samsung_sm8750/android_kernel_samsung_sm8750
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

UPSTREAM: af_unix: Allocate struct unix_edge for each inflight AF_UNIX fd.

Browse Source 
commit 29b64e354029cfcf1eea4d91b146c7b769305930 upstream.

As with the previous patch, we preallocate to skb's scm_fp_list an
array of struct unix_edge in the number of inflight AF_UNIX fds.

There we just preallocate memory and do not use immediately because
sendmsg() could fail after this point.  The actual use will be in
the next patch.

When we queue skb with inflight edges, we will set the inflight
socket's unix_sock as unix_edge->predecessor and the receiver's
unix_sock as successor, and then we will link the edge to the
inflight socket's unix_vertex.edges.

Note that we set NULL to cloned scm_fp_list.edges in scm_fp_dup()
so that MSG_PEEK does not change the shape of the directed graph.

Bug: 404256079
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240325202425.60930-3-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 4fc7df1c6d)
Signed-off-by: Lee Jones <joneslee@google.com>
Change-Id: I9b0d639f1ac8fb3b9c032aebcca6d5bb59e3fc79
This commit is contained in:
Kuniyuki Iwashima
2025-05-21 14:45:16 +00:00
committed by Lee Jones
parent c93b3ba51e
commit 844c9666eb
4 changed files with 21 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
include/net/af_unix.h
View File

@@ -33,6 +33,12 @@ struct unix_vertex {
unsigned long out_degree;
};
struct unix_edge {
struct unix_sock *predecessor;
struct unix_sock *successor;
struct list_head vertex_entry;
};
struct sock *unix_peer_get(struct sock *sk);
#define UNIX_HASH_MOD (256 - 1)

7
include/net/scm.h
View File

@@ -22,9 +22,16 @@ struct scm_creds {
kgid_t gid;
};
#ifdef CONFIG_UNIX
struct unix_edge;
#endif
struct scm_fp_list {
short count;
short max;
#ifdef CONFIG_UNIX
struct unix_edge *edges;
#endif
struct user_struct *user;
struct file *fp[SCM_MAX_FD];
#ifndef __GENKSYMS__

2
net/core/scm.c
View File

@@ -90,6 +90,7 @@ static int scm_fp_copy(struct cmsghdr *cmsg, struct scm_fp_list **fplp)
fpl->max = SCM_MAX_FD;
fpl->user = NULL;
#if IS_ENABLED(CONFIG_UNIX)
fpl->edges = NULL;
INIT_LIST_HEAD(&fpl->vertices);
#endif
}
@@ -382,6 +383,7 @@ struct scm_fp_list *scm_fp_dup(struct scm_fp_list *fpl)
new_fpl->max = new_fpl->count;
new_fpl->user = get_uid(fpl->user);
#if IS_ENABLED(CONFIG_UNIX)
new_fpl->edges = NULL;
INIT_LIST_HEAD(&new_fpl->vertices);
#endif
}

6
net/unix/garbage.c
View File

@@ -127,6 +127,11 @@ int unix_prepare_fpl(struct scm_fp_list *fpl)
list_add(&vertex->entry, &fpl->vertices);
}
fpl->edges = kvmalloc_array(fpl->count_unix, sizeof(*fpl->edges),
GFP_KERNEL_ACCOUNT);
if (!fpl->edges)
goto err;
return 0;
err:
@@ -136,6 +141,7 @@ err:
void unix_destroy_fpl(struct scm_fp_list *fpl)
{
kvfree(fpl->edges);
unix_free_vertices(fpl);
}