[BUG] gio::FileExtManual::replace_contents_future() panicking when called with "admin://" URI #1785
Description
I had already posted this on discourse but it seems maybe it was the wrong place as it is not garnering much attention at all, so I'll be filing an issue here as to me this seems like an actual bug of the bindings.
Bug description
I am trying to write to a file that requires elevated privilages. To do so I am using the GIO File API and prefixing the "admin://" URI to the path. My code looks like this:
let admin_uri = format!(
"admin://{}",
file.path()
.expect("File does not have a path?")
.to_string_lossy()
);
let file = gio::File::for_uri(&admin_uri);
// Mount admin volume
let res = file
.mount_enclosing_volume_future(MountMountFlags::NONE, MountOperation::NONE)
.await;
if let Err(e) = res {
println!("Failed to mount admin volume: {e}");
}
println!("Writing with admin perms");
let res = file
.replace_contents_future(
content.clone(),
None,
false,
FileCreateFlags::NONE,
)
.await;
println!("Finished");
if let Err((_, e)) = res {
println!("Failed to write file with admin perms: {e}");
}The writing succeeds, however my program panics.
Backtrace
thread 'main' panicked at /home/aleb/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/glib-0.21.1/src/gstring.rs:2054:9:
assertion failed: !ptr.is_null()
stack backtrace:
0: 0x560ffa3414c2 - std::backtrace_rs::backtrace::libunwind::trace::h74680e970b6e0712
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/../../backtrace/src/backtrace/libunwind.rs:117:9
1: 0x560ffa3414c2 - std::backtrace_rs::backtrace::trace_unsynchronized::ha3bf590e3565a312
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/../../backtrace/src/backtrace/mod.rs:66:14
2: 0x560ffa3414c2 - std::sys::backtrace::_print_fmt::hcf16024cbdd6c458
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/sys/backtrace.rs:66:9
3: 0x560ffa3414c2 - <std::sys::backtrace::BacktraceLock::print::DisplayBacktrace as core::fmt::Display>::fmt::h46a716bba2450163
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/sys/backtrace.rs:39:26
4: 0x560ffa367fb3 - core::fmt::rt::Argument::fmt::ha695e732309707b7
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/fmt/rt.rs:181:76
5: 0x560ffa367fb3 - core::fmt::write::h275e5980d7008551
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/fmt/mod.rs:1446:25
6: 0x560ffa33d553 - std::io::default_write_fmt::hdc4119be3eb77042
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/io/mod.rs:639:11
7: 0x560ffa33d553 - std::io::Write::write_fmt::h561a66a0340b6995
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/io/mod.rs:1914:13
8: 0x560ffa341312 - std::sys::backtrace::BacktraceLock::print::hafb9d5969adc39a0
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/sys/backtrace.rs:42:9
9: 0x560ffa342782 - std::panicking::default_hook::{{closure}}::hae2e97a5c4b2b777
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:300:22
10: 0x560ffa342585 - std::panicking::default_hook::h3db1b505cfc4eb79
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:327:9
11: 0x560ffa343122 - std::panicking::rust_panic_with_hook::h409da73ddef13937
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:833:13
12: 0x560ffa342e96 - std::panicking::begin_panic_handler::{{closure}}::h159b61b27f96a9c2
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:699:13
13: 0x560ffa3419b9 - std::sys::backtrace::__rust_end_short_backtrace::h5b56844d75e766fc
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/sys/backtrace.rs:168:18
14: 0x560ffa342b5d - __rustc[4794b31dd7191200]::rust_begin_unwind
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:697:5
15: 0x560ff99da650 - core::panicking::panic_fmt::hc8737e8cca20a7c8
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/panicking.rs:75:14
16: 0x560ff99da6dc - core::panicking::panic::h4a11c031239f36a8
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/panicking.rs:145:5
17: 0x560ffa2cf9c0 - <glib::gstring::GString as glib::translate::FromGlibPtrFull<*mut u8>>::from_glib_full::h59b7e1e9322a7d6c
at /home/aleb/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/glib-0.21.1/src/gstring.rs:2054:9
18: 0x560ffa2d34e6 - glib::translate::from_glib_full::h1a7ec403c3b5d5e4
at /home/aleb/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/glib-0.21.1/src/translate.rs:1639:5
19: 0x560ffa2cfa57 - <glib::gstring::GString as glib::translate::FromGlibPtrFull<*mut i8>>::from_glib_full::hf9fe6870afdcc37c
at /home/aleb/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/glib-0.21.1/src/gstring.rs:2070:9
20: 0x560ffa2d34c6 - glib::translate::from_glib_full::h14184bbd635d995f
at /home/aleb/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/glib-0.21.1/src/translate.rs:1639:5
21: 0x560ff9bae94e - gio::file::FileExtManual::replace_contents_async::replace_contents_async_trampoline::h4e89b77441005ec6
at /home/aleb/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/gio-0.21.1/src/file.rs:226:31
22: 0x7f32fff6be7c - <unknown>
23: 0x7f32fff71590 - <unknown>
24: 0x7f32fff298d9 - <unknown>
25: 0x7f32fff6be7c - <unknown>
26: 0x7f32fff71590 - <unknown>
27: 0x7f32fff4bed2 - <unknown>
28: 0x7f32fff6be7c - <unknown>
29: 0x7f32fff71590 - <unknown>
30: 0x7f32fff4c46f - <unknown>
31: 0x7f32fff6be7c - <unknown>
32: 0x7f32fff71590 - <unknown>
33: 0x7f32ec94dc84 - <unknown>
34: 0x7f32ec94d356 - <unknown>
35: 0x7f32ec94d4ed - <unknown>
36: 0x7f32fff3a477 - <unknown>
37: 0x7f32fff6be7c - <unknown>
38: 0x7f32fff71590 - <unknown>
39: 0x7f32fff3fff0 - <unknown>
40: 0x7f32fff4016d - <unknown>
41: 0x7f32ffd7e880 - <unknown>
42: 0x7f32ffd877c8 - <unknown>
43: 0x7f32ffd87973 - g_main_context_iteration
44: 0x7f32fffa402d - g_application_run
45: 0x560ff9a45dd9 - gio::application::ApplicationExtManual::run_with_args::h1ee0756279cc1afc
at /home/aleb/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/gio-0.21.1/src/application.rs:25:13
46: 0x560ff9a45fa9 - gio::application::ApplicationExtManual::run::h7b215ca94c0ad66d
at /home/aleb/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/gio-0.21.1/src/application.rs:17:9
47: 0x560ff99e9df8 - desktop_file_editor::main::h5c1167c6ad094ff5
at /home/aleb/workspace/desktop-manager/src/main.rs:34:5
48: 0x560ff9b9a21b - core::ops::function::FnOnce::call_once::hd9372ad5f9eeb22c
at /home/aleb/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ops/function.rs:250:5
49: 0x560ff9bb4fbe - std::sys::backtrace::__rust_begin_short_backtrace::h9157358bdc13aa96
at /home/aleb/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/sys/backtrace.rs:152:18
50: 0x560ff9b41c31 - std::rt::lang_start::{{closure}}::h60f876af9a835986
at /home/aleb/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/rt.rs:199:18
51: 0x560ffa337c44 - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::hb4b7cf0559a1a53b
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/core/src/ops/function.rs:284:13
52: 0x560ffa337c44 - std::panicking::try::do_call::h8e6004e979ada7de
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:589:40
53: 0x560ffa337c44 - std::panicking::try::hc44a0c902e55fa8c
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:552:19
54: 0x560ffa337c44 - std::panic::catch_unwind::h6a5f1ccd4faaed9e
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panic.rs:359:14
55: 0x560ffa337c44 - std::rt::lang_start_internal::{{closure}}::h40fd26f9e7cfe6a7
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/rt.rs:168:24
56: 0x560ffa337c44 - std::panicking::try::do_call::h047dd894cf3f6fd1
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:589:40
57: 0x560ffa337c44 - std::panicking::try::h921841e1eaed56ce
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panicking.rs:552:19
58: 0x560ffa337c44 - std::panic::catch_unwind::h108064a50ee785ec
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/panic.rs:359:14
59: 0x560ffa337c44 - std::rt::lang_start_internal::ha8ef919ae4984948
at /rustc/6b00bc3880198600130e1cf62b8f8a93494488cc/library/std/src/rt.rs:164:5
60: 0x560ff9b41c17 - std::rt::lang_start::hd50e03435b2650ce
at /home/aleb/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/rt.rs:198:5
61: 0x560ff99e9e5e - main
62: 0x7f32ffa36575 - __libc_start_call_main
63: 0x7f32ffa36628 - __libc_start_main_impl
64: 0x560ff99db1e5 - _start
65: 0x0 - <unknown>
Note
This bug seems very similar to #93 which should however be fixed.
Looking at the code and backtrace I think the problem is at line 226 in the File bindings where it tries to create a GString from the ETag pointer without checking that it is not null. The curious aspect is that this problem does not appear when not using the admin URI: files that do not require root permissions are written without panicking with the same exact call and same exact parameters (I always put None as the ETag parameter).
I would try fixing it myself but I'm not really familiar with any of this so I'm opening this issue. I'm not sure if just an explicit null check is all it takes to fix this.