diff mbox series

[v2] recordmcount: Correct st_shndx handling

Message ID 20210615064720.21950-1-mark-pk.tsai@mediatek.com (mailing list archive)
State New, archived
Headers show
Series [v2] recordmcount: Correct st_shndx handling | expand

Commit Message

Mark-PK Tsai June 15, 2021, 6:47 a.m. UTC
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.

Reported-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
---
 scripts/recordmcount.h | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

Comments

Steven Rostedt June 15, 2021, 3:42 p.m. UTC | #1
On Tue, 15 Jun 2021 14:47:20 +0800
Mark-PK Tsai <mark-pk.tsai@mediatek.com> wrote:

> 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.
> 
> Reported-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>

Please explain the two signed-off-by's above. If you are just tweaking
Peter's original patch, please add at the start:

From: Peter Zijlstra (Intel) <peterz@infradead.org>

And then just above your signed off by, add what you changed:

Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
[ Changed something ]
Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>

But state what you changed.

Thanks!

-- Steve
Mark-PK Tsai June 15, 2021, 4:32 p.m. UTC | #2
> On Tue, 15 Jun 2021 14:47:20 +0800
> Mark-PK Tsai <mark-pk.tsai@mediatek.com> wrote:
> 
> > 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.
> > 
> > Reported-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> > Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> 
> Please explain the two signed-off-by's above. If you are just tweaking
> Peter's original patch, please add at the start:
> 
> From: Peter Zijlstra (Intel) <peterz@infradead.org>
> 
> And then just above your signed off by, add what you changed:
> 
> Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> [ Changed something ]
> Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> 
> But state what you changed.
> 
> Thanks!
> 
> -- Steve

Sorry for messing up.
I've fixed it in v3.

Thanks for your comment.
Steven Rostedt June 15, 2021, 5:07 p.m. UTC | #3
On Wed, 16 Jun 2021 00:32:45 +0800
Mark-PK Tsai <mark-pk.tsai@mediatek.com> wrote:

> > On Tue, 15 Jun 2021 14:47:20 +0800
> > Mark-PK Tsai <mark-pk.tsai@mediatek.com> wrote:
> >   
> > > 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.
> > > 
> > > Reported-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> > > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > > Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> > > Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>  
> > 
> > Please explain the two signed-off-by's above. If you are just tweaking
> > Peter's original patch, please add at the start:
> > 
> > From: Peter Zijlstra (Intel) <peterz@infradead.org>
> > 
> > And then just above your signed off by, add what you changed:
> > 
> > Tested-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> > [ Changed something ]
> > Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
> > 
> > But state what you changed.
> > 
> > Thanks!
> > 
> > -- Steve  
> 
> Sorry for messing up.

No problem. It's a learning process.

> I've fixed it in v3.

Thanks,

-- Steve
diff mbox series

Patch

diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h
index f9b19524da11..ef9c3425f86b 100644
--- a/scripts/recordmcount.h
+++ b/scripts/recordmcount.h
@@ -194,13 +194,18 @@  static unsigned int get_symindex(Elf_Sym const *sym, Elf32_Word const *symtab,
 	unsigned long offset;
 	int index;
 
-	if (sym->st_shndx != SHN_XINDEX)
+	if (w2(sym->st_shndx) > SHN_UNDEF &&
+	    w2(sym->st_shndx) < SHN_LORESERVE)
 		return w2(sym->st_shndx);
 
-	offset = (unsigned long)sym - (unsigned long)symtab;
-	index = offset / sizeof(*sym);
+	if (w2(sym->st_shndx) == SHN_XINDEX) {
+		offset = (unsigned long)sym - (unsigned long)symtab;
+		index = offset / sizeof(*sym);
 
-	return w(symtab_shndx[index]);
+		return w(symtab_shndx[index]);
+	}
+
+	return 0;
 }
 
 static unsigned int get_shnum(Elf_Ehdr const *ehdr, Elf_Shdr const *shdr0)