From: Kees Cook
stable inclusion
from stable-5.10
category: feature
commit:93ee4b7d9f0632690713aee604c49e298e634094
issue: #I4919J
--------------------------------
Since the header is a fixed small maximum size, just use a stack variable
to avoid memory allocation in the write path.
Signed-off-by: Kees Cook
(cherry picked from commit 93ee4b7d9f0632690713aee604c49e298e634094)
Signed-off-by: roger
---
fs/pstore/ram.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 5d938d68b2b1..52bf9ba9a139 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -347,19 +347,15 @@ static ssize_t ramoops_pstore_read(struct pstore_record *record)
static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz,
struct pstore_record *record)
{
- char *hdr;
+ char hdr[36]; /* "===="(4), %lld(20), "."(1), %06lu(6), "-%c\n"(3) */
size_t len;
- hdr = kasprintf(GFP_ATOMIC, RAMOOPS_KERNMSG_HDR "%lld.%06lu-%c\n",
+ len = scnprintf(hdr, sizeof(hdr),
+ RAMOOPS_KERNMSG_HDR "%lld.%06lu-%c\n",
(time64_t)record->time.tv_sec,
record->time.tv_nsec / 1000,
record->compressed ? 'C' : 'D');
- if (WARN_ON_ONCE(!hdr))
- return 0;
-
- len = strlen(hdr);
persistent_ram_write(prz, hdr, len);
- kfree(hdr);
return len;
}
--
2.17.1
