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| author | Guangguan Wang <guangguan.wang@linux.alibaba.com> | 2024-12-11 12:21:20 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-27 15:52:54 +0300 |
| commit | e1cc8be2a785a8f1ce1f597f3e608602c5fccd46 (patch) | |
| tree | 0a2b09ed8387e6393106adcb0f6c21f1a833fc44 | |
| parent | 62056d1592e63d85e82357ee2ae6a6a294f440b0 (diff) | |
| download | linux-e1cc8be2a785a8f1ce1f597f3e608602c5fccd46.tar.xz | |
net/smc: check smcd_v2_ext_offset when receiving proposal msg
[ Upstream commit 9ab332deb671d8f7e66d82a2ff2b3f715bc3a4ad ]
When receiving proposal msg in server, the field smcd_v2_ext_offset in
proposal msg is from the remote client and can not be fully trusted.
Once the value of smcd_v2_ext_offset exceed the max value, there has
the chance to access wrong address, and crash may happen.
This patch checks the value of smcd_v2_ext_offset before using it.
Fixes: 5c21c4ccafe8 ("net/smc: determine accepted ISM devices")
Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
Reviewed-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-by: D. Wythe <alibuda@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/smc/af_smc.c | 2 | ||||
| -rw-r--r-- | net/smc/smc_clc.h | 8 |
2 files changed, 9 insertions, 1 deletions
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 889709c35b1f..e2bdd6aa3d89 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -2096,6 +2096,8 @@ static void smc_find_ism_v2_device_serv(struct smc_sock *new_smc, pclc_smcd = smc_get_clc_msg_smcd(pclc); smc_v2_ext = smc_get_clc_v2_ext(pclc); smcd_v2_ext = smc_get_clc_smcd_v2_ext(smc_v2_ext); + if (!pclc_smcd || !smc_v2_ext || !smcd_v2_ext) + goto not_found; mutex_lock(&smcd_dev_list.mutex); if (pclc_smcd->ism.chid) diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h index 08279081d438..0f6102cd5de1 100644 --- a/net/smc/smc_clc.h +++ b/net/smc/smc_clc.h @@ -361,9 +361,15 @@ smc_get_clc_v2_ext(struct smc_clc_msg_proposal *prop) static inline struct smc_clc_smcd_v2_extension * smc_get_clc_smcd_v2_ext(struct smc_clc_v2_extension *prop_v2ext) { + u16 max_offset = offsetof(struct smc_clc_msg_proposal_area, pclc_smcd_v2_ext) - + offsetof(struct smc_clc_msg_proposal_area, pclc_v2_ext) - + offsetof(struct smc_clc_v2_extension, hdr) - + offsetofend(struct smc_clnt_opts_area_hdr, smcd_v2_ext_offset); + if (!prop_v2ext) return NULL; - if (!ntohs(prop_v2ext->hdr.smcd_v2_ext_offset)) + if (!ntohs(prop_v2ext->hdr.smcd_v2_ext_offset) || + ntohs(prop_v2ext->hdr.smcd_v2_ext_offset) > max_offset) return NULL; return (struct smc_clc_smcd_v2_extension *) |