We use chmod(3P) to modify permissions of "tables.list" locks as well as
temporary new tables we're writing. In all of these cases we do have a
file descriptor readily available though. So instead of using chmod(3P)
we can use fchmod(3P), which should both be more efficient while also
avoiding a potential race where we change permissions of the wrong file
in case it was swapped out after we have created it.
Refactor the code to do so.
Signed-off-by: Patrick Steinhardt <ps@xxxxxx>
---
reftable/stack.c | 29 ++++++++++++++---------------
1 file changed, 14 insertions(+), 15 deletions(-)
diff --git a/reftable/stack.c b/reftable/stack.c
index 7ffeb3ee10..c6e4dc4b2b 100644
--- a/reftable/stack.c
+++ b/reftable/stack.c
@@ -467,11 +467,11 @@ static int reftable_stack_init_addition(struct reftable_addition *add,
}
goto done;
}
- if (st->config.default_permissions) {
- if (chmod(add->lock_file->filename.buf, st->config.default_permissions) < 0) {
- err = REFTABLE_IO_ERROR;
- goto done;
- }
+ if (st->config.default_permissions &&
+ fchmod(get_tempfile_fd(add->lock_file),
+ st->config.default_permissions) < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
}
err = stack_uptodate(st);
@@ -633,12 +633,12 @@ int reftable_addition_add(struct reftable_addition *add,
err = REFTABLE_IO_ERROR;
goto done;
}
- if (add->stack->config.default_permissions) {
- if (chmod(temp_tab_file_name.buf, add->stack->config.default_permissions)) {
- err = REFTABLE_IO_ERROR;
- goto done;
- }
+ if (add->stack->config.default_permissions &&
+ fchmod(tab_fd, add->stack->config.default_permissions) < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
}
+
wr = reftable_new_writer(reftable_fd_write, &tab_fd,
&add->stack->config);
err = write_table(wr, arg);
@@ -967,11 +967,10 @@ static int stack_compact_range(struct reftable_stack *st, int first, int last,
goto done;
}
have_lock = 1;
- if (st->config.default_permissions) {
- if (chmod(lock_file_name.buf, st->config.default_permissions) < 0) {
- err = REFTABLE_IO_ERROR;
- goto done;
- }
+ if (st->config.default_permissions &&
+ fchmod(lock_file_fd, st->config.default_permissions) < 0) {
+ err = REFTABLE_IO_ERROR;
+ goto done;
}
format_name(&new_table_name, st->readers[first]->min_update_index,
--
2.43.GIT
Attachment:
signature.asc
Description: PGP signature
