diff options
| author | Yuxiao Zhang <yuxiaozhang@google.com> | 2023-06-27 13:25:41 -0700 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2023-08-17 15:18:24 -0700 |
| commit | 104fd0b5e948157f8e8ac88a20b46ba8641d4e95 (patch) | |
| tree | dd88e938e7515d17ef837a470b750599818143b8 /fs/pstore/ram.c | |
| parent | fe8c3623ab06603eb760444a032d426542212021 (diff) | |
pstore: Support record sizes larger than kmalloc() limit
Currently pstore record buffers are allocated using kmalloc() which has
a maximum size based on page size. If a large "pmsg-size" module
parameter is specified, pmsg will fail to copy the contents since
memdup_user() is limited to kmalloc() allocation sizes.
Since we don't need physically contiguous memory for any of the pstore
record buffers, use kvzalloc() to avoid such limitations in the core of
pstore and in the ram backend, and explicitly read from userspace using
vmemdup_user(). This also means that any other backends that want to
(or do already) support larger record sizes will Just Work now.
Signed-off-by: Yuxiao Zhang <yuxiaozhang@google.com>
Link: https://lore.kernel.org/r/20230627202540.881909-2-yuxiaozhang@google.com
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Diffstat (limited to 'fs/pstore/ram.c')
| -rw-r--r-- | fs/pstore/ram.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 2f625e1fa8d8..d36702c7ab3c 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -20,6 +20,7 @@ #include <linux/compiler.h> #include <linux/of.h> #include <linux/of_address.h> +#include <linux/mm.h> #include "internal.h" #include "ram_internal.h" @@ -268,7 +269,7 @@ static ssize_t ramoops_pstore_read(struct pstore_record *record) /* ECC correction notice */ record->ecc_notice_size = persistent_ram_ecc_string(prz, NULL, 0); - record->buf = kmalloc(size + record->ecc_notice_size + 1, GFP_KERNEL); + record->buf = kvzalloc(size + record->ecc_notice_size + 1, GFP_KERNEL); if (record->buf == NULL) { size = -ENOMEM; goto out; @@ -282,7 +283,7 @@ static ssize_t ramoops_pstore_read(struct pstore_record *record) out: if (free_prz) { - kfree(prz->old_log); + kvfree(prz->old_log); kfree(prz); } @@ -833,7 +834,7 @@ static int ramoops_probe(struct platform_device *pdev) */ if (cxt->pstore.flags & PSTORE_FLAGS_DMESG) { cxt->pstore.bufsize = cxt->dprzs[0]->buffer_size; - cxt->pstore.buf = kzalloc(cxt->pstore.bufsize, GFP_KERNEL); + cxt->pstore.buf = kvzalloc(cxt->pstore.bufsize, GFP_KERNEL); if (!cxt->pstore.buf) { pr_err("cannot allocate pstore crash dump buffer\n"); err = -ENOMEM; @@ -866,7 +867,7 @@ static int ramoops_probe(struct platform_device *pdev) return 0; fail_buf: - kfree(cxt->pstore.buf); + kvfree(cxt->pstore.buf); fail_clear: cxt->pstore.bufsize = 0; fail_init: @@ -881,7 +882,7 @@ static void ramoops_remove(struct platform_device *pdev) pstore_unregister(&cxt->pstore); - kfree(cxt->pstore.buf); + kvfree(cxt->pstore.buf); cxt->pstore.bufsize = 0; ramoops_free_przs(cxt); |