On 07 Nov 2014, at 08:23, Riku Voipio wrote:
On Thu, Nov 06, 2014 at 01:43:13PM -0600, Tom Musta wrote:
When computing the upper address of a program segment, do not
subtract the
offset from the virtual address; instead compute the sum of the
virtual address
and the memory size.
Thanks, I'll test this and try to get it applied ASAP. Jonas, can you
have a look and provide your Acked-by/Tested-by ?
Good catch! Sorry for not noticing that. I've verified and the patched
version also still works with my ARM binary.
While looking at that, I noticed that the code under "#ifdef
CONFIG_USE_FDPIC" in linux-user/elfload.c at line 1858 may need a
similar adjustment as performed by my original patch. At least http://lxr.free-electrons.com/source/fs/binfmt_elf.c#L829
makes the offset adjustment both for binaries with and without a
"load_bias". I'm not sure what this is for (some uCLinux-specific
format?), nor do I have binaries that exercise this functionality, so
I can't/won't provide a patch for this.
Thanks,
Jonas
Signed-off-by: Tom Musta <tommu...@gmail.com>
---
Please include this patch in QEMU 2.2.
Commit a93934fecd4dffc9d4b452b670c9506be5dea30d injected a
regression of Linux
User Mode that I was able to detect on PowerPC 64 (but not x86). I
suspect that
large page size on the host has something to do with it. In any
case, that commit
adjusted the lower address of a program segment by the program
header's offset
field. However, it also inadvertantly adjusted the upper address
by the offset also.
linux-user/elfload.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 84123ba..e2596a4 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -1824,7 +1824,7 @@ static void load_elf_image(const char
*image_name, int image_fd,
if (a < loaddr) {
loaddr = a;
}
- a += phdr[i].p_memsz;
+ a = phdr[i].p_vaddr + phdr[i].p_memsz;
if (a > hiaddr) {
hiaddr = a;
}
--
1.7.1
