This is a note to let you know that I've just added the patch titled
modpost: do not make find_tosym() return NULL
to the 6.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
modpost-do-not-make-find_tosym-return-null.patch
and it can be found in the queue-6.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 5ede8130b2ce0d7e24650e47456e6d1d880b3f10
Author: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Date: Sat Mar 23 20:45:11 2024 +0900
modpost: do not make find_tosym() return NULL
[ 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>
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 267b9a0a3abcd..6568f8177e392 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -1007,6 +1007,8 @@ 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;
@@ -1015,8 +1017,9 @@ 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)
