diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-06 15:16:16 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-06 15:16:16 -0700 |
commit | 0fb3ca447ddabcfb8dc7e0f719955e500b170cbd (patch) | |
tree | 57e516541b7650149c468a9567152164b12c75e3 /fs | |
parent | 3940ee36a0565ea7fb848e3c798afe22efd0b90a (diff) | |
parent | f88baf68ebe5b2efced64725fd98548af9b8f510 (diff) |
Merge tag 'pstore-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull pstore updates from Kees Cook:
- Fix bug in module unloading
- Switch to always using spinlock over cmpxchg
- Explicitly define pstore backend's supported modes
- Remove bounce buffer from pmsg
- Switch to using memcpy_to/fromio()
- Error checking improvements
* tag 'pstore-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
ramoops: move spin_lock_init after kmalloc error checking
pstore/ram: Use memcpy_fromio() to save old buffer
pstore/ram: Use memcpy_toio instead of memcpy
pstore/pmsg: drop bounce buffer
pstore/ram: Set pstore flags dynamically
pstore: Split pstore fragile flags
pstore/core: drop cmpxchg based updates
pstore/ramoops: fixup driver removal
Diffstat (limited to 'fs')
-rw-r--r-- | fs/pstore/platform.c | 53 | ||||
-rw-r--r-- | fs/pstore/pmsg.c | 35 | ||||
-rw-r--r-- | fs/pstore/ram.c | 46 | ||||
-rw-r--r-- | fs/pstore/ram_core.c | 96 |
4 files changed, 142 insertions, 88 deletions
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 16ecca5b72d8..14984d902a99 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -623,6 +623,40 @@ static int pstore_write_compat(enum pstore_type_id type, size, psi); } +static int pstore_write_buf_user_compat(enum pstore_type_id type, + enum kmsg_dump_reason reason, + u64 *id, unsigned int part, + const char __user *buf, + bool compressed, size_t size, + struct pstore_info *psi) +{ + unsigned long flags = 0; + size_t i, bufsize = size; + long ret = 0; + + if (unlikely(!access_ok(VERIFY_READ, buf, size))) + return -EFAULT; + if (bufsize > psinfo->bufsize) + bufsize = psinfo->bufsize; + spin_lock_irqsave(&psinfo->buf_lock, flags); + for (i = 0; i < size; ) { + size_t c = min(size - i, bufsize); + + ret = __copy_from_user(psinfo->buf, buf + i, c); + if (unlikely(ret != 0)) { + ret = -EFAULT; + break; + } + ret = psi->write_buf(type, reason, id, part, psinfo->buf, + compressed, c, psi); + if (unlikely(ret < 0)) + break; + i += c; + } + spin_unlock_irqrestore(&psinfo->buf_lock, flags); + return unlikely(ret < 0) ? ret : size; +} + /* * platform specific persistent storage driver registers with * us here. If pstore is already mounted, call the platform @@ -645,6 +679,8 @@ int pstore_register(struct pstore_info *psi) if (!psi->write) psi->write = pstore_write_compat; + if (!psi->write_buf_user) + psi->write_buf_user = pstore_write_buf_user_compat; psinfo = psi; mutex_init(&psinfo->read_mutex); spin_unlock(&pstore_lock); @@ -659,13 +695,14 @@ int pstore_register(struct pstore_info *psi) if (pstore_is_mounted()) pstore_get_records(0); - pstore_register_kmsg(); - - if ((psi->flags & PSTORE_FLAGS_FRAGILE) == 0) { + if (psi->flags & PSTORE_FLAGS_DMESG) + pstore_register_kmsg(); + if (psi->flags & PSTORE_FLAGS_CONSOLE) pstore_register_console(); + if (psi->flags & PSTORE_FLAGS_FTRACE) pstore_register_ftrace(); + if (psi->flags & PSTORE_FLAGS_PMSG) pstore_register_pmsg(); - } if (pstore_update_ms >= 0) { pstore_timer.expires = jiffies + @@ -689,12 +726,14 @@ EXPORT_SYMBOL_GPL(pstore_register); void pstore_unregister(struct pstore_info *psi) { - if ((psi->flags & PSTORE_FLAGS_FRAGILE) == 0) { + if (psi->flags & PSTORE_FLAGS_PMSG) pstore_unregister_pmsg(); + if (psi->flags & PSTORE_FLAGS_FTRACE) pstore_unregister_ftrace(); + if (psi->flags & PSTORE_FLAGS_CONSOLE) pstore_unregister_console(); - } - pstore_unregister_kmsg(); + if (psi->flags & PSTORE_FLAGS_DMESG) + pstore_unregister_kmsg(); free_buf_for_compression(); diff --git a/fs/pstore/pmsg.c b/fs/pstore/pmsg.c index 7de20cd3797f..78f6176c020f 100644 --- a/fs/pstore/pmsg.c +++ b/fs/pstore/pmsg.c @@ -19,48 +19,25 @@ #include "internal.h" static DEFINE_MUTEX(pmsg_lock); -#define PMSG_MAX_BOUNCE_BUFFER_SIZE (2*PAGE_SIZE) static ssize_t write_pmsg(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - size_t i, buffer_size; - char *buffer; + u64 id; + int ret; if (!count) return 0; + /* check outside lock, page in any data. write_buf_user also checks */ if (!access_ok(VERIFY_READ, buf, count)) return -EFAULT; - buffer_size = count; - if (buffer_size > PMSG_MAX_BOUNCE_BUFFER_SIZE) - buffer_size = PMSG_MAX_BOUNCE_BUFFER_SIZE; - buffer = vmalloc(buffer_size); - if (!buffer) - return -ENOMEM; - mutex_lock(&pmsg_lock); - for (i = 0; i < count; ) { - size_t c = min(count - i, buffer_size); - u64 id; - long ret; - - ret = __copy_from_user(buffer, buf + i, c); - if (unlikely(ret != 0)) { - mutex_unlock(&pmsg_lock); - vfree(buffer); - return -EFAULT; - } - psinfo->write_buf(PSTORE_TYPE_PMSG, 0, &id, 0, buffer, 0, c, - psinfo); - - i += c; - } - + ret = psinfo->write_buf_user(PSTORE_TYPE_PMSG, 0, &id, 0, buf, 0, count, + psinfo); mutex_unlock(&pmsg_lock); - vfree(buffer); - return count; + return ret ? ret : count; } static const struct file_operations pmsg_fops = { diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 7a034d62cf8c..6ad831b9d1b8 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -331,6 +331,24 @@ static int notrace ramoops_pstore_write_buf(enum pstore_type_id type, return 0; } +static int notrace ramoops_pstore_write_buf_user(enum pstore_type_id type, + enum kmsg_dump_reason reason, + u64 *id, unsigned int part, + const char __user *buf, + bool compressed, size_t size, + struct pstore_info *psi) +{ + if (type == PSTORE_TYPE_PMSG) { + struct ramoops_context *cxt = psi->data; + + if (!cxt->mprz) + return -ENOMEM; + return persistent_ram_write_user(cxt->mprz, buf, size); + } + + return -EINVAL; +} + static int ramoops_pstore_erase(enum pstore_type_id type, u64 id, int count, struct timespec time, struct pstore_info *psi) { @@ -369,6 +387,7 @@ static struct ramoops_context oops_cxt = { .open = ramoops_pstore_open, .read = ramoops_pstore_read, .write_buf = ramoops_pstore_write_buf, + .write_buf_user = ramoops_pstore_write_buf_user, .erase = ramoops_pstore_erase, }, }; @@ -377,13 +396,14 @@ static void ramoops_free_przs(struct ramoops_context *cxt) { int i; - cxt->max_dump_cnt = 0; if (!cxt->przs) return; - for (i = 0; !IS_ERR_OR_NULL(cxt->przs[i]); i++) + for (i = 0; i < cxt->max_dump_cnt; i++) persistent_ram_free(cxt->przs[i]); + kfree(cxt->przs); + cxt->max_dump_cnt = 0; } static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt, @@ -408,7 +428,7 @@ static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt, GFP_KERNEL); if (!cxt->przs) { dev_err(dev, "failed to initialize a prz array for dumps\n"); - goto fail_prz; + goto fail_mem; } for (i = 0; i < cxt->max_dump_cnt; i++) { @@ -419,6 +439,11 @@ static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt, err = PTR_ERR(cxt->przs[i]); dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n", cxt->record_size, (unsigned long long)*paddr, err); + + while (i > 0) { + i--; + persistent_ram_free(cxt->przs[i]); + } goto fail_prz; } *paddr += cxt->record_size; @@ -426,7 +451,9 @@ static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt, return 0; fail_prz: - ramoops_free_przs(cxt); + kfree(cxt->przs); +fail_mem: + cxt->max_dump_cnt = 0; return err; } @@ -608,12 +635,20 @@ static int ramoops_probe(struct platform_device *pdev) cxt->pstore.bufsize = 1024; /* LOG_LINE_MAX */ cxt->pstore.bufsize = max(cxt->record_size, cxt->pstore.bufsize); cxt->pstore.buf = kmalloc(cxt->pstore.bufsize, GFP_KERNEL); - spin_lock_init(&cxt->pstore.buf_lock); if (!cxt->pstore.buf) { pr_err("cannot allocate pstore buffer\n"); err = -ENOMEM; goto fail_clear; } + spin_lock_init(&cxt->pstore.buf_lock); + + cxt->pstore.flags = PSTORE_FLAGS_DMESG; + if (cxt->console_size) + cxt->pstore.flags |= PSTORE_FLAGS_CONSOLE; + if (cxt->ftrace_size) + cxt->pstore.flags |= PSTORE_FLAGS_FTRACE; + if (cxt->pmsg_size) + cxt->pstore.flags |= PSTORE_FLAGS_PMSG; err = pstore_register(&cxt->pstore); if (err) { @@ -659,7 +694,6 @@ static int ramoops_remove(struct platform_device *pdev) struct ramoops_context *cxt = &oops_cxt; pstore_unregister(&cxt->pstore); - cxt->max_dump_cnt = 0; kfree(cxt->pstore.buf); cxt->pstore.bufsize = 0; diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c index 76c3f80efdfa..3975deec02f8 100644 --- a/fs/pstore/ram_core.c +++ b/fs/pstore/ram_core.c @@ -17,15 +17,16 @@ #include <linux/device.h> #include <linux/err.h> #include <linux/errno.h> -#include <linux/kernel.h> #include <linux/init.h> #include <linux/io.h> +#include <linux/kernel.h> #include <linux/list.h> #include <linux/memblock.h> +#include <linux/pstore_ram.h> #include <linux/rslib.h> #include <linux/slab.h> +#include <linux/uaccess.h> #include <linux/vmalloc.h> -#include <linux/pstore_ram.h> #include <asm/page.h> struct persistent_ram_buffer { @@ -47,43 +48,10 @@ static inline size_t buffer_start(struct persistent_ram_zone *prz) return atomic_read(&prz->buffer->start); } -/* increase and wrap the start pointer, returning the old value */ -static size_t buffer_start_add_atomic(struct persistent_ram_zone *prz, size_t a) -{ - int old; - int new; - - do { - old = atomic_read(&prz->buffer->start); - new = old + a; - while (unlikely(new >= prz->buffer_size)) - new -= prz->buffer_size; - } while (atomic_cmpxchg(&prz->buffer->start, old, new) != old); - - return old; -} - -/* increase the size counter until it hits the max size */ -static void buffer_size_add_atomic(struct persistent_ram_zone *prz, size_t a) -{ - size_t old; - size_t new; - - if (atomic_read(&prz->buffer->size) == prz->buffer_size) - return; - - do { - old = atomic_read(&prz->buffer->size); - new = old + a; - if (new > prz->buffer_size) - new = prz->buffer_size; - } while (atomic_cmpxchg(&prz->buffer->size, old, new) != old); -} - static DEFINE_RAW_SPINLOCK(buffer_lock); /* increase and wrap the start pointer, returning the old value */ -static size_t buffer_start_add_locked(struct persistent_ram_zone *prz, size_t a) +static size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a) { int old; int new; @@ -103,7 +71,7 @@ static size_t buffer_start_add_locked(struct persistent_ram_zone *prz, size_t a) } /* increase the size counter until it hits the max size */ -static void buffer_size_add_locked(struct persistent_ram_zone *prz, size_t a) +static void buffer_size_add(struct persistent_ram_zone *prz, size_t a) { size_t old; size_t new; @@ -124,9 +92,6 @@ exit: raw_spin_unlock_irqrestore(&buffer_lock, flags); } -static size_t (*buffer_start_add)(struct persistent_ram_zone *, size_t) = buffer_start_add_atomic; -static void (*buffer_size_add)(struct persistent_ram_zone *, size_t) = buffer_size_add_atomic; - static void notrace persistent_ram_encode_rs8(struct persistent_ram_zone *prz, uint8_t *data, size_t len, uint8_t *ecc) { @@ -299,10 +264,20 @@ static void notrace persistent_ram_update(struct persistent_ram_zone *prz, const void *s, unsigned int start, unsigned int count) { struct persistent_ram_buffer *buffer = prz->buffer; - memcpy(buffer->data + start, s, count); + memcpy_toio(buffer->data + start, s, count); persistent_ram_update_ecc(prz, start, count); } +static int notrace persistent_ram_update_user(struct persistent_ram_zone *prz, + const void __user *s, unsigned int start, unsigned int count) +{ + struct persistent_ram_buffer *buffer = prz->buffer; + int ret = unlikely(__copy_from_user(buffer->data + start, s, count)) ? + -EFAULT : 0; + persistent_ram_update_ecc(prz, start, count); + return ret; +} + void persistent_ram_save_old(struct persistent_ram_zone *prz) { struct persistent_ram_buffer *buffer = prz->buffer; @@ -322,8 +297,8 @@ void persistent_ram_save_old(struct persistent_ram_zone *prz) } prz->old_log_size = size; - memcpy(prz->old_log, &buffer->data[start], size - start); - memcpy(prz->old_log + size - start, &buffer->data[0], start); + memcpy_fromio(prz->old_log, &buffer->data[start], size - start); + memcpy_fromio(prz->old_log + size - start, &buffer->data[0], start); } int notrace persistent_ram_write(struct persistent_ram_zone *prz, @@ -356,6 +331,38 @@ int notrace persistent_ram_write(struct persistent_ram_zone *prz, return count; } +int notrace persistent_ram_write_user(struct persistent_ram_zone *prz, + const void __user *s, unsigned int count) +{ + int rem, ret = 0, c = count; + size_t start; + + if (unlikely(!access_ok(VERIFY_READ, s, count))) + return -EFAULT; + if (unlikely(c > prz->buffer_size)) { + s += c - prz->buffer_size; + c = prz->buffer_size; + } + + buffer_size_add(prz, c); + + start = buffer_start_add(prz, c); + + rem = prz->buffer_size - start; + if (unlikely(rem < c)) { + ret = persistent_ram_update_user(prz, s, start, rem); + s += rem; + c -= rem; + start = 0; + } + if (likely(!ret)) + ret = persistent_ram_update_user(prz, s, start, c); + + persistent_ram_update_header_ecc(prz); + + return unlikely(ret) ? ret : count; +} + size_t persistent_ram_old_size(struct persistent_ram_zone *prz) { return prz->old_log_size; @@ -426,9 +433,6 @@ static void *persistent_ram_iomap(phys_addr_t start, size_t size, return NULL; } - buffer_start_add = buffer_start_add_locked; - buffer_size_add = buffer_size_add_locked; - if (memtype) va = ioremap(start, size); else |