[Crash-utility] Re: [PATCH] fix eheader overflow

Hi Bruno, Thanks for the fix, LGTM, ack. Thanks, Tao Liu On Wed, Mar 25, 2026 at 2:55 PM Bruno Faccini <bfaccini(a)nvidia.com&gt; wrote: > > > crash-utility live session fails solid with a SEGV, where it seems > that with some (new ?) Kernels and configurations /proc/kcore > exposes a first “Note” program-header along with a big number of > other headers (particularly when direct-map area generated from > physical memory map have a lot of entries), causing eheader[] > overflow (a stack underflow in fact since it is an automatic > variable!) because the whole size exceeds MAX_KCORE_ELF_HEADER_SIZE. > This problem still occur with latest utility version, and the > following patch has been proven to fix. > > Signed-off-by: Bruno Faccini <bfaccini(a)nvidia.com&gt; > > diff --git a/netdump.c b/netdump.c > index 452ef72..7697613 100644 > --- a/netdump.c > +++ b/netdump.c > @@ -4664,7 +4664,12 @@ proc_kcore_init_32(FILE *fp, int kcore_fd) > clean_exit(1); > } > > - BCOPY(&eheader[0], &pkd->elf_header[0], pkd->header_size); > + if (read(fd, pkd->elf_header, pkd->header_size) != pkd->header_size) { > + sprintf(buf, "/proc/kcore: read"); > + perror(buf); > + goto bailout; > + } > + > pkd->notes32 = (Elf32_Phdr *)&pkd->elf_header[elf32->e_phoff]; > pkd->load32 = pkd->notes32 + 1; > pkd->flags |= KCORE_ELF32; > @@ -4738,7 +4743,12 @@ proc_kcore_init_64(FILE *fp, int kcore_fd) > clean_exit(1); > } > > - BCOPY(&eheader[0], &pkd->elf_header[0], pkd->header_size); > + if (read(fd, pkd->elf_header, pkd->header_size) != pkd->header_size) { > + sprintf(buf, "/proc/kcore: read"); > + perror(buf); > + goto bailout; > + } > + > pkd->notes64 = (Elf64_Phdr *)&pkd->elf_header[elf64->e_phoff]; > pkd->load64 = pkd->notes64 + 1; > pkd->flags |= KCORE_ELF64; > -- > Crash-utility mailing list -- devel(a)lists.crash-utility.osci.io > To unsubscribe send an email to devel-leave(a)lists.crash-utility.osci.io > https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/ > Contribution Guidelines: https://github.com/crash-utility/crash/wiki