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[lts9.2] oops breaks - #69

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[lts9.2] oops breaks#69
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PlaidCatforce-pushed the {jmaple}_test_ciqlts9_2 branch from 61b9ff1 to 17b5bfaCompareJanuary 16, 2025 20:34
github-actionsBot pushed a commit to bmastbergen/kernel-src-tree that referenced this pull request Apr 7, 2025
In ThinPro, we use the convention <upstream_ver>+hp<patchlevel> for
the kernel package. This does not have a dash in the name or version.
This is built by editing ".version" before a build, and setting
EXTRAVERSION="+hp" and KDEB_PKGVERSION make variables:
echo 68 > .version
make -j<n> EXTRAVERSION="+hp" bindeb-pkg KDEB_PKGVERSION=6.12.2+hp69
.deb name: linux-image-6.12.2+hp_6.12.2+hp69_amd64.deb
Since commit 7d4f07d ("kbuild: deb-pkg: squash
scripts/package/deb-build-option to debian/rules"), this no longer
works. The deb build logic changed, even though, the commit message
implies that the logic should be unmodified.
Before, KBUILD_BUILD_VERSION was not set if the KDEB_PKGVERSION did
not contain a dash. After the change KBUILD_BUILD_VERSION is always
set to KDEB_PKGVERSION. Since this determines UTS_VERSION, the uname
output to look off:
(now) uname -a: version 6.12.2+hp ... #6.12.2+hp69
(expected) uname -a: version 6.12.2+hp ... ctrliq#69
Update the debian/rules logic to restore the original behavior.
Fixes: 7d4f07d ("kbuild: deb-pkg: squash scripts/package/deb-build-option to debian/rules")
Signed-off-by: Alexandru Gagniuc <alexandru.gagniuc@hp.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
github-actionsBot pushed a commit that referenced this pull request Apr 10, 2025
[ Upstream commit 6260406 ]
In ThinPro, we use the convention <upstream_ver>+hp<patchlevel> for
the kernel package. This does not have a dash in the name or version.
This is built by editing ".version" before a build, and setting
EXTRAVERSION="+hp" and KDEB_PKGVERSION make variables:
echo 68 > .version
make -j<n> EXTRAVERSION="+hp" bindeb-pkg KDEB_PKGVERSION=6.12.2+hp69
.deb name: linux-image-6.12.2+hp_6.12.2+hp69_amd64.deb
Since commit 7d4f07d ("kbuild: deb-pkg: squash
scripts/package/deb-build-option to debian/rules"), this no longer
works. The deb build logic changed, even though, the commit message
implies that the logic should be unmodified.
Before, KBUILD_BUILD_VERSION was not set if the KDEB_PKGVERSION did
not contain a dash. After the change KBUILD_BUILD_VERSION is always
set to KDEB_PKGVERSION. Since this determines UTS_VERSION, the uname
output to look off:
(now) uname -a: version 6.12.2+hp ... #6.12.2+hp69
(expected) uname -a: version 6.12.2+hp ... #69
Update the debian/rules logic to restore the original behavior.
Fixes: 7d4f07d ("kbuild: deb-pkg: squash scripts/package/deb-build-option to debian/rules")
Signed-off-by: Alexandru Gagniuc <alexandru.gagniuc@hp.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
github-actionsBot pushed a commit that referenced this pull request Aug 9, 2026
[BUG]
Recently, we encountered a KASAN warning as follows:
BUG: KASAN: slab-out-of-bounds in ccw_putcs+0x8bd/0xa80
Read of size 1 at addr ff11000110067100 by task bash/1209
CPU: 10 UID: 0 PID: 1209 Comm: bash Not tainted 7.2.0-rc3 #69 PREEMPT(full)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014
Call Trace:
<TASK>
...
kasan_report+0xf0/0x120
? ccw_putcs+0x8bd/0xa80
ccw_putcs+0x8bd/0xa80
? __pfx_ccw_putcs+0x10/0x10
fbcon_putcs+0x338/0x410
? __pfx_ccw_putcs+0x10/0x10
do_update_region+0x21d/0x450
invert_screen+0x29d/0x5e0
? __kmalloc_noprof+0x493/0x640
? vc_do_resize+0x17c/0xe50
clear_selection+0x4c/0x60
vc_do_resize+0xaee/0xe50
fbcon_modechanged+0x2bd/0x640
rotate_all_store+0x298/0x380
...
reproduce:
1) issue two ioctls: first a KDFONTOP ioctl with op.op = KD_FONT_OP_SET,
op.width = 1 and op.height = 1, then a TIOCL_SETSEL ioctl
2) echo 2 > /sys/devices/virtual/graphics/fbcon/rotate_all
3) issue two ioctls: first a KDFONTOP ioctl with op.op = KD_FONT_OP_SET,
op.width = 8 and op.height = 1, then a TIOCL_SETSEL ioctl
4) echo 3 > /sys/devices/virtual/graphics/fbcon/rotate_all
[CAUSE]
The root cause is that fbcon_modechanged() first sets the current rotate's
corresponding ops. Subsequently, during vc_resize(), it may trigger
clear_selection(), and in fbcon_putcs->ccw_putcs[rotate=3], this can result
in an out-of-bounds access to "src". This happens because par->rotated.buf
is reallocated in fbcon_rotate_font():
1) When rotate=2, its size is (width + 7) / 8 * height
2) When rotate=3, its size is (height + 7) / 8 * width
And the call to fbcon_rotate_font() occurs after clear_selection(). In
other words, the fontbuffer is allocated using the size calculated from the
previous rotation 2, but before reallocating it with the new size,
con_putcs is already using the new rotation 3:
rotate_all_store
fbcon_rotate_all
fbcon_set_all_vcs
fbcon_modechanged
set_blitting_type
...
par->bitops = &ccw_fbcon_bitops
vc_resize
...
clear_selection
highlight
...
do_update_region
fbcon_putcs
...
image.dy = vyres - ((xx + count) * vc->vc_font.width) [1] // overflow!
ccw_putcs_aligned
// old buf size is still being used during the read!
src = par->rotated.buf + (scr_readw(s--) & charmask) * cellsize
fb_pad_aligned_buffer----[src KASAN!!!]	[2]
info->fbops->fb_imageblit(info, image)
sys_imageblit
fb_imageblit
fb_address_forward
// offset: image->dy * bits_per_line + image->dx * bpp
unsigned int bits = (unsigned int)adr->bits + offset
adr->address += (bits & ~(BITS_PER_LONG - 1u)) / BITS_PER_BYTE	[3]
fb_bitmap_imageblit
...
fb_read_offset	// page fault!	[4]
update_screen
redraw_screen
...
ccw_cursor
soft_cursor
memcpy(src, image->data, dsize)----[src KASAN again!!!]	[5]
fbcon_switch
fbcon_rotate_font
font_data_rotate
dst = kmalloc_array(charcount, d_cellsize, GFP_KERNEL)
// the new size is allocated only here!
par->rotated.buf = buf	[6]
[FIX]
A fairly obvious approach is to follow fbcon_switch(): in
fbcon_modechanged(), call rotate_font() before vc_resize() so that a
correctly sized buffer is allocated in time, as done in [6]. This fix is
necessary, but it is not sufficient on its own.
In [1] it causes an image.dy overflow (ccw_putcs: vyres = 768,
image.dy = 4294967040), because vc_cols has not been updated in time at
this point (it is likewise only updated after clear_selection()). This
allows (xx + count) * width to exceed vyres, causing image.dy to overflow.
Subsequently, address in [3] is incremented by an even larger amount, which
triggers a page fault at [4].
Therefore, a second fix is required in combination with the first: move
clear_selection() earlier, before set_blitting_type() in
fbcon_set_all_vcs(), to prevent the out-of-bounds access. fbcon_rotate()
has a similar problem, so add the same clear there. Since vc_is_sel() is
not exported, the fbdev side is currently forced to call clear_selection()
unconditionally, causing the global selection to be cleared prematurely.
And this will not cause any other significant impact.
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Signed-off-by: Helge Deller <deller@gmx.de>
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