Commit 5830f208 authored Jun 16, 2021 by Peter Zijlstra Committed by Sasha Levin Jun 30, 2021

recordmcount: Correct st_shndx handling

[ Upstream commit fb780761e7bd9f2e94f5b9a296ead6b35b944206 ]

One should only use st_shndx when >SHN_UNDEF and <SHN_LORESERVE. When
SHN_XINDEX, then use .symtab_shndx. Otherwise use 0.

This handles the case: st_shndx >= SHN_LORESERVE && st_shndx != SHN_XINDEX.

Link: https://lore.kernel.org/lkml/20210607023839.26387-1-mark-pk.tsai@mediatek.com/
Link: https://lkml.kernel.org/r/20210616154126.2794-1-mark-pk.tsai@mediatek.com



Reported-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
[handle endianness of sym->st_shndx]
Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 70866199

scripts/recordmcount.h

+10 −5

Original line number	Diff line number	Diff line
		@@ -192,17 +192,22 @@ static unsigned int get_symindex(Elf_Sym const sym, Elf32_Word const symtab,
		Elf32_Word const *symtab_shndx)
		{
		unsigned long offset;
		unsigned short shndx = w2(sym->st_shndx);
		int index;

		if (sym->st_shndx != SHN_XINDEX)
		return w2(sym->st_shndx);
		if (shndx > SHN_UNDEF && shndx < SHN_LORESERVE)
		return shndx;

		if (shndx == SHN_XINDEX) {
		offset = (unsigned long)sym - (unsigned long)symtab;
		index = offset / sizeof(*sym);

		return w(symtab_shndx[index]);
		}

		return 0;
		}

		static unsigned int get_shnum(Elf_Ehdr const ehdr, Elf_Shdr const shdr0)
		{
		if (shdr0 && !ehdr->e_shnum)