From: Christoph Hellwig <hch@lst.de>
To: Andrew Morton <akpm@linux-foundation.org>,
Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>,
linuxppc-dev@lists.ozlabs.org, x86@kernel.org,
Oleg Nesterov <oleg@redhat.com>,
linux-kernel@vger.kernel.org,
"Eric W . Biederman" <ebiederm@xmission.com>,
linux-fsdevel@vger.kernel.org,
Linus Torvalds <torvalds@linux-foundation.org>,
Jeremy Kerr <jk@ozlabs.org>
Subject: [PATCH 7/7] binfmt_elf_fdpic: remove the set_fs(KERNEL_DS) in elf_fdpic_core_dump
Date: Tue, 5 May 2020 12:12:56 +0200 [thread overview]
Message-ID: <20200505101256.3121270-8-hch@lst.de> (raw)
In-Reply-To: <20200505101256.3121270-1-hch@lst.de>
There is no logic in elf_fdpic_core_dump itself or in the various arch
helpers called from it which use uaccess routines on kernel pointers
except for the file writes thate are nicely encapsulated by using
__kernel_write in dump_emit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/binfmt_elf_fdpic.c | 21 +++++++--------------
1 file changed, 7 insertions(+), 14 deletions(-)
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index 240f666635437..d9501a86cec97 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -1549,7 +1549,6 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
{
#define NUM_NOTES 6
int has_dumped = 0;
- mm_segment_t fs;
int segs;
int i;
struct vm_area_struct *vma;
@@ -1589,31 +1588,31 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
/* alloc memory for large data structures: too large to be on stack */
elf = kmalloc(sizeof(*elf), GFP_KERNEL);
if (!elf)
- goto cleanup;
+ goto end_coredump;
prstatus = kzalloc(sizeof(*prstatus), GFP_KERNEL);
if (!prstatus)
- goto cleanup;
+ goto end_coredump;
psinfo = kmalloc(sizeof(*psinfo), GFP_KERNEL);
if (!psinfo)
- goto cleanup;
+ goto end_coredump;
notes = kmalloc_array(NUM_NOTES, sizeof(struct memelfnote),
GFP_KERNEL);
if (!notes)
- goto cleanup;
+ goto end_coredump;
fpu = kmalloc(sizeof(*fpu), GFP_KERNEL);
if (!fpu)
- goto cleanup;
+ goto end_coredump;
#ifdef ELF_CORE_COPY_XFPREGS
xfpu = kmalloc(sizeof(*xfpu), GFP_KERNEL);
if (!xfpu)
- goto cleanup;
+ goto end_coredump;
#endif
for (ct = current->mm->core_state->dumper.next;
ct; ct = ct->next) {
tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
if (!tmp)
- goto cleanup;
+ goto end_coredump;
tmp->thread = ct->task;
list_add(&tmp->list, &thread_list);
@@ -1678,9 +1677,6 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
"LINUX", ELF_CORE_XFPREG_TYPE, sizeof(*xfpu), xfpu);
#endif
- fs = get_fs();
- set_fs(KERNEL_DS);
-
offset += sizeof(*elf); /* Elf header */
offset += segs * sizeof(struct elf_phdr); /* Program headers */
@@ -1788,9 +1784,6 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
}
end_coredump:
- set_fs(fs);
-
-cleanup:
while (!list_empty(&thread_list)) {
struct list_head *tmp = thread_list.next;
list_del(tmp);
--
2.26.2
next prev parent reply other threads:[~2020-05-05 10:34 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-05 10:12 remove set_fs calls from the coredump code v6 Christoph Hellwig
2020-05-05 10:12 ` [PATCH 1/7] powerpc/spufs: fix copy_to_user while atomic Christoph Hellwig
2020-05-05 10:12 ` [PATCH 2/7] powerpc/spufs: stop using access_ok Christoph Hellwig
2020-05-05 10:12 ` [PATCH 3/7] powerpc/spufs: simplify spufs core dumping Christoph Hellwig
2020-05-05 10:12 ` [PATCH 4/7] signal: refactor copy_siginfo_to_user32 Christoph Hellwig
2020-05-05 10:12 ` [PATCH 5/7] binfmt_elf: remove the set_fs in fill_siginfo_note Christoph Hellwig
2020-05-05 10:12 ` [PATCH 6/7] binfmt_elf: remove the set_fs(KERNEL_DS) in elf_core_dump Christoph Hellwig
2020-05-05 10:12 ` Christoph Hellwig [this message]
2020-05-05 16:52 ` remove set_fs calls from the coredump code v6 Linus Torvalds
2020-05-05 20:28 ` Eric W. Biederman
2020-05-06 6:31 ` Christoph Hellwig
2020-05-06 15:44 ` Eric W. Biederman
2020-05-05 20:34 ` Al Viro
2020-05-05 20:42 ` Christoph Hellwig
2020-05-05 20:47 ` Al Viro
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