6.8-stable review patch. If anyone has any objections, please let me know.
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From: Masahiro Yamada masahiroy@kernel.org
[ 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@kernel.org Signed-off-by: Masahiro Yamada masahiroy@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 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)