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| author | Nicolas Pitre <nico@fluxnic.net> | 2020-03-28 22:25:11 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-04-23 15:46:30 +0200 |
| commit | 9a98e7a80f95378c9ee0c644705e3b5aa54745f1 (patch) | |
| tree | 0cb2689f274fa61f093e60a89f4f1c47b4aca8b3 | |
| parent | 66bb1c9518e623235cbaa7832c919eb4fe586cae (diff) | |
| download | linux-9a98e7a80f95378c9ee0c644705e3b5aa54745f1.tar.bz2 | |
vt: don't use kmalloc() for the unicode screen buffer
Even if the actual screen size is bounded in vc_do_resize(), the unicode
buffer is still a little more than twice the size of the glyph buffer
and may exceed MAX_ORDER down the kmalloc() path. This can be triggered
from user space.
Since there is no point having a physically contiguous buffer here,
let's avoid the above issue as well as reducing pressure on high order
allocations by using vmalloc() instead.
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Cc: <stable@vger.kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.2003282214210.2671@knanqh.ubzr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/vt/vt.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index 309a39197be0..3272759b1f3c 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -81,6 +81,7 @@ #include <linux/errno.h> #include <linux/kd.h> #include <linux/slab.h> +#include <linux/vmalloc.h> #include <linux/major.h> #include <linux/mm.h> #include <linux/console.h> @@ -350,7 +351,7 @@ static struct uni_screen *vc_uniscr_alloc(unsigned int cols, unsigned int rows) /* allocate everything in one go */ memsize = cols * rows * sizeof(char32_t); memsize += rows * sizeof(char32_t *); - p = kmalloc(memsize, GFP_KERNEL); + p = vmalloc(memsize); if (!p) return NULL; @@ -366,7 +367,7 @@ static struct uni_screen *vc_uniscr_alloc(unsigned int cols, unsigned int rows) static void vc_uniscr_set(struct vc_data *vc, struct uni_screen *new_uniscr) { - kfree(vc->vc_uni_screen); + vfree(vc->vc_uni_screen); vc->vc_uni_screen = new_uniscr; } |