With lld-generated binaries the first PT_LOAD will usually be a read-only
segment unless you pass --no-rosegment. For those binaries the textsize is
determined by the next PT_LOAD. To allow both LLD and bfd 2.17 binaries to
be parsed correctly use the end of the last PT_LOAD that is marked as
executable instead.
Details
Details
- Reviewers
kib emaste jhb brooks - Commits
- rS339876: rtld: set obj->textsize correctly
I noticed that the value was wrong while adding some debug prints for some rtld changes for CHERI binaries.
obj->textsize only seems to be used by PPC so the effect is untested. However, the value before was definitely wrong and the new result matches the phdrs.
Diff Detail
Diff Detail
- Repository
- rS FreeBSD src repository - subversion
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Don't you need a similar fix for the map_object.c ? There we unconditionally use segment zero.
I believe that ppc/ppc64 would be fine with the patch, since obj->textsize is used to limit the range to flush icache. With the increase of the textsize after the patch, we would only flush more.
| libexec/rtld-elf/rtld.c | ||
|---|---|---|
| 1487 ↗ | (On Diff #47910) | sys/param.h MAX() will evaluate the arguments twice, do we have a better min/max macro that I can use here? |
| libexec/rtld-elf/rtld.c | ||
|---|---|---|
| 1487 ↗ | (On Diff #47910) | Kernel has inlines like imax() in libkern.h, but I am not aware of anything like that for userspace. |
Comment Actions
Looks good to me too, and I think it's important for anything doing textrelocs on ppc.