diff --git a/src/tools/miri/src/shims/extern_static.rs b/src/tools/miri/src/shims/extern_static.rs index 5cec51e96048..c3c7ef7c1fd8 100644 --- a/src/tools/miri/src/shims/extern_static.rs +++ b/src/tools/miri/src/shims/extern_static.rs @@ -16,8 +16,8 @@ impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> { /// Zero-initialized pointer-sized extern statics are pretty common. /// Most of them are for weak symbols, which we all set to null (indicating that the - /// symbol is not supported, and triggering fallback code which ends up calling a - /// syscall that we do support). + /// symbol is not supported, and triggering fallback code which ends up calling + /// some other shim that we do support). fn null_ptr_extern_statics( this: &mut MiriInterpCx<'mir, 'tcx>, names: &[&str], @@ -59,8 +59,9 @@ impl<'mir, 'tcx> MiriMachine<'mir, 'tcx> { "linux" => { Self::null_ptr_extern_statics( this, - &["__cxa_thread_atexit_impl", "getrandom", "statx", "__clock_gettime64"], + &["__cxa_thread_atexit_impl", "__clock_gettime64"], )?; + Self::weak_symbol_extern_statics(this, &["getrandom", "statx"])?; // "environ" let environ = this.machine.env_vars.unix().environ(); Self::add_extern_static(this, "environ", environ); diff --git a/src/tools/miri/src/shims/unix/fd.rs b/src/tools/miri/src/shims/unix/fd.rs index 566988cba1f8..e536b78d1c0b 100644 --- a/src/tools/miri/src/shims/unix/fd.rs +++ b/src/tools/miri/src/shims/unix/fd.rs @@ -17,6 +17,7 @@ use crate::*; pub trait FileDescription: std::fmt::Debug + Any { fn name(&self) -> &'static str; + /// Reads as much as possible into the given buffer, and returns the number of bytes read. fn read<'tcx>( &mut self, _communicate_allowed: bool, @@ -26,6 +27,7 @@ pub trait FileDescription: std::fmt::Debug + Any { throw_unsup_format!("cannot read from {}", self.name()); } + /// Writes as much as possible from the given buffer, and returns the number of bytes written. fn write<'tcx>( &mut self, _communicate_allowed: bool, @@ -35,6 +37,8 @@ pub trait FileDescription: std::fmt::Debug + Any { throw_unsup_format!("cannot write to {}", self.name()); } + /// Seeks to the given offset (which can be relative to the beginning, end, or current position). + /// Returns the new position from the start of the stream. fn seek<'tcx>( &mut self, _communicate_allowed: bool, diff --git a/src/tools/miri/src/shims/unix/linux/foreign_items.rs b/src/tools/miri/src/shims/unix/linux/foreign_items.rs index 58ffd5fc1e03..71cdc3be8147 100644 --- a/src/tools/miri/src/shims/unix/linux/foreign_items.rs +++ b/src/tools/miri/src/shims/unix/linux/foreign_items.rs @@ -12,7 +12,7 @@ use shims::unix::linux::mem::EvalContextExt as _; use shims::unix::linux::sync::futex; pub fn is_dyn_sym(name: &str) -> bool { - matches!(name, "getrandom") + matches!(name, "getrandom" | "statx") } impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {} @@ -29,7 +29,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> { // See `fn emulate_foreign_item_inner` in `shims/foreign_items.rs` for the general pattern. match link_name.as_str() { - // File related shims (but also see "syscall" below for statx) + // File related shims "readdir64" => { let [dirp] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?; let result = this.linux_readdir64(dirp)?; @@ -41,6 +41,12 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> { let result = this.sync_file_range(fd, offset, nbytes, flags)?; this.write_scalar(result, dest)?; } + "statx" => { + let [dirfd, pathname, flags, mask, statxbuf] = + this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?; + let result = this.linux_statx(dirfd, pathname, flags, mask, statxbuf)?; + this.write_scalar(Scalar::from_i32(result), dest)?; + } // epoll, eventfd "epoll_create1" => { @@ -113,7 +119,6 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> { // have the right type. let sys_getrandom = this.eval_libc("SYS_getrandom").to_target_usize(this)?; - let sys_statx = this.eval_libc("SYS_statx").to_target_usize(this)?; let sys_futex = this.eval_libc("SYS_futex").to_target_usize(this)?; if args.is_empty() { @@ -134,20 +139,6 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> { } getrandom(this, &args[1], &args[2], &args[3], dest)?; } - // `statx` is used by `libstd` to retrieve metadata information on `linux` - // instead of using `stat`,`lstat` or `fstat` as on `macos`. - id if id == sys_statx => { - // The first argument is the syscall id, so skip over it. - if args.len() < 6 { - throw_ub_format!( - "incorrect number of arguments for `statx` syscall: got {}, expected at least 6", - args.len() - ); - } - let result = - this.linux_statx(&args[1], &args[2], &args[3], &args[4], &args[5])?; - this.write_scalar(Scalar::from_target_isize(result.into(), this), dest)?; - } // `futex` is used by some synchronization primitives. id if id == sys_futex => { futex(this, &args[1..], dest)?; diff --git a/src/tools/miri/tests/pass/alloc-access-tracking.rs b/src/tools/miri/tests/pass/alloc-access-tracking.rs index 29c1ee2f7b76..a226783155b4 100644 --- a/src/tools/miri/tests/pass/alloc-access-tracking.rs +++ b/src/tools/miri/tests/pass/alloc-access-tracking.rs @@ -1,7 +1,8 @@ #![feature(start)] #![no_std] -//@compile-flags: -Zmiri-track-alloc-id=18 -Zmiri-track-alloc-accesses -Cpanic=abort -//@only-target-linux: alloc IDs differ between OSes for some reason +//@compile-flags: -Zmiri-track-alloc-id=20 -Zmiri-track-alloc-accesses -Cpanic=abort +//@normalize-stderr-test: "id 20" -> "id $$ALLOC" +//@only-target-linux: alloc IDs differ between OSes (due to extern static allocations) extern "Rust" { fn miri_alloc(size: usize, align: usize) -> *mut u8; diff --git a/src/tools/miri/tests/pass/alloc-access-tracking.stderr b/src/tools/miri/tests/pass/alloc-access-tracking.stderr index bef13701ea2c..0af6cde833f7 100644 --- a/src/tools/miri/tests/pass/alloc-access-tracking.stderr +++ b/src/tools/miri/tests/pass/alloc-access-tracking.stderr @@ -2,7 +2,7 @@ note: tracking was triggered --> $DIR/alloc-access-tracking.rs:LL:CC | LL | let ptr = miri_alloc(123, 1); - | ^^^^^^^^^^^^^^^^^^ created Miri bare-metal heap allocation of 123 bytes (alignment ALIGN bytes) with id 18 + | ^^^^^^^^^^^^^^^^^^ created Miri bare-metal heap allocation of 123 bytes (alignment ALIGN bytes) with id $ALLOC | = note: BACKTRACE: = note: inside `start` at $DIR/alloc-access-tracking.rs:LL:CC @@ -11,7 +11,7 @@ note: tracking was triggered --> $DIR/alloc-access-tracking.rs:LL:CC | LL | *ptr = 42; // Crucially, only a write is printed here, no read! - | ^^^^^^^^^ write access to allocation with id 18 + | ^^^^^^^^^ write access to allocation with id $ALLOC | = note: BACKTRACE: = note: inside `start` at $DIR/alloc-access-tracking.rs:LL:CC @@ -20,7 +20,7 @@ note: tracking was triggered --> $DIR/alloc-access-tracking.rs:LL:CC | LL | assert_eq!(*ptr, 42); - | ^^^^^^^^^^^^^^^^^^^^ read access to allocation with id 18 + | ^^^^^^^^^^^^^^^^^^^^ read access to allocation with id $ALLOC | = note: BACKTRACE: = note: inside `start` at RUSTLIB/core/src/macros/mod.rs:LL:CC @@ -30,7 +30,7 @@ note: tracking was triggered --> $DIR/alloc-access-tracking.rs:LL:CC | LL | miri_dealloc(ptr, 123, 1); - | ^^^^^^^^^^^^^^^^^^^^^^^^^ freed allocation with id 18 + | ^^^^^^^^^^^^^^^^^^^^^^^^^ freed allocation with id $ALLOC | = note: BACKTRACE: = note: inside `start` at $DIR/alloc-access-tracking.rs:LL:CC