Re: [PATCH][RFC] pseudo: intercept syscall() and return ENOTSUP for renameat2

[Richard Purdie <richard.purdie@linuxfoundation.org>]

Just to report back, I've tried testing an earlier version of pseudo
master with the path changes reverted and current master. With both I'm
seeing librsvg fail during do_install with a segfault (you have to
remove the 2> /dev/null to see it).

I'm seeing multiple entries in the host's dmesg:

[180364.269879] glib-compile-re[38258]: segfault at 0 ip           (null) sp 00007ffffaafbf78 error 14 in glib-compile-resources[55abc201b000+9000]
[180376.499904] glib-compile-re[46860]: segfault at 0 ip           (null) sp 00007ffd3b10f2c8 error 14 in glib-compile-resources[55b2cb528000+9000]
[180376.612404] glib-compile-re[46862]: segfault at 0 ip           (null) sp 00007fff612977f8 error 14 in glib-compile-resources[55ad08797000+9000]
[180376.726317] glib-compile-re[46864]: segfault at 0 ip           (null) sp 00007ffdce018928 error 14 in glib-compile-resources[5610851ec000+9000]
[180376.836705] glib-compile-re[46866]: segfault at 0 ip           (null) sp 00007ffc586fdda8 error 14 in glib-compile-resources[562f38dfc000+9000]
[180603.294668] gdk-pixbuf-quer[51620]: segfault at 0 ip           (null) sp 00007ffce7947fe8 error 14 in gdk-pixbuf-query-loaders.real[55b88bb7f000+2000]
[185206.227285] gdk-pixbuf-quer[51885]: segfault at 0 ip           (null) sp 00007ffe6393ae28 error 14 in gdk-pixbuf-query-loaders.real[556db9ae3000+2000]
[186523.735264] gdk-pixbuf-quer[70272]: segfault at 0 ip           (null) sp 00007fff6a855808 error 14 in gdk-pixbuf-query-loaders.real[55ec4e8fd000+2000]

I believe that libglib-2.0 does use syscall() for something and that
the above programs are calling into it and faulting.

Its likely possible to reproduce this outside of a build by running
make install from librsvg under pseudo.

If I take master and revert 778abd3686fb7c419e9016fdd9e93819405d52aa fr
om pseudo, it no longer segfaults.

So something is not working correctly with the intercept sadly.

Cheers,

Richard