Introduce a fsck check for the reftable backend, which checks if the
'tables.list' contains a newline. The reftable backend writes a trailing
newline when writing the 'tables.list', but it doesn't check for it when
reading the file. A missing newline however indicates that the file was
manually tampered with, so let's raise this as an error to the user.
Signed-off-by: Karthik Nayak <karthik.188@xxxxxxxxx>
---
Documentation/fsck-msgids.adoc | 3 +++
fsck.h | 1 +
refs/reftable-backend.c | 3 +++
reftable/fsck.c | 36 ++++++++++++++++++++++++++++++++++++
reftable/reftable-fsck.h | 2 ++
t/t0614-reftable-fsck.sh | 21 +++++++++++++++++++++
6 files changed, 66 insertions(+)
diff --git a/Documentation/fsck-msgids.adoc b/Documentation/fsck-msgids.adoc
index 707e2fc50a..1432b1de06 100644
--- a/Documentation/fsck-msgids.adoc
+++ b/Documentation/fsck-msgids.adoc
@@ -41,6 +41,9 @@
`badReftableStackCount`::
(ERROR) Mismatch in number of tables.
+`badReftableStackListNewline`::
+ (ERROR) Reftable stack list missing trailing newline.
+
`badReftableTableName`::
(ERROR) A reftable table has an invalid name.
diff --git a/fsck.h b/fsck.h
index 256effc4f8..33432bae79 100644
--- a/fsck.h
+++ b/fsck.h
@@ -35,6 +35,7 @@ enum fsck_msg_type {
FUNC(BAD_PARENT_SHA1, ERROR) \
FUNC(BAD_REFERENT_NAME, ERROR) \
FUNC(BAD_REFTABLE_STACK_COUNT, ERROR) \
+ FUNC(BAD_REFTABLE_STACK_LIST_NEWLINE, ERROR) \
FUNC(BAD_REFTABLE_TABLE_NAME, ERROR) \
FUNC(BAD_REF_CONTENT, ERROR) \
FUNC(BAD_REF_FILETYPE, ERROR) \
diff --git a/refs/reftable-backend.c b/refs/reftable-backend.c
index 616f4ee0f3..0087afa3ac 100644
--- a/refs/reftable-backend.c
+++ b/refs/reftable-backend.c
@@ -2698,6 +2698,9 @@ static int reftable_fsck_error_handler(struct reftable_fsck_info info,
case REFTABLE_FSCK_ERROR_STACK_COUNT:
msg_id = FSCK_MSG_BAD_REFTABLE_STACK_COUNT;
break;
+ case REFTABLE_FSCK_ERROR_STACK_LIST_MISSING_NEWLINE:
+ msg_id = FSCK_MSG_BAD_REFTABLE_STACK_LIST_NEWLINE;
+ break;
default:
BUG("unknown fsck error: %d", info.error);
}
diff --git a/reftable/fsck.c b/reftable/fsck.c
index e92a630276..b4898fd2cd 100644
--- a/reftable/fsck.c
+++ b/reftable/fsck.c
@@ -1,7 +1,31 @@
#include "basics.h"
+#include "reftable-error.h"
#include "reftable-fsck.h"
#include "stack.h"
+static int reftable_fsck_stack_contains_newline(const char *list_file)
+{
+ FILE *f = fopen(list_file, "r");
+ int c = 0;
+
+ if (f == NULL) {
+ if (errno == ENOENT)
+ return 0;
+ return REFTABLE_IO_ERROR;
+ }
+
+ if (fseek(f, 0, SEEK_END) == 0) {
+ long size = ftell(f);
+ if (size <= 0)
+ return REFTABLE_IO_ERROR;
+ fseek(f, -1, SEEK_END);
+ c = fgetc(f);
+ }
+ fclose(f);
+
+ return c == '\n';
+}
+
static int reftable_fsck_valid_stack_count(struct reftable_stack *st)
{
DIR *dir = opendir(st->reftable_dir);
@@ -66,6 +90,18 @@ int reftable_fsck_check(struct reftable_stack *stack,
}
}
+ verbose_fn("Checking trailing newline in stack list", cb_data);
+
+ if (!reftable_fsck_stack_contains_newline(stack->list_file)) {
+ struct reftable_fsck_info info = {
+ .error = REFTABLE_FSCK_ERROR_STACK_LIST_MISSING_NEWLINE,
+ .path = stack->list_file,
+ .msg = "trailing newline missing in stack list"
+ };
+
+ err = report_fn(info, cb_data);
+ }
+
verbose_fn("Checking reftable tables count", cb_data);
if (!reftable_fsck_valid_stack_count(stack)) {
diff --git a/reftable/reftable-fsck.h b/reftable/reftable-fsck.h
index 888c3968b7..8e6cb6c7d2 100644
--- a/reftable/reftable-fsck.h
+++ b/reftable/reftable-fsck.h
@@ -8,6 +8,8 @@ enum reftable_fsck_error {
REFTABLE_FSCK_ERROR_TABLE_NAME = -1,
/* Incorrect number of tables present */
REFTABLE_FSCK_ERROR_STACK_COUNT = -2,
+ /* Newline missing at the end of the stack list */
+ REFTABLE_FSCK_ERROR_STACK_LIST_MISSING_NEWLINE = -3,
};
/* Represents an individual error encounctered during the FSCK checks. */
diff --git a/t/t0614-reftable-fsck.sh b/t/t0614-reftable-fsck.sh
index a351fed562..937c5dd37a 100755
--- a/t/t0614-reftable-fsck.sh
+++ b/t/t0614-reftable-fsck.sh
@@ -52,4 +52,25 @@ test_expect_success 'table count should be checked' '
)
'
+test_expect_success 'stack list must contain trailing newline' '
+ test_when_finished "rm -rf repo" &&
+ git init repo &&
+ (
+ cd repo &&
+ git commit --allow-empty -m initial &&
+
+ git refs verify 2>err &&
+ test_must_be_empty err &&
+
+ printf "%s" "$(cat .git/reftable/tables.list)" >.git/reftable/tables.list.tmp &&
+ mv .git/reftable/tables.list.tmp .git/reftable/tables.list &&
+
+ test_must_fail git refs verify 2>err &&
+ cat >expect <<-EOF &&
+ error: $(pwd)/.git/reftable/tables.list: badReftableStackListNewline: trailing newline missing in stack list
+ EOF
+ test_cmp expect err
+ )
+'
+
test_done
--
2.50.1
