[Differential] D51188: dtrace: fix symbol address resolving

zldrobit_gmail.com created this revision.
zldrobit_gmail.com added a reviewer: DTrace.
zldrobit_gmail.com added a project: DTrace.
Herald added a subscriber: imp.
Herald added a reviewer: gnn.
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REVISION SUMMARY
  Dtrace assumes only **ELF** sections of type `SHT_PROGBITS` or `SHT_NOBITS` occupy memory space. However, sections with `SHF_ALLOC` flag also consume memory space. Moreover, the symbol address initialization skips symbols at the very beginning of a section.
  
  Fix: Check section flag for calculating section offset, and disable the skipping at the beginning of a section.
  
  PR: 288000

REPOSITORY
  rG FreeBSD src repository

REVISION DETAIL
  https://reviews.freebsd.org/D51188

AFFECTED FILES
  cddl/contrib/opensolaris/lib/libdtrace/common/dt_module.c

CHANGE DETAILS

diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_module.c b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_module.c
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_module.c
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_module.c
@@ -159,8 +159,7 @@
 		if (sym->st_name == 0 || sym->st_name >= ss_size)
 			continue; /* skip null or invalid names */
 
-		if (sym->st_value != 0 &&
-		    (ELF64_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size)) {
+		if (ELF64_ST_BIND(sym->st_info) != STB_LOCAL || sym->st_size) {
 			asrsv++; /* reserve space in the address map */
 #if defined(__FreeBSD__)
 			sym->st_value += (Elf_Addr) dmp->dm_reloc_offset;
@@ -1218,7 +1217,7 @@
 			continue; /* skip any malformed sections */
 		if (sh.sh_size == 0)
 			continue;
-		if (sh.sh_type == SHT_PROGBITS || sh.sh_type == SHT_NOBITS) {
+		if (sh.sh_flags & SHF_ALLOC) {
 			alignmask = sh.sh_addralign - 1;
 			mapbase += alignmask;
 			mapbase &= ~alignmask;



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