From bcc06e10c6393108fee56abf514ad8eb31fc4b56 Mon Sep 17 00:00:00 2001
From: Andrea Mazzoleni <amadvance@gmail.com>
Date: Thu, 24 Sep 2026 20:40:27 +0200
Subject: [PATCH] Reject parity sizes exceeding data_off_t range and remove
 redundant block size casts

---
 cmdline/check.c  | 2 +-
 cmdline/handle.c | 4 ++--
 cmdline/parity.c | 9 +++++++--
 cmdline/search.c | 2 +-
 cmdline/state.c  | 2 +-
 cmdline/sync.c   | 4 ++--
 6 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/cmdline/check.c b/cmdline/check.c
index 9795a2d7..bf209a15 100644
--- a/cmdline/check.c
+++ b/cmdline/check.c
@@ -3087,7 +3087,7 @@ int state_check(struct snapraid_state* state, int fix, block_off_t blockstart, b
 	 */
 
 	blockmax = parity_allocated_size(state);
-	size = blockmax * (data_off_t)state->block_size;
+	size = blockmax * state->block_size;
 
 	if (blockstart > blockmax) {
 		/* LCOV_EXCL_START */
diff --git a/cmdline/handle.c b/cmdline/handle.c
index d721f045..e532fb53 100644
--- a/cmdline/handle.c
+++ b/cmdline/handle.c
@@ -375,7 +375,7 @@ ssize_t handle_read(struct snapraid_handle* handle, block_off_t file_pos, unsign
 	unsigned count;
 	int ret;
 
-	offset = file_pos * (data_off_t)block_size;
+	offset = file_pos * block_size;
 
 	if (!out_missing)
 		out_missing = log_error;
@@ -456,7 +456,7 @@ int handle_write(struct snapraid_handle* handle, block_off_t file_pos, unsigned
 		/* LCOV_EXCL_STOP */
 	}
 
-	offset = file_pos * (data_off_t)block_size;
+	offset = file_pos * block_size;
 
 	write_size = file_block_size(handle->file, file_pos, block_size);
 
diff --git a/cmdline/parity.c b/cmdline/parity.c
index 09b9b4d7..c3e7dadc 100644
--- a/cmdline/parity.c
+++ b/cmdline/parity.c
@@ -44,6 +44,11 @@ block_off_t parity_allocated_size(struct snapraid_state* state)
 			parity_block = block;
 	}
 
+	if (parity_block > (block_off_t)INT64_MAX / state->block_size) {
+		log_fatal(ESOFT, "Parity with %" PRIu64 " blocks is too large for block size %u.\n", parity_block, state->block_size);
+		exit(EXIT_FAILURE);
+	}
+
 	return parity_block;
 }
 
@@ -1083,7 +1088,7 @@ int parity_write(struct snapraid_parity_handle* handle, block_off_t pos, unsigne
 	unsigned count;
 	int ret;
 
-	offset = pos * (data_off_t)block_size;
+	offset = pos * block_size;
 
 	split = parity_split_find(handle, &offset);
 	if (!split) {
@@ -1177,7 +1182,7 @@ int parity_read(struct snapraid_parity_handle* handle, block_off_t pos, unsigned
 	struct snapraid_split_handle* split;
 	int ret;
 
-	offset = pos * (data_off_t)block_size;
+	offset = pos * block_size;
 
 	split = parity_split_find(handle, &offset);
 	if (!split) {
diff --git a/cmdline/search.c b/cmdline/search.c
index ed9a6583..de65001c 100644
--- a/cmdline/search.c
+++ b/cmdline/search.c
@@ -137,7 +137,7 @@ int state_search_fetch(struct snapraid_state* state, int prevhash, struct snapra
 	arg.block = missing_block;
 	arg.file = missing_file;
 	arg.buffer = buffer;
-	arg.offset = state->block_size * (data_off_t)missing_file_pos;
+	arg.offset = state->block_size * missing_file_pos;
 	arg.read_size = file_block_size(missing_file, missing_file_pos, state->block_size);
 	arg.prevhash = prevhash;
 
diff --git a/cmdline/state.c b/cmdline/state.c
index 976dce98..bed83c95 100644
--- a/cmdline/state.c
+++ b/cmdline/state.c
@@ -2950,7 +2950,7 @@ static void state_read_content(struct snapraid_state* state, const char* path, S
 					 * Allocate without initializing blocks. This deleted run sets every
 					 * state and hash before the file is inserted in the extent map.
 					 */
-					deleted = file_alloc(state->block_size, "<deleted>", v_count * (data_off_t)state->block_size, 0, 0, 0);
+					deleted = file_alloc(state->block_size, "<deleted>", v_count * state->block_size, 0, 0, 0);
 
 					/* mark the file as deleted */
 					file_flag_set(deleted, FILE_IS_DELETED);
diff --git a/cmdline/sync.c b/cmdline/sync.c
index fda79533..c7dd36d0 100644
--- a/cmdline/sync.c
+++ b/cmdline/sync.c
@@ -2019,11 +2019,11 @@ int state_sync(struct snapraid_state* state, block_off_t blockstart, block_off_t
 	 * but must not be shorter than used_size (which indicates missing parity).
 	 */
 	blockmax = parity_allocated_size(state);
-	size = blockmax * (data_off_t)state->block_size;
+	size = blockmax * state->block_size;
 
 	/* minimum size of the parity files we expect */
 	used_paritymax = parity_used_size(state);
-	used_parity_size = used_paritymax * (data_off_t)state->block_size;
+	used_parity_size = used_paritymax * state->block_size;
 
 	if (blockstart > blockmax) {
 		/* LCOV_EXCL_START */