From: Basavaraj Natikar Basavaraj.Natikar@amd.com
commit 87854366176403438d01f368b09de3ec2234e0f5 upstream.
Shift operation of 'exp' and 'shift' variables exceeds the maximum number of shift values in the u32 range leading to UBSAN shift-out-of-bounds.
... [ 6.120512] UBSAN: shift-out-of-bounds in drivers/hid/amd-sfh-hid/sfh1_1/amd_sfh_desc.c:149:50 [ 6.120598] shift exponent 104 is too large for 64-bit type 'long unsigned int' [ 6.120659] CPU: 4 PID: 96 Comm: kworker/4:1 Not tainted 6.4.0amd_1-next-20230519-dirty #10 [ 6.120665] Hardware name: AMD Birman-PHX/Birman-PHX, BIOS SFH_with_HPD_SEN.FD 04/05/2023 [ 6.120667] Workqueue: events amd_sfh_work_buffer [amd_sfh] [ 6.120687] Call Trace: [ 6.120690] <TASK> [ 6.120694] dump_stack_lvl+0x48/0x70 [ 6.120704] dump_stack+0x10/0x20 [ 6.120707] ubsan_epilogue+0x9/0x40 [ 6.120716] __ubsan_handle_shift_out_of_bounds+0x10f/0x170 [ 6.120720] ? psi_group_change+0x25f/0x4b0 [ 6.120729] float_to_int.cold+0x18/0xba [amd_sfh] [ 6.120739] get_input_rep+0x57/0x340 [amd_sfh] [ 6.120748] ? __schedule+0xba7/0x1b60 [ 6.120756] ? __pfx_get_input_rep+0x10/0x10 [amd_sfh] [ 6.120764] amd_sfh_work_buffer+0x91/0x180 [amd_sfh] [ 6.120772] process_one_work+0x229/0x430 [ 6.120780] worker_thread+0x4a/0x3c0 [ 6.120784] ? __pfx_worker_thread+0x10/0x10 [ 6.120788] kthread+0xf7/0x130 [ 6.120792] ? __pfx_kthread+0x10/0x10 [ 6.120795] ret_from_fork+0x29/0x50 [ 6.120804] </TASK> ...
Fix this by adding the condition to validate shift ranges.
Fixes: 93ce5e0231d7 ("HID: amd_sfh: Implement SFH1.1 functionality") Cc: stable@vger.kernel.org Tested-by: Kai-Heng Feng kai.heng.feng@canonical.com Signed-off-by: Basavaraj Natikar Basavaraj.Natikar@amd.com Signed-off-by: Akshata MukundShetty akshata.mukundshetty@amd.com Link: https://lore.kernel.org/r/20230707065722.9036-3-Basavaraj.Natikar@amd.com Signed-off-by: Benjamin Tissoires bentiss@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/hid/amd-sfh-hid/sfh1_1/amd_sfh_desc.c | 20 +++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-)
diff --git a/drivers/hid/amd-sfh-hid/sfh1_1/amd_sfh_desc.c b/drivers/hid/amd-sfh-hid/sfh1_1/amd_sfh_desc.c index c81d20cd3081..06bdcf072d10 100644 --- a/drivers/hid/amd-sfh-hid/sfh1_1/amd_sfh_desc.c +++ b/drivers/hid/amd-sfh-hid/sfh1_1/amd_sfh_desc.c @@ -143,16 +143,32 @@ static int float_to_int(u32 flt32_val) if (!exp && !mantissa) return 0;
+ /* + * Calculate the exponent and fraction part of floating + * point representation. + */ exp -= 127; if (exp < 0) { exp = -exp; + if (exp >= BITS_PER_TYPE(u32)) + return 0; zeropre = (((BIT(23) + mantissa) * 100) >> 23) >> exp; return zeropre >= 50 ? sign : 0; }
shift = 23 - exp; - flt32_val = BIT(exp) + (mantissa >> shift); - fraction = mantissa & GENMASK(shift - 1, 0); + if (abs(shift) >= BITS_PER_TYPE(u32)) + return 0; + + if (shift < 0) { + shift = -shift; + flt32_val = BIT(exp) + (mantissa << shift); + shift = 0; + } else { + flt32_val = BIT(exp) + (mantissa >> shift); + } + + fraction = (shift == 0) ? 0 : mantissa & GENMASK(shift - 1, 0);
return (((fraction * 100) >> shift) >= 50) ? sign * (flt32_val + 1) : sign * flt32_val; }