Skip to content

fix: Bounds-check read_from_file restores with snprintf #64

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
VedantMadane wants to merge 2 commits into
base: main
Choose a base branch
from
Open

fix: Bounds-check read_from_file restores with snprintf #64

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
01cfa96
fix: pass output_size to read_from_file and bounds-check with snprintf
VedantMadane Sep 3, 2026
645d41c
fix: pass output size into read_from_file
VedantMadane Sep 17, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 8 additions & 0 deletions _pr_meta.json
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,8 @@
{
"repo": "RomanAlexandroff/42-Smart-Cluster-Sign",
"number": 64,
"base": "main",
"head": "fix/issue-34",
"fork": "VedantMadane/RomanAlexandroff-42-Smart-Cluster-Sign",
"title": "fix: Bounds-check read_from_file restores with snprintf"
}
2 changes: 1 addition & 1 deletion src/42-Smart-Cluster-Sign.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -59,7 +59,7 @@ ERROR_t secret_verification(String text);
void data_restore(const char* file_name);
void data_integrity_check(void);
ERROR_t write_to_file(const char* file_name, char* input);
ERROR_t read_from_file(const char* file_name, char* output);
ERROR_t read_from_file(const char* file_name, char* output, size_t output_size);
ERROR_t file_sys_init(void);

/* ota.cpp */
Expand Down
20 changes: 10 additions & 10 deletions src/file_system.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -23,20 +23,20 @@ ERROR_t secret_verification(String input)
return (FS_NOT_A_SECRET);
if (input.substring(0, 1) != "s")
return (FS_NOT_A_SECRET);
strcpy(secret_buffer, rtc_g.Secret);
snprintf(secret_buffer, sizeof(secret_buffer), "%s", rtc_g.Secret);
exam_status_buffer = rtc_g.exam_status;
input.toCharArray(rtc_g.Secret, sizeof(rtc_g.Secret));
intra_result = fetch_exams();
strcpy(rtc_g.Secret, secret_buffer);
snprintf(rtc_g.Secret, sizeof(rtc_g.Secret), "%s", secret_buffer);
rtc_g.exam_status = exam_status_buffer;
if (intra_result == INTRA_NO_TOKEN || intra_result == INTRA_NO_SERVER)
return (FS_INVALID_SECRET);
return (FS_VALID_SECRET);
}

static void restore_data_value(const char* file_name, char* destination, const char* variable_name)
static void restore_data_value(const char* file_name, char* destination, size_t destination_size, const char* variable_name)
{
if (read_from_file(file_name, destination) == FS_OK)
if (read_from_file(file_name, destination, destination_size) == FS_OK)
DEBUG_PRINTF("\n[FILE SYSTEM] Successfully restored data from %s.\n", file_name);
else
DEBUG_PRINTF("\n[FILE SYSTEM] Failed to restore data from %s!\n", file_name);
Expand All @@ -49,9 +49,9 @@ void data_restore(const char* file_name)
return;
watchdog_reset();
if (strcmp(file_name, "/secret.txt") == 0)
restore_data_value(file_name, rtc_g.Secret, "rtc_g.Secret");
restore_data_value(file_name, rtc_g.Secret, sizeof(rtc_g.Secret), "rtc_g.Secret");
else if (strcmp(file_name, "/chat_id.txt") == 0)
restore_data_value(file_name, rtc_g.chat_id, "rtc_g.chat_id");
restore_data_value(file_name, rtc_g.chat_id, sizeof(rtc_g.chat_id), "rtc_g.chat_id");
}

void data_integrity_check(void)
Expand Down Expand Up @@ -83,7 +83,7 @@ void data_integrity_check(void)
data_restore("/chat_id.txt");
if (!rtc_g.from_name[0])
{
strcpy(rtc_g.from_name, "User");
snprintf(rtc_g.from_name, sizeof(rtc_g.from_name), "%s", "User");
DEBUG_PRINTF("\n[FILE SYSTEM] User name has been set to: %s\n", rtc_g.from_name);
}
}
Expand Down Expand Up @@ -116,13 +116,13 @@ ERROR_t write_to_file(const char* file_name, char* input)
return FS_OK;
}

ERROR_t read_from_file(const char* file_name, char* output)
ERROR_t read_from_file(const char* file_name, char* output, size_t output_size)
{
File file;
short i;
String buffer;

if (!file_name)
if (!file_name || !output || output_size == 0)
return FS_ENTRY_ERROR;
i = 0;
watchdog_reset();
Expand All @@ -145,7 +145,7 @@ ERROR_t read_from_file(const char* file_name, char* output)
buffer.trim();
if (buffer.length() == 0)
return FS_EMPTY_FILE;
strcpy(output, buffer.c_str());
snprintf(output, output_size, "%s", buffer.c_str());
return FS_OK;
}

Expand Down