Running 6.15.0-rc2 with kmemleak enabled, I've noticed 45 > memory leaks looks like the following: > > unreferenced object 0xffff888114032a00 (size 256): > comm "cryptomgr_test", pid 246, jiffies 4294668840 > hex dump (first 32 bytes): > 00 20 03 14 81 88 ff ff 00 da 02 14 81 88 ff ff . .............. > 90 ca 54 9b ff ff ff ff c8 fb a6 00 00 c9 ff ff ..T............. > backtrace (crc cd58738d): > __kmalloc_noprof+0x272/0x520 > alg_test_comp+0x74e/0x1b60 > alg_test+0x3f0/0xc40 > cryptomgr_test+0x47/0x80 > kthread+0x4e1/0x620 > ret_from_fork+0x37/0x70 > ret_from_fork_asm+0x1a/0x30 > > These leaks comes from 'test_acomp()' where an extra requests chained to > the head one (e.g. 'reqs[0]') are never freed. Fix this by unchaining > and freeing such an extra requests in 'acomp_request_free()'. > > (I'm new to this subsystem and not sure about Fixes: tag BTW). > > Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> > --- > include/crypto/acompress.h | 28 ++++++++++++++++++++++------ > include/linux/crypto.h | 5 +++++ > 2 files changed, 27 insertions(+), 6 deletions(-) Thanks for the patch! I'll fix this by reverting the multibuffer acomp tests: https://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6.git/commit/?id=aece1cf146741761a1243746db5b72f5ece68290
diff --git a/include/crypto/acompress.h b/include/crypto/acompress.h index c497c73baf13..d7de4cbccd60 100644 --- a/include/crypto/acompress.h +++ b/include/crypto/acompress.h @@ -310,6 +310,20 @@ static inline void *acomp_request_extra(struct acomp_req *req) return (void *)((char *)req + len); } +static inline void acomp_request_chain(struct acomp_req *req, + struct acomp_req *head) +{ + crypto_request_chain(&req->base, &head->base); +} + +static inline void acomp_request_unchain(struct acomp_req *req) +{ + crypto_request_unchain(&req->base); +} + +#define acomp_request_for_each(this, tmp, head) \ + list_for_each_entry_safe((this), (tmp), &(head)->base.list, base.list) + /** * acomp_request_free() -- zeroize and free asynchronous (de)compression * request as well as the output buffer if allocated @@ -319,8 +333,16 @@ static inline void *acomp_request_extra(struct acomp_req *req) */ static inline void acomp_request_free(struct acomp_req *req) { + struct acomp_req *this, *tmp; + if (!req || (req->base.flags & CRYPTO_TFM_REQ_ON_STACK)) return; + + acomp_request_for_each(this, tmp, req) { + acomp_request_unchain(this); + kfree_sensitive(this); + } + kfree_sensitive(req); } @@ -558,12 +580,6 @@ static inline void acomp_request_set_dst_folio(struct acomp_req *req, req->base.flags |= CRYPTO_ACOMP_REQ_DST_FOLIO; } -static inline void acomp_request_chain(struct acomp_req *req, - struct acomp_req *head) -{ - crypto_request_chain(&req->base, &head->base); -} - /** * crypto_acomp_compress() -- Invoke asynchronous compress operation * diff --git a/include/linux/crypto.h b/include/linux/crypto.h index 1e3809d28abd..3e12bcee1497 100644 --- a/include/linux/crypto.h +++ b/include/linux/crypto.h @@ -486,6 +486,11 @@ static inline void crypto_request_chain(struct crypto_async_request *req, list_add_tail(&req->list, &head->list); } +static inline void crypto_request_unchain(struct crypto_async_request *req) +{ + list_del(&req->list); +} + static inline bool crypto_tfm_is_async(struct crypto_tfm *tfm) { return tfm->__crt_alg->cra_flags & CRYPTO_ALG_ASYNC;
Running 6.15.0-rc2 with kmemleak enabled, I've noticed 45 memory leaks looks like the following: unreferenced object 0xffff888114032a00 (size 256): comm "cryptomgr_test", pid 246, jiffies 4294668840 hex dump (first 32 bytes): 00 20 03 14 81 88 ff ff 00 da 02 14 81 88 ff ff . .............. 90 ca 54 9b ff ff ff ff c8 fb a6 00 00 c9 ff ff ..T............. backtrace (crc cd58738d): __kmalloc_noprof+0x272/0x520 alg_test_comp+0x74e/0x1b60 alg_test+0x3f0/0xc40 cryptomgr_test+0x47/0x80 kthread+0x4e1/0x620 ret_from_fork+0x37/0x70 ret_from_fork_asm+0x1a/0x30 These leaks comes from 'test_acomp()' where an extra requests chained to the head one (e.g. 'reqs[0]') are never freed. Fix this by unchaining and freeing such an extra requests in 'acomp_request_free()'. (I'm new to this subsystem and not sure about Fixes: tag BTW). Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> --- include/crypto/acompress.h | 28 ++++++++++++++++++++++------ include/linux/crypto.h | 5 +++++ 2 files changed, 27 insertions(+), 6 deletions(-)