files-reg: warn when external file has no inherit-fd mapping on restore

CameronBadman · CameronBadman · commit 2d902dd7be08 · 2026-03-18T23:48:24.000+10:00
In open_path(), when inherit_fd_lookup_id() returns negative for an external file, execution silently falls through to the normal open path causing an incorrect size mismatch error. Added a pr_warn() to make the failure explicit. Fixes: #2951 Signed-off-by: Cameron Badman <cbadwork@gmail.com>
diff --git a/criu/files-reg.c b/criu/files-reg.c
@@ -2216,6 +2216,7 @@ int open_path(struct file_desc *d, int (*open_cb)(int mntns_root, struct reg_fil
 			rfi->path = path;
 			goto ext;
 		}
+		pr_warn("External file %s has no --inherit-fd mapping on restore\n", rfi->rfe->name);
 	}
 
 	if (rfi->remap) {

Original file line number	Diff line number	Diff line change
`@@ -2216,6 +2216,7 @@ int open_path(struct file_desc d, int (open_cb)(int mntns_root, struct reg_fil`
`2216`	`2216`	`rfi->path = path;`
`2217`	`2217`	`goto ext;`
`2218`	`2218`	`}`
	`2219`	`+ pr_warn("External file %s has no --inherit-fd mapping on restore\n", rfi->rfe->name);`
`2219`	`2220`	`}`
`2220`	`2221`
`2221`	`2222`	`if (rfi->remap) {`