From: Chengming Zhou <zhouchengming@bytedance.com> stable inclusion from stable-v5.10.209 commit 4518dc468cdd796757190515a9be7408adc8911e category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I99K14 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 744e1885922a9943458954cfea917b31064b4131 ] The req->dst buffer size should be checked before copying from the scomp_scratch->dst to avoid req->dst buffer overflow problem. Fixes: 1ab53a77b772 ("crypto: acomp - add driver-side scomp interface") Reported-by: syzbot+3eff5e51bf1db122a16e@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/0000000000000b05cd060d6b5511@google.com/ Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> Reviewed-by: Barry Song <v-songbaohua@oppo.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Wang Hai <wanghai38@huawei.com> --- crypto/scompress.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/crypto/scompress.c b/crypto/scompress.c index 738f4f8f0f41..4d6366a44400 100644 --- a/crypto/scompress.c +++ b/crypto/scompress.c @@ -124,6 +124,7 @@ static int scomp_acomp_comp_decomp(struct acomp_req *req, int dir) struct crypto_scomp *scomp = *tfm_ctx; void **ctx = acomp_request_ctx(req); struct scomp_scratch *scratch; + unsigned int dlen; int ret; if (!req->src || !req->slen || req->slen > SCOMP_SCRATCH_SIZE) @@ -135,6 +136,8 @@ static int scomp_acomp_comp_decomp(struct acomp_req *req, int dir) if (!req->dlen || req->dlen > SCOMP_SCRATCH_SIZE) req->dlen = SCOMP_SCRATCH_SIZE; + dlen = req->dlen; + scratch = raw_cpu_ptr(&scomp_scratch); spin_lock(&scratch->lock); @@ -152,6 +155,9 @@ static int scomp_acomp_comp_decomp(struct acomp_req *req, int dir) ret = -ENOMEM; goto out; } + } else if (req->dlen > dlen) { + ret = -ENOSPC; + goto out; } scatterwalk_map_and_copy(scratch->dst, req->dst, 0, req->dlen, 1); -- 2.17.1