diff options
| author | Konstantin Belousov <kib@FreeBSD.org> | 2026-06-08 01:22:51 +0000 |
|---|---|---|
| committer | Konstantin Belousov <kib@FreeBSD.org> | 2026-06-08 17:02:13 +0000 |
| commit | 0b269737f9ca057826a6c9376c2474b1ae5bc91c (patch) | |
| tree | dcb3aa8a1da7d7b13a214f43ab6603dd36b42d33 | |
| parent | 256fa87c9fc31d67c3da27dd1aac0c42db3dcf41 (diff) | |
imgact_elf: handle unaligned phdrs
Althought non-compliant, there are binaries which have the phdrs placed
unaligned in the image. Since we have the code to allocate memory for
off-page phdrs, the same code path can be used to handle unaligned
phdrs.
Relax the requirement for both the activated image and interpreter.
PR: 295629
Reviewed by: emaste, markj, olce
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D57498
| -rw-r--r-- | sys/kern/imgact_elf.c | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c index b889c4a14866..46908f01097b 100644 --- a/sys/kern/imgact_elf.c +++ b/sys/kern/imgact_elf.c @@ -858,12 +858,12 @@ __elfN(load_file)(struct thread *td, const char *file, u_long *addr, goto fail; } - if (!aligned(imgp->image_header + hdr->e_phoff, Elf_Addr) || - hdr->e_phnum > __elfN(phnums)) { + if (hdr->e_phnum > __elfN(phnums)) { error = ENOEXEC; goto fail; } - if (__elfN(phdr_in_zero_page)(hdr)) { + if (__elfN(phdr_in_zero_page)(hdr) && + aligned(imgp->image_header + hdr->e_phoff, Elf_Addr)) { phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); } else { VOP_UNLOCK(imgp->vp); @@ -1157,10 +1157,6 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp) free_interp = false; m_phdrs = NULL; - if (!aligned(imgp->image_header + hdr->e_phoff, Elf_Addr)) { - uprintf("Unaligned program headers\n"); - return (ENOEXEC); - } if (hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize < hdr->e_phoff) { uprintf("PHDRS wrap\n"); return (ENOEXEC); @@ -1170,7 +1166,8 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp) hdr->e_phnum, __elfN(phnums)); return (ENOEXEC); } - if (__elfN(phdr_in_zero_page)(hdr)) { + if (__elfN(phdr_in_zero_page)(hdr) && + aligned(imgp->image_header + hdr->e_phoff, Elf_Addr)) { phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); } else { VOP_UNLOCK(imgp->vp); |