From: Mark Wielaard Date: Wed, 4 Oct 2017 18:52:53 +0000 (+0200) Subject: libelf: Don't error out when sanity checking e_shoff if scncnt is zero. X-Git-Tag: elfutils-0.171~116 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4f977868eab2ea196a44e9d96c9e777134411391;p=thirdparty%2Felfutils.git libelf: Don't error out when sanity checking e_shoff if scncnt is zero. We won't use the e_shoff value in that case because we will set elf->state.elf[64|32].scns.cnt to zero to indicate not to read any section header data from the file. Signed-off-by: Mark Wielaard --- diff --git a/libelf/ChangeLog b/libelf/ChangeLog index 36b57dd1c..6aa1c6f55 100644 --- a/libelf/ChangeLog +++ b/libelf/ChangeLog @@ -1,3 +1,8 @@ +2017-10-04 Mark Wielaard + + * elf_begin.c (file_read_elf): Skip sanity checking e_shoff if scncnt + is zero, we won't use it then. + 2017-10-04 Mark Wielaard * libelfP.h: Add ELF_E_INVALID_ELF to error values enum. diff --git a/libelf/elf_begin.c b/libelf/elf_begin.c index 554527837..fb3a5b57f 100644 --- a/libelf/elf_begin.c +++ b/libelf/elf_begin.c @@ -373,7 +373,7 @@ file_read_elf (int fildes, void *map_address, unsigned char *e_ident, || (((uintptr_t) ((char *) ehdr + e_shoff) & (__alignof__ (Elf32_Shdr) - 1)) == 0))) { - if (unlikely (e_shoff >= maxsize) + if (unlikely (scncnt > 0 && e_shoff >= maxsize) || unlikely (maxsize - e_shoff < scncnt * sizeof (Elf32_Shdr))) { @@ -475,7 +475,7 @@ file_read_elf (int fildes, void *map_address, unsigned char *e_ident, || (((uintptr_t) ((char *) ehdr + e_shoff) & (__alignof__ (Elf64_Shdr) - 1)) == 0))) { - if (unlikely (e_shoff >= maxsize) + if (unlikely (scncnt > 0 && e_shoff >= maxsize) || unlikely (maxsize - e_shoff < scncnt * sizeof (Elf64_Shdr))) goto free_and_out;