diff options
author | Alexey Dobriyan <adobriyan@gmail.com> | 2020-01-30 22:17:04 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-01-31 10:30:41 -0800 |
commit | 225a3f53e7fc7ae9e57d336d712cadae62c39516 (patch) | |
tree | 41c871ca58564bb291040bad02b4e4d08ce38039 | |
parent | 18676ffcee596079037b1767e4efe38b06f05eb8 (diff) |
fs/binfmt_elf.c: coredump: allocate core ELF header on stack
Comment says ELF header is "too large to be on stack". 64 bytes on
64-bit is not large by any means.
Link: http://lkml.kernel.org/r/20191222143850.GA24341@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | fs/binfmt_elf.c | 16 |
1 files changed, 5 insertions, 11 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index e79e5a7216bd..6bf11c1d3b0f 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -2186,7 +2186,7 @@ static int elf_core_dump(struct coredump_params *cprm) int segs, i; size_t vma_data_size = 0; struct vm_area_struct *vma, *gate_vma; - struct elfhdr *elf = NULL; + struct elfhdr elf; loff_t offset = 0, dataoff; struct elf_note_info info = { }; struct elf_phdr *phdr4note = NULL; @@ -2207,10 +2207,6 @@ static int elf_core_dump(struct coredump_params *cprm) * exists while dumping the mm->vm_next areas to the core file. */ - /* alloc memory for large data structures: too large to be on stack */ - elf = kmalloc(sizeof(*elf), GFP_KERNEL); - if (!elf) - goto out; /* * The number of segs are recored into ELF header as 16bit value. * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here. @@ -2234,7 +2230,7 @@ static int elf_core_dump(struct coredump_params *cprm) * Collect all the non-memory information about the process for the * notes. This also sets up the file header. */ - if (!fill_note_info(elf, e_phnum, &info, cprm->siginfo, cprm->regs)) + if (!fill_note_info(&elf, e_phnum, &info, cprm->siginfo, cprm->regs)) goto cleanup; has_dumped = 1; @@ -2242,7 +2238,7 @@ static int elf_core_dump(struct coredump_params *cprm) fs = get_fs(); set_fs(KERNEL_DS); - offset += sizeof(*elf); /* Elf header */ + offset += sizeof(elf); /* Elf header */ offset += segs * sizeof(struct elf_phdr); /* Program headers */ /* Write notes phdr entry */ @@ -2285,12 +2281,12 @@ static int elf_core_dump(struct coredump_params *cprm) shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL); if (!shdr4extnum) goto end_coredump; - fill_extnum_info(elf, shdr4extnum, e_shoff, segs); + fill_extnum_info(&elf, shdr4extnum, e_shoff, segs); } offset = dataoff; - if (!dump_emit(cprm, elf, sizeof(*elf))) + if (!dump_emit(cprm, &elf, sizeof(elf))) goto end_coredump; if (!dump_emit(cprm, phdr4note, sizeof(*phdr4note))) @@ -2374,8 +2370,6 @@ cleanup: kfree(shdr4extnum); kvfree(vma_filesz); kfree(phdr4note); - kfree(elf); -out: return has_dumped; } |