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smb: client: reduce stack usage in cifs_try_adding_channels()

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Clang warns about exceeded stack frame size

  fs/smb/client/sess.c:160:5: warning: stack frame size (1368) exceeds
  limit (1024) in 'cifs_try_adding_channels' [-Wframe-larger-than]

It turns out that cifs_ses_add_channel() got inlined into
cifs_try_adding_channels() which had a stack-allocated variable @ctx
of 624 bytes in size.  Fix this by making it heap-allocated.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202307270640.5ODmPwDl-lkp@intel.com/
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Paulo Alcantara 2023-08-17 12:34:10 -03:00 committed by Steve French
parent a18280e7fd
commit 69a4e06c0e
1 changed files with 41 additions and 27 deletions
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68
fs/smb/client/sess.c
View File

@ -360,11 +360,11 @@ cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
{
struct TCP_Server_Info *chan_server;
struct cifs_chan *chan;
struct smb3_fs_context ctx = {NULL};
struct smb3_fs_context *ctx;
static const char unc_fmt[] = "\\%s\\foo";
char unc[sizeof(unc_fmt)+SERVER_NAME_LEN_WITH_NULL] = {0};
struct sockaddr_in *ipv4 = (struct sockaddr_in *)&iface->sockaddr;
struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&iface->sockaddr;
size_t len;
int rc;
unsigned int xid = get_xid();
@ -388,54 +388,64 @@ cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
* the session and server without caring about memory
* management.
*/
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx) {
rc = -ENOMEM;
goto out_free_xid;
}
/* Always make new connection for now (TODO?) */
ctx.nosharesock = true;
ctx->nosharesock = true;
/* Auth */
ctx.domainauto = ses->domainAuto;
ctx.domainname = ses->domainName;
ctx->domainauto = ses->domainAuto;
ctx->domainname = ses->domainName;
/* no hostname for extra channels */
ctx.server_hostname = "";
ctx->server_hostname = "";
ctx.username = ses->user_name;
ctx.password = ses->password;
ctx.sectype = ses->sectype;
ctx.sign = ses->sign;
ctx->username = ses->user_name;
ctx->password = ses->password;
ctx->sectype = ses->sectype;
ctx->sign = ses->sign;
/* UNC and paths */
/* XXX: Use ses->server->hostname? */
sprintf(unc, unc_fmt, ses->ip_addr);
ctx.UNC = unc;
ctx.prepath = "";
len = sizeof(unc_fmt) + SERVER_NAME_LEN_WITH_NULL;
ctx->UNC = kzalloc(len, GFP_KERNEL);
if (!ctx->UNC) {
rc = -ENOMEM;
goto out_free_ctx;
}
scnprintf(ctx->UNC, len, unc_fmt, ses->ip_addr);
ctx->prepath = "";
/* Reuse same version as master connection */
ctx.vals = ses->server->vals;
ctx.ops = ses->server->ops;
ctx->vals = ses->server->vals;
ctx->ops = ses->server->ops;
ctx.noblocksnd = ses->server->noblocksnd;
ctx.noautotune = ses->server->noautotune;
ctx.sockopt_tcp_nodelay = ses->server->tcp_nodelay;
ctx.echo_interval = ses->server->echo_interval / HZ;
ctx.max_credits = ses->server->max_credits;
ctx->noblocksnd = ses->server->noblocksnd;
ctx->noautotune = ses->server->noautotune;
ctx->sockopt_tcp_nodelay = ses->server->tcp_nodelay;
ctx->echo_interval = ses->server->echo_interval / HZ;
ctx->max_credits = ses->server->max_credits;
/*
* This will be used for encoding/decoding user/domain/pw
* during sess setup auth.
*/
ctx.local_nls = cifs_sb->local_nls;
ctx->local_nls = cifs_sb->local_nls;
/* Use RDMA if possible */
ctx.rdma = iface->rdma_capable;
memcpy(&ctx.dstaddr, &iface->sockaddr, sizeof(struct sockaddr_storage));
ctx->rdma = iface->rdma_capable;
memcpy(&ctx->dstaddr, &iface->sockaddr, sizeof(ctx->dstaddr));
/* reuse master con client guid */
memcpy(&ctx.client_guid, ses->server->client_guid,
SMB2_CLIENT_GUID_SIZE);
ctx.use_client_guid = true;
memcpy(&ctx->client_guid, ses->server->client_guid,
sizeof(ctx->client_guid));
ctx->use_client_guid = true;
chan_server = cifs_get_tcp_session(&ctx, ses->server);
chan_server = cifs_get_tcp_session(ctx, ses->server);
spin_lock(&ses->chan_lock);
chan = &ses->chans[ses->chan_count];
@ -497,6 +507,10 @@ out:
cifs_put_tcp_session(chan->server, 0);
}
kfree(ctx->UNC);
out_free_ctx:
kfree(ctx);
out_free_xid:
free_xid(xid);
return rc;
}