This is the mail archive of the
gdb-prs@sourceware.org
mailing list for the GDB project.
[Bug gdb/23326] make_output_phdrs mishandles inaccessible sections
- From: "simon.marchi at ericsson dot com" <sourceware-bugzilla at sourceware dot org>
- To: gdb-prs at sourceware dot org
- Date: Thu, 28 Jun 2018 14:57:12 +0000
- Subject: [Bug gdb/23326] make_output_phdrs mishandles inaccessible sections
- Auto-submitted: auto-generated
- References: <bug-23326-4717@http.sourceware.org/bugzilla/>
https://sourceware.org/bugzilla/show_bug.cgi?id=23326
Simon Marchi <simon.marchi at ericsson dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |simon.marchi at ericsson dot com
--- Comment #1 from Simon Marchi <simon.marchi at ericsson dot com> ---
GDB takes the mapping info from /proc/<pid>/smaps, which contains the RWX
information. So it should be possible to use that information to conditionally
put the PF_R flag.
7f07cf9a0000-7f07cfb60000 r-xp 00000000 fd:01 395798
/lib/x86_64-linux-gnu/libc-2.23.so
Size: 1792 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
Rss: 1088 kB
Pss: 16 kB
Shared_Clean: 1088 kB
Shared_Dirty: 0 kB
Private_Clean: 0 kB
Private_Dirty: 0 kB
Referenced: 1088 kB
Anonymous: 0 kB
LazyFree: 0 kB
AnonHugePages: 0 kB
ShmemPmdMapped: 0 kB
Shared_Hugetlb: 0 kB
Private_Hugetlb: 0 kB
Swap: 0 kB
SwapPss: 0 kB
Locked: 16 kB
VmFlags: rd ex mr mw me sd
7f07cfb60000-7f07cfd60000 ---p 001c0000 fd:01 395798
/lib/x86_64-linux-gnu/libc-2.23.so
Size: 2048 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
Rss: 0 kB
Pss: 0 kB
Shared_Clean: 0 kB
Shared_Dirty: 0 kB
Private_Clean: 0 kB
Private_Dirty: 0 kB
Referenced: 0 kB
Anonymous: 0 kB
LazyFree: 0 kB
AnonHugePages: 0 kB
ShmemPmdMapped: 0 kB
Shared_Hugetlb: 0 kB
Private_Hugetlb: 0 kB
Swap: 0 kB
SwapPss: 0 kB
Locked: 0 kB
VmFlags: mr mw me sd
The second section looks like the 2MB section you are talking about.
> This is a regression but I haven't checked how recent it is. Older versions of gdb correctly handled inaccessible sections by writing phdrs for inaccessible sections, with PF_R correctly turned off and no image in the core.
I tested with versions as old as 7.1 (from 2010) and all PH are readable.
--
You are receiving this mail because:
You are on the CC list for the bug.