6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Masahiro Yamada <masahiroy@xxxxxxxxxx>
[ Upstream commit 1102f9f85bf66b1a7bd6a40afb40efbbe05dfc05 ]
As mentioned in commit 397586506c3d ("modpost: Add '.ltext' and
'.ltext.*' to TEXT_SECTIONS"), modpost can result in a segmentation
fault due to a NULL pointer dereference in default_mismatch_handler().
find_tosym() can return the original symbol pointer instead of NULL
if a better one is not found.
This fixes the reported segmentation fault.
Fixes: a23e7584ecf3 ("modpost: unify 'sym' and 'to' in default_mismatch_handler()")
Reported-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
scripts/mod/modpost.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 66589fb4e9aef..7d53942445d75 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -1052,6 +1052,8 @@ static Elf_Sym *find_fromsym(struct elf_info *elf, Elf_Addr addr,
static Elf_Sym *find_tosym(struct elf_info *elf, Elf_Addr addr, Elf_Sym *sym)
{
+ Elf_Sym *new_sym;
+
/* If the supplied symbol has a valid name, return it */
if (is_valid_name(elf, sym))
return sym;
@@ -1060,8 +1062,9 @@ static Elf_Sym *find_tosym(struct elf_info *elf, Elf_Addr addr, Elf_Sym *sym)
* Strive to find a better symbol name, but the resulting name may not
* match the symbol referenced in the original code.
*/
- return symsearch_find_nearest(elf, addr, get_secindex(elf, sym),
- true, 20);
+ new_sym = symsearch_find_nearest(elf, addr, get_secindex(elf, sym),
+ true, 20);
+ return new_sym ? new_sym : sym;
}
static bool is_executable_section(struct elf_info *elf, unsigned int secndx)
--
2.43.0
