coredump: add coredump_write()

to encapsulate that logic simplifying vfs_coredump() even further.

Link: https://lore.kernel.org/20250612-work-coredump-massage-v1-16-315c0c34ba94@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/coredump.c b/fs/coredump.c
index 48d90ec8c86ad579354b2893652f3b82377ad215..dea4823b55b800d8ced1750821d2f07b7dc8ff5c 100644 (file)
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -95,6 +95,7 @@ struct core_name {
        char *corename;
        int used, size;
        unsigned int core_pipe_limit;
+       bool core_dumped;
        enum coredump_type_t core_type;
        u64 mask;
 };
@@ -247,6 +248,7 @@ static bool coredump_parse(struct core_name *cn, struct coredump_params *cprm,
        cn->used = 0;
        cn->corename = NULL;
        cn->core_pipe_limit = 0;
+       cn->core_dumped = false;
        if (*pat_ptr == '|')
                cn->core_type = COREDUMP_PIPE;
        else if (*pat_ptr == '@')
@@ -1037,6 +1039,34 @@ static bool coredump_pipe(struct core_name *cn, struct coredump_params *cprm,
        return true;
 }
 
+static bool coredump_write(struct core_name *cn,
+                         struct coredump_params *cprm,
+                         struct linux_binfmt *binfmt)
+{
+
+       if (dump_interrupted())
+               return true;
+
+       if (!dump_vma_snapshot(cprm))
+               return false;
+
+       file_start_write(cprm->file);
+       cn->core_dumped = binfmt->core_dump(cprm);
+       /*
+        * Ensures that file size is big enough to contain the current
+        * file postion. This prevents gdb from complaining about
+        * a truncated file if the last "write" to the file was
+        * dump_skip.
+        */
+       if (cprm->to_skip) {
+               cprm->to_skip--;
+               dump_emit(cprm, "", 1);
+       }
+       file_end_write(cprm->file);
+       free_vma_snapshot(cprm);
+       return true;
+}
+
 void vfs_coredump(const kernel_siginfo_t *siginfo)
 {
        struct core_state core_state;
@@ -1048,7 +1078,6 @@ void vfs_coredump(const kernel_siginfo_t *siginfo)
        int retval = 0;
        size_t *argv = NULL;
        int argc = 0;
-       bool core_dumped = false;
        struct coredump_params cprm = {
                .siginfo = siginfo,
                .limit = rlimit(RLIMIT_CORE),
@@ -1123,31 +1152,14 @@ void vfs_coredump(const kernel_siginfo_t *siginfo)
        if (retval)
                goto close_fail;
 
-       if ((cn.mask & COREDUMP_KERNEL) && !dump_interrupted()) {
-               if (!dump_vma_snapshot(&cprm))
-                       goto close_fail;
-
-               file_start_write(cprm.file);
-               core_dumped = binfmt->core_dump(&cprm);
-               /*
-                * Ensures that file size is big enough to contain the current
-                * file postion. This prevents gdb from complaining about
-                * a truncated file if the last "write" to the file was
-                * dump_skip.
-                */
-               if (cprm.to_skip) {
-                       cprm.to_skip--;
-                       dump_emit(&cprm, "", 1);
-               }
-               file_end_write(cprm.file);
-               free_vma_snapshot(&cprm);
-       }
+       if ((cn.mask & COREDUMP_KERNEL) && !coredump_write(&cn, &cprm, binfmt))
+               goto close_fail;
 
        coredump_sock_shutdown(cprm.file);
 
        /* Let the parent know that a coredump was generated. */
        if (cn.mask & COREDUMP_USERSPACE)
-               core_dumped = true;
+               cn.core_dumped = true;
 
        /*
         * When core_pipe_limit is set we wait for the coredump server
@@ -1179,7 +1191,7 @@ close_fail:
 fail_unlock:
        kfree(argv);
        kfree(cn.corename);
-       coredump_finish(core_dumped);
+       coredump_finish(cn.core_dumped);
        revert_creds(old_cred);
 fail_creds:
        put_cred(cred);