Callbacks must not be able to unwind into sqlite code

src/busy.rs

@@ -1,6 +1,7 @@
 ///! Busy handler (when the database is locked)
 use std::mem;
 use std::os::raw::{c_int, c_void};
+use std::panic::catch_unwind;
 use std::ptr;
 use std::time::Duration;
 
@@ -48,7 +49,7 @@ impl Connection {
     pub fn busy_handler(&self, callback: Option<fn(i32) -> bool>) -> Result<()> {
         unsafe extern "C" fn busy_handler_callback(p_arg: *mut c_void, count: c_int) -> c_int {
             let handler_fn: fn(i32) -> bool = mem::transmute(p_arg);
-            if handler_fn(count) {
+            if let Ok(true) = catch_unwind(|| handler_fn(count)) {
                 1
             } else {
                 0

src/error.rs

@@ -91,6 +91,9 @@ pub enum Error {
     #[cfg(feature = "vtab")]
     #[allow(dead_code)]
     ModuleError(String),
+
+    #[cfg(feature = "functions")]
+    UnwindingPanic,
 }
 
 impl From<str::Utf8Error> for Error {
@@ -151,6 +154,8 @@ impl fmt::Display for Error {
             Error::InvalidQuery => write!(f, "Query is not read-only"),
             #[cfg(feature = "vtab")]
             Error::ModuleError(ref desc) => write!(f, "{}", desc),
+            #[cfg(feature = "functions")]
+            Error::UnwindingPanic => write!(f, "unwinding panic"),
         }
     }
 }
@@ -188,6 +193,8 @@ impl error::Error for Error {
             Error::InvalidQuery => "query is not read-only",
             #[cfg(feature = "vtab")]
             Error::ModuleError(ref desc) => desc,
+            #[cfg(feature = "functions")]
+            Error::UnwindingPanic => "unwinding panic",
         }
     }
 
@@ -222,6 +229,9 @@ impl error::Error for Error {
 
             #[cfg(feature = "vtab")]
             Error::ModuleError(_) => None,
+
+            #[cfg(feature = "functions")]
+            Error::UnwindingPanic => None,
         }
     }
 }

src/functions.rs

@@ -55,6 +55,7 @@
 //! ```
 use std::error::Error as StdError;
 use std::os::raw::{c_int, c_void};
+use std::panic::{catch_unwind, RefUnwindSafe, UnwindSafe};
 use std::ptr;
 use std::slice;
 
@@ -189,6 +190,7 @@ impl<'a> Context<'a> {
 /// result. Implementations should be stateless.
 pub trait Aggregate<A, T>
 where
+    A: RefUnwindSafe + UnwindSafe,
     T: ToSql,
 {
     /// Initializes the aggregation context. Will be called prior to the first
@@ -246,7 +248,7 @@ impl Connection {
         x_func: F,
     ) -> Result<()>
     where
-        F: FnMut(&Context<'_>) -> Result<T> + Send + 'static,
+        F: FnMut(&Context<'_>) -> Result<T> + Send + UnwindSafe + 'static,
         T: ToSql,
     {
         self.db
@@ -267,6 +269,7 @@ impl Connection {
         aggr: D,
     ) -> Result<()>
     where
+        A: RefUnwindSafe + UnwindSafe,
         D: Aggregate<A, T>,
         T: ToSql,
     {
@@ -297,7 +300,7 @@ impl InnerConnection {
         x_func: F,
     ) -> Result<()>
     where
-        F: FnMut(&Context<'_>) -> Result<T> + Send + 'static,
+        F: FnMut(&Context<'_>) -> Result<T> + Send + UnwindSafe + 'static,
         T: ToSql,
     {
         unsafe extern "C" fn call_boxed_closure<F, T>(
@@ -308,20 +311,28 @@ impl InnerConnection {
             F: FnMut(&Context<'_>) -> Result<T>,
             T: ToSql,
         {
+            let r = catch_unwind(|| {
+                let boxed_f: *mut F = ffi::sqlite3_user_data(ctx) as *mut F;
+                assert!(!boxed_f.is_null(), "Internal error - null function pointer");
                 let ctx = Context {
                     ctx,
                     args: slice::from_raw_parts(argv, argc as usize),
                 };
-            let boxed_f: *mut F = ffi::sqlite3_user_data(ctx.ctx) as *mut F;
+                (*boxed_f)(&ctx)
-            assert!(!boxed_f.is_null(), "Internal error - null function pointer");
+            });
-
+            let t = match r {
-            let t = (*boxed_f)(&ctx);
+                Err(_) => {
+                    report_error(ctx, &Error::UnwindingPanic);
+                    return;
+                }
+                Ok(r) => r,
+            };
             let t = t.as_ref().map(|t| ToSql::to_sql(t));
 
             match t {
-                Ok(Ok(ref value)) => set_result(ctx.ctx, value),
+                Ok(Ok(ref value)) => set_result(ctx, value),
-                Ok(Err(err)) => report_error(ctx.ctx, &err),
+                Ok(Err(err)) => report_error(ctx, &err),
-                Err(err) => report_error(ctx.ctx, err),
+                Err(err) => report_error(ctx, err),
             }
         }
 
@@ -355,6 +366,7 @@ impl InnerConnection {
         aggr: D,
     ) -> Result<()>
     where
+        A: RefUnwindSafe + UnwindSafe,
         D: Aggregate<A, T>,
         T: ToSql,
     {
@@ -374,15 +386,10 @@ impl InnerConnection {
             argc: c_int,
             argv: *mut *mut sqlite3_value,
         ) where
+            A: RefUnwindSafe + UnwindSafe,
             D: Aggregate<A, T>,
             T: ToSql,
         {
-            let boxed_aggr: *mut D = ffi::sqlite3_user_data(ctx) as *mut D;
-            assert!(
-                !boxed_aggr.is_null(),
-                "Internal error - null aggregate pointer"
-            );
-
             let pac = match aggregate_context(ctx, ::std::mem::size_of::<*mut A>()) {
                 Some(pac) => pac,
                 None => {
@@ -391,32 +398,40 @@ impl InnerConnection {
                 }
             };
 
-            if (*pac as *mut A).is_null() {
+            let r = catch_unwind(|| {
-                *pac = Box::into_raw(Box::new((*boxed_aggr).init()));
-            }
-
-            let mut ctx = Context {
-                ctx,
-                args: slice::from_raw_parts(argv, argc as usize),
-            };
-
-            match (*boxed_aggr).step(&mut ctx, &mut **pac) {
-                Ok(_) => {}
-                Err(err) => report_error(ctx.ctx, &err),
-            };
-        }
-
-        unsafe extern "C" fn call_boxed_final<A, D, T>(ctx: *mut sqlite3_context)
-        where
-            D: Aggregate<A, T>,
-            T: ToSql,
-        {
                 let boxed_aggr: *mut D = ffi::sqlite3_user_data(ctx) as *mut D;
                 assert!(
                     !boxed_aggr.is_null(),
                     "Internal error - null aggregate pointer"
                 );
+                if (*pac as *mut A).is_null() {
+                    *pac = Box::into_raw(Box::new((*boxed_aggr).init()));
+                }
+                let mut ctx = Context {
+                    ctx,
+                    args: slice::from_raw_parts(argv, argc as usize),
+                };
+                (*boxed_aggr).step(&mut ctx, &mut **pac)
+            });
+            let r = match r {
+                Err(_) => {
+                    report_error(ctx, &Error::UnwindingPanic);
+                    return;
+                }
+                Ok(r) => r,
+            };
+            match r {
+                Ok(_) => {}
+                Err(err) => report_error(ctx, &err),
+            };
+        }
 
+        unsafe extern "C" fn call_boxed_final<A, D, T>(ctx: *mut sqlite3_context)
+        where
+            A: RefUnwindSafe + UnwindSafe,
+            D: Aggregate<A, T>,
+            T: ToSql,
+        {
             // Within the xFinal callback, it is customary to set N=0 in calls to
             // sqlite3_aggregate_context(C,N) so that no pointless memory allocations occur.
             let a: Option<A> = match aggregate_context(ctx, 0) {
@@ -431,7 +446,21 @@ impl InnerConnection {
                 None => None,
             };
 
-            let t = (*boxed_aggr).finalize(a);
+            let r = catch_unwind(|| {
+                let boxed_aggr: *mut D = ffi::sqlite3_user_data(ctx) as *mut D;
+                assert!(
+                    !boxed_aggr.is_null(),
+                    "Internal error - null aggregate pointer"
+                );
+                (*boxed_aggr).finalize(a)
+            });
+            let t = match r {
+                Err(_) => {
+                    report_error(ctx, &Error::UnwindingPanic);
+                    return;
+                }
+                Ok(r) => r,
+            };
             let t = t.as_ref().map(|t| ToSql::to_sql(t));
             match t {
                 Ok(Ok(ref value)) => set_result(ctx, value),

src/hooks.rs

@@ -2,6 +2,7 @@
 #![allow(non_camel_case_types)]
 
 use std::os::raw::{c_char, c_int, c_void};
+use std::panic::catch_unwind;
 use std::ptr;
 
 use crate::ffi;
@@ -146,8 +147,11 @@ impl InnerConnection {
         where
             F: FnMut() -> bool,
         {
+            let r = catch_unwind(|| {
                 let boxed_hook: *mut F = p_arg as *mut F;
-            if (*boxed_hook)() {
+                (*boxed_hook)()
+            });
+            if let Ok(true) = r {
                 1
             } else {
                 0
@@ -192,8 +196,10 @@ impl InnerConnection {
         where
             F: FnMut(),
         {
+            let _ = catch_unwind(|| {
                 let boxed_hook: *mut F = p_arg as *mut F;
                 (*boxed_hook)();
+            });
         }
 
         let free_rollback_hook = if hook.is_some() {
@@ -239,8 +245,6 @@ impl InnerConnection {
             use std::ffi::CStr;
             use std::str;
 
-            let boxed_hook: *mut F = p_arg as *mut F;
-
             let action = Action::from(action_code);
             let db_name = {
                 let c_slice = CStr::from_ptr(db_str).to_bytes();
@@ -251,7 +255,10 @@ impl InnerConnection {
                 str::from_utf8_unchecked(c_slice)
             };
 
+            let _ = catch_unwind(|| {
+                let boxed_hook: *mut F = p_arg as *mut F;
                 (*boxed_hook)(action, db_name, tbl_name, row_id);
+            });
         }
 
         let free_update_hook = if hook.is_some() {

src/trace.rs

@@ -3,6 +3,7 @@
 use std::ffi::{CStr, CString};
 use std::mem;
 use std::os::raw::{c_char, c_int, c_void};
+use std::panic::catch_unwind;
 use std::ptr;
 use std::time::Duration;
 
@@ -27,7 +28,7 @@ pub unsafe fn config_log(callback: Option<fn(c_int, &str)>) -> Result<()> {
         let callback: fn(c_int, &str) = unsafe { mem::transmute(p_arg) };
 
         let s = String::from_utf8_lossy(c_slice);
-        callback(err, &s);
+        let _ = catch_unwind(|| callback(err, &s));
     }
 
     let rc = match callback {
@@ -72,7 +73,7 @@ impl Connection {
             let trace_fn: fn(&str) = mem::transmute(p_arg);
             let c_slice = CStr::from_ptr(z_sql).to_bytes();
             let s = String::from_utf8_lossy(c_slice);
-            trace_fn(&s);
+            let _ = catch_unwind(|| trace_fn(&s));
         }
 
         let c = self.db.borrow_mut();
@@ -106,7 +107,7 @@ impl Connection {
                 nanoseconds / NANOS_PER_SEC,
                 (nanoseconds % NANOS_PER_SEC) as u32,
             );
-            profile_fn(&s, duration);
+            let _ = catch_unwind(|| profile_fn(&s, duration));
         }
 
         let c = self.db.borrow_mut();

src/unlock_notify.rs

@@ -4,6 +4,8 @@ use std::os::raw::c_int;
 #[cfg(feature = "unlock_notify")]
 use std::os::raw::c_void;
 #[cfg(feature = "unlock_notify")]
+use std::panic::catch_unwind;
+#[cfg(feature = "unlock_notify")]
 use std::sync::{Condvar, Mutex};
 
 use crate::ffi;
@@ -42,8 +44,10 @@ unsafe extern "C" fn unlock_notify_cb(ap_arg: *mut *mut c_void, n_arg: c_int) {
     use std::slice::from_raw_parts;
     let args = from_raw_parts(ap_arg, n_arg as usize);
     for arg in args {
+        let _ = catch_unwind(|| {
             let un: &mut UnlockNotification = &mut *(*arg as *mut UnlockNotification);
-        un.fired();
+            un.fired()
+        });
     }
 }