Created attachment 52721 [details] output.txt is output of ASAN, and inf-recursion is the poc At commit `b8e92c571baed4e794bd62b7bf417fa8bbaf5c95` of `binutils-gdb`, the given poc can produces crash on `cxxfilt`: build2/binutils/cxxfilt < inf-recursion
Hello, It's already more than one month since my post, and the bug still exists at latest commit (e.i. e84412c6a3c3eed1a4eca5fe18f329bfa7efea40), so I would like to know why it is still `UNCONFIRMED`. Thanks.
The simplified PoC: $ echo _RYAbB2_ | ./binutils/cxxfilt Segmentation fault Root Cause Analysis: 1. In `rust_demangle_callback`, "_R" at beginning causes `rdm.version == 0`[1][2], so `demangle_path` in the else-branch is called[3] with `rdm.sym == "YAbB2_"`, with `rdm.next` field initialized to 0. 2. Next char 'Y' causes `demangle_type` to be called[4] in a switch-case branch, with `rdm.next == 1`. 3. Next char 'A' causes `demangle_type` to be called first[5] to consume char 'b', then `demangle_const` is called[6] with `rdm.next == 3`. 4. Next char 'B' is consumed[7], and "2_" is parsed as `integer_62`[8] to be value 3, and this vlaue is assigned to `rdm.next`, then `demangle_const` is called recursively[9]. However, currently the situation is `rdm.next == 3` again, which is exactly same as last call to `demangle_const`, and this causes infinite recursion. [1] https://github.com/bminor/binutils-gdb/blob/626d0e40e55c35a4f143b70def498734e8ed3c2a/libiberty/rust-demangle.c#L1356 [2] https://github.com/bminor/binutils-gdb/blob/626d0e40e55c35a4f143b70def498734e8ed3c2a/libiberty/rust-demangle.c#L1362 [3] https://github.com/bminor/binutils-gdb/blob/626d0e40e55c35a4f143b70def498734e8ed3c2a/libiberty/rust-demangle.c#L1453 [4] https://github.com/bminor/binutils-gdb/blob/626d0e40e55c35a4f143b70def498734e8ed3c2a/libiberty/rust-demangle.c#L759 [5] https://github.com/bminor/binutils-gdb/blob/626d0e40e55c35a4f143b70def498734e8ed3c2a/libiberty/rust-demangle.c#L934 [6] https://github.com/bminor/binutils-gdb/blob/626d0e40e55c35a4f143b70def498734e8ed3c2a/libiberty/rust-demangle.c#L938 [7] https://github.com/bminor/binutils-gdb/blob/626d0e40e55c35a4f143b70def498734e8ed3c2a/libiberty/rust-demangle.c#L1151 [8] https://github.com/bminor/binutils-gdb/blob/626d0e40e55c35a4f143b70def498734e8ed3c2a/libiberty/rust-demangle.c#L1153 [9] https://github.com/bminor/binutils-gdb/blob/626d0e40e55c35a4f143b70def498734e8ed3c2a/libiberty/rust-demangle.c#L1158 Possible Fix: The infinite recursion check added in this [commit](https://github.com/bminor/binutils-gdb/commit/f10f8617a302f45dae721eae0cd659911f03d864) should also be applied to `demangle_const`
Maybe a dup of PR 104435