On Wed, Jan 31, 2024 at 08:53:49AM +0100, Helge Deller wrote: > On 1/31/24 01:18, Ilya Leoshkevich wrote: > > Like TARGET_NR_setuid, TARGET_NR_setgroups should affect only the > > calling thread, and not the entire process. Therefore, implement it > > using a syscall, and not a libc call. > > > > Cc: qemu-sta...@nongnu.org > > Fixes: 19b84f3c35d7 ("added setgroups and getgroups syscalls") > > Signed-off-by: Ilya Leoshkevich <i...@linux.ibm.com> > > Patch seems ok, but just out of interest, how did you noticed? > > Helge
Our internal users are trying to emulate a larger app, and they were running into weird crashes between fork() and exec(). I had to implement syscall catchpoints (posted) and follow-fork-mode child (still needs a few cleanups before I can post it) to be able to debug it, and found it was dying here [1], and from there it was easy. [1] https://sourceware.org/git/?p=glibc.git;a=blob;f=nptl/nptl_setxid.c;h=4bfcfe41882d9b15b8090325bfdc9ceb5ab2693e;hb=36f2487f13e3540be9ee0fb51876b1da72176d3f#l25