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| author | Hawkins Jiawei <yin31149@gmail.com> | 2022-10-23 19:39:45 +0300 |
|---|---|---|
| committer | Trond Myklebust <trond.myklebust@hammerspace.com> | 2022-12-06 18:43:24 +0300 |
| commit | 5559405df652008e56eee88872126fe4c451da67 (patch) | |
| tree | 06482691076b88a6726698c286192d218351d307 /fs/nfs | |
| parent | d564d2c4c2445cb0972453933dc87c2dcaac8597 (diff) | |
| download | linux-5559405df652008e56eee88872126fe4c451da67.tar.xz | |
nfs: fix possible null-ptr-deref when parsing param
According to commit "vfs: parse: deal with zero length string value",
kernel will set the param->string to null pointer in vfs_parse_fs_string()
if fs string has zero length.
Yet the problem is that, nfs_fs_context_parse_param() will dereferences the
param->string, without checking whether it is a null pointer, which may
trigger a null-ptr-deref bug.
This patch solves it by adding sanity check on param->string
in nfs_fs_context_parse_param().
Signed-off-by: Hawkins Jiawei <yin31149@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Diffstat (limited to 'fs/nfs')
| -rw-r--r-- | fs/nfs/fs_context.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c index 09833ec102fc..9bcd53d5c7d4 100644 --- a/fs/nfs/fs_context.c +++ b/fs/nfs/fs_context.c @@ -684,6 +684,8 @@ static int nfs_fs_context_parse_param(struct fs_context *fc, return ret; break; case Opt_vers: + if (!param->string) + goto out_invalid_value; trace_nfs_mount_assign(param->key, param->string); ret = nfs_parse_version_string(fc, param->string); if (ret < 0) @@ -696,6 +698,8 @@ static int nfs_fs_context_parse_param(struct fs_context *fc, break; case Opt_proto: + if (!param->string) + goto out_invalid_value; trace_nfs_mount_assign(param->key, param->string); protofamily = AF_INET; switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) { @@ -732,6 +736,8 @@ static int nfs_fs_context_parse_param(struct fs_context *fc, break; case Opt_mountproto: + if (!param->string) + goto out_invalid_value; trace_nfs_mount_assign(param->key, param->string); mountfamily = AF_INET; switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) { |