lkml.org 
[lkml]   [2013]   [Mar]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH v2 01/20] vmcore: refer to e_phoff member explicitly
    于 2013年03月02日 16:35, HATAYAMA Daisuke 写道:
    > Code around /proc/vmcore currently assumes program header table is
    > next to ELF header. But future change can break the assumption on
    > kexec-tools and the 1st kernel. To avoid worst case, now refer to
    > e_phoff member that indicates position of program header table in
    > file-offset.

    Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>

    >
    > Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
    > ---
    >
    > fs/proc/vmcore.c | 40 ++++++++++++++++++++--------------------
    > 1 files changed, 20 insertions(+), 20 deletions(-)
    >
    > diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
    > index b870f74..abf4f01 100644
    > --- a/fs/proc/vmcore.c
    > +++ b/fs/proc/vmcore.c
    > @@ -221,8 +221,8 @@ static u64 __init get_vmcore_size_elf64(char *elfptr)
    > Elf64_Phdr *phdr_ptr;
    >
    > ehdr_ptr = (Elf64_Ehdr *)elfptr;
    > - phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
    > - size = sizeof(Elf64_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr));
    > + phdr_ptr = (Elf64_Phdr*)(elfptr + ehdr_ptr->e_phoff);
    > + size = ehdr_ptr->e_phoff + ((ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr));
    > for (i = 0; i < ehdr_ptr->e_phnum; i++) {
    > size += phdr_ptr->p_memsz;
    > phdr_ptr++;
    > @@ -238,8 +238,8 @@ static u64 __init get_vmcore_size_elf32(char *elfptr)
    > Elf32_Phdr *phdr_ptr;
    >
    > ehdr_ptr = (Elf32_Ehdr *)elfptr;
    > - phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
    > - size = sizeof(Elf32_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr));
    > + phdr_ptr = (Elf32_Phdr*)(elfptr + ehdr_ptr->e_phoff);
    > + size = ehdr_ptr->e_phoff + ((ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr));
    > for (i = 0; i < ehdr_ptr->e_phnum; i++) {
    > size += phdr_ptr->p_memsz;
    > phdr_ptr++;
    > @@ -259,7 +259,7 @@ static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
    > u64 phdr_sz = 0, note_off;
    >
    > ehdr_ptr = (Elf64_Ehdr *)elfptr;
    > - phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
    > + phdr_ptr = (Elf64_Phdr*)(elfptr + ehdr_ptr->e_phoff);
    > for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
    > int j;
    > void *notes_section;
    > @@ -305,7 +305,7 @@ static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
    > /* Prepare merged PT_NOTE program header. */
    > phdr.p_type = PT_NOTE;
    > phdr.p_flags = 0;
    > - note_off = sizeof(Elf64_Ehdr) +
    > + note_off = ehdr_ptr->e_phoff +
    > (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr);
    > phdr.p_offset = note_off;
    > phdr.p_vaddr = phdr.p_paddr = 0;
    > @@ -313,14 +313,14 @@ static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
    > phdr.p_align = 0;
    >
    > /* Add merged PT_NOTE program header*/
    > - tmp = elfptr + sizeof(Elf64_Ehdr);
    > + tmp = elfptr + ehdr_ptr->e_phoff;
    > memcpy(tmp, &phdr, sizeof(phdr));
    > tmp += sizeof(phdr);
    >
    > /* Remove unwanted PT_NOTE program headers. */
    > i = (nr_ptnote - 1) * sizeof(Elf64_Phdr);
    > *elfsz = *elfsz - i;
    > - memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr)));
    > + memmove(tmp, tmp+i, ((*elfsz)-ehdr_ptr->e_phoff-sizeof(Elf64_Phdr)));
    >
    > /* Modify e_phnum to reflect merged headers. */
    > ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
    > @@ -340,7 +340,7 @@ static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
    > u64 phdr_sz = 0, note_off;
    >
    > ehdr_ptr = (Elf32_Ehdr *)elfptr;
    > - phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
    > + phdr_ptr = (Elf32_Phdr*)(elfptr + ehdr_ptr->e_phoff);
    > for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
    > int j;
    > void *notes_section;
    > @@ -386,7 +386,7 @@ static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
    > /* Prepare merged PT_NOTE program header. */
    > phdr.p_type = PT_NOTE;
    > phdr.p_flags = 0;
    > - note_off = sizeof(Elf32_Ehdr) +
    > + note_off = ehdr_ptr->e_phoff +
    > (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr);
    > phdr.p_offset = note_off;
    > phdr.p_vaddr = phdr.p_paddr = 0;
    > @@ -394,14 +394,14 @@ static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
    > phdr.p_align = 0;
    >
    > /* Add merged PT_NOTE program header*/
    > - tmp = elfptr + sizeof(Elf32_Ehdr);
    > + tmp = elfptr + ehdr_ptr->e_phoff;
    > memcpy(tmp, &phdr, sizeof(phdr));
    > tmp += sizeof(phdr);
    >
    > /* Remove unwanted PT_NOTE program headers. */
    > i = (nr_ptnote - 1) * sizeof(Elf32_Phdr);
    > *elfsz = *elfsz - i;
    > - memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr)));
    > + memmove(tmp, tmp+i, ((*elfsz)-ehdr_ptr->e_phoff-sizeof(Elf32_Phdr)));
    >
    > /* Modify e_phnum to reflect merged headers. */
    > ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
    > @@ -422,10 +422,10 @@ static int __init process_ptload_program_headers_elf64(char *elfptr,
    > struct vmcore *new;
    >
    > ehdr_ptr = (Elf64_Ehdr *)elfptr;
    > - phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */
    > + phdr_ptr = (Elf64_Phdr*)(elfptr + ehdr_ptr->e_phoff); /* PT_NOTE hdr */
    >
    > /* First program header is PT_NOTE header. */
    > - vmcore_off = sizeof(Elf64_Ehdr) +
    > + vmcore_off = ehdr_ptr->e_phoff +
    > (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr) +
    > phdr_ptr->p_memsz; /* Note sections */
    >
    > @@ -459,10 +459,10 @@ static int __init process_ptload_program_headers_elf32(char *elfptr,
    > struct vmcore *new;
    >
    > ehdr_ptr = (Elf32_Ehdr *)elfptr;
    > - phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */
    > + phdr_ptr = (Elf32_Phdr*)(elfptr + ehdr_ptr->e_phoff); /* PT_NOTE hdr */
    >
    > /* First program header is PT_NOTE header. */
    > - vmcore_off = sizeof(Elf32_Ehdr) +
    > + vmcore_off = ehdr_ptr->e_phoff +
    > (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr) +
    > phdr_ptr->p_memsz; /* Note sections */
    >
    > @@ -496,7 +496,7 @@ static void __init set_vmcore_list_offsets_elf64(char *elfptr,
    > ehdr_ptr = (Elf64_Ehdr *)elfptr;
    >
    > /* Skip Elf header and program headers. */
    > - vmcore_off = sizeof(Elf64_Ehdr) +
    > + vmcore_off = ehdr_ptr->e_phoff +
    > (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr);
    >
    > list_for_each_entry(m, vc_list, list) {
    > @@ -516,7 +516,7 @@ static void __init set_vmcore_list_offsets_elf32(char *elfptr,
    > ehdr_ptr = (Elf32_Ehdr *)elfptr;
    >
    > /* Skip Elf header and program headers. */
    > - vmcore_off = sizeof(Elf32_Ehdr) +
    > + vmcore_off = ehdr_ptr->e_phoff +
    > (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr);
    >
    > list_for_each_entry(m, vc_list, list) {
    > @@ -553,7 +553,7 @@ static int __init parse_crash_elf64_headers(void)
    > }
    >
    > /* Read in all elf headers. */
    > - elfcorebuf_sz = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr);
    > + elfcorebuf_sz = ehdr.e_phoff + ehdr.e_phnum * sizeof(Elf64_Phdr);
    > elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
    > if (!elfcorebuf)
    > return -ENOMEM;
    > @@ -608,7 +608,7 @@ static int __init parse_crash_elf32_headers(void)
    > }
    >
    > /* Read in all elf headers. */
    > - elfcorebuf_sz = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr);
    > + elfcorebuf_sz = ehdr.e_phoff + ehdr.e_phnum * sizeof(Elf32_Phdr);
    > elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
    > if (!elfcorebuf)
    > return -ENOMEM;
    >
    >
    > _______________________________________________
    > kexec mailing list
    > kexec@lists.infradead.org
    > http://lists.infradead.org/mailman/listinfo/kexec
    >

    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2013-03-05 09:21    [W:2.932 / U:0.828 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site