Re: [Crash-utility] [PATCH v2 0/2] Fix KASLR problem on sadump

Hi Takao, A couple things. Can you post against the current github sources, or at least use crash-7.2.0? I'm not sure what version you're working with: $ patch -p1 --dry-run < $dl/sadump_1.patch checking file defs.h Hunk #1 succeeded at 5629 (offset 7 lines). checking file x86_64.c Hunk #1 FAILED at 119. Hunk #2 succeeded at 1998 (offset 34 lines). Hunk #3 succeeded at 2016 (offset 34 lines). Hunk #4 succeeded at 2030 (offset 34 lines). Hunk #5 succeeded at 2086 (offset 34 lines). 1 out of 5 hunks FAILED $ patch -p1 --dry-run < $dl/sadump_2.patch checking file defs.h Hunk #1 succeeded at 2590 (offset 5 lines). Hunk #2 succeeded at 6312 (offset 47 lines). checking file sadump.c checking file sadump.h checking file symbols.c Hunk #3 succeeded at 12262 (offset 10 lines). $ It was easy enough to address the FAILED segment above, but there are a few issues with the sadump.c patch: $ make warn ... [ cut ] ... cc -c -g -DX86_64 -DLZO -DSNAPPY -DGDB_7_6 sadump.c -Wall -O2 -Wstrict-prototypes -Wmissing-prototypes -fstack-protector -Wformat-security sadump.c:1911:1: warning: no previous prototype for ‘get_kaslr_offset_from_vmcoreinfo’ [-Wmissing-prototypes] get_kaslr_offset_from_vmcoreinfo(ulong cr3, ulong orig_kaslr_offset, ^ sadump.c: In function ‘sadump_calc_kaslr_offset’: sadump.c:2088:38: warning: ‘scs.Cr3’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (get_kaslr_offset_from_vmcoreinfo( ^ sadump.c:2044:40: warning: ‘scs.IdtLower’ may be used uninitialized in this function [-Wmaybe-uninitialized] idtr = ((uint64_t)scs.IdtUpper)<<32 | (uint64_t)scs.IdtLower; ^ sadump.c:2044:10: warning: ‘scs.IdtUpper’ may be used uninitialized in this function [-Wmaybe-uninitialized] idtr = ((uint64_t)scs.IdtUpper)<<32 | (uint64_t)scs.IdtLower; ... But more importantly, the sadump.c patch won't compile against the other architectures, because x86_64_kvtop_pagetable() only exists when crash is built for x86_64. Plus I don't particularly like the kvtop "pagetable" argument abstraction and new functions that you put in place in x86_64.c just for these 3 rather arcane calls from sadump.c. I suggest adding a new machdep->flags bit (USE_PT?) which could be temporarily set in sadump.c prior to each of the 3 calls that could be made to the generic kvtop() function. Then in x86_64_kvtop(), check for the new machdep->flag as opposed to the "use_pagetable" argument. It may even be possible to use SADUMP() along with some other existing flag instead of creating a new one. But please just avoid creating the new functions in x86_64.c. Thanks, Dave ----- Original Message -----