std::fs::Metadata timestamp methods will panic on files with invalid timestamp nsec values #108277
Description
std::fs::Metadata timestamp methods (like created) will panic on files with invalid timestamp nsec values.`
It will panic here:
thread 'async-std/runtime' panicked at 'assertion failed: tv_nsec >= 0 && tv_nsec < NSEC_PER_SEC as i64', library/std/src/sys/unix/time.rs:66:9
We have recently stumbled upon multiple btrfs users that happen to have files that look something like this:
# stat ./.temp-FOYNU1 File: ./.temp-FOYNU1 Size: 37271 Blocks: 80 IO Block: 4096 regular file Device: 0,40 Inode: 4024244 Links: 1 Access: (0600/-rw-------) Uid: ( 1000/ x) Gid: ( 1000/ x) Context: unconfined_u:object_r:gkeyringd_gnome_home_t:s0 Access: 2023-02-19 21:35:19.087361106 +0100 Modify: 2022-10-29 09:48:58.344737238 +0200 Change: 2022-10-29 09:48:58.344737238 +0200 Birth: 5006491383123099853.-1424152917 This is most likely a filesystem / kernel bug. But these files / broken kernels exist now and will cause any access to ctime (and possible the other time values) to panic.
My proposal would be to check bounds of the underlying syscall results and return an appropriate Err for these broken time values if the ctime / mtime / atime etc. contains values that would otherwise trigger this assertion.
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rustc --version --verbose:
rustc 1.67.1 (d5a82bbd2 2023-02-07) binary: rustc commit-hash: d5a82bbd26e1ad8b7401f6a718a9c57c96905483 commit-date: 2023-02-07 host: x86_64-unknown-linux-gnu release: 1.67.1 LLVM version: 15.0.6 Backtrace
0: 0x556e2422048a - std::backtrace_rs::backtrace::libunwind::trace::h79937bc171ada62c at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5 1: 0x556e2422048a - std::backtrace_rs::backtrace::trace_unsynchronized::h2292bca8571cb919 at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5 2: 0x556e2422048a - std::sys_common::backtrace::_print_fmt::h9c461f248e4ae90d at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/sys_common/backtrace.rs:65:5 3: 0x556e2422048a - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::he9fe6bf1a39182e1 at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/sys_common/backtrace.rs:44:22 4: 0x556e2424687e - core::fmt::write::h032658c119c720d7 at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/core/src/fmt/mod.rs:1208:17 5: 0x556e24219c65 - std::io::Write::write_fmt::h299fc90dfae41c0d at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/io/mod.rs:1682:15 6: 0x556e24220255 - std::sys_common::backtrace::_print::heb70d25df9937e3f at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/sys_common/backtrace.rs:47:5 7: 0x556e24220255 - std::sys_common::backtrace::print::had745c0a76b8b521 at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/sys_common/backtrace.rs:34:9 8: 0x556e24221cff - std::panicking::default_hook::{{closure}}::h1ea782cdfa2fd097 at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/panicking.rs:267:22 9: 0x556e24221a3b - std::panicking::default_hook::h1cc3af63455a163c at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/panicking.rs:286:9 10: 0x556e2422240c - std::panicking::rust_panic_with_hook::h5cafdc4b3bfd5528 at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/panicking.rs:688:13 11: 0x556e24222162 - std::panicking::begin_panic_handler::{{closure}}::hf31c60f40775892c at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/panicking.rs:577:13 12: 0x556e2422093c - std::sys_common::backtrace::__rust_end_short_backtrace::h28a5c7be595826cd at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/sys_common/backtrace.rs:137:18 13: 0x556e24221eb2 - rust_begin_unwind at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/panicking.rs:575:5 14: 0x556e237c2243 - core::panicking::panic_fmt::h8fa27a0b37dd98b7 at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/core/src/panicking.rs:64:14 15: 0x556e237c231d - core::panicking::panic::h545818946343732b at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/core/src/panicking.rs:111:5 16: 0x556e2421704d - std::sys::unix::time::Timespec::new::h0e233601cbadebfd at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/sys/unix/time.rs:66:9 17: 0x556e2421704d - std::sys::unix::time::SystemTime::new::h9d5242895ff4c7e2 at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/sys/unix/time.rs:29:25 18: 0x556e2421704d - std::sys::unix::fs::FileAttr::created::hb18250e52af180d4 at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/sys/unix/fs.rs:485:24 19: 0x556e2421704d - std::fs::Metadata::created::h80fcc7cb446092ab at /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/std/src/fs.rs:1311:9