[HACKERS] [bug fix] ECPG app crashes due to SIGBUS on SPARC Solaris

[MauMau]

Hello,





[Problem]


The steps to reproduce the problem is:
1. ecpg sigbus.pgc

3. a.out



   var->value = *((char **) (var->pointer));


[Cause]
ecpg outputs the following line in the preprocessed source file:

{ ECPGdo(__LINE__, 0, 1, NULL, 0, ECPGst_normal, "fetch $0",
ECPGt_char,(cur),(long)4,(long)1,(4)*sizeof(char),
ECPGt_NO_INDICATOR, NULL , 0L, 0L, 0L, ECPGt_EOIT,
ECPGt_descriptor, (desc1), 0L, 0L, 0L,
ECPGt_NO_INDICATOR, NULL , 0L, 0L, 0L, ECPGt_EORT);}




[Fix]


   var->value = var->pointer;




Regards
MauMau

I encountered a bug of ECPG with PG 9.2.4, which probably exists in all releases. The attached patch is for 9.4. Could you review and backport this to at least 9.2 and later? The attached ECPG app crashes and dumps core with SIGBUS on Solaris for SPARC. I used Solaris 10, and Oracle Studio to compile the app for 64-bit build. The same app completes successfully on Linux and Windows for x86/x564. 2. cc -xtarget=generic64 -I<pgsql_dir>/include sigbus.c -L<pgsql_dir>/lib -lecpg When execting FETCH statement using an SQL descriptor, the app crashes at the following line in ECPGdo(), which is in src/interfaces/ecpg/ecpglib/execute.c: So, the above line is executed in ECPGdo(). On the other hand, desc1 is not aligned on 8-byte boundary. This unaligned access causes SIGBUS. Because desc1 is a char array, else block should be executed instead of the above path. Therefore, make ecpg pass SQL descriptor host variables to ECPGdo() with non-zero lengths.

ECPG_descriptor_crash.patch
Description: Binary data

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