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From: "mail@felix-potthast.de" <sourceware-bugzilla@sourceware.org> To: glibc-bugs@sourceware.org Subject: [Bug dynamic-link/31663] New: Stack not aligned at _start when calling ld.so explicitly Date: Fri, 19 Apr 2024 22:35:06 +0000 [thread overview] Message-ID: <bug-31663-131@http.sourceware.org/bugzilla/> (raw) https://sourceware.org/bugzilla/show_bug.cgi?id=31663 Bug ID: 31663 Summary: Stack not aligned at _start when calling ld.so explicitly Product: glibc Version: 2.35 Status: UNCONFIRMED Severity: normal Priority: P2 Component: dynamic-link Assignee: unassigned at sourceware dot org Reporter: mail@felix-potthast.de Target Milestone: --- Up to glibc version 2.35 the stack is not 16-byte aligned when the process is entered at _start when ld.so was called explicitly. The x86-64 SYS V ABI explicitly states it has to be aligned at that point, though. It also works fine when ld.so is invoked as elf interpreter. This doesn't result in any issue most of the time because the stack is aligned between _start and main in `sysdeps/x86_64/start.S`, for legacy reasons probably. I think the right place to do this alignment is at the end of ld.so. I attached a simple example that can be build with `gcc -nostartfiles test.S -o test`. It runs fine when running `./test` but segfaults when running with `/lib64/ld-linux-x86-64.so.2 ./test` due to missing stack alignment. -- You are receiving this mail because: You are on the CC list for the bug.
next reply other threads:[~2024-04-19 22:35 UTC|newest] Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top 2024-04-19 22:35 mail@felix-potthast.de [this message] 2024-04-19 22:38 ` [Bug dynamic-link/31663] " mail@felix-potthast.de 2024-04-20 7:03 ` schwab@linux-m68k.org
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